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Sample records for pentosus strain isolated

  1. Formation of In Vitro Mixed-Species Biofilms by Lactobacillus pentosus and Yeasts Isolated from Spanish-Style Green Table Olive Fermentations.

    Science.gov (United States)

    León-Romero, Ángela; Domínguez-Manzano, Jesús; Garrido-Fernández, Antonio; Arroyo-López, Francisco Noé; Jiménez-Díaz, Rufino

    2016-01-15

    The present work details the in vitro interactions between Lactobacillus pentosus and yeast strains isolated from table olive processing to form mixed biofilms. Among the different pairs assayed, the strongest biofilms were obtained from L. pentosus and Candida boidinii strain cocultures. However, biofilm formation was inhibited in the presence of d-(+)-mannose. In addition, biofilm formation by C. boidinii monoculture was stimulated in the absence of cell-cell contact with L. pentosus. Scanning electron microscopy revealed that a sort of "sticky" material formed by the yeasts contributed to substrate adherence. Hence, the data obtained in this work suggest that yeast-lactobacilli biofilms may be favored by the presence of a specific mate of yeast and L. pentosus, and that more than one mechanism might be implicated in the biofilm formation. This knowledge will help in the design of appropriate mixed starter cultures of L. pentosus-yeast species pairs that are able to improve the quality and safety of Spanish-style green table olive processing. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  2. Lactobacillus Pentosus KCA1 does not alter Haematological ...

    African Journals Online (AJOL)

    The use of probiotics is yet to be given attention in Nigeria, perhaps due to lack scientific clinical studies on local isolates. In order to introduce the concept, we used the first sequenced Lactobacillus pentosus KCA1 strain isolated in a healthy Nigerian subject. This strain produces biosurfactants, hydrogen peroxide, lactic ...

  3. Lactobacillus pentosus B231 Isolated from a Portuguese PDO Cheese: Production and Partial Characterization of Its Bacteriocin.

    Science.gov (United States)

    Guerreiro, Joana; Monteiro, Vitor; Ramos, Carla; Franco, Bernadette Dora Gombossy de Melo; Martinez, Rafael Chacon Ruiz; Todorov, Svetoslav Dimitrov; Fernandes, Paulo

    2014-06-01

    Bacteriocin B231 produced by Lactobacillus pentosus, isolated from an artisanal raw cow's milk protected designation of origin Portuguese cheese, is a small protein with an apparent relative mass of about 5 kDa and active against a large number of Listeria monocytogenes wild-type strains, Listeria ivanovii and Listeria innocua. Bacteriocin B231 production is highly dependent on the type of the culture media used for growth of Lact. pentosus B231. Replacement of glucose with maltose yielded the highest bacteriocin production from eight different carbon sources. Similar results were recorded in the presence of combination of glucose and maltose or galactose. Production of bacteriocin B231 reached maximal levels of 800 AU/ml during the stationary phase of growth of Lact. pentosus B231 in MRS broth at 30 °C. Bacteriocin B231 (in cell-free supernatant) was sensitive to treatment with trypsin and proteinase K, but not affected by the thermal treatment in range of 55-121 °C, or freezing (-20 °C). Bacteriocin production and inhibitory spectrum were evaluated. Gene encoding plantaricin S has been detected in the genomic DNA. Virulence potential and safety of Lact. pentosus B231 were assessed by PCR targeted the genes gelE, hyl, asa1, esp, cylA, efaA, ace, vanA, vanB, hdc1, hdc2, tdc and odc. The Lact. pentosus B231 strains harbored plantaricin S gene, while the occurrence of virulence, antibiotic resistance and biogenic amine genes was limited to cytolysin, hyaluronidase, aggregation substance, adhesion of collagen protein, gelatinase, tyrosine decarboxylase and vancomycin B genes.

  4. Characterisation of autolytic enzymes in Lactobacillus pentosus.

    Science.gov (United States)

    Cibik, R; Chapot-Chartier, M-P

    2004-01-01

    To characterize autolysis and autolytic system of the lactic acid bacterium Lactobacillus pentosus. Autolysis of nine Lact. pentosus strains was evaluated in buffer solution. Their peptidoglycan hydrolase profiles were examined by renaturing SDS-PAGE and revealed two major activity bands at 58 and 112 kDa. Specificity analysis indicated the presence of at least two different types of peptidoglycan hydrolase activities in Lact. pentosus 1091. Autolysis of Lact. pentosus was shown to be strain dependent and involvement of at least two different autolysins was evidenced. The autolytic system of Lact. pentosus was characterized for the first time and the data obtained could be used in the selection of strains of technological interest.

  5. Evaluation of a single and combined inoculation of a Lactobacillus pentosus starter for processing cv. Arbequina natural green olives.

    Science.gov (United States)

    Hurtado, Albert; Reguant, Cristina; Bordons, Albert; Rozès, Nicolas

    2010-09-01

    The production of Arbequina naturally green olives is a traditional and spontaneous process in which lactic acid bacteria (LAB) and yeasts are present. To better control the fermentation of olives, strains of LAB and yeasts that had been isolated from brines were used in this study. A strain of Lactobacillus pentosus selected from an industrial olive fermentation was used as a starter culture for the traditional fermentation of Arbequina naturally green olives. Three more strains isolated from Arbequina olive brines were selected: one yeast, (Candida diddensiae), and two Lactobacillus (one L. plantarum and the other L. pentosus). The individual fermentation profile of all the strains and the co-inoculation profile of each one of the three with the first selected L. pentosus were studied in pilot-scale fermentations. The results showed that all the strains used as a starter, and particularly the yeast C. diddensiae, reduced the Enterobacteriaceae survival period in comparison with the spontaneous process. Only when a L. pentosus strain was inoculated were the LAB counts above 10(6) cfu ml(-1) throughout the process. The C. diddensiae starter failed to colonize the brine until the end of the process and no LAB were detected. Results of rep-PCR using the primer GTG(5) showed that both L. pentosus starters were able to colonize the brine by the end of the process but when they were co-inoculated only one strain was dominant. The L. plantarum starter failed to colonize the brine. In the control fermentation, various autochthonous strains of L. pentosus and L. plantarum were detected. The pH only reached desirable levels when a L. pentosus strain was inoculated. From the results of the sensory evaluation, panellists found significant differences between the different starters used for fermenting olives. Copyright 2010 Elsevier Ltd. All rights reserved.

  6. Fermented Aloreña Table Olives as a Source of Potential Probiotic Lactobacillus pentosus Strains.

    Science.gov (United States)

    Montoro, Beatriz Pérez; Benomar, Nabil; Lavilla Lerma, Leyre; Castillo Gutiérrez, Sonia; Gálvez, Antonio; Abriouel, Hikmate

    2016-01-01

    A collection of 31 Lactobacillus pentosus strains isolated from naturally fermented Aloreña green table olives were screened in depth in the present study for their probiotic potential. Several strains could be considered promising probiotic candidates since they showed good growth capacity and survival under simulated gastro-intestinal conditions (acidic pH of 1.5, up to 4% of bile salts and 5 mM of nitrate), good ability to auto-aggregate which may facilitate their adhesion to host cells as multiple aggregates and the subsequent displacement of pathogens. Moreover, co-aggregation of lactobacilli with pathogenic bacteria was shown with Listeria innocua, Staphylococcus aureus, Escherichia coli , and Salmonella Enteritidis as good defense strategy against gut and food pathogens. Furthermore, they exhibited adherence to intestinal and vaginal cell lines, such property could be reinforced by their capacity of biofilm formation which is also important in food matrices such as the olive surface. Their antagonistic activity against pathogenic bacteria by means of acids and plantaricins, and also their different functional properties may determine their efficacy not only in the gastro-intestinal tract but also in food matrices. Besides their ability to ferment several prebiotics, the new evidence in the present study was their capacity to ferment lactose which reinforces their use in different food matrices including dairy as a dietary adjunct to improve lactose digestibility. Lactobacillus pentosus CF2-10N was selected to have the best probiotic profile being of great interest in further studies. In conclusion, spontaneous fermented Aloreña table olives are considered a natural source of potential probiotic L. pentosus to be included as adjunct functional cultures in different fermented foods.

  7. Fermented Aloreña table olives as a source of potential probiotic Lactobacillus pentosus strains

    Directory of Open Access Journals (Sweden)

    Beatriz Pérez Montoro

    2016-10-01

    Full Text Available A collection of 31 Lactobacillus pentosus strains isolated from naturally fermented Aloreña green table olives were screened in depth in the present study for their probiotic potential. Several strains could be considered promising probiotic candidates since they showed good growth capacity and survival under simulated gastro-intestinal conditions (acidic pH of 1.5, up to 4% of bile salts and 5 mM of nitrate, good ability to auto-aggregate which may facilitate their adhesion to host cells as multiple aggregates and the subsequent displacement of pathogens. Moreover, co-aggregation of lactobacilli with pathogenic bacteria was shown with Listeria innocua, Staphylococcus aureus, Escherichia coli and Salmonella Enteriditis as good defense strategy against gut and food pathogens. Furthermore, they exhibited adherence to intestinal and vaginal cell lines, such property could be reinforced by their capacity of biofilm formation which is also important in food matrices such as the olive surface. Their antagonistic activity against pathogenic bacteria by means of acids and plantaricins, and also their different functional properties may determine their efficacy not only in the gastro-intestinal tract but also in food matrices. Besides their ability to ferment several prebiotics, the new evidence in the present study was their capacity to ferment lactose which reinforces their use in different food matrices including dairy as a dietary adjunct to improve lactose digestibility. Lactobacillus pentosus CF2-10N was selected to have best probiotic profile being of great interest in further studies. In conclusion, spontaneous fermented Aloreña table olives are considered a natural source of potential probiotic Lb. pentosus to be included as adjunct functional cultures in different fermented foods.

  8. Inoculated fermentation of green olives with potential probiotic Lactobacillus pentosus and Lactobacillus plantarum starter cultures isolated from industrially fermented olives.

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    Blana, Vasiliki A; Grounta, Athena; Tassou, Chrysoula C; Nychas, George-John E; Panagou, Efstathios Z

    2014-04-01

    The performance of two strains of lactic acid bacteria (LAB), namely Lactobacillus pentosus B281 and Lactobacillus plantarum B282, previously isolated from industrially fermented table olives and screened in vitro for probiotic potential, was investigated as starter cultures in Spanish style fermentation of cv. Halkidiki green olives. Fermentation was undertaken at room temperature in two different initial salt concentrations (8% and 10%, w/v, NaCl) in the brines. The strains were inoculated as single and combined cultures and the dynamics of their population on the surface of olives was monitored for a period of 114 days. The survival of inoculated strains on olives was determined using Pulsed Field Gel Electrophoresis (PFGE). Both probiotic strains successfully colonized the olive surface at populations ranged from 6.0 to 7.0 log CFU/g throughout fermentation. PFGE analysis revealed that L. pentosus B281 presented higher colonization in both salt levels at the end of fermentation (81.2% and 93.3% in 8% and 10% NaCl brines, respectively). For L. plantarum B282 a high survival rate (83.3%) was observed in 8% NaCl brines, but in 10% NaCl the strain could not colonize the surface of olives. L. pentosus B281 also dominated over L. plantarum B282 in inoculated fermentations when the two strains were used as combined culture. The biochemical profile (pH, organic acids, volatile compounds) attained during fermentation and the sensory analysis of the final product indicated a typical lactic acid fermentation process of green olives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Purification and characterisation of an extracellular fructan beta-fructosidase from a Lactobacillus pentosus strain isolated from fermented fish

    DEFF Research Database (Denmark)

    Paludan-Müller, Christine; Gram, Lone; Rattray, F.P.

    2002-01-01

    Lactobacillus pentosus B235, which was isolated as part of the dominant microflora from a garlic containing fermented fish product, was grown in a chemically defined medium With inulin as the sole carbohydrate source. An extracellular fructan beta- fructosidase was purified to homogeneity from...... fructan), but also hydrolysed garlic extract, (a beta(2-->1)-linked fructan with beta(2-->6)-linked fructosyl sidechains), 1,1,1-kestose, 1,1-kestose, 1-kestose, inulin (beta(2-->1)-linked fructans) and Sucrose at 60, 45, 39, 12, 9 and 3%, respectively, of the activity observed for levan. Melezitose...

  10. Growth of indigenous lactic acid bacteria Lactobacillus plantarum-pentosus T14 and Lactobacillus plantarum-pentosus T35 in kerandang (Canavalia virosa milk and changes of raffinose

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    Rahayu, E. S.

    2013-01-01

    Full Text Available Aims: Kerandang (Canavalia virosa beans are good source of protein, yet predominantly kerandang foods are not widely accepted mainly because of their beany flavour the belief that they cause flatulence. The objectives of this research were to evaluate of viability of lactic acid bacteria from Indonesia indigenous fermented food in kerandang milk and its ability to metabolize indigestible oligossacharide raffinose.Methodology and results: Two strains of Indonesia indigenous lactic acid bacteria (LAB, namely Lactobacillus plantarum-pentosus T14 and Lactobacillus plantarum-pentosus T35 were used for fermentation of kerandang milk. The results showed that all strains of lactic acid bacteria possess the ability to grow and produce of lactic acid in kerandang milk, indicated that total acid (TA increase, pH decrease and their counts of LAB increase during fermentation period (0-24 h. The two strains of lactic acid bacteria were also able to metabolize raffinose into simple sugar (sucrose, glucose, fructose and galactose during fermentation at 37 °C, however the raffinose transformation by L. plantarum-pentosus T14 more ability than L. plantarum-pentosus T35. The metabolism of raffinose during fermentation by L. plantarum-pentosus T14 and L. plantarum-pentosus T35 were 98.23% and 48.98%, respectively.Conclusion, significance and impact of study: Kerandang milk fermented by lactic acid bacteria can decrease of saccharide raffinose cause of flatulence. Thus, lactic fermented of kerandang milk be safer for consumption.

  11. Selection of oleuropein-degrading lactic acid bacteria strains isolated from fermenting Moroccan green olives

    Energy Technology Data Exchange (ETDEWEB)

    Ghabbour, N.; Lamzira, Z.; Thonart, P.; Cidalia, P.; Markaouid, M.; Asehraoua, A.

    2011-07-01

    A total of 177 strains of lactic acid bacteria (LAB) were isolated from early-stage Moroccan Picholine green olive fermentation, including Lactobacillus plantarum (44.63%), Lactobacillus pentosus (25.99%), Lactobacillus brevis (9.61%) and Pediococcus pentosaceus (19.77%). All the isolates were screened for their tolerance to olive leaf extract and oleuropein. Most of the isolates (85.3%) were found able to degrade oleuropein, when evaluated by either oleuropein or 5-Bromo-4-chloro-3-indolyl {beta}-D-glucuronide (X-Gluc) as substrates. The biodegradation capacity of the selected strains of each species was confirmed by HPLC analysis. (Author).

  12. Characterization of indigenous lactobacillus strains for probiotic properties.

    Science.gov (United States)

    Mojgani, Naheed; Hussaini, Fatimah; Vaseji, Narges

    2015-02-01

    Probiotics are defined as adequate amount of live microorganisms able to confer health benefits on the host. Currently, most commercially available probiotic products in the market belong to genera Lactobacillus. Traditional dairy products are usually rich source of Lactobacillus strains with significant health benefits. In order to evaluate the probiotic potential of these bacteria, it is essential to assess their health benefits, efficacy, and safety. The probiotic efficacy of two Lactobacillus strains namely Lactobacillus pentosus LP05 and L. brevis LB32 was evaluated. They were previously isolated from ewes' milk in a rural area in East Azerbaijan, Iran. The selected isolates were tested for certain phenotypic characters and identified to genus and species level by 16S rRNA gene sequencing and species specific primers. Further analysis included acid and bile resistance, antagonistic activity, cholesterol removing ability, survival in simulated gastric and upper intestine contents, aggregation and coaggregation properties. Finally, the adhering ability of the selected Lactobacillus strains to epithelial cells was tested using Caco-2 cell lines. The selected isolates tolerated bile salt concentrations ranging from 0.5% to 3%, however their coefficient of inhibition were varied. Both isolates hydrolyzed bile and grew at pH values of 3, 4, and 5, while isolate LP05 was not able to hydrolyze arginine. Based on 16s rRNA gene sequencing and species-specific primers, the isolates were identified as L. brevis LB32 and L. pentosus LP05. In contrast to simulated gastric conditions, the growth rate of the isolates in alkaline conditions of upper intestine increased significantly with the passage of time reaching its maximum in 24 hours. These 2 isolates inhibited the growth of Listeria monocytogenes, Salmonella enteritidis, Shigella dysenteriae, Staphylococcus aureus, and Streptococcus pneumonia. Furthermore, L. brevis LB32 was able to reduce approximately 86% of

  13. In Lactobacillus pentosus, the olive brine adaptation genes are required for biofilm formation.

    Science.gov (United States)

    Perpetuini, G; Pham-Hoang, B N; Scornec, H; Tofalo, R; Schirone, M; Suzzi, G; Cavin, J F; Waché, Y; Corsetti, A; Licandro-Seraut, H

    2016-01-04

    Lactobacillus pentosus is one of the few lactic acid bacteria (LAB) species capable of surviving in olive brine, and thus desirable during table olive fermentation. We have recently generated mutants of the efficient strain L. pentosus C11 by transposon mutagenesis and identified five mutants unable to survive and adapt to olive brine conditions. Since biofilm formation represents one of the main bacterial strategy to survive in stressful environments, in this study, the capacity of adhesion and formation of biofilm on olive skin was investigated for this strain and five derivative mutants which are interrupted in metabolic genes (enoA1 and gpi), and in genes of unknown function ("oba" genes). Confocal microscopy together with bacteria count revealed that the sessile state represented the prevailing L. pentosus C11 life-style during table olive fermentation. The characterization of cell surface properties showed that mutants present less hydrophobic and basic properties than the wild type (WT). In fact, their ability to adhere to both abiotic (polystyrene plates) and biotic (olive skin) surfaces was lower than that of the WT. Confocal microscopy revealed that mutants adhered sparsely to the olive skin instead of building a thin, multilayer biofilm. Moreover, RT-qPCR showed that the three genes enoA1, gpi and obaC were upregulated in the olive biofilm compared to the planktonic state. Thus enoA1, gpi and "oba" genes are necessary in L. pentosus to form an organized biofilm on the olive skin. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. In silico genomic insights into aspects of food safety and defense mechanisms of a potentially probiotic Lactobacillus pentosus MP-10 isolated from brines of naturally fermented Aloreña green table olives.

    Directory of Open Access Journals (Sweden)

    Hikmate Abriouel

    Full Text Available Lactobacillus pentosus MP-10, isolated from brines of naturally fermented Aloreña green table olives, exhibited high probiotic potential. The genome sequence of L. pentosus MP-10 is currently considered the largest genome among lactobacilli, highlighting the microorganism's ecological flexibility and adaptability. Here, we analyzed the complete genome sequence for the presence of acquired antibiotic resistance and virulence determinants to understand their defense mechanisms and explore its putative safety in food. The annotated genome sequence revealed evidence of diverse mobile genetic elements, such as prophages, transposases and transposons involved in their adaptation to brine-associated niches. In-silico analysis of L. pentosus MP-10 genome sequence identified a CRISPR (clustered regularly interspaced short palindromic repeats/cas (CRISPR-associated protein genes as an immune system against foreign genetic elements, which consisted of six arrays (4-12 repeats and eleven predicted cas genes [CRISPR1 and CRISPR2 consisted of 3 (Type II-C and 8 (Type I genes] with high similarity to L. pentosus KCA1. Bioinformatic analyses revealed L. pentosus MP-10 to be absent of acquired antibiotic resistance genes, and most resistance genes were related to efflux mechanisms; no virulence determinants were found in the genome. This suggests that L. pentosus MP-10 could be considered safe and with high-adaptation potential, which could facilitate its application as a starter culture and probiotic in food preparations.

  15. In Vitro Evaluation of the Probiotic Potential of Halotolerant Lactobacilli Isolated from a Ripened Tropical Mexican Cheese.

    Science.gov (United States)

    Melgar-Lalanne, Guiomar; Rivera-Espinoza, Yadira; Reyes Méndez, Ana Itzel; Hernández-Sánchez, Humberto

    2013-12-01

    Three halotolerant lactobacilli (Lactobacillus plantarum, L. pentosus, and L. acidipiscis) isolated from a ripened Mexican tropical cheese (double cream Chiapas cheese) were evaluated as potential probiotics and compared with two commercial probiotic strains (L. casei Shirota and L. plantarum 299v) from human origin. All the strains survived the in vitro gastrointestinal simulation from the oral cavity to the ileum. During the stomach simulation, all the strains survived in satiety conditions (60 min, pH 3.0, 3 g/L pepsin, 150 rpm) and only L. pentosus could not survive under fasting conditions (60 min, pH 2.0, 3 g/L pepsin, 150 rpm). All the strains showed a strong hydrophilic character with low n-hexadecane and a variable chloroform affinity. L. plantarum showed a mucin adhesion rate similar to that of L. plantarum 299v and L. casei Shirota, while L. pentosus and L. acidipiscis had a lower mucin adhesion. The isolated halotolerant lactobacilli exhibited similar antimicrobial activity against some gram-positive and gram-negative pathogens in comparison with the two commercial strains. In addition, the proteinaceous character of the antimicrobial agents against the most pathogenic strains was demonstrated. The compounds showed a low molecular weight (less than 10 kDa). Besides, L. plantarum and L. acidipiscis were able to produce the enzyme β-galactosidase. Finally, L. pentosus was able to deconjugate taurocholic, taurodeoxycholic, glycocholic, and glycodeoxycholic acids better than the two commercial strains analyzed. All these results suggest that the halotolerant lactobacilli isolated from this ripened Mexican cheese could be potentially probiotic. This is the first time that halotolerant lactic acid bacteria have been shown to have probiotic properties.

  16. Purification, Characterization, and Mode of Action of Pentocin JL-1, a Novel Bacteriocin Isolated from Lactobacillus pentosus, against Drug-Resistant Staphylococcus aureus

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    Han Jiang

    2017-01-01

    Full Text Available Staphylococcus aureus and its drug-resistant strains, which threaten public health and food safety, are in need of effective control by biopreservatives. A novel bacteriocin, pentocin JL-1, produced by Lactobacillus pentosus that was isolated from the intestinal tract of Chiloscyllium punctatum, was purified by a four-step chromatographic process. Mass spectrometry based on MALDI-TOF indicated that pentocin JL-1 has a molecular mass of 2987.23 Da. Only six of the twenty-five amino acids could be identified by Edman degradation. This bacteriocin is thermostable and tolerates a pH range of 5–7. Also, it is sensitive to proteinase K, trypsin, pepsin, and alkaline protease. This bacteriocin has a broad inhibitory spectrum against both Gram-positive and Gram-negative strains and in particular is effective against multidrug-resistant S. aureus. Additionally, we showed that the cell membrane is the target of pentocin JL-1 against methicillin-resistant S. aureus (MRSA, causing a loss of proton motive force. Furthermore, pentocin JL-1 has a drastic impact on the structure and integrity of MRSA cells. These results suggest that pentocin JL-1 has potential as a biopreservative in the food industry.

  17. Lactic acid production from wheat straw hemicellulose hydrolysate by Lactobacillus pentosus and Lactobacillus brevis

    DEFF Research Database (Denmark)

    Garde, Arvid; Jonsson, Gunnar Eigil; Schmidt, A. S.

    2002-01-01

    Lactic acid production by Lactobacillus brevis and Lactobacillus pentosus on a hemicellulose hydrolysate (HH) of wet-oxidized wheat straw was evaluated. The potential of 11-12 g/l fermentable sugars was released from the HH through either enzymatic or acidic pretreatment. Fermentation of added......% of the theoretical maximum yield after enzymatic, or acid treatment of HH, respectively. Individually, neither of the two strains were able to fully utilize the relatively broad spectra of sugars released by the acid and enzyme treatments; however, lactic acid production increased to 95% of the theoretical maximum...... yield by co-inoculation of both strains. Xylulose was the main sugar released after enzymatic treatment of HH with Celluclast(R). Lb. brevis was able to degrade xylobiose, but was unable to assimilate xylulose, whereas Lb. pentosus was able to assimilate xylulose but unable to degrade xylobiose. (C...

  18. Genotypic analyses of lactobacilli with a range of tannase activities isolated from human feces and fermented foods.

    Science.gov (United States)

    Nishitani, Yosuke; Sasaki, Eiki; Fujisawa, Tomohiko; Osawa, Ro

    2004-02-01

    A total of 77 tannase producing lactobacilli strains isolated from human feces or fermented foods were examined for their genotypic profiles and intensities of tannase production. With a PCR-based assay targeting recA gene, all strains except one isolate were assigned to either Lactobacillus plantarum, L. paraplantarum, or L. pentosus whereas a 16/23S rDNA targeted PCR-based assay identified all except 6 isolates (inclusive of the above one isolate) as one of the closely related species. Subsequent DNA/DNA hybridization assays revealed that these 6 exceptional isolates showed low homology (between 1.2% and 55.8% relative DNA binding) against type strains of the three species. Supplemental carbohydrate fermentation profiles on the 6 isolates indicated that two of them were identified as L. acidophilus, one as Pediococcus acidilactici, one as P. pentosaceus, and two remained unidentifiable. The evidence suggests that the 16/23S rDNA targeted PCR assay can be used as a reliable identification tool for the closely related lactobacilli, and that the tannase gene is widely distributed within members of the Lactobacillaceae family. Meanwhile, a randomly amplified polymorphism DNA (RAPD) analysis revealed that all except 8 isolates were well allocated in 4 major RAPD clusters, though not species specific, consisting of two L. plantarum predominant clusters, one L. paraplantarum predominant, and one L. pentosus predominant. The RAPD patterns of the 8 non-clustered isolates, which consisted of the 6 unidentifiable isolates and 2 isolates identified as L. pentosus, were tannase activities showed that there was a marked variation in the activities among the strains, which did not correlate with either species identification or clustering by RAPD.

  19. Functional expression in Lactobacillus plantarum of xylP encoding the isoprimeverose transporter of Lactobacillus pentosus

    NARCIS (Netherlands)

    Chaillou, S.; Postma, P.W.; Pouwels, P.H.

    1998-01-01

    The xylP gene of Lactobacillus pentosus, the first gene of the xylPQR operon, was recently found to be involved in isoprimeverose metabolism. By expression of xylP on a multicopy plasmid in Lactobacillus plantarum 80, a strain which lacks active isoprimeverose and D-xylose transport activities, it

  20. Characterization of Partially Purified Bacteriocin Like Substance (BLIS Produced by Probiotic Lactobacillus Strains

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    Saeed Ismail Khanian

    2014-05-01

    Full Text Available Background: There is an increasing interest in search for antimicrobial peptides (bacteriocins and bacteriocin-like compounds produced by lactic acid bacteria (LAB because of their potential to be used as antimicrobial agents for improving the safety of food products. Objectives: The main objective of study was to evaluate the antibacterial potential of locally isolated Lactic Acid bacteria (LAB and determine their bacteriocin producing ability in in-vitro conditions. Materials and Methods: The antibacterial activity of 77 isolated LAB strains was tested against a number of pathogens by well-diffusion method. The isolates demonstrating antimicrobial potential were selected and tested for the production of bacteriocin or bacteriocin like substance. The bacteriocin produced by two of the isolates were partially purified and characterized. Results: The results indicated the neutralized supernatant fluid of two of the isolates identified as L. brevis LB32 and L. pentosus LP05, were active against the growth of Listeria monocytogenes, Salmonella enteritidis, Shigella dysenteriae, Staphylococcus aureus and Streptococcus pneumoniae. Additionally, L. brevis LB32 was able to inhibit the growth of Salmonella typhi and Klebsiella pneumoniae, while, S. pnuemoniae and L. monocytogenes appeared to be the most sensitive strain as apparent by highest zone of inhibition against these pathogens, respectively. The antimicrobial activity in the supernatant fluids of the mentioned strains remained unaffected after treating with enzymes catalase, lipase and lysozyme, while were strongly sensitive to the action of proteolytic enzymes, suggesting the presence of bacteriocin like inhibitory substance (BLIS in the two isolates. The inhibitory substance produced by the two isolates appeared heat resistant and tolerated 100˚C and 121˚C for 55 minutes and 20 minutes, respectively. Partial purification of the concentrated culture supernatant fluids of L. brevis LB32 and L

  1. Improved acid tolerance of Lactobacillus pentosus by error-prone whole genome amplification.

    Science.gov (United States)

    Ye, Lidan; Zhao, Hua; Li, Zhi; Wu, Jin Chuan

    2013-05-01

    Acid tolerance of Lactobacillus pentosus ATCC 8041 was improved by error-prone amplification of its genomic DNA using random primers and Taq DNA polymerase. The resulting amplification products were transferred into wild-type L. pentosus by electroporation and the transformants were screened for growth on low-pH agar plates. After only one round of mutation, one mutant (MT3) was identified that was able to completely consume 20 g/L of glucose to produce lactic acid at a yield of 95% in 1L MRS medium at pH 3.8 within 36 h, whereas no growth or lactic acid production was observed for the wild-type strain under the same conditions. The acid tolerance of mutant MT3 remained genetically stable for at least 25 subcultures. Therefore, the error-prone whole genome amplification technique is a very powerful tool for improving phenotypes of this lactic acid bacterium and may also be applicable for other microorganisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. “PENTOYO” with a Fully Sequenced Lactobacillus pentosus KCA1 ...

    African Journals Online (AJOL)

    Purpose: To determine whether L. pentosus KCA1 can be used to create a new probiotic yogurt and the organism's duration of survival when stored at 4 oC. Methods: Mother cultures of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus and L. pentosus KCA1 were prepared and subsequently ...

  3. In vitro probiotic characterization of Lactobacillus strains from fermented radish and their anti-adherence activity against enteric pathogens.

    Science.gov (United States)

    Damodharan, Karthiyaini; Palaniyandi, Sasikumar Arunachalam; Yang, Seung Hwan; Suh, Joo-Won

    2015-11-01

    In this study, we evaluated the probiotic properties of Lactobacillus plantarum, Lactobacillus pentosus, and Lactobacillus fermentum strains isolated from fermented radish. All the strains survived the simulated oro-gastrointestinal transit condition and showed significantly higher adherence to Caco-2 cells compared with the probiotic strain Lactobacillus rhamnosus GG. The strains showed broad-spectrum antimicrobial activity, autoaggregation, and coaggregation capacity with pathogens. Furthermore, the Lactobacillus strains inhibited the adherence of Yersinia enterocolitica subsp. enterocolitica, Shigella boydii, and Salmonella choleraesuis to the Caco-2 cell line. The strains possessed bile salt hydrolase activity and their cholesterol-lowering activity in vitro was above 50% in the presence of bile. Strains of L. plantarum and L. pentosus possessed the plantaricin-encoding plnEF gene. In addition, the Lactobacillus strains maintained about 80% cell viability after freeze-drying in the presence of a combination of 5% skim milk and 5% maltodextrin as cryoprotectant, and 70% recovery of cell viability was observed in the absence of any cryoprotectant.

  4. Biofilm formation on Conservolea natural black olives during single and combined inoculation with a functional Lactobacillus pentosus starter culture.

    Science.gov (United States)

    Grounta, Athena; Doulgeraki, Agapi I; Nychas, George-John E; Panagou, Efstathios Z

    2016-06-01

    The potential of biofilm formation of multifunctional starters Lactobacillus pentosus B281 and Pichia membranifaciens M3A during inoculated fermentation of Conservolea natural black olives according to Greek-style processing was investigated. Olives were directly brined in 8% (w/v) NaCl following three fermentation procedures namely, i) spontaneous fermentation, ii) inoculated fermentation with L. pentosus B281, and iii) co-inoculated fermentation with L. pentosus B281 and P. membranifaciens M3A. Lactic acid bacteria (LAB) and yeasts were monitored on olives by plate counting for a period of 153 days, whereas the survival of the inoculated strains was confirmed by Pulsed Field Gel Electrophoresis (PFGE) and Restriction Fragment Length Polymorphism (RFLP) analysis. Inoculated fermentation with L. pentosus B281 with/without the presence of the yeast resulted in higher acidification of the brine compared to the spontaneous process where no indigenous LAB could be enumerated. The population of LAB on olives ranged between 5.5 and 6.5 log CFU/g and it was maintained at higher levels compared to yeasts (3.5-4.5 log CFU/g) throughout the process. PFGE analysis revealed that L. pentosus B281 could successfully colonize the surface of black olives presenting high recovery rate (100%) at the end of fermentation in contrast to P. membranifaciens M3A that was successfully recovered (42%) only after 72 days of the process. The obtained results provide interesting perspectives for the production of natural black olives with functional properties. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Technological Potential of Lactobacillus Strains Isolated from Fermented Green Olives: In Vitro Studies with Emphasis on Oleuropein-Degrading Capability

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    Massimo Iorizzo

    2016-01-01

    Full Text Available Technological properties of two strains of Lactobacillus plantarum (B3 and B11 and one of Lactobacillus pentosus (B4, previously isolated from natural fermented green olives, have been studied in vitro. Acidifying ability, salt, temperature, and pH tolerances of all strains were found in the range reported for similar strains produced in Italy and optimal growth conditions were found to be 6.0–8.0 pH, 15–30°C temperature, and less than 6% NaCl. Moreover, all strains showed very good tolerance to common olive phenol content (0.3% total phenol and high oleuropein-degrading capability. It was found that medium composition affected the bacterial oleuropein degradation. B11 strain grown in a nutrient-rich medium showed a lower oleuropein-degrading action than when it was cultivated in nutrient-poor medium. Furthermore, enzymatic activity assays revealed that oleuropein depletion did not correspond to an increase of hydroxytyrosol, evidencing that bacterial strains could efficiently degrade oleuropein via a mechanism different from hydrolysis.

  6. Antiproliferation effects and antioxidant activity of two new Lactobacillus strains

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    Parisa Shokryazdan

    2017-11-01

    Full Text Available Abstract The microorganisms most commonly used as probiotics are lactic acid bacteria, especially those of the genus Lactobacillus. In the present study, two Lactobacillus strains, L. pentosus ITA23 and L. acidipiscis ITA44, previously isolated from mulberry silage, were characterized for their antiproliferative and antioxidant activities. The antiproliferative effects of the strains were investigated using the MTT assay with breast cancer (MDA-MB-231, liver cancer (HepG2 and normal liver (Chang cell lines. The strains were tested for their antioxidant activity using the FRAP and ABTS methods. The results showed that the two Lactobacillus strains had good antiproliferative effects against both cancer cell lines tested, while their effects on the normal cells were weak. Based on the results of the antioxidant tests, the intact cells and cell-free extracts of the two Lactobacillus strains showed more than 135 and less than 50 µg trolox/ml of antioxidant activity, respectively. Lactobacillus pentosus ITA23 and L. acidipiscis ITA44 can be considered as potential probiotic candidates for humans because of their antioxidant activity and antiproliferation effects against cancer cells.

  7. Lactobacillus Pentosus Ita23 and L. Acidipiscis Ita44 Enhance Feed Conversion Efficiency and Beneficial Gut Microbiota in Broiler Chickens

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    YW Altaher

    2015-06-01

    Full Text Available Although the use of probiotics especially Lactobacillus and Bifidobacteria species on growth and feed utilization in poultry production has been extensively studied, the results were inconsistent presumably because the mode of action of probiotic is multi-factorial and each probiotic strain may affect the host in a specific manner. This study investigated the probiotic effect of two strains of Lactobacillus(Lactobacillus pentosus ITA23 and Lactobacillus acidophilus ITA44; 109 cells/kg feed isolated from mulberry (Morus Alba silage on the growth performance, cecal microbial population, and blood cholesterol of broiler chickens. One hundred twenty male broiler chicks (Cobb500 were randomLy allocated to two groups (control and treatment of six replicates (cages with 10 chicks per cage. Chicks in the control group received a standard diet and those in the treatment group received the same diet supplemented with 109 cells of the above Lactobacillus per kg feed. Supplementation of Lactobacillus did not affect body weight gain (averaged 1604 g at 35 days old but feed conversion ratio improved (p<0.01 by 6.4% due to reduction in feed intake (p<0.01 by birds in the treatment group. Supplementation also increased the population of Lactobacillusspp. and reduced pathogens E. coli in the cecal samples. Although Lactobacillus supplementation tends to reduce serum total cholesterol, low-density lipoprotein (LDL and triglyceride concentrations, these values were not significantly different from those of the control group. Results of this study showed that L. pentosus ITA23 and L. acidophilus ITA44 are potential probiotics to be used in poultry diets.

  8. Bacteriocin production by Lactobacillus pentosus ST712BZ isolated from boza Bacteriocina produzida por Lactobacillus pentosus ST712BZ isolad de boza

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    Svetoslav D. Todorov

    2007-03-01

    Full Text Available Bacteriocin ST712BZ (14.0kDa in size inhibits the growth of Lactobacillus casei,Escherichia coli, Pseudomonas aeruginosa,Enterococcus faecalis, Klebsiella pneumoniae and Lactobacillus curvatus. Growth of strain ST712BZ in BHI, M17, soy milk and molasses was similar to growth in MRS, with optimal bacteriocin production (12800AU/mL recorded in MRS after 24h. The same level of bacteriocin production (12800AU/mL was recorded in MRS broth with an initial pH of 6.5, 6.0 and 5.5. However, MRS broth (pH 6.5 supplemented with 1mM EDTA, yielded only 6400AU/mL. Low levels of bacteriocin activity were recorded in MRS broth with an initial pH of 5.0 and 4.5. Of all media compositions tested, MRS supplemented with tryptone (20.0g/L, glucose (20.0 to 40.0g/L, mannose (20.0g/L, vitamin B12, or vitamin C yielded 12800AU/mL. Glycerol concentrations of 1.0g/L and higher repressed bacteriocin production. Maximal bacteriocin activity (25600AU/mL was recorded in MRS supplemented with Vit. B1 or DL-6,8-thioctic acid.A bacteriocina ST712BZ produzida par Lactobacillus pentosus (peso molecular de 14,0kDa inibe o crescimento de Lactobacillus casei,Escherichia coli, Pseudomonas aeruginosa,Enterococcus faecalis, Klebsiella pneumoniae e Lactobacillus curvatus. O crescimento de L. pentosus ST712BZ em BHI, M17, leite de soja e melaços foi semelhante ao observado em MRS, registando-se a produção máxima de bacteriocina (12800UA/mL em MRS após 24 h. Observou-se o mesmo nível de produção de bacteriocina (12800UA/mL em caldo MRS com pH inicial de 6,5, 6,0 e 5,5. No entanto, em caldo MRS (pH 6,5 suplementado com 1 mM de EDTA a produção apenas atingiu 6400UA/mL. Os níveis de atividade bacteriocinogênica detectados em caldo MRS com um pH inicial de 5,0 e 4,5 foram baixos. De todas as fórmulas de meios de cultura testadas a que apresentou a atividade máxima 12800UA/mL foi MRS suplemento de triptona (20,0g/L, glicose (20,0 e 40,0 g/L, manose (20.0 g/L, vitamina B12 e

  9. Insight into Potential Probiotic Markers Predicted in Lactobacillus pentosus MP-10 Genome Sequence

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    Hikmate Abriouel

    2017-05-01

    Full Text Available Lactobacillus pentosus MP-10 is a potential probiotic lactic acid bacterium originally isolated from naturally fermented Aloreña green table olives. The entire genome sequence was annotated to in silico analyze the molecular mechanisms involved in the adaptation of L. pentosus MP-10 to the human gastrointestinal tract (GIT, such as carbohydrate metabolism (related with prebiotic utilization and the proteins involved in bacteria–host interactions. We predicted an arsenal of genes coding for carbohydrate-modifying enzymes to modify oligo- and polysaccharides, such as glycoside hydrolases, glycoside transferases, and isomerases, and other enzymes involved in complex carbohydrate metabolism especially starch, raffinose, and levan. These enzymes represent key indicators of the bacteria’s adaptation to the GIT environment, since they involve the metabolism and assimilation of complex carbohydrates not digested by human enzymes. We also detected key probiotic ligands (surface proteins, excreted or secreted proteins involved in the adhesion to host cells such as adhesion to mucus, epithelial cells or extracellular matrix, and plasma components; also, moonlighting proteins or multifunctional proteins were found that could be involved in adhesion to epithelial cells and/or extracellular matrix proteins and also affect host immunomodulation. In silico analysis of the genome sequence of L. pentosus MP-10 is an important initial step to screen for genes encoding for proteins that may provide probiotic features, and thus provides one new routes for screening and studying this potentially probiotic bacterium.

  10. Characterization of high exopolysaccharide-producing Lactobacillus strains isolated from mustard pickles for potential probiotic applications.

    Science.gov (United States)

    Huang, Jing-Yao; Kao, Cheng-Yen; Liu, We-Sin; Fang, Tony J

    2017-06-01

    The aim of this study was to characterize high exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) isolated from mustard pickles in Taiwan for potential probiotic applications. Among 39 collected LAB strains, four most productive EPS-producing strains were selected for further analysis. Comparative analyses of 16S rDNA genes rpoA and pheS sequences demonstrated that these strains were members of Lactobacillus plantarum-group (LPG). NCD 2, NLD 4, SLC 13, and NLD 16 showed survival rates of 95.83% ± 0.49%, 95.07% ± 0.64%, 105.84% ± 0.82%, and 99.65% ± 0.31% under simulated gastrointestinal conditions, respectively. No cytotoxic effects on macrophage RAW 264.7 cells were observed when they were treated with a low dose (1 μg/ml) of stimulants extracted from the tested LAB strains. The production of nitric oxide in RAW 264.7 cells incubated with various LAB stimulants showed a dose-dependent increase. Among the four strains, SLC 13 showed higher inhibitory activity on growth of Enterococcus faecalis (BCRC 12302) and Yersinia enterocolitica (BCRC 10807). NLD 4 showed strong inhibitory activity against Escherichia coli O157:H7 (ATCC 43894) as compared with the other three strains. In summary, our results suggest that Lactobacillus pentosus SLC 13 may be a good candidate for probiotic applications and for development of antibacterial compounds. [Int Microbiol 20(2):75-84 (2017)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  11. Ex situ treatment of hydrocarbon-contaminated soil using biosurfactants from Lactobacillus pentosus.

    Science.gov (United States)

    Moldes, Ana Belén; Paradelo, Remigio; Rubinos, David; Devesa-Rey, Rosa; Cruz, José Manuel; Barral, María Teresa

    2011-09-14

    The utilization of biosurfactants for the bioremediation of contaminated soil is not yet well established, because of the high production cost of biosurfactants. Consequently, it is interesting to look for new biosurfactants that can be produced at a large scale, and it can be employed for the bioremediation of contaminated sites. In this work, biosurfactants from Lactobacillus pentosus growing in hemicellulosic sugars solutions, with a similar composition of sugars found in trimming vine shoot hydrolysates, were employed in the bioremediation of soil contaminated with octane. It was observed that the presence of biosurfactant from L. pentosus accelerated the biodegradation of octane in soil. After 15 days of treatment, biosurfactants from L. pentosus reduced the concentration of octane in the soil to 58.6 and 62.8%, for soil charged with 700 and 70,000 mg/kg of hydrocarbon, respectively, whereas after 30 days of treatment, 76% of octane in soil was biodegraded in both cases. In the absence of biosurfactant and after 15 days of incubation, only 1.2 and 24% of octane was biodegraded in soil charged with 700 and 70,000 mg/kg of octane, respectively. Thus, the use of biosurfactants from L. pentosus, as part of a well-designed bioremediation process, can provide mechanisms to mobilize the target contaminants from the soil surface to make them more available to the microbial population.

  12. Diversity of lactic acid bacteria from Miang, a traditional fermented tea leaf in northern Thailand and their tannin-tolerant ability in tea extract.

    Science.gov (United States)

    Chaikaew, Siriporn; Baipong, Sasitorn; Sone, Teruo; Kanpiengjai, Apinun; Chui-Chai, Naradorn; Asano, Kozo; Khanongnuch, Chartchai

    2017-09-01

    The microbiota of lactic acid bacteria (LAB) in thirty-five samples of Miang, a traditional fermented tea leaf product, collected from twenty-two different regions of eight provinces in upper northern Thailand was revealed through the culture-dependent technique. A total of 311 presumptive LAB strains were isolated and subjected to clustering analysis based on repetitive genomic element-PCR (rep-PCR) fingerprinting profiles. The majority of the strains belonged to the Lactobacillus genera with an overwhelming predominance of the Lb. plantarum group. Further studies of species-specific PCR showed that 201 of 252 isolates in the Lb. plantarum group were Lb. plantarum which were thus considered as the predominant LAB in Miang, while the other 51 isolates belonged to Lb. pentosus. In contrast to Lb. plantarum, there is a lack of information on the tannase gene and the tea tannin-tolerant ability of Lb. pentosus. Of the 51 Lb. pentosus isolates, 33 were found to harbor the genes encoding tannase and shared 93-99% amino acid identity with tannase obtained from Lb. pentosus ATCC 8041 T . Among 33 tannase gene-positive isolates, 23 isolates exhibited high tannin- tolerant capabilities when cultivated on de Man Rogosa and Sharpe agar-containing bromocresol purple (0.02 g/L, MRS-BCP) supplemented with 20% (v/v) crude tea extract, which corresponded to 2.5% (w/v) tannins. These Lb. pentosus isolates with high tannin-tolerant capacity are expected to be the high potential strains for functional tannase production involved in Miang fermentation as they will bring about certain benefits and could be used to improve the fermentation of tea products.

  13. Optimization of nutritional and non-nutritional factors involved for production of antimicrobial compounds from Lactobacillus pentosus SJ65 using response surface methodology

    Directory of Open Access Journals (Sweden)

    Appukuttan Saraniya

    2014-01-01

    Full Text Available Bacteriocins from lactic acid bacteria are ribosomal synthesized antibacterial proteins/ peptides having wide range of applications. Lactobacillus pentosus SJ65, isolated from fermented Uttapam batter (used to prepare south Indian pan cake, produces bacteriocin having a broad spectrum of activity against pathogens. Optimization studies are of utmost important to understand the source of utilization and the conditions to enhance the production of metabolites. In the present study, an attempt was made to identify the parameters involved for maximal production of antimicrobial compounds especially bacteriocin from the isolate L. pentosus SJ65. Initially, optimal conditions, such as incubation period, pH, and temperature were evaluated. Initial screening was done using methodology onevariable-at-a-time (OVAT for various carbon and nitrogen sources. Further evaluation was carried out statistically using Plackett-Burman design and the variables were analyzed using response surface methodology using central composite design. The optimum media using tryptone or soy peptone, yeast extract, glucose, triammonium citrate, MnSO4, dipotassium hydrogen phosphate and tween 80 produced maximum bacteriocin activity.

  14. Molecular Detection of Two Potential Probiotic Lactobacilli Strains and Evaluation of Their Performance as Starter Adjuncts in Yogurt Production.

    Science.gov (United States)

    Saxami, Georgia; Papadopoulou, Olga S; Chorianopoulos, Nikos; Kourkoutas, Yiannis; Tassou, Chrysoula C; Galanis, Alex

    2016-05-04

    A molecular method for efficient and accurate detection and identification of two potential probiotic lactobacilli strains isolated from fermented olives, namely Lactobacillus pentosus B281 and Lb. plantarum B282, was developed in the present study. Random Amplified Polymorphic DNA (RAPD) analysis was performed, and strain specific primers were designed and applied in a multiplex polymerase chain reaction (PCR) assay. The specificity of the assay was tested and successfully confirmed in 27 and 22 lactobacilli strains for Lb. pentosus B281 and Lb. plantarum B282, respectively. Moreover, the two strains were used as starter cultures in yogurt production. Cell enumeration followed by multiplex PCR analysis demonstrated that the two strains were present in yogurt samples at levels ≥6 log CFU/g even after 35 days of storage at 4 °C. Microbiological analysis showed that lactobacilli and streptococci were present within usual levels, whereas enterobacteriaceae and yeast/mold counts were not detected as expected. Although the pH values of the novel products were slightly lower than the control ones, the yogurt containing the probiotic cultures scored similar values compared to the control in a series of sensory tests. Overall, these results demonstrated the possible use of the two strains as starter adjuncts in the production of yogurt with potential probiotic properties.

  15. Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

    Science.gov (United States)

    Fei, Yong-tao; Liu, Dong-mei; Luo, Tong-hui; Chen, Gu; Wu, Hui; Li, Li; Yu, Yi-gang

    2014-01-01

    Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (PLactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively) of the L-lactate dehydrogenase 1 (L-ldh1) gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

  16. Probiotic properties of endemic strains of lactic acid bacteria

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    Flora N. Tkhruni

    2013-01-01

    Full Text Available Strains of lactic acid bacteria (LAB isolated from various samples of matsun, yogurt and salted cheese from natural farms of Armenia were studied. They have high antimicrobial and probiotic activities, growth rate and differ by their resistance to enzymes. Supernatants of LAB retain bactericidal activity at рН 3.0-8.0 and inhibit growth of various microflora. The application of different methods of identification and LAB genotyping (API 50 CH, 16S rRNA sequencing, GS-PCR, RAPD PCR showed that isolated LAB evidenced a 99.9% similarity with L. rhamnosus, L. plantarum and L. pentosus species and coccoid forms of Streptococcus and Enterococcus species. It can be concluded, that some strains of lactic acid bacteria, isolated from dairy products from natural farms of Armenia, can be properly used for biopreservation of some foodstuffs. On the basis of experimental data, the LAB can be used as basis for obtaining the new products of functional nutrition.

  17. Molecular Detection of Two Potential Probiotic Lactobacilli Strains and Evaluation of Their Performance as Starter Adjuncts in Yogurt Production

    Directory of Open Access Journals (Sweden)

    Georgia Saxami

    2016-05-01

    Full Text Available A molecular method for efficient and accurate detection and identification of two potential probiotic lactobacilli strains isolated from fermented olives, namely Lactobacillus pentosus B281 and Lb. plantarum B282, was developed in the present study. Random Amplified Polymorphic DNA (RAPD analysis was performed, and strain specific primers were designed and applied in a multiplex polymerase chain reaction (PCR assay. The specificity of the assay was tested and successfully confirmed in 27 and 22 lactobacilli strains for Lb. pentosus B281 and Lb. plantarum B282, respectively. Moreover, the two strains were used as starter cultures in yogurt production. Cell enumeration followed by multiplex PCR analysis demonstrated that the two strains were present in yogurt samples at levels ≥6 log CFU/g even after 35 days of storage at 4 °C. Microbiological analysis showed that lactobacilli and streptococci were present within usual levels, whereas enterobacteriaceae and yeast/mold counts were not detected as expected. Although the pH values of the novel products were slightly lower than the control ones, the yogurt containing the probiotic cultures scored similar values compared to the control in a series of sensory tests. Overall, these results demonstrated the possible use of the two strains as starter adjuncts in the production of yogurt with potential probiotic properties.

  18. Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

    Directory of Open Access Journals (Sweden)

    Yong-tao Fei

    Full Text Available Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010 was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (P<0.001. Based on 16S rDNA sequencing and sequence comparison, Lactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively of the L-lactate dehydrogenase 1 (L-ldh1 gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

  19. Genotypic diversity of stress response in Lactobacillus plantarum, Lactobacillus paraplantarum and Lactobacillus pentosus.

    Science.gov (United States)

    Ricciardi, Annamaria; Parente, Eugenio; Guidone, Angela; Ianniello, Rocco Gerardo; Zotta, Teresa; Abu Sayem, S M; Varcamonti, Mario

    2012-07-02

    Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus paraplantarum are three closely related species which are widespread in food and non-food environments, and are important as starter bacteria or probiotics. In order to evaluate the phenotypic diversity of stress tolerance in the L. plantarum group and the ability to mount an adaptive heat shock response, the survival of exponential and stationary phase and of heat adapted exponential phase cells of six L. plantarum subsp. plantarum, one L. plantarum subsp. argentoratensis, one L. pentosus and two L. paraplantarum strains selected in a previous work upon exposure to oxidative, heat, detergent, starvation and acid stresses was compared to that of the L. plantarum WCFS1 strain. Furthermore, to evaluate the genotypic diversity in stress response genes, ten genes (encoding for chaperones DnaK, GroES and GroEL, regulators CtsR, HrcA and CcpA, ATPases/proteases ClpL, ClpP, ClpX and protease FtsH) were amplified using primers derived from the WCFS1 genome sequence and submitted to restriction with one or two endonucleases. The results were compared by univariate and multivariate statistical methods. In addition, the amplicons for hrcA and ctsR were sequenced and compared by multiple sequence alignment and polymorphism analysis. Although there was evidence of a generalized stress response in the stationary phase, with increase of oxidative, heat, and, to a lesser extent, starvation stress tolerance, and for adaptive heat stress response, with increased tolerance to heat, acid and detergent, different growth phases and adaptation patterns were found. Principal component analysis showed that while heat, acid and detergent stresses respond similarly to growth phase and adaptation, tolerance to oxidative and starvation stresses implies completely unrelated mechanisms. A dendrogram obtained using the data from multilocus restriction typing (MLRT) of stress response genes clearly separated two groups of L

  20. Use of the RAPD-PCR fingerprinting and API system for clustering ...

    African Journals Online (AJOL)

    These were Lactobacillus delbreuckii supsp bulgaricus (one strain), Lactobacillus rhamnosus (nine strains), and lactobacillus plantarum (two strains), Lactobacillus casei (one strain) and Lactobacillus pentosus (one strain). The 28 coccal isolates were separated into nine clusters, the representative strains of which were ...

  1. Methods for the evaluation of antibiotic resistance in Lactobacillus isolated from fermented sausages

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    Hanna Lethycia Wolupeck

    Full Text Available ABSTRACT: The present study aimed to assess the antibiotic resistance in 54 indigenous Lactobacillus plantarum isolated from artisanal fermented sausages. The confirmation of the strain species was performed by multiplex-PCR assay. Antibiotic resistance was assessed by disk diffusion (DD and Minimum Inhibitory Concentration (MIC methods. Of 54 L. plantarum, 44 strains were genotypically confirmed as L. plantarum and 3 as Lactobacillus pentosus. The highest resistance rates were to ampicillin and streptomycin. The highest susceptibility rates were shown to tetracycline, chloramphenicol and penicillin G. None of the strains showed multidrug resistance. Resistance rates by DD and MIC were not different (P>0.05 for ampicillin, chloramphenicol, erythromycin and penicillin G. Future research should assess the genetic mechanisms underlying the phenotypic resistance in Lactobacillus strains to screen the potential probiotic strains for the development of functional meat products.

  2. The mechanism of Lactobacillus strains for their ability to remove fumonisins B1 and B2.

    Science.gov (United States)

    Zhao, Hongfei; Wang, Xiao; Zhang, Junwen; Zhang, Jun; Zhang, Bolin

    2016-11-01

    Two Lactobacillus strains, L. plantarum B7 and L. pentosus X8, exhibited high efficiency in removing fumonisins (FB1 and FB2) from aqueous medium. 52.9% FB1 and 85.2% FB2 were bound by L. plantarum B7, and 58.0% FB1 and 86.5% FB2 by L. pentosus X8, respectively. Temperature, incubation time, and pH affected the binding ability of two strains. Cell viability was not necessary for the binding ability. The various components of cell wall were determined for their ability to absorb FBS. The results revealed that the intact peptidoglycans exhibited the greatest capacity in binding FBs. Especially the better structural integrity of the peptidoglycans the more FBs was bound. Thus, the absorption of two bacterial cells to FBs is proposed to be a physical process, and peptidoglycans should be the main binding site. Additionally, Caco-2 cell lines were used to evaluate the ability of the two strains to reduce the damage of FBs in vitro. Caco-2 cell's death was reduced after the cell lines were subjected to both viable and non-viable L. pentosus X8, respectively. The two Lactobacillus strains might be used as a biological detoxification for the removal of FBs from diet and feed in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests.

    Science.gov (United States)

    Argyri, Anthoula A; Zoumpopoulou, Georgia; Karatzas, Kimon-Andreas G; Tsakalidou, Effie; Nychas, George-John E; Panagou, Efstathios Z; Tassou, Chrysoula C

    2013-04-01

    The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei subsp. paracasei) isolated from table olives were screened for their probiotic potential. Lb. rhamnosus GG and Lb. casei Shirota were used as reference strains. The in vitro tests included survival in simulated gastrointestinal tract conditions, antimicrobial activity (against Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7), Caco-2 surface adhesion, resistance to 9 antibiotics and haemolytic activity. Three (3) Lb. pentosus, 4 Lb. plantarum and 2 Lb. paracasei subsp. paracasei strains demonstrated the highest final population (>8 log cfu/ml) after 3 h of exposure at low pH. The majority of the tested strains were resistant to bile salts even after 4 h of exposure, while 5 Lb. plantarum and 7 Lb. pentosus strains exhibited partial bile salt hydrolase activity. None of the strains inhibited the growth of the pathogens tested. Variable efficiency to adhere to Caco-2 cells was observed. This was the same regarding strains' susceptibility towards different antibiotics. None of the strains exhibited β-haemolytic activity. As a whole, 4 strains of Lb. pentosus, 3 strains of Lb. plantarum and 2 strains of Lb. paracasei subsp. paracasei were found to possess desirable in vitro probiotic properties similar to or even better than the reference probiotic strains Lb. casei Shirota and Lb. rhamnosus GG. These strains are good candidates for further investigation both with in vivo studies to elucidate their potential health benefits and in olive fermentation processes

  4. Genotypic and phenotypic characterization of garlic-fermenting lactic acid bacteria isolated from som-fak, a Thai low-salt fermented fish product

    DEFF Research Database (Denmark)

    Paludan-Müller, Christine; Valyasevi, R.; Huss, Hans Henrik

    2002-01-01

    AIMS: To evaluate the importance of garlic for fermentation of a Thai fish product, and to differentiate among garlic-/inulin-fermenting lactic acid bacteria (LAB) at strain level. METHODS AND RESULTS: Som-fak was prepared by fermentation of a mixture of fish, salt, rice, sucrose and garlic. p......H decreased to 4.5 in 2 days, but omitting garlic resulted in a lack of acidification. LAB were predominant and approximately one third of 234 isolated strains fermented garlic and inulin (the carbohydrate reserve in garlic). These strains were identified as Lactobacillus pentosus and Lact. plantarum...... AND IMPACT OF THE STUDY: The present study indicates the role of fructans (garlic/inulin) as carbohydrate sources for LAB. Fructan fermenters may have several biotechnological applications, for example, as probiotics....

  5. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    Directory of Open Access Journals (Sweden)

    A. B. Moldes

    2013-01-01

    Full Text Available The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-. The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage, as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment.

  6. Partial Characterization of Biosurfactant from Lactobacillus pentosus and Comparison with Sodium Dodecyl Sulphate for the Bioremediation of Hydrocarbon Contaminated Soil

    Science.gov (United States)

    Moldes, A. B.; Paradelo, R.; Vecino, X.; Cruz, J. M.; Gudiña, E.; Rodrigues, L.; Teixeira, J. A.; Domínguez, J. M.; Barral, M. T.

    2013-01-01

    The capability of a cell bound biosurfactant produced by Lactobacillus pentosus, to accelerate the bioremediation of a hydrocarbon-contaminated soil, was compared with a synthetic anionic surfactant (sodium dodecyl sulphate SDS-). The biosurfactant produced by the bacteria was analyzed by Fourier transform infrared spectroscopy (FTIR) that clearly indicates the presence of OH and NH groups, C=O stretching of carbonyl groups and NH nebding (peptide linkage), as well as CH2–CH3 and C–O stretching, with similar FTIR spectra than other biosurfactants obtained from lactic acid bacteria. After the characterization of biosurfactant by FTIR, soil contaminated with 7,000 mg Kg−1 of octane was treated with biosurfactant from L. pentosus or SDS. Treatment of soil for 15 days with the biosurfactant produced by L. pentosus led to a 65.1% reduction in the hydrocarbon concentration, whereas SDS reduced the octane concentration to 37.2% compared with a 2.2% reduction in the soil contaminated with octane in absence of biosurfactant used as control. Besides, after 30 days of incubation soil with SDS or biosurfactant gave percentages of bioremediation around 90% in both cases. Thus, it can be concluded that biosurfactant produced by L. pentosus accelerates the bioremediation of octane-contaminated soil by improving the solubilisation of octane in the water phase of soil, achieving even better results than those reached with SDS after 15-day treatment. PMID:23691515

  7. Fortification of table olive packing with the potential probiotic bacteria Lactobacillus pentosus TOMC-LAB2

    Directory of Open Access Journals (Sweden)

    Francisco Rodriguez Gomez

    2014-09-01

    Full Text Available Dairy products are currently the main carriers of probiotic microorganisms to the human body. However, the development of new matrices for probiotic delivery is convenient for intolerant to milk (or its derivatives and those requiring low-cholesterol diet consumers. The present work focused on the fortification of previously fermented green Spanish style olives with the autochthonous putative probiotic bacteria Lactobacillus pentosus TOMC-LAB2. The fortification was carried out by inoculating the bacteria into the packing brines using Manzanilla fruits from three different processes: i spontaneously fermented (F1, ii fermented using L. pentosus TOMC-LAB2 as starter (F2, and iii spontaneously fermented and then thermally treated (F3. Data showed that all inoculated treatments had higher population levels (5.49, 4.41 and 6.77 log10 cfu/cm2 than their respective controls (1.66, 4.33 and 0.0 log10 cfu/cm2, for F1, F2 and F3 treatments, respectively. The presence of L. pentosus TOMC-LAB2 on olive surface was confirmed by rep-PCR, with a recovery frequency at the end of the shelf life (200 days of 52.6, 57.9 and 100.0% for F1, F2 and F3 treatments, respectively. Thus, results obtained in this work show the ability of this microorganism to survive under packing conditions for long period of times as well as to colonize the olive surface which is the food finally ingested by consumers. This opens the possibility for the development of a new and simply probiotic fortified olive product.

  8. Isolation of tannin-degrading lactobacilli from humans and fermented foods.

    Science.gov (United States)

    Osawa, R; Kuroiso, K; Goto, S; Shimizu, A

    2000-07-01

    Lactobacilli with tannase activity were isolated from human feces and fermented foods. A PCR-based taxonomic assay revealed that the isolates belong to Lactobacillus plantarum, L. paraplantarum, and L. pentosus. Additional studies on a range of Lactobacillus species from established culture collections confirmed that this enzymatic activity is a phenotypic property common to these three species.

  9. Cloning, sequence analysis, and characterization of the genes involved in isoprimeverose metabolism in Lactobacillus pentosus

    NARCIS (Netherlands)

    Chaillou, S.; Lokman, B.C.; Leer, R.J.; Posthuma, C.; Postma, P.W.; Pouwels, P.H.

    1998-01-01

    Two genes, xylP and xylQ, from the xylose regulon of Lactobacillus pentosus were cloned and sequenced. Together with the repressor gene of the regulon, xylR, the xylPQ genes form an operon which is inducible by xylose and which is transcribed from a promoter located 145 bp upstream of xylP. A

  10. Evaluation of Antimicrobial Activity of Bacillus Strains Isolated from Various Resources

    Directory of Open Access Journals (Sweden)

    Mohsen Golnari Maranni

    2017-02-01

    Full Text Available Abstract Background: Prevalence extension of antibiotic resistant bacteria has raised concerns about control of infections especially nosocomial infections. Many attempts have been done to replace antibiotics or limit their use. The use of antimicrobial agents produced by bacteria as antibiotic replacement has been promising in recent years. The goal of this study was to isolate Bacillus strains and evaluate their antimicrobial activity against some standard pathogens and clinical antibiotic resistant strains. Materials and Methods: In the present study, Bacillus strains were isolated from various resources and identified by 16S rDNA PCR method. Then, the phylogenetic tree of the isolates was constructed and antimicrobial activity of the isolates was investigated against some standard pathogens and clinical antibiotic resistant strains using spotting and well diffusion methods. Results: Eight Bacillus strains were isolated from 15 different samples. Based on the molecular identification, the isolates were identified as B.pumilus, B.coagulans, B.licheniformis, B.endophitycus and B.amiloliquefaciens. The results showed that isolates have antimicrobial activity against meticilin-resistant Staphylococcus aureus, vancomycin resistant enterococci, Klebsiella, Acinetobacter, Salmonella, Shigella, Listeria, Streptococcus and Escherichia coli. Conclusion: In this study, isolated Bacillus strains produced antimicrobial agents against pathogens and antibiotic resistant strains and inhibited their growth.

  11. Shewanella strain isolated from black powder

    Energy Technology Data Exchange (ETDEWEB)

    Lutterbach, Marcia T.S.; Contador, Luciana S.; Oliveira, Ana Lucia C.; Galvao, Mariana M. [National Institute of Technology (INT), Rio de Janeiro, RJ (Brazil); Pimenta, Gutemberg S. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Black powder is a term frequently used to refer to residues formed by various types of iron sulfides mixed with contaminants eventually present in the natural gas flow. According to some researchers, the occurrence of black powder in gas pipelines, besides its chemical corrosion origin, can be directly related to the sulfate-reducing bacteria (SRB) metabolism in this environment. A black powder sample was inoculated in a Post gate E medium modified with the addition of thioglycolate. The resulting positive culture was kept in the laboratory for four years until its use. A dilution technique was then performed aiming to isolate an SRB strain. The bacterial strain isolated and identified through DNA sequencing was not an SRB but rather a Shewanella sp. Compared to the sulfate-reducing bacteria group-traditionally considered the foremost responsible for microbially-influenced corrosion (MIC) - Shewanella is a facultative anaerobe and has a versatile metabolism. Shewanella is able to reduce ferric iron and sulfite, oxidize hydrogen gas, and produce hydrogen sulfide; therefore, these bacteria can be responsible for MIC and pit formation. The isolated Shewanella was used in a corrosion experiment, and the corrosion products were characterized by X-ray diffraction, identifying iron sulfides, iron oxides, and sulfur. Our results indicate that the strain isolated, S. putrefaciens, plays a key role in corrosion problems in gas pipelines. (author)

  12. Isolation and purification of Gallid herpesvirus 2 strains currently distributed in Japan.

    Science.gov (United States)

    Machida, Yuka; Murata, Shiro; Matsuyama-Kato, Ayumi; Isezaki, Masayoshi; Taneno, Akira; Sakai, Eishi; Konnai, Satoru; Ohashi, Kazuhiko

    2017-01-20

    Gallid herpesvirus 2 (GaHV-2) causes malignant lymphomas in chickens (Marek's disease, MD). Although MD is controlled through vaccination efforts, field isolates of GaHV-2 have increased in virulence worldwide and even cause MD in vaccinated chickens. GaHV-2 strains are classified into four categories (mild, virulent, very virulent and very virulent +) based on the virulence exhibited in experimental infection in unvaccinated or MD-vaccinated susceptible chickens. Although MD cases are sporadically reported in Japan, the recent field strains of GaHV-2 in Japan have not been characterized. During isolation of recent field strains by using primary chicken kidney cell cultures, a method classically used for GaHV-2 isolation, vaccine strains were simultaneously isolated. Therefore, it is necessary to separate vaccine strains to characterize the virulence and pathogenicity of the GaHV-2 strains currently distributed in Japan. In this study, we prepared cell suspensions from the spleens of MD-symptomatic chickens, inoculated day-old-chicks and isolated GaHV-2 strains by primary chicken kidney cell cultures at 2-3 weeks post inoculation. The isolated strains were passaged several times on chicken embryo fibroblast cells, and PCR analysis revealed that the isolated strains were not contaminated with vaccine strains. Moreover, the contaminant vaccine strains were completely removed by the purification of plaques observed in chicken kidney cells. These procedures are necessary to isolate GaHV-2 field strains from vaccine strains in order to carry out future studies to characterize these strains and glean insights into GaHV-2 virulence and pathogenicity.

  13. Genetic variations among Mycoplasma bovis strains isolated from Danish cattle

    DEFF Research Database (Denmark)

    Kusiluka, L.J.M.; Kokotovic, Branko; Ojeniyi, B.

    2000-01-01

    The genetic heterogeneity of Mycoplasma bovis strains isolated in Denmark over a 17-year period was investigated. Forty-two field strains isolated from different geographic locations and specimens, including strains from 21 herds involved in two outbreaks of M. bovis-induced mastitis, and the type...

  14. Characterization of lactic acid bacteria isolated from a Thai low-salt fermented fish product and the role of garlic as substrate for fermentation

    DEFF Research Database (Denmark)

    Paludan-Müller, Christine; Huss, Hans Henrik; Gram, Lone

    1999-01-01

    associated with fish fillet and minced fish, Lactobacillus paracasei subsp. paracasei with boiled rice and Weisella confusa with garlic mix and banana leaves. In addition, Lactobacillus plantarum, Lactobacillus pentosus and Pediococcus pentosaceus were isolated from raw materials. A succession of aciduric......Lactic acid bacteria (LAB) isolated from raw materials (fish, rice, garlic and banana leaves) and processed som-fak (a Thai low-salt fermented fish product) were characterized by API 50- CH and other phenotypic criteria. Lactococcus lactis subsp. lactis and Leuconostoc citreum were specifically....... paracasei, or garlic fermenting Lb. plantarum and Pd. pentosaceus, or a combination of these strains were inoculated into laboratory prepared som-fak with or without garlic. In som-fak without garlic, pH was above 4.8 after three days, irrespective of addition of mixed LAB cultures. The starch fermenting...

  15. Identification of lactobacilli with inhibitory effect on biofilm formation by pathogenic bacteria on stainless steel surfaces.

    Science.gov (United States)

    Ait Ouali, Fatma; Al Kassaa, Imad; Cudennec, Benoit; Abdallah, Marwan; Bendali, Farida; Sadoun, Djamila; Chihib, Nour-Eddine; Drider, Djamel

    2014-11-17

    Two hundred and thirty individual clones of microorganisms were recovered from milk tanks and milking machine surfaces at two distinct farms (Bejaja City, Algeria). Of these clones, 130 were identified as lactic acid bacteria (LAB). In addition Escherichia coli, Salmonella, Staphylococcus aureus and Pseudomonas aeruginosa species were identified in the remaining 100 isolates-spoilage isolate. These isolates were assayed for ability to form biofilms. S. aureus, Lactobacillus brevis strains LB1F2, LB14F1 and LB15F1, and Lactobacillus pentosus strains LB2F2 and LB3F2 were identified as the best biofilm formers. Besides, these LAB isolates were able to produce proteinaceous substances with antagonism against the aforementioned spoilage isolates, when grown in MRS or TSB-YE media. During the screening, L. pentosus LB3F2 exhibited the highest antibacterial activity when grown in TSB-YE medium at 30 °C. Additionally, L. pentosus LB3F2 was able to strongly hamper the adhesion of S. aureus SA3 on abiotic surfaces as polystyrene and stainless steel slides. LAB isolates did not show any hemolytic activity and all of them were sensitive to different families of antibiotic tested. It should be pointed out that LB3F2 isolate was not cytotoxic on the intestinal cells but could stimulate their metabolic activity. This report unveiled the potential of LB1F2, LB14F1, LB15F1, LB2F2, and LB3F2 isolates to be used as natural barrier or competitive exclusion organism in the food processing sector as well as a positive biofilm forming bacteria. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Phylogenetic analysis of Hungarian goose parvovirus isolates and vaccine strains.

    Science.gov (United States)

    Tatár-Kis, Tímea; Mató, Tamás; Markos, Béla; Palya, Vilmos

    2004-08-01

    Polymerase chain reaction and sequencing were used to analyse goose parvovirus field isolates and vaccine strains. Two fragments of the genome were amplified. Fragment "A" represents a region of VP3 gene, while fragment "B" represents a region upstream of the VP3 gene, encompassing part of the VP1 gene. In the region of fragment "A" the deduced amino acid sequence of the strains was identical, therefore differentiation among strains could be done only at the nucleotide level, which resulted in the formation of three groups: Hungarian, West-European and Asian strains. In the region of fragment "B", separation of groups could be done by both nucleotide and deduced amino acid sequence level. The nucleotide sequences resulted in the same groups as for fragment "A" but with a different clustering pattern among the Hungarian strains. Within the "Hungarian" group most of the recent field isolates fell into one cluster, very closely related or identical to each other, indicating a very slow evolutionary change. The attenuated strains and field isolates from 1979/80 formed a separate cluster. When vaccine strains and field isolates were compared, two specific amino acid differences were found that can be considered as possible markers for vaccinal strains. Sequence analysis of fragment "B" seems to be a suitable method for differentiation of attenuated vaccine strains from virulent strains. Copyright 2004 Houghton Trust Ltd

  17. The isolation, characterization and evaluation of Frankia strains

    Energy Technology Data Exchange (ETDEWEB)

    Normand, P.; Lalonde, M.; Fortin, J.A.; Chatarpaul, L.

    1984-01-01

    Osmium tetroxide (OsO/sub 4/) was used as the sterilizing agent to isolate the nitrogen-fixing endophyte Frankia from nodules of host plants. This treatment resulted in a pure culture collection of 250 Frankia isolates from several species of Alnus (crispa, rugosa, viridis, glutinosa, and serrulata) and from other actinorhizal species from Quebec. Frankia isolates from A. viridis and S. canadensis are reported in this document for the first time. Sugars from whole-cell hydrolysates of the organisms were analysed by gas liquid chromatography to identify strains previously screened on the basis of morphology and infectivity. This technique proved especially useful for those isolates whose morphology was atypical (ACN8, ArgN22, SCN9, and SCN10). It was demonstrated that sugar analysis (2-O-methy-D-mannose, in particular) can be important in resolving the taxonomy of Frankia. The nitrogen-fixing efficiency of some Frankia strains was evaluated by inoculating A. crispa. It was found that the efficiency of organisms was not influenced by the host from which they were first isolated. However, significant differences between some isolates of the same provenance occurred. It was also found that those strains of Frankia which do not sporulate were more effective in fixing nitrogen than those which do. It is proposed that the terms type P and type N be used to designate spore positive (Sp/sup +/) and spore negative (Sp/sup -/) Frankia strains, respectively. Further, it is recommended that sporulation type be used as a valid basis for species definition in the genus Frankia. 118 refs., 16 figs., 10 tabs.

  18. Antimicrobial Resistance of Staphylococcal Strains Isolated from Various Pathological Products

    Directory of Open Access Journals (Sweden)

    Laura-Mihaela SIMON

    2010-12-01

    Full Text Available Background: The optimal choice of antimicrobial therapy is an important problem in hospital environment in which the selection of resistant and virulent strains easy occurs. S. aureus and especially MRSA(methicillin-resistant S. aureus creates difficulties in both treatment and prevention of nosocomial infections. Aim: The purpose of this study is to determine the sensitivity and the resistance to chemotherapy of staphylococci strains isolated from various pathological products. Material and Method: We identified Staphylococccus species after morphological appearance, culture properties, the production of coagulase, hemolisines and the enzyme activity. The susceptibility tests were performed on Mueller-Hinton medium according to CLSI (Clinical and Laboratory Standards Institute. Results: The strains were: MSSA (methicillin-susceptible S. aureus (74%, MRSA (8%, MLS B (macrolides, lincosamides and type B streptogramines resistance (12% and MRSA and MLS B (6%. MRSA strains were more frequently isolated from sputum. MRSA associated with the MLS B strains were more frequently isolated from pus. MLS B strains were more frequently isolated from sputum and throat secretions. All S. aureus strains were susceptible to vancomycin and teicoplanin. Conclusions: All staphylococcal infections require resistance testing before treatment. MLS B shows a high prevalence among strains of S. aureus. The association between MLS B and MRSA remains a major problem in Romania.

  19. Fusidic acid resistance among staphylococci strains isolated from clinical specimens

    Directory of Open Access Journals (Sweden)

    Özcan Deveci

    2012-03-01

    Full Text Available Objectives: The aim of this study was to investigate in vitrosusceptibility of fusidic acid to clinic isolates of staphylococci.Materials and methods: The forty-one coagulase negativestaphylococci (CNS and 18 Staphylococcus aureusstrains isolated from various clinical specimens were includedin this study. Staphylococci isolates were identifiedby conventional methods such as colony morphologyonto medium, gram staining, catalase and coagulasetests. According to “Clinical and Laboratory Standards Institute(CLSI” criteria, antimicrobial susceptibility testingof isolates was performed by Kirby-Bauer’s disk diffusionmethod.Results: The seventy-two percent of the isolated S.aureuswere defined as methicillin sensitive-S.aureus (MSSA,28% of the isolated S.aureus were defined as methicillinresistant-S.aureus (MRSA. The difference among fusidicacid susceptibility rates of MSSA and MRSA strains wasnot statistically significant (p=0.305. The twenty-nine percentof the isolated CNS were defined as methicillin sensitive-CNS (MS-CNS, 71% of the isolated CNS were definedas methicillin resistant-CNS (MR-CNS. There wasno statistically significant difference between MS-CNSand MR-CNS strains for fusidic acid susceptibility rates(p=0.490. But the difference among fusidic acid susceptibilityrates of CNS and S.aureus strains was statisticallysignificant (p<0.001. CNS strains were found more resistancethan S.aureus strains for fusidic acid.Conclusion: In this study, the resistance rates weredetected to increase for fusidic acid along with methicillinresistance. Among CNS isolates, fusidic acid resistancerates were significantly more elevated than that forS.aureus. Fusidic acid remains as an alternative in thetreatment of infections due to staphylococci.

  20. Isolation and Identification of L-asparaginase producing Erwinia strains which isolated from Potato Farms

    Directory of Open Access Journals (Sweden)

    Arastoo Badoei-Dalfard

    2016-09-01

    Full Text Available Introduction: L-Asparaginase can be effectively used for the treatment of lymphoblastic leukemia. The rapid growth of cancer cells are needed for L-asparagine abundant storage. L-asparaginase catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. The purpose of this study was to isolate and identify the L-asparaginase producing Erwinia strains from the potato farms of Jiroft. Materials and methods: Pectolytic Erwinia species isolated from crumbling potato in M9 medium. The desired L-asparaginase producing bacteria were isolated based on the color changes. Biochemical-microbial and the plant pathogenicity tests of these strains were also investigated with potato and geranium. The L-asparaginase production and molecular detection of these Erwinia strains were also investigated. Results: In this study, L-asparaginase producing Erwinia was isolated on the CVP and M9 mediums. The inoculation of Erwinia strains on the potato and geranium plants showed that Er8 and Er11 species have the ability to cause plant pathogenicity. Results showed that the maximum pathogenicity of Er8 and Er11 was observed after 48 and 15 h of inoculation in potato and geranium plants, respectively. 16S rDNA sequencing and phylogenetic analyses exhibited that Er8 and Er11 strains were similar to Erwinia chrysanthemi with 98% homology. Discussion and conclusion: Because of several applications of the Erwinia L-asparaginase in various fields, isolated Erwinia and their L-asparaginase can be suitable for applied utilization.

  1. Feather wastes digestion by new isolated strains Bacillus sp. in ...

    African Journals Online (AJOL)

    Feather wastes digestion by new isolated strains Bacillus sp. in Morocco. ... The most efficient isolated strain selected was compared with Bacillus subtilis ATCC 6633. Results showed ... African Journal of Biotechnology Vol.3(1) 2004: 67-70 ...

  2. Biodiversity of Lactobacillus sanfranciscensis strains isolated from five sourdoughs.

    Science.gov (United States)

    Kitahara, M; Sakata, S; Benno, Y

    2005-01-01

    Five different sourdoughs were investigated for the composition of lactic acid bacteria (LAB) and the biodiversity of Lactobacillus sanfranciscensis strains. A total of 57 strains were isolated from five sourdoughs. Isolated strains were all identified by the 16S rDNA sequence and species-specific primers for L. sanfranciscensis. Results of identification showed that LAB strains were L. sanfranciscensis, Lactobacillus plantarum, Lactobacillus paralimentarius, Lactobacillus fermentum, Lactobacillus pontis, Lactobacillus casei, Weisella confusa and Pediococcus pentosaceus. A total of 21 strains were identified as L. sanfranciscensis and these isolates were detected in all five sourdoughs. Ribotyping was applied to investigate the relationship between intraspecies diversity of L. sanfranciscensis and sourdough. A total of 22 strains of L. sanfranciscensis including L. sanfranciscensis JCM 5668T were compared by ribotyping. The dendrogram of 21 ribotyping patterns showed four clusters, and L. sanfranciscensis JCM 5668T was independent of the others. The different biotypes of L. sanfranciscensis were present in two sourdoughs compared with other three sourdoughs. The LAB compositions of five sourdoughs were different and the relationship between intraspecies diversity of L. sanfranciscensis strains and five sourdoughs was shown by ribotyping. This study demonstrated that ribotyping was useful for distinguishing L. sanfranciscensis strains. A further important result is that the intra-species diversity of L. sanfranciscensis strains seems to be related to the sourdough preparation.

  3. Fluorene biodegradation potentials of Bacillus strains isolated from ...

    African Journals Online (AJOL)

    Fluorene biodegradation potentials of Bacillus strains isolated from tropical ... Bacillus strains, putatively identified as Bacillus subtilis BM1 and Bacillus amyloliquefaciens BR1 were ... African Journal of Biotechnology, Vol 13(14), 1554-1559 ...

  4. Isolation, identification and characterization of regional indigenous Saccharomyces cerevisiae strains

    Directory of Open Access Journals (Sweden)

    Hana Šuranská

    2016-03-01

    Full Text Available Abstract In the present work we isolated and identified various indigenous Saccharomyces cerevisiae strains and screened them for the selected oenological properties. These S. cerevisiae strains were isolated from berries and spontaneously fermented musts. The grape berries (Sauvignon blanc and Pinot noir were grown under the integrated and organic mode of farming in the South Moravia (Czech Republic wine region. Modern genotyping techniques such as PCR-fingerprinting and interdelta PCR typing were employed to differentiate among indigenous S. cerevisiae strains. This combination of the methods provides a rapid and relatively simple approach for identification of yeast of S. cerevisiae at strain level. In total, 120 isolates were identified and grouped by molecular approaches and 45 of the representative strains were tested for selected important oenological properties including ethanol, sulfur dioxide and osmotic stress tolerance, intensity of flocculation and desirable enzymatic activities. Their ability to produce and utilize acetic/malic acid was examined as well; in addition, H2S production as an undesirable property was screened. The oenological characteristics of indigenous isolates were compared to a commercially available S. cerevisiae BS6 strain, which is commonly used as the starter culture. Finally, some indigenous strains coming from organically treated grape berries were chosen for their promising oenological properties and these strains will be used as the starter culture, because application of a selected indigenous S. cerevisiae strain can enhance the regional character of the wines.

  5. Molecular characterization of lactobacilli isolated from fermented idli batter

    Directory of Open Access Journals (Sweden)

    Perumal Jayaprabha Agaliya

    2013-12-01

    Full Text Available Lactic acid bacteria are non pathogenic organism widely distributed in nature typically involved in a large number of spontaneous food fermentation. The purpose of this study was to characterize the bacteriocinogenic lactobacilli from fermented idli batter which can find application in biopreservation and biomedicine. Eight most promising lactobacilli were chosen from twenty two isolates based on their spectrum of activity against other lactic acid bacteria and pathogens. The eight lactobacilli were characterized based on the various classical phenotypic tests, physiological tests and biochemical tests including various carbohydrate utilization profiles. All isolates were homo fermentative, catalase, and gelatin negative. Molecular characterization was performed by RAPD, 16S rRNA analysis, 16S ARDRA, and Multiplex PCR for species identification. RAPD was carried out using the primer R2 and M13. Five different clusters were obtained based on RAPD indicating strain level variation. 16S rRNA analysis showed 99 to 100% homology towards Lactobacillus plantarum. The restriction digestion pattern was similar for all the isolates with the restriction enzyme AluI. The subspecies were identified by performing Multiplex PCR using species specific primer. Among the five clusters, three clusters were clearly identified as Lactobacillus plantarum subsp. plantarum, Lactobacillus pentosus, and Lactobacillus plantarum subsp. argentoratensis.

  6. Antibiotic resistance of Enterobacteriaceae strains isolated from different animals gastrointestinal tracts

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2015-05-01

    Full Text Available In this study we monitored antibiotic resistance in Enterobacteriaceae strains isolated from different animals gastrointestinal tracts  (GIT. We isolated Enterobacteriaceae from chicken, ducks, lambs, pigs, sheeps, cows and rabbits collected from slovakian farms. Enterobacteriaceae strains were cultivated on MacConkey agar at 35° ± 2°C at 24 hours. Pure cultures of Enterobacteriaceae strains were obtained by four-way streak method on Chromogenic coliform agar. Identification of purified Enterobacteriaceae strains were done by Enterotest 24 and MALDI TOF MS. For susceptibility testing disk diffusion method was used according by EUCAST. We determined the most resistance in Enterobacteriaceae strains against streptomycin, tetracycline, ampicillin, piperecillin, levofloxacine, chloramphenicol and smaller level of resistance against amikacin, ceftriaxone and ofloxacine. Equally we detected resistance to more antibiotics in one strain. The most resistance was Salmonella enterica ser. Typhimurium. Also E. coli was resistance against four antibiotics and Raoultella ornithinolytica too. Antibiotic resistance was found in other isolated strains too.

  7. Pentocin MQ1: A Novel, Broad-Spectrum, Pore-Forming Bacteriocin From Lactobacillus pentosus CS2 With Quorum Sensing Regulatory Mechanism and Biopreservative Potential

    Directory of Open Access Journals (Sweden)

    Samson B. Wayah

    2018-03-01

    Full Text Available Micrococcus luteus, Listeria monocytogenes, and Bacillus cereus are major food-borne pathogenic and spoilage bacteria. Emergence of antibiotic resistance and consumer demand for foods containing less of chemical preservatives led to a search for natural antimicrobials. A study aimed at characterizing, investigating the mechanism of action and regulation of biosynthesis and evaluating the biopreservative potential of pentocin from Lactobacillus pentosus CS2 was conducted. Pentocin MQ1 is a novel bacteriocin isolated from L. pentosus CS2 of coconut shake origin. The purification strategy involved adsorption-desorption of bacteriocin followed by RP-HPLC. It has a molecular weight of 2110.672 Da as determined by MALDI-TOF mass spectrometry and a molar extinction value of 298.82 M−1 cm−1. Pentocin MQ1 is not plasmid-borne and its biosynthesis is regulated by a quorum sensing mechanism. It has a broad spectrum of antibacterial activity, exhibited high chemical, thermal and pH stability but proved sensitive to proteolytic enzymes. It is potent against M. luteus, B. cereus, and L. monocytogenes at micromolar concentrations. It is quick-acting and exhibited a bactericidal mode of action against its targets. Target killing was mediated by pore formation. We report for the first time membrane permeabilization as a mechanism of action of the pentocin from the study against Gram-positive bacteria. Pentocin MQ1 is a cell wall-associated bacteriocin. Application of pentocin MQ1 improved the microbiological quality and extended the shelf life of fresh banana. This is the first report on the biopreservation of banana using bacteriocin. These findings place pentocin MQ1 as a potential biopreservative for further evaluation in food and medical applications.

  8. Research on the Phenotypic Characterization of Mrsa Strains Isolated from Animals

    Directory of Open Access Journals (Sweden)

    Iulia Maria BUCUR

    2017-05-01

    Full Text Available Keywords: chromogen, methicillin, MRSA, resistance Introduction: Currently, both in staphylococci isolated from animals with different diseases, as well as in humans, the MRSA strains (Methicillin Resistant S. aureus are monitored, as the methicillin resistance is associated with the resistance to other antibiotic groups. Methicillin resistance is encoded by mec staphylococcal chromosomal cassettes (SCCmec, which are islands of resistance. These strains can be identified by molecular biology tests and tests that reveal several phenotypic characteristics. The research was made in order to characterize and identify phenotypically the MRSA staphylococci strains isolated from animals. Materials and Methods: Researches were made on 240 coagulase positive and coagulase negative strains of staphylococci. Mannitol fermentation was tested on Champan medium, free coagulase was revealed on Baird-Parker medium and to identify S. aureus subsp. aureus was used the chromogenic medium Chromatic Staph. Methicillin-resistant strains were detected by disc diffusion method, using biodiscs with methicillin, oxacillin and cefoxitin. Also, to identify the MRSA strains, was used the chromogenic medium Chromatic MRSA. Results: The isolates were positive to mannitol and produced complete haemolysis or were unhaemolytic. A total of 44 strains produced free coagulase on Baird-Parker medium, considered coagulase positive strains, while 196 were coagulase negative strains. The isolates conducted differently to methicillin: 22,08% of strains were resistant, 51,25% of strains were susceptible and 26,66% had intermediate resistance, while the resistant strains to oxacillin were 42,91%. The increased frequency of methicillin-resistant strains of staphylococci and, particularly, MRSA strains, determined using the cefoxitin disk diffusion test, which is more reliable than methicillin and oxacillin. On the MRSA chromogenic medium, the methicillin-resistant strains of staphylococci

  9. Probiotic Properties of Exopolysaccharide-Producing Lactobacillus Strains Isolated from Tempoyak

    Directory of Open Access Journals (Sweden)

    Eilaf Suliman Khalil

    2018-02-01

    Full Text Available Tempoyak is a functional Malaysian food (an acid-fermented condiment which is produced from the pulp of the durian (Durio zibethinus fruit. The current study aimed to isolate and identify potential exopolysaccharide (EPS-producing Lactobacillus strains from tempoyak for potential use as probiotics. Seven isolates (DUR2, DUR4, DUR5, DUR8, DUR12, DUR18, and DUR20 out of 44 were able to produce EPS, and exhibited resistance to acid and bile salt compared to the reference strains Lactobacillus rhmnosus (ATCC53103 and L. plantarum (ATCC8014. The seven isolated strains belonged to five different species—L. plantarum, L. fermentum, L. crispatus, L. reuteri, and L. pentosus—which were identified using API 50 CHL and 16S rRNA gene sequences (Polymerase chain reaction, PCR – based. The seven strains displayed different ability to produce EPS (100–850 mg/L. Isolates exhibited a high survivability to acid (pH 3.0, bile salts (0.3%, and gastrointestinal tract model (<70%. Results showed that the auto-aggregation and cell surface hydrophobicity ranged from 39.98% to 60.09% and 50.80% to 80.53%, respectively, whereas, the highest co-aggregation value (66.44% was observed by L. fermentum (DUR8 with Pseudomonas aeruginosa. The isolates showed good inhibitory activity against tested pathogens, high antioxidant activity (32.29% to 73.36%, and good ability to reduce cholesterol (22.55% to 75.15%. Thus, the seven tested strains have value as probiotics.

  10. Proteogenomic Investigation of Strain Variation in Clinical Mycobacterium tuberculosis Isolates

    KAUST Repository

    Heunis, Tiaan

    2017-08-18

    Mycobacterium tuberculosis consists of a large number of different strains that display unique virulence characteristics. Whole-genome sequencing has revealed substantial genetic diversity among clinical M. tuberculosis isolates, and elucidating the phenotypic variation encoded by this genetic diversity will be of utmost importance to fully understand M. tuberculosis biology and pathogenicity. In this study we integrated whole-genome sequencing and mass spectrometry (GeLC-MS/MS) to reveal strain-specific characteristics in the proteomes of two clinical M. tuberculosis Latin American-Mediterranean isolates. Using this approach we identified 59 peptides containing single amino acid variants, which covered ~9% of all total coding nonsynonymous single nucleotide variants detected by whole-genome sequencing. Furthermore, we identified 29 distinct peptides that mapped to a hypothetical protein not present in the M. tuberculosis H37Rv reference proteome. Here we provide evidence for the expression of this protein in the clinical M. tuberculosis SAWC3651 isolate. The strain-specific databases enabled confirmation of genomic differences (i.e. large genomic regions of difference and nonsynonymous single nucleotide variants) in these two clinical M. tuberculosis isolates and allowed strain differentiation at the proteome level. Our results contribute to the growing field of clinical microbial proteogenomics and can improve our understanding of phenotypic variation in clinical M. tuberculosis isolates.

  11. Proteogenomic Investigation of Strain Variation in Clinical Mycobacterium tuberculosis Isolates

    KAUST Repository

    Heunis, Tiaan; Dippenaar, Anzaan; Warren, Robin M.; van Helden, Paul D.; van der Merwe, Ruben G.; Gey van Pittius, Nicolaas C.; Pain, Arnab; Sampson, Samantha L.; Tabb, David L.

    2017-01-01

    Mycobacterium tuberculosis consists of a large number of different strains that display unique virulence characteristics. Whole-genome sequencing has revealed substantial genetic diversity among clinical M. tuberculosis isolates, and elucidating the phenotypic variation encoded by this genetic diversity will be of utmost importance to fully understand M. tuberculosis biology and pathogenicity. In this study we integrated whole-genome sequencing and mass spectrometry (GeLC-MS/MS) to reveal strain-specific characteristics in the proteomes of two clinical M. tuberculosis Latin American-Mediterranean isolates. Using this approach we identified 59 peptides containing single amino acid variants, which covered ~9% of all total coding nonsynonymous single nucleotide variants detected by whole-genome sequencing. Furthermore, we identified 29 distinct peptides that mapped to a hypothetical protein not present in the M. tuberculosis H37Rv reference proteome. Here we provide evidence for the expression of this protein in the clinical M. tuberculosis SAWC3651 isolate. The strain-specific databases enabled confirmation of genomic differences (i.e. large genomic regions of difference and nonsynonymous single nucleotide variants) in these two clinical M. tuberculosis isolates and allowed strain differentiation at the proteome level. Our results contribute to the growing field of clinical microbial proteogenomics and can improve our understanding of phenotypic variation in clinical M. tuberculosis isolates.

  12. Proteogenomic Investigation of Strain Variation in Clinical Mycobacterium tuberculosis Isolates.

    Science.gov (United States)

    Heunis, Tiaan; Dippenaar, Anzaan; Warren, Robin M; van Helden, Paul D; van der Merwe, Ruben G; Gey van Pittius, Nicolaas C; Pain, Arnab; Sampson, Samantha L; Tabb, David L

    2017-10-06

    Mycobacterium tuberculosis consists of a large number of different strains that display unique virulence characteristics. Whole-genome sequencing has revealed substantial genetic diversity among clinical M. tuberculosis isolates, and elucidating the phenotypic variation encoded by this genetic diversity will be of the utmost importance to fully understand M. tuberculosis biology and pathogenicity. In this study, we integrated whole-genome sequencing and mass spectrometry (GeLC-MS/MS) to reveal strain-specific characteristics in the proteomes of two clinical M. tuberculosis Latin American-Mediterranean isolates. Using this approach, we identified 59 peptides containing single amino acid variants, which covered ∼9% of all coding nonsynonymous single nucleotide variants detected by whole-genome sequencing. Furthermore, we identified 29 distinct peptides that mapped to a hypothetical protein not present in the M. tuberculosis H37Rv reference proteome. Here, we provide evidence for the expression of this protein in the clinical M. tuberculosis SAWC3651 isolate. The strain-specific databases enabled confirmation of genomic differences (i.e., large genomic regions of difference and nonsynonymous single nucleotide variants) in these two clinical M. tuberculosis isolates and allowed strain differentiation at the proteome level. Our results contribute to the growing field of clinical microbial proteogenomics and can improve our understanding of phenotypic variation in clinical M. tuberculosis isolates.

  13. Bioactivity characterization of Lactobacillus strains isolated from dairy products

    Science.gov (United States)

    Haghshenas, Babak; Nami, Yousef; Haghshenas, Minoo; Abdullah, Norhafizah; Rosli, Rozita; Radiah, Dayang; Yari Khosroushahi, Ahmad

    2015-01-01

    This study aimed to find candidate strains of Lactobacillus isolated from sheep dairy products (yogurt and ewe colostrum) with probiotic and anticancer activity. A total of 100 samples were randomly collected from yogurt and colostrum and 125 lactic acid bacteria were isolated. Of these, 17 Lactobacillus strains belonging to five species (L. delbrueckii, L. plantarum, L. rhamnosus, L. paracasei, and L. casei) were identified. L. plantarum 17C and 13C, which isolated from colostrums, demonstrated remarkable results such as resistant to low pH and high concentrations of bile salts, susceptible to some antibiotics and good antimicrobial activity that candidate them as potential probiotics. Seven strains (1C, 5C, 12C, 13C, 17C, 7M, and 40M), the most resistant to simulated digestion, were further investigated to evaluate their capability to adhere to human intestinal Caco-2 cells. L. plantarum 17C was the most adherent strain. The bioactivity assessment of L. plantarum 17C showed anticancer effects via the induction of apoptosis on HT-29 human cancer cells and negligible side effects on one human epithelial normal cell line (FHs 74). The metabolites produced by this strain can be used as alternative pharmaceutical compounds with promising therapeutic indices because they are not cytotoxic to normal mammalian cells. PMID:26219634

  14. Identification of novel anti-inflammatory probiotic strains isolated from pulque.

    Science.gov (United States)

    Torres-Maravilla, Edgar; Lenoir, Marion; Mayorga-Reyes, Lino; Allain, Thibault; Sokol, Harry; Langella, Philippe; Sánchez-Pardo, María E; Bermúdez-Humarán, Luis G

    2016-01-01

    Probiotics are live microorganisms which when administered in adequate amounts, confer health benefits on the host. Their use is more and more widespread for both prevention and treatment of diseases, including traveler’s diarrhea and inflammatory bowel diseases (IBDs). In this work, we isolated and characterized novel candidate probiotic strains from pulque (xaxtle), a traditional Mexican alcoholic fermented beverage. A total of 14 strains were obtained from xaxtle samples isolated from three different Mexican regions. Species identification was performed by biochemical methods and 16S rRNA gene targeted PCR. The isolates belonged to the Lactobacillus plantarum, Lactobacillus paracasei, Lactobacillus brevis, and Lactobacillus composti phylogenetic groups, with L. brevis being the most dominant group. Bacteria were tested for lysozyme, low pH, and bile acid resistance. Moreover, the strains were tested for adherence to human intestinal epithelial cells and screened for their immunomodulatory properties using a cellular model. Selected bacterial strains with anti-inflammatory properties were then tested in vivo in a dinitro-benzene sulfonic acid (DNBS)-induced chronic colitis mouse model, and weight loss, gut permeability, and cytokine profiles were measured as readouts of inflammation. One of the selected strains, Lactobacillus sanfranciscensis LBH1068, improved mice health as observed by a reduction of weight loss, significant decreases in gut permeability, and cytokine modulation. Altogether, our results highlighted the potential of lactobacilli isolated from pulque and in particular the strain L. sanfranciscensis LBH1068 as a novel probiotic to treat IBD.

  15. Identification and biochemical characterization of Leishmania strains isolated in Peru, Mexico, and Spain.

    Science.gov (United States)

    Rodríguez-González, Isabel; Marín, Clotilde; Vargas, Franklin; Córdova, Ofelia; Barrera, Mario; Gutiérrez-Sánchez, Ramón; Alunda, Jose María; Sánchez-Moreno, Manuel

    2006-01-01

    Eight Leishmania promastigotes were isolated from different geographical areas: three (LP1, LP2, and LP3) from the provincial department La Libertad and the fourth (LP4) from the department of Cajamarca (northern Peru); another three (LM1, LM2, and LM3) in the province of Campeche (Mexico); and the last (LS1) from a clinical case of a dog in Madrid (Spain). The isolates were characterized by carbohydrate cell-surface residues using agglutinations with four purified lectins, by isoenzyme analysis using different isoenzymes, by analysis of kinetoplast DNA (kDNA) restriction fragment length polymorphism using four different restriction endonucleases and by the final metabolite patterns after in vitro culture. These isolates were compared with four reference strains and typified as: Leishmania (Leishmania) donovani, two strains of L. (L.) infantum, and one species of L. (Viania) peruviana. According to our results and the statistical study, the Peruvian isolates represent three different strains: one would be L. (V.) peruviana, another the strain isolated in Cajamarca (LP4) and the third would include the three strains from the department of La Libertad (LP1, LP2, and LP3), these latter three isolates being phylogenetically closer to the reference strain L. (L.) donovani. Meanwhile, the three isolates from Mexico form a group with close phylogenetic relationships to each other. The isolate from Spain belongs to the species L. (L.) infantum. Thus, a close correlation was drawn between the identity of each strain and its geographical origin.

  16. Expression of curli by Escherichia coli O157:H7 strains isolated from patients during outbreaks is different from similar strains isolated from leafy green production environments

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    Subbarao Venkata Ravva

    2016-12-01

    Full Text Available We previously reported that the strains of Escherichia coli O157:H7 (EcO157 that survived longer in austere soil environment lacked expression of curli, a fitness trait linked with intestinal colonization. In addition, the proportion of curli-positive variants of EcO157 decreased with repeated soil exposure. Here we evaluated 84 and 176 clinical strains from outbreaks and sporadic infections in the US, plus 211 animal fecal and environmental strains for curli expression. These shiga-toxigenic strains were from 328 different genotypes, as characterized by multi-locus variable-number tandem-repeat analysis (MLVA. More than half of the fecal strains (human and animal and a significant proportion of environmental isolates (82% were found to lack curli expression. EcO157 strains from several outbreaks linked with the consumption of contaminated apple juice, produce, hamburgers, steak and beef were also found to lack curli expression. Phylogenetic analysis of fecal strains indicates curli expression is distributed throughout the population. However, a significant proportion of animal fecal isolates (84% gave no curli expression compared to human fecal isolates (58%. In addition, analysis of environmental isolates indicated nearly exclusive clustering of curli expression to a single branch of the minimal spanning tree. This indicates that curli expression depends primarily upon the type of environmental exposure and the isolation source, although genotypic differences also contribute to clonal variation in curli. Furthermore, curli-deficient phenotype appears to be a selective trait for survival of EcO157 in agricultural environments.

  17. Postmating Reproductive isolation between strains of Drosophila willistoni.

    Science.gov (United States)

    Mardiros, Xian B; Park, Ronni; Clifton, Bryan; Grewal, Gurman; Khizar, Amina K; Markow, Therese A; Ranz, José M; Civetta, Alberto

    2016-10-01

    Speciation can occur through the presence of reproductive isolation barriers that impede mating, restrict cross-fertilization, or render inviable/sterile hybrid progeny. The D. willistoni subgroup is ideally suited for studies of speciation, with examples of both allopatry and sympatry, a range of isolation barriers, and the availability of one species complete genome sequence to facilitate genetic studies of divergence. D. w. willistoni has the largest geographic distribution among members of the Drosophila willistoni subgroup, spanning from Argentina to the southern United States, including the Caribbean islands. A subspecies of D. w. willistoni, D. w. quechua, is geographically separated by the Andes mountain range and has evolved unidirectional sterility, in that only male offspring of D. w. quechua females × D. w. willistoni males are sterile. Whether D. w. willistoni flies residing east of the Andes belong to one or more D. willistoni subspecies remains unresolved. Here we perform fecundity assays and show that F1 hybrid males produced from crosses between different strains found in Central America, North America, and northern Caribbean islands are reproductively isolated from South American and southern Caribbean island strains as a result of unidirectional hybrid male sterility. Our results show the existence of a reproductive isolation barrier between the northern and southern strains and suggest a subdivision of the previously identified D. willistoni willistoni species into 2 new subspecies.

  18. Genetic relatedness of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated in south Asia.

    Science.gov (United States)

    Talukder, Kaisar A; Khajanchi, Bijay K; Islam, M Aminul; Dutta, Dilip K; Islam, Zhahirul; Safa, Ashrafus; Khan, G Y; Alam, Khorshed; Hossain, M A; Malla, Sarala; Niyogi, S K; Rahman, Mustafizur; Watanabe, Haruo; Nair, G Balakrish; Sack, David A

    2004-10-01

    The aim of the present study was to determine the clonal relationships of ciprofloxacin-resistant Shigella dysenteriae type 1 strains isolated from south Asia, and S. dysenteriae 1 strains associated with epidemics in 1978, 1984 and 1994. The antimicrobial susceptibilities were examined by NCCLS methods. Molecular epidemiological characterization was performed by plasmid profiling, pulsed-field gel electrophoresis (PFGE) and mutation analysis of the quinolone resistance-determining region (QRDR) of gyrA by sequencing. Plasmid patterns of the current ciprofloxacin-resistant strains from India, Nepal and Bangladesh were very similar to those of the 1978, 1984 and 1994 epidemic isolates of S. dysenteriae 1, except for the presence of a new plasmid of approximately 2.6 MDa, which was found in one recent ciprofloxacin-resistant strain isolated in Bangladesh. PFGE analysis showed that the ciprofloxacin-resistant strains isolated in Bangladesh, India and Nepal belonged to a PFGE type (type A), which was possibly related to that of the 1984 and 1994 clone of S. dysenteriae 1, but different from 1978 epidemic strains. The current ciprofloxacin-resistant strains belong to five subtypes (A3-A7), all of which were found in India, but in Bangladesh and Nepal, only A3 existed. Mutation analysis of the QRDR of gyrA revealed that amino acid substitutions at positions 83 and 87 of ciprofloxacin-resistant strains isolated in Bangladesh were similar to those of the strains isolated in Nepal, but different (at position 87) from ciprofloxacin-resistant strains isolated in India. PFGE and mutation analysis of gyrA showed differences between the current ciprofloxacin-resistant S. dysenteriae 1 strains isolated in south Asia and those associated with epidemics in 1978, 1984 and 1994.

  19. Safety Evaluation of Enterocin Producer Enterococcus sp. Strains Isolated from Traditional Turkish Cheeses.

    Science.gov (United States)

    Avcı, Mine; Özden Tuncer, Banu

    2017-07-06

    The purpose of this study was to determine the antimicrobial activity and occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate some of their virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. Structural genes entA, entB, entP and entX were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated anyβ-haemolytic activity and only one strain had gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was detected only in this strain.

  20. Isolation and characterization of lipase-producing Bacillus strains ...

    African Journals Online (AJOL)

    Bacillus strains (B1 - B5) producing extra cellular lipase were isolated from the soil sample of coconut oil industry. The strains were identified by morphological and biochemical characters. Growth of the organisms and lipase production were measured with varying pH (4 - 9) temperature (27, 37 and 47ºC) and various ...

  1. Phylogenetic analysis of rabbit haemorrhagic disease virus (RHDV) strains isolated in Poland.

    Science.gov (United States)

    Fitzner, Andrzej; Niedbalski, Wieslaw

    2017-10-01

    The aim of this study was to characterise the nucleotide and amino acid sequence of complete genomes (7.5 kb) from RHDV strains isolated in Poland and estimate the genetic variability in different elements of the viral RNA. In addition, the sequence of Polish RHDV isolates isolated from 1988-2015 was compared with the sequences of other European RHDV, including the RHDVa and RHDV2/RHDVb subtypes. The complete sequence was developed by the compilation of partial nucleotide sequences. This sequence consisted of approximately 7428 nucleotides. For comparison of nucleotide sequences and the development of phylogenetic trees of Polish RHDV isolates and reference RHDV strains representing the main phylogenetic groups of classical RHDV, RHDVa and RHDV2 as well as the non-pathogenic rabbit lagovirus RCV, the BLAST software with blastn and MEGA6 with neighbour-joining method was applied. The complete nucleotide sequence of Polish isolates of RHDV has also been entered into GenBank. For comparative analysis, nineteen complete sequences representing the main RHDV genetic types available in GenBank were used. The results of phylogenetic analysis of Polish RHDV strains reveals the presence of three classical RHDV genogroups (G2, G4 and G5) and an RHDVa variant (G6). The oldest RHDV isolates (KGM 1988, PD 1989 and MAL 1994) belong to genogroup G2. It can be assumed that the elimination of these strains from the environment probably occurred at the turn of 1994 and 1995. Genogroup G2 was replaced by the phylogenetically younger BLA 1994 and OPO 2004 strains from genogroup G4, which probably originated from the G3 lineage, represented by the Italian strains BS89. The last representatives of classical RHDV in Poland are isolates GSK 1988 and ZD0 2000 from genogroup G5. A single clade contains the Polish RHDV strains from 2004-2015 (GRZ 2004, KRY 2004, L145 2004, W147 2005, SKO 2013, GLE 2013, RED1 2013, STR 2012, STR2 2013, STR 2014, BIE 2015) identified as RHDVa, which clustered

  2. [Production of pertussis toxin by Bordetella pertussis strains isolated from patients with whooping cough].

    Science.gov (United States)

    Zaĭtsev, E M; Mertsalova, N U; Shinkarev, A S; Mazurova, I K; Zakharova, N S

    2011-01-01

    To assess level of pertussin toxin (PT) production by vaccine strains of Bordetella pertussis and strains isolated from patients with whooping cough. Concentration of PT in supernatants of microbial cultures of 3 vaccine strains and 25 strains of B. pertussis isolated from patients with pertussis in 2001 - 2005 was measured with enzyme immunoassay using gamma-globulin fractions of rabbit antiserum to PT as immunosorbent or included in peroxidase conjugates. Level of PT production by strains isolated from infected persons varied from 3 +/- 0.5 to 64.8 +/- 12.2 ng/MFU/ml: in 9 strains--from 3 +/- 0.5 to 9.4 +/- 2.1 ng/MFU/ml, in 7--10.5 +/- 1.8 to 18.4 +/- 2.6 ng/MFU/ml, and in 9--23.6 +/- 4.5 to 64.8 +/- 12.2 ng/MFU/ml. B. pertussis strains isolated from patients were heterogeneous on level of PT production. Difference in expression of PT between strains were as high as 20-fold. Conditionally low, moderate and high levels of PT production had 9 (36%), 7 (28%), and 9 (36%) of 25 studied strains. Three vaccine strains had levels of toxin production similar to recently isolated strains with moderate level of its production.

  3. Lactobacillus herbarum sp. nov., a species related to Lactobacillus plantarum.

    Science.gov (United States)

    Mao, Yuejian; Chen, Meng; Horvath, Philippe

    2015-12-01

    Strain TCF032-E4 was isolated from a traditional Chinese fermented radish. It shares >99% 16S rRNA sequence identity with L. plantarum, L. pentosus and L. paraplantarum. This strain can ferment ribose, galactose, glucose, fructose, mannose, mannitol, N-acetylglucosamine, amygdalin, arbutin, salicin, cellobiose, maltose, lactose, melibiose, trehalose and gentiobiose. It cannot ferment sucrose, which can be used by L. pentosus, L. paraplantarum, L. fabifermentans, L. xiangfangensis and L. mudanjiangensis, as well as most of the L. plantarum strains (88.7%). TCF032-E4 cannot grow at temperature above 32 °C. This strain shares 78.2-83.6% pheS (phenylalanyl-tRNA synthetase alpha subunit) and 89.5-94.9% rpoA (RNA polymerase alpha subunit) sequence identity with L. plantarum, L. pentosus, L. paraplantarum, L. fabifermentans, L. xiangfangensis and L. mudanjiangensis. These results indicate that TCF032-E4 represents a distinct species. This hypothesis was further confirmed by whole-genome sequencing and comparison with available genomes of related species. The draft genome size of TCF032-E4 is approximately 2.9 Mb, with a DNA G+C content of 43.5 mol%. The average nucleotide identity (ANI) between TCF032-E4 and related species ranges from 79.0 to 81.1%, the highest ANI value being observed with L. plantarum subsp. plantarum ATCC 14917T. A novel species, Lactobacillus herbarum sp. nov., is proposed with TCF032-E4T ( = CCTCC AB2015090T = DSM 100358T) as the type strain.

  4. Isolation and characterization of new strains of methanogens from cold terrestrial habitats.

    Science.gov (United States)

    Simankova, Maria V; Kotsyurbenko, Oleg R; Lueders, Tillmann; Nozhevnikova, Alla N; Wagner, Bianca; Conrad, Ralf; Friedrich, Michael W

    2003-06-01

    Five strains of methanogenic archaea (MT, MS, MM, MSP, ZB) were isolated from permanently and periodically cold terrestrial habitats. Physiological and morphological studies, as well as phylogenetic analyses of the new isolates were performed. Based on sequences of the 16S rRNA and methyl-coenzyme M reductase a-subunit (mcrA) genes all new isolates are closely related to known mesophilic and psychrotolerant methanogens. Both, phylogenetic analyses and phenotypic properties allow to classify strains MT, MS, and MM as members of the genus Methanosarcina. Strain MT is a new ecotype of Methanosarcina mazei, whereas strains MM and MS are very similar to each other and can be assigned to the recently described psychrotolerant species Methanosarcina lacustris. The hydrogenotrophic strain MSP is a new ecotype of the genus Methanocorpusculum. The obligately methylotrophic strain ZB is closely related to Methanomethylovorans hollandica and can be classified as new ecotype of this species. All new isolates, including the strains from permanently cold environments, are not true psychrophiles according to their growth temperature characteristics. In spite of the ability of all isolates to grow at temperatures as low as 1-5 degrees C, all of them have their growth optima in the range of moderate temperatures (25-35 degrees C). Thus, they can be regarded as psychrotolerant organisms. Psychrotolerant methanogens are thought to play an important role in methane production in both, habitats under seasonal temperature variations or from permanently cold areas.

  5. Different distribution patterns of ten virulence genes in Legionella reference strains and strains isolated from environmental water and patients.

    Science.gov (United States)

    Zhan, Xiao-Yong; Hu, Chao-Hui; Zhu, Qing-Yi

    2016-04-01

    Virulence genes are distinct regions of DNA which are present in the genome of pathogenic bacteria and absent in nonpathogenic strains of the same or related species. Virulence genes are frequently associated with bacterial pathogenicity in genus Legionella. In the present study, an assay was performed to detect ten virulence genes, including iraA, iraB, lvrA, lvrB, lvhD, cpxR, cpxA, dotA, icmC and icmD in different pathogenicity islands of 47 Legionella reference strains, 235 environmental strains isolated from water, and 4 clinical strains isolated from the lung tissue of pneumonia patients. The distribution frequencies of these genes in reference or/and environmental L. pneumophila strains were much higher than those in reference non-L. pneumophila or/and environmental non-L. pneumophila strains, respectively. L. pneumophila clinical strains also maintained higher frequencies of these genes compared to four other types of Legionella strains. Distribution frequencies of these genes in reference L. pneumophila strains were similar to those in environmental L. pneumophila strains. In contrast, environmental non-L. pneumophila maintained higher frequencies of these genes compared to those found in reference non-L. pneumophila strains. This study illustrates the association of virulence genes with Legionella pathogenicity and reveals the possible virulence evolution of non-L. pneumophia strains isolated from environmental water.

  6. Plasmids in Vibrio parahemolyticus strains isolated in Japan and Bangladesh with special reference to different distributions.

    Science.gov (United States)

    Arai, T; Ando, T; Kusakabe, A; Ullah, M A

    1983-01-01

    We surveyed plasmids in naturally occurring Vibrio parahemolyticus strains isolated in Japan and Bangladesh. Among the strains isolated in Japan, about half of the strains isolated from stools of patients of domestic diarrhea outbreaks as well as of travelers returning from East Asia were found to have plasmids, but no strains from foods had plasmids. In contrast, among the strains isolated in Bangladesh, none of the four strains isolated from patients had plasmids, but two out of eight strains isolated from water had plasmids, suggesting that plasmids are common in strains from the water in Bangladesh. All plasmids so far reported in V. parahemolyticus were detected in strains isolated from stools of patients. Incidences of plasmids in this organism were not so high in either area. In Japan, all plasmids were detected in strains from human intestines at 37 C, but in Bangladesh, where the temperature is around 30-40 C, the plasmids were detected in strains from the natural environment. These results suggested the possibility that these plasmids can come from different bacteria under rather high temperatures and that incidences of plasmids are influenced by the incidences of plasmids in bacteria present in the vicinity of V. parahemolyticus strains. None of these plasmids were found to have any relation to the biological characters tested.

  7. Isolation and Antibiotic Sensitivity of Bacillus thuringinesis Strain From Dump Soil

    Directory of Open Access Journals (Sweden)

    Sarker, D.

    2010-01-01

    Full Text Available Bacillus thuringiensis (or Bt is a commonly used as a pesticide. B. thuringiensis is a naturally-occurring soil bacterium, also occurs naturally in the gut of caterpillars of various types of moths and butterflies, as well as on the dark surface of plants. The xylanase producing bacterial strains were isolated from dump soil. The strains were isolated on xylan agar media and screening was carried out by xylanolysis method. To test the sensitivity of the isolates, ten different antibiotics were used. The strains were tested for resistance to doxycyclin, erythromycin, chloramphenical, cephallaxin, kanamycin, ampicillin, steptomycin, vancomycin, amoxycillin and neomycin. The strains showed sensitive to doxycyclin, erythromycin, chloramphenical, cephallaxin, kanamycin, ampicillin, steptomycin and vancomycin and also showed resistance to amoxycillin and neomycin, when tested by disc diffusion method on nutrient agar plate confirmed by antibiotic spread plate method. The inhibitory effect of B. thuringiensis strains against the test bacteria Bacillus subtilis, Sarcina lutca, Shigella dysenteriae, Shigella sonnei and Pseudomonus aeruginosa examined. It was found that, B. thuringiensis S1, B. thuringiensis S2 and B. thuringiensis S3 strains showed an inhibitory effect on all of the test bacteria.

  8. Primary Isolation Strain Determines Both Phage Type and Receptors Recognised by Campylobacter jejuni Bacteriophages

    DEFF Research Database (Denmark)

    Sørensen, Martine C. Holst; Gencay, Yilmaz Emre; Birk, Tina

    2015-01-01

    were identified based on host range analysis and genome restriction profiles. Most phages were isolated using C. jejuni strains NCTC12662 and RM1221 and interestingly phage genome size (140 kb vs. 190 kb), host range and morphological appearance correlated with the isolation strain. Thus, according......In this study we isolated novel bacteriophages, infecting the zoonotic bacterium Campylobacter jejuni. These phages may be used in phage therapy of C. jejuni colonized poultry to prevent spreading of the bacteria to meat products causing disease in humans. Many C. jejuni phages have been isolated...... therefore chose seven C. jejuni strains each expressing different CPS structures as indicator strains in a large screening for phages in samples collected from free-range poultry farms. Forty-three phages were isolated using C. jejuni NCTC12658, NCTC12662 and RM1221 as host strains and 20 distinct phages...

  9. Molecular characterization of Streptococcus agalactiae strains isolated from fishes in Malaysia.

    Science.gov (United States)

    Amal, M N A; Zamri-Saad, M; Siti-Zahrah, A; Zulkafli, A R; Nur-Nazifah, M

    2013-07-01

    The aim of this study was to characterize Streptococcus agalactiae strains that were isolated from fishes in Malaysia using random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic PCR (REP-PCR) techniques. A total of 181 strains of Strep. agalactiae isolated from red hybrid tilapia (Oreochromis sp.) and golden pompano (Trachinotus blochii) were characterized using RAPD and REP-PCR techniques. Both the fingerprinting techniques generated reproducible band patterns, differing in the number and molecular mass amplicons. The RAPD technique displayed greater discriminatory power by its production of more complex binding pattern and divided all the strains into 13 groups, compared to 9 by REP-PCR technique. Both techniques showed the availability to differentiate the genetic profiles of the strains according to their geographical location of origin. Three strains of Strep. agalactiae that were recovered from golden pompano showed a genetic dissimilarity from the strains isolated from red hybrid tilapia, while the strain of ATCC 27956 that recovered from bovine displayed a unique profile for both methods. Both techniques possess excellent discriminative capabilities and can be used as a rapid means of comparing Strep. agalactiae strains for future epidemiological investigation. Framework as the guideline in traceability of this disease and in the search for potential local vaccine candidates for streptococcosis in this country. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

  10. Characterization of Probiotic Abilities of Lactobacilli Isolated from Iranian Koozeh Traditional Cheese

    Directory of Open Access Journals (Sweden)

    Tavakoli Mahmoud

    2017-03-01

    Full Text Available Eight lactic isolates including Lactobacillus plantarum (MT.ZH193, MT.ZH293, MT.ZH393 and MT.ZH593, L. casei (MT.ZH493, L. pentosus (MT.ZH693, and L. fermentum (MT.ZH893 and MT.ZH993 were identified from an Iranian traditional cheese “Koozeh Paneer” using the morphological, phenotypical, biochemical and molecular characterization and then their probiotic characteristics were compared. Results showed that the lactic isolates of L. plantarum (MT.ZH293 and L. fermentum (MT.ZH893 and MT.ZH993 were resistant to all the used bile salts up to concentrations of 0.3 to 2.0%. All the strains showed low sensitivity to the presence of conjugated bile salts. L. plantarum MT.ZH293 exhibited the highest enzymatic activity of β-galactosidase and survival rate in a simulated stomach duodenum passage. L. casei MT.ZH493 generated the highest amount of hydrogen peroxide, followed by L. fermentum MT.ZH993 and L. plantarum MT.ZH593. Although the most selected LAB isolates had a moderate cell surface hydrophobicity, L. plantarum MT. ZH593 expressed the highest cell surface hydrophobicity. L. fermentum MT.ZH893 had strong resistance to all the antibiotics tested such as amoxicillin, ceftriaxon, chloramphenicol, erythromycin, gentamycin, streptomycin, tetracycline and vancomycin. Five lactic strains of L. plantarum (MT.ZH193, MT.ZH393 and MT.ZH593 and L. fermentum (MT.ZH893 and MT.ZH993 inhibited the growth of the tested foodborne pathogens including Escherichia coli PTCC5052, Salmonella enterica, Enetrococcus hirea, Staphylococcus aureus and Pseudomonas aeruginosa.

  11. Antimicrobial resistance of bacterial strains isolated from avian cellulitis

    Directory of Open Access Journals (Sweden)

    MM Santos

    2014-03-01

    Full Text Available Avian cellulitis is an inflammatory process in the subcutaneous tissue, mainly located in the abdomen and thighs. This problem is commonly observed in poultry at slaughter and it is considered one of the major causes of condemnation of carcasses in Brazil. The aim of this study was to perform the microbial isolation of lesions of avian cellulitis from a processing plant located in the State of Goiás in order to analyze antimicrobial resistance by antibiogram test and to detect resistance genes by polymerase chain reaction. A total of 25 samples of avian cellulitis lesions were analyzed, from which 30 bacterial strains were isolated. There were eleven (44% strains of Escherichia coli, nine (36% strains of Staphylococcus epidermidis, seven (28% strains of Proteus mirabilis and three (12% strains of Manheimiahaemolytica. The antibiogram test showed that all strains were resistant to at least one antimicrobial. The gene of antimicrobial resistance tetB was detected in E. coli, S. epidermidis and P. mirabilis strains, and was the most frequently observed gene. The gene of antimicrobial resistance Sul1 was detected in all bacterial species, while tetA was found in E. coli and S. epidermidis strains, SHV in E. coli strains, S. epidermidis and P. mirabilis,and cat1 in one P. mirabilis strain. The results suggest a potential public health hazard due to the ability of these microorganisms to transmit antimicrobial resistancegenes to other microorganisms present in the intestinal tract of humans and animals, which may affect clinical-medical usage of these drugs.

  12. In Vitro and in Vivo Selection of Potentially Probiotic Lactobacilli From Nocellara del Belice Table Olives

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    Barbara Guantario

    2018-03-01

    Full Text Available Table olives are increasingly recognized as a vehicle as well as a source of probiotic bacteria, especially those fermented with traditional procedures based on the activity of indigenous microbial consortia, originating from local environments. In the present study, we report characterization at the species level of 49 Lactic Acid Bacteria (LAB strains deriving from Nocellara del Belice table olives fermented with the Spanish or Castelvetrano methods, recently isolated in our previous work. Ribosomal 16S DNA analysis allowed identification of 4 Enterococcus gallinarum, 3 E. casseliflavus, 14 Leuconostoc mesenteroides, 19 Lactobacillus pentosus, 7 L. coryniformis, and 2 L. oligofermentans. The L. pentosus and L. coryniformis strains were subjected to further screening to evaluate their probiotic potential, using a combination of in vitro and in vivo approaches. The majority of them showed high survival rates under in vitro simulated gastro-intestinal conditions, and positive antimicrobial activity against Salmonella enterica serovar Typhimurium, Listeria monocytogenes and enterotoxigenic Escherichia coli (ETEC pathogens. Evaluation of antibiotic resistance to ampicillin, tetracycline, chloramphenicol, or erythromycin was also performed for all selected strains. Three L. coryniformis strains were selected as very good performers in the initial in vitro testing screens, they were antibiotic susceptible, as well as capable of inhibiting pathogen growth in vitro. Parallel screening employing the simplified model organism Caenorhabditis elegans, fed the Lactobacillus strains as a food source, revealed that one L. pentosus and one L. coryniformis strains significantly induced prolongevity effects and protection from pathogen-mediated infection. Moreover, both strains displayed adhesion to human intestinal epithelial Caco-2 cells and were able to outcompete foodborne pathogens for cell adhesion. Overall, these results are suggestive of beneficial

  13. MICROBIOLOGICAL CHARACTERISATION OF Haemophilus influenzae STRAINS ISOLATED FROM PATIENTS WITH INVASIVE AND RESPIRATORY DISEASES

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    Tomislav Kostyanev

    2010-01-01

    Full Text Available A total of 175 H. influenzae strains were collected between 1994 and 2009 from all aged patient groups. The strains were isolated from patients with invasive and community-acquired respiratory tract infections. All strains were identified according to standard microbiological methods. Serotyping was done by a coagglutination test and by molecular PCR capsular genotyping. Beta-lactamase production was determined by the chromogenic cephalosporin test with nitrocephin as substrate. Most of the isolated H. influenzae strains were from children under 5 years of age (57.7%. Overall, 61 strains belonged to serotype b (34.9% by the means of PCR capsular typing, 1 strain was type f, and 113 isolates (64.6% were non-typeable (non-encapsulated H. influenzae. Among the infants and children with meningitis or other invasive infections, aged 2 month to 5 years, all strains, except one, were serotype b. In respiratory tract infections (pneumonia, otitis media, sinusitis and people with chronic pulmonary diseases - exacerbations of COPD, bronchiectasis, cystic fibrosis the most common - 96.5% were non-typeable strains in both groups children and adults. Overall, the prevalence of beta-lactamase production was 19.4%. But, it was much higher for invasive strains from CSF isolates - 37.7%, 25% in blood samples, and 37.5% in otitis media causative strains. Beta-lactamase production was less frequent in respiratory tract isolates - in sputum 13.3% and in URT samples - 2.3%. The rate of beta-lactamase production in CSF isolates has not changed for the last 10 years.PCR capsular genotyping method has to be performed for all non-b-type strains. The implementation of Hib vaccine in our country will be accompanied by a reduction in invasive diseases caused by H. influenzae type b in children, but it is not useful in preventing infections caused by non-typeable H. influenzae strains.

  14. Isolation of Dickeya dadantii strains from potato disease and biocontrol by their bacteriophages

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    Abbas Soleimani-Delfan

    2015-09-01

    Full Text Available One of the most economically important bacterial pathogens of plants and plant products is Dickeya dadantii. This bacterium causes soft rot disease in tubers and other parts of the potato and other plants of the Solanaceae family. The application of restricted host range bacteriophages as biocontrol agents has recently gained widespread interest. This study purposed to isolate the infectious agent of the potato and evaluate its biocontrol by bacteriophages. Two phytopathogenic strains were isolated from infected potatoes, identified based on biochemical and 16S rRNA gene sequencing, and submitted to GenBank as D. dadantii strain pis3 (accession no. HQ423668 and D. dadantii strain sip4 (accession no. HQ423669. Their bacteriophages were isolated from Caspian Sea water by enriching the water filtrate with D. dadantii strains as hosts using spot or overlay methods. On the basis of morphotypes, the isolated bacteriophages were identified as members of the Myoviridae and Siphoviridae families and could inhibit the growth of antibiotic resistant D. dadantii strains in culture medium. Moreover, in Dickeya infected plants treated with bacteriophage, no disease progression was detected. No significant difference was seen between phage-treated and control plants. Thus, isolated bacteriophages can be suggested for the biocontrol of plant disease caused by Dickeya strains.

  15. Isolation and Preliminary Screening of a Weissella confusa Strain from Giant Panda (Ailuropoda melanoleuca).

    Science.gov (United States)

    Xiong, Lvchen; Ni, Xueqin; Niu, Lili; Zhou, Yi; Wang, Qiang; Khalique, Abdul; Liu, Qian; Zeng, Yan; Shu, Gang; Pan, Kangcheng; Jing, Bo; Zeng, Dong

    2018-04-13

    Weissella confusa has recently received attention for its probiotic potential. Some W. confusa and Weissella cibaria strains isolated from fermented foods show favorable probiotic effects. However, the probiotic properties of W. confusa isolated from giant panda remain unreported to date. Thus, this study isolated a W. confusa strain from giant panda feces and then investigated its characteristics and probiotic properties. A lactic acid bacteria strain was isolated from giant panda fecal samples. The isolated strain was screened by in vitro probiotic property tests, including in vitro antimicrobial test, antioxidant test, surface hydrophobicity, and stress resistance. On the basis of biochemical identification and 16S rDNA sequencing, the W. confusa strain was identified as BSP201703. This Weissella confusa strain can survive at pH 2 and 0.3% (w/v) concentration of bile salt environment and inhibit common intestinal pathogens. It also possesses an in vitro antioxidant capacity, a high auto-aggregation ability, and a high surface hydrophobicity. BSP201703 might serve as a probiotic to giant pandas.

  16. Acetobacter strains isolated during the acetification of blueberry (Vaccinium corymbosum L.) wine.

    Science.gov (United States)

    Hidalgo, C; García, D; Romero, J; Mas, A; Torija, M J; Mateo, E

    2013-09-01

    Highbush blueberries (Vaccinium corymbosum L.) are known to have positive health benefits. The production of blueberry vinegar is one method to preserve this seasonal fruit and allow extended consumption. In this study, blueberry wine acetification was performed with naturally occurring micro-organisms and with an inoculated Acetobacter cerevisiae strain. Acetifications were carried out in triplicate using the Schützenbach method. The successful spontaneous processes took up to 66% more time than the processes involving inoculation. The isolation of acetic acid bacteria (AAB) and the analysis of these AAB using molecular methods allowed the identification of the main genotypes responsible of the blueberry acetification. Although the Acet. cerevisiae strain was the predominant strain isolated from the inoculated process samples, Acetobacter pasteurianus was isolated from samples for both processes and was the only species present in the spontaneous acetification samples. To the best of our knowledge, this is the first report describing the identification and variability of AAB isolated during blueberry acetification. The isolated Acet. pasteurianus strains could be used for large-scale blueberry vinegar production or as a starter culture in studies of other vinegar production methods. © 2013 The Society for Applied Microbiology.

  17. Antibiotic resistance determinants in a Pseudomonas putida strain isolated from a hospital.

    Directory of Open Access Journals (Sweden)

    Lázaro Molina

    Full Text Available Environmental microbes harbor an enormous pool of antibiotic and biocide resistance genes that can impact the resistance profiles of animal and human pathogens via horizontal gene transfer. Pseudomonas putida strains are ubiquitous in soil and water but have been seldom isolated from humans. We have established a collection of P. putida strains isolated from in-patients in different hospitals in France. One of the isolated strains (HB3267 kills insects and is resistant to the majority of the antibiotics used in laboratories and hospitals, including aminoglycosides, ß-lactams, cationic peptides, chromoprotein enediyne antibiotics, dihydrofolate reductase inhibitors, fluoroquinolones and quinolones, glycopeptide antibiotics, macrolides, polyketides and sulfonamides. Similar to other P. putida clinical isolates the strain was sensitive to amikacin. To shed light on the broad pattern of antibiotic resistance, which is rarely found in clinical isolates of this species, the genome of this strain was sequenced and analysed. The study revealed that the determinants of multiple resistance are both chromosomally-borne as well as located on the pPC9 plasmid. Further analysis indicated that pPC9 has recruited antibiotic and biocide resistance genes from environmental microorganisms as well as from opportunistic and true human pathogens. The pPC9 plasmid is not self-transmissible, but can be mobilized by other bacterial plasmids making it capable of spreading antibiotic resistant determinants to new hosts.

  18. Characterization and Strains of Mycobacteria Isolated from Cattle ...

    African Journals Online (AJOL)

    Characterization and Strains of Mycobacteria Isolated from Cattle Carcasses in Refrigerated Slaughterhouse Bamako Goal. Y S Kone, A Cisse, S S Sidibe, Z Tarnagda, S Diarra, D Yassa, P Coulibaly, B Traore ...

  19. Isolation, Identification, and Evaluation of Novel Probiotic Strains Isolated from Feces of Breast-Fed Infants.

    Science.gov (United States)

    Panya, Marutpong; Lulitanond, Viraphong; Rattanachaikunsopon, Pongsak; Srivoramas, Thanyakarn; Chaiwong, Tarinee

    2016-01-01

    To isolate, identify, and evaluate the probiotic properties of lactic acid bacteria (LAB) isolated from the feces of breast-fed infants. The probiotic tests included investigation of hemolysis activity, survival in simulated gastrointestinal tract conditions (acid and bile salt tolerance), susceptibility to antibiotics, and ability to inhibit selected bacterial pathogens (Escherichia coli O157:H7, Vibrio cholerae and Salmonella enterica subsp enterica serovar Typhimurium). The bacterial species identification was performed by both carbohydrate utilization and partial 16S ribosomal RNA sequencing. Five of fifty LAB isolates (UBU-03, UBU-06, UBU-09, UBU-34, and UBU-37) showed good probiotic properties. These five isolates showed non-hemolysis type (gamma-hemolysis), susceptibility to all antibiotics tested except for vancomycin, ability to survive in the simulated gastrointestinal conditions of both acid and bile salt solution, and ability to inhibit growth of E. coli O157: H7 and V. cholerae. Bacterial species identification revealed that all five isolates were firmly identified as Lactobacillus rhamnosus species. The L. rhamnosus strains that were isolated and characterized in this study could be considered as probiotic strains, and then used for further probiotic characterization in human cell cultures or animal models.

  20. Diversity of Geotrichum candidum strains isolated from traditional cheesemaking fabrications in France.

    Science.gov (United States)

    Marcellino, N; Beuvier, E; Grappin, R; Guéguen, M; Benson, D R

    2001-10-01

    The diversity of French fungus-ripened cheeses is due partly to the succession of fungi that colonize the cheese during ripening. Geotrichum candidum appears in the early stages of ripening on soft cheeses such as Camembert and semihard cheeses such as St. Nectaire and Reblochon. Its lipases and proteases promote flavor development, and its aminopeptidases reduce bitterness imparted by low-molecular-weight peptides in cheese. We assessed the genetic diversity of G. candidum strains by using random amplification of polymorphic DNA (RAPD)-PCR correlated with phenotypic tests for carbon assimilation and salt tolerance. Strains were isolated from milk, curd, and cheese collected in seven major cheesemaking regions of France. Sixty-four isolates were characterized. We found high genetic diversity of G. candidum even within the same cheesemaking regions. Strains did not group according to region. All of the strains from the Haute-Savoie were able to assimilate lactate as the sole source of carbon, while lactate assimilation varied among strains from the Auvergne. Strains varied in D-mannitol assimilation, and none used citrate as the sole source of carbon. Yeast-like colony morphology predominated in Reblochon, while all of the strains isolated from St. Nectaire were filamentous. The RAPD-PCR technique readily differentiated Geotrichum fragrans isolated from milk and curd in a St. Nectaire cheesemaking facility. This study reveals an enormous diversity of G. candidum that has been empirically selected through the centuries by the cheesemakers of France.

  1. Primary isolation strain determines both phage type and receptors recognised by Campylobacter jejuni bacteriophages.

    Directory of Open Access Journals (Sweden)

    Martine C Holst Sørensen

    Full Text Available In this study we isolated novel bacteriophages, infecting the zoonotic bacterium Campylobacter jejuni. These phages may be used in phage therapy of C. jejuni colonized poultry to prevent spreading of the bacteria to meat products causing disease in humans. Many C. jejuni phages have been isolated using NCTC12662 as the indicator strain, which may have biased the selection of phages. A large group of C. jejuni phages rely on the highly diverse capsular polysaccharide (CPS for infection and recent work identified the O-methyl phosphoramidate modification (MeOPN of CPS as a phage receptor. We therefore chose seven C. jejuni strains each expressing different CPS structures as indicator strains in a large screening for phages in samples collected from free-range poultry farms. Forty-three phages were isolated using C. jejuni NCTC12658, NCTC12662 and RM1221 as host strains and 20 distinct phages were identified based on host range analysis and genome restriction profiles. Most phages were isolated using C. jejuni strains NCTC12662 and RM1221 and interestingly phage genome size (140 kb vs. 190 kb, host range and morphological appearance correlated with the isolation strain. Thus, according to C. jejuni phage grouping, NCTC12662 and NCTC12658 selected for CP81-type phages, while RM1221 selected for CP220-type phages. Furthermore, using acapsular ∆kpsM mutants we demonstrated that phages isolated on NCTC12658 and NCTC12662 were dependent on the capsule for infection. In contrast, CP220-type phages isolated on RM1221 were unable to infect non-motile ∆motA mutants, hence requiring motility for successful infection. Hence, the primary phage isolation strain determines both phage type (CP81 or CP220 as well as receptors (CPS or flagella recognised by the isolated phages.

  2. Antimicrobial drug susceptibility of Neisseria meningitidis strains isolated from carriers

    Directory of Open Access Journals (Sweden)

    Dayamí García

    2000-06-01

    Full Text Available When it is necessary to determine the susceptibility of Neisseria meningitidis (Nm strains to antimicrobial drugs, it is important to consider that it should be analyzed in a double context. One of them related to the use of drugs in a specific medical treatment; and the other; to chemoprophylatic drugs, both with the same purpose: the accurate selection of the “in vivo” antimicrobial agent. This requires the study of the sensitivity and resistance of strains isolated in both carriers and patients. With the aim of further studying the behavior of the strains that currently circulate in Cuba, an antimicrobial drug susceptibility study was conducted in 90 strains isolated from carriers during the first half of 1998. The agar dilution method was used to determine the minimum inhibitory concentrations (MICs to: penicillin, ampicillin, rifampin, sulfadiazine, chloramphenicol, ciprofloxacin, ceftriaxone, cefotaxime. The study of the three latter drugs was done for the first time in our country. The search for β- lactamase-producer strains was also performed. There was a predominance of penicillin sensitive strains (82,2% with an intermediate sensitivity to ampicillin (57,8%, while 70% of the strains were sensitive to sulfadiazine. Regarding the rest of the antimicrobial drugs, 100% of the strains were sensitive. The paper shows the MICs for each drug as well as the phenotypic characteristics of the strains with the penicillin and sulfadiazine sensitivity and resistance patterns. No β-lactamase-producer strains were found.

  3. Isolation and identification of a novel radio-resistant strain

    International Nuclear Information System (INIS)

    Zhang Zhidong; Mao Jun; Wang Wei; Tang Qiyong; Shi Yuhu

    2008-01-01

    A novel radio-resistant strain named RL2 was studied polyphasically, which was isolated from the soils in the Gurban-Tunggut Desert, Xinjiang. The strain is Gam-positive, sphere-shaped and pink pigmented; The DNA (G+C) contents of RL2 is 71.62mo1%; The 16S rDNA genes of RL2 and D. radiodurans type strain DSM20539 shows a high level of similarity (97.2%). According to phenotypic characteristics and phylogenetic analysis, it can be suggested that the strain RL2 has been identified as Deinococcus. sp and it may be a novel species. (authors)

  4. Molecular characterisation of Mycobacterium caprae strains isolated in Poland.

    Science.gov (United States)

    Krajewska-Wędzina, Monika; Kozińska, Monika; Orłowska, Blanka; Weiner, Marcin; Szulowski, Krzysztof; Augustynowicz-Kopeć, Ewa; Anusz, Krzysztof; Smith, Noel H

    2018-03-10

    Bovine tuberculosis (bovine TB, bTB) is caused by bovine bacilli: Mycobacterium bovis and M caprae The studies conducted in Poland, in the National Bovine Tuberculosis Reference Laboratory in the Department of Microbiology of the National Veterinary Research Institute in Pulawy, show that animal tuberculosis in Poland is also caused by M caprae We here describe the identification and genotypic assessment of 52 isolates of M caprae obtained from Polish cattle and wild animals over the last five years. We show that strains isolated from bison have significant genotypic diversity and are distinct compared with the genotypes of strains isolated from cattle. Similarly, isolates from cattle herds can be highly genotypically variable. Formal designation of the members of the Mycobacterium tuberculosis complex is controversial in Poland; there is a gap in veterinary legislation with regard to bTB and no explicit mention of M caprae causing tuberculosis in animal. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. Progress toward isolation of strains and genetically engineered strains of microalgae for production of biofuel and other value added chemicals: A review

    International Nuclear Information System (INIS)

    Ghosh, Ashmita; Khanra, Saumyakanti; Mondal, Madhumanti; Halder, Gopinath; Tiwari, O.N.; Saini, Supreet; Bhowmick, Tridib Kumar; Gayen, Kalyan

    2016-01-01

    Highlights: • Sample collection, isolation and identification to obtain a pure microalgal species. • Isolation of microalgal strains worldwide based on continent and habitat. • Genetic engineering tools for enhanced production of biodiesel and value added chemicals. • Cultivation systems for genetically modified strain. - Abstract: Microalgae and cyanobacteria are promising sources of biodiesel because of their high oil content (∼10 fold higher) and shorter cultivation time (∼4 fold lesser) than conventional oil producing territorial plants (e.g., soybean, corn and jatropha). These organisms also provide source of several valuable natural chemicals including pigments, food supplements like eicosapentanoic acid [EPA], decosahexaenoic acid [DHA] and vitamins. In addition, many cellular components of these organisms are associated with therapeutic properties like antioxidant, anti-inflammatory, immunostimulating, and antiviral. Isolation and identification of high-yielding strains with the faster growth rate is the key for successful implementation of algal biodiesel (or other products) at a commercial level. A number of research groups in Europe, America, and Australia are thus extensively involved in exploration of novel microalgal strain. Further, genetic engineering provides a tool to engineer the native strain resulting in transgenic strain with higher yields. Despite these efforts, no consensus has yet been reached so far in zeroing on the best microalgal strain for sustainable production of biofuel at reasonable cost. The search for novel microalgal strain and transgenesis of microalgae, are continuing side by side with the hope of commercial scale production of microalgae biofuel in near future. However, no consolidated review report exists which guides to isolate and identify a uncontaminated microalgal strain along with their transgenesis. The present review is focused on: (i) key factors for sample collection, isolation, and identification to

  6. Isolation and characterization of new strains of cholesterol-reducing bacteria from baboons.

    Science.gov (United States)

    Brinkley, A W; Gottesman, A R; Mott, G E

    1982-01-01

    We isolated and characterized nine new strains of cholesterol-reducing bacteria from feces and intestinal contents of baboons. Cholesterol-brain agar was used for the primary isolation, and subsequent biochemical tests were done in a lecithin-cholesterol broth containing plasmenylethanolamine and various substrates. All strains had similar colony and cell morphology, hydrolyzed the beta-glucosides esculin and amygdalin, metabolized pyruvate, and produced acetate and acetoin. Unlike previously reported strains, the nine new strains did not require cholesterol and an alkenyl ether lipid (e.g., plasmalogen) for growth; however, only two strains reduced cholesterol in the absence of the plasmalogen. These two strains also produced succinate as an end product. Carbohydrate fermentation was variable; some strains produced weak acid (pH 5.5 to 6.0) from only a few carbohydrates, whereas other strains produced strong acid reactions (pH less than or equal to 5.5) from a wide variety of carbohydrates.

  7. Molecular characterization of Mycobacterium bovis strains isolated from cattle slaughtered at two abattoirs in Algeria

    Directory of Open Access Journals (Sweden)

    Ouzrout Rachid

    2009-01-01

    Full Text Available Abstract Background Bovine Tuberculosis is prevalent in Algeria despite governmental attempts to control the disease. The objective of this study was to conduct, for the first time, molecular characterization of a population sample of Mycobacterium bovis strains isolated from slaughter cattle in Algeria. Between August and November 2007, 7250 animals were consecutively screened at the abattoirs of Algiers and Blida. In 260 animals, gross visible granulomatous lesions were detected and put into culture. Bacterial isolates were subsequently analysed by molecular methods. Results Altogether, 101 bacterial strains from 100 animals were subjected to molecular characterization. M. bovis was isolated from 88 animals. Other bacteria isolated included one strain of M. caprae, four Rhodococcus equi strains, three Non-tuberculous Mycobacteria (NTM and five strains of other bacterial species. The M. bovis strains isolated showed 22 different spoligotype patterns; four of them had not been previously reported. The majority of M. bovis strains (89% showed spoligotype patterns that were previously observed in strains from European cattle. Variable Number of Tandem Repeat (VNTR typing supported a link between M. bovis strains from Algeria and France. One spoligotype pattern has also been shown to be frequent in M. bovis strains from Mali although the VNTR pattern of the Algerian strains differed from the Malian strains. Conclusion M. bovis infections account for a high amount of granulomatous lesions detected in Algerian slaughter cattle during standard meat inspection at Algiers and Blida abattoir. Molecular typing results suggested a link between Algerian and European strains of M. bovis.

  8. Toxinotyping of Clostridium perfringens strains isolated from packed chicken portions

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    Maryam Poursoltani

    2014-06-01

    Full Text Available Background and Aim: Clostridium perfringens are classified into five toxin types A to E, on the basis of production of Alpha, Beta, Epsilon and Iota toxins. Some strains are able to produce enterotoxin, can cause food poisoning in human. The bacteria are able to produce NetB and TpeL toxins which are virulence factors in necrotic enteritis in poultry. The aim of this study was to determine the toxin profile of C. perfringens strains isolated from packed chicken portions using Single and Multiplex PCR assays. Materials and Methods: In a crossectional study, 180 sample of chicken portions including wing (n=50, liver (n=50, neck (n=50 and gizzard (n=30 were collected randomly and examined for C. perfringens contamination. For this purpose all of samples were cultured on the 7% sheep defibrinated blood agar, TSN and TSC culture media. All of the isolates were investigated for the presence of alpha, beta, epsilon, iota toxin and virulence (tpeL and netB genes. Results: In the present study, 6 isolates out of 180 samples, were confirmed as C. perfringens by culture and molecular methods. All of the isolates (100% were confirmed as cpa and cpb positive strains and belong to type C of C. perfringens. The netB gene was detected in 5 isolates (83.33% and tpeL gene in three isolates (50%. Conclusions: Our findings show the majority of C. perfringens in broilers are belong to type C which produce necrotic enteritis in poultry and may be transmitted to human through poultry products.

  9. Urease-positive thermophilic strains of Campylobacter isolated from seagulls (Larus spp.).

    Science.gov (United States)

    Kaneko, A; Matsuda, M; Miyajima, M; Moore, J E; Murphy, P G

    1999-07-01

    Three strains of urease-positive thermophilic Campylobacter (UPTC), designated A1, A2 and A3, were identified by biochemical characterization after isolation from faeces of seagulls in Northern Ireland in 1996. The biochemical characteristics of the strains were identical to those of strains described previously. Analysis by pulsed-field gel electrophoresis (PFGE) after separate digestion with ApaI and SmaI demonstrated that the respective PFGE profiles were indistinguishable. The PFGE analysis also suggested that the genomes were approximately 1810 kb in length. This is the first example of the isolation of UPTC from flying homoiothermal animals, i.e. from seagulls (Larus spp.).

  10. Antimicrobial properties of lactic acid bacteria isolated from traditional yogurt and milk against Shigella strains.

    Science.gov (United States)

    Zare Mirzaei, Elnaze; Lashani, Elahe; Davoodabadi, Abolfazl

    2018-01-01

    Background: Lactic acid bacteria (LAB) are normal flora of the mouth, intestines and the female genital tract. They are also frequently found in meat, vegetables, and dairy products. Most of probiotic bacteria belong to the LAB group. Some probiotic LAB are useful in prevention and treatment of diarrheal diseases. The aim of this study was to investigate the antimicrobial properties of LAB isolated from traditional yogurt and milk against Shigella strains. Materials and methods: Forty LAB strains were isolated from traditional yogurt and milk. The antimicrobial activity of LAB against Shigella strains (eight S. flexneri , four S. sonnei ) was examined using the agar-well diffusion assay. LAB strains with antimicrobial effect against all Shigella strains were identified by 16S rRNA gene sequencing. Results: Six LAB strains inhibited the growth of all 12 Shigella strains. Lb. paracasei Y1-3, Lb. paracasei Y8-1 and Lb. fermentum Y2-2 were isolated from yogurt. Lb. paracasei M18-1, Lb. parelimentarius M4-3 and Lb. plantarum M19-1 were isolated from milk. Conclusion: This study showed that Lactobacillus strains with good inhibitory activity against S. flexneri and S. sonnei could be isolated from traditional yogurt and milk.

  11. Isolation and identification of biocellulose-producing bacterial strains from Malaysian acidic fruits.

    Science.gov (United States)

    Voon, W W Y; Rukayadi, Y; Meor Hussin, A S

    2016-05-01

    Biocellulose (BC) is pure extracellular cellulose produced by several species of micro-organisms that has numerous applications in the food, biomedical and paper industries. However, the existing biocellulose-producing bacterial strain with high yield was limited. The aim of this study was to isolate and identify the potential biocellulose-producing bacterial isolates from Malaysian acidic fruits. One hundred and ninety-three bacterial isolates were obtained from 19 local acidic fruits collected in Malaysia and screened for their ability to produce BC. A total of 15 potential bacterial isolates were then cultured in standard Hestrin-Schramm (HS) medium statically at 30°C for 2 weeks to determine the BC production. The most potent bacterial isolates were identified using 16S rRNA gene sequence analysis, morphological and biochemical characteristics. Three new and potent biocellulose-producing bacterial strains were isolated from soursop fruit and identified as Stenotrophomonas maltophilia WAUPM42, Pantoea vagans WAUPM45 and Beijerinckia fluminensis WAUPM53. Stenotrophomonas maltophilia WAUPM42 was the most potent biocellulose-producing bacterial strain that produced the highest amount of BC 0·58 g l(-1) in standard HS medium. Whereas, the isolates P. vagans WAUPM45 and B. fluminensis WAUPM53 showed 0·50 and 0·52 g l(-1) of BC production, respectively. Biocellulose (BC) is pure extracellular cellulose that is formed by many micro-organisms in the presence of carbon source and acidic condition. It can replace plant-based cellulose in multifarious applications due to its unique characteristics. In this study, three potential biocellulose-producing bacterial strains were obtained from Malaysian acidic fruits and identified as Stenotrophomonas maltophilia WAUPM42, Pantoea vagans WAUPM45 and Beijerinckia fluminensis WAUPM53. This study reports for the first time the new biocellulose-producing bacterial strains isolated from Malaysian acidic fruits. © 2016 The

  12. CHARACTERIZATION OF EXTENDED-SPECTRUM Β-LACTAMASE-PRODUCING ESCHERICHIA COLI STRAINS ISOLATED FROM DAIRY PRODUCTS

    Directory of Open Access Journals (Sweden)

    Rahem Khoshbakht

    2014-02-01

    Full Text Available Extended-spectrum β-lactamases (ESBLs are enzymes that hydrolyze the β-lactam ring, and ESBL-producing E. coli has rapidly spread worldwide with pose a serious hazard for humans. The aim of this study was to determine the prevalence of ESBL producing E. coli and molecular evaluation of four ESBL-associated genes among E. coli strains isolated from milk and cheese in southern Iran. Antibiotic susceptibility test was carried out for a total of 150 isolates of E. coli, previously collected from dairy products. ESBL production was screened using a double-disc synergy test (DDST and presence of four ESBL genes (PER, VEB, TEM and CTX-M was tested using PCR. Among 150 E. coli strains 57 (38% isolates were identified as ESBL-producing strains. All ESBL positive isolates could be typed for one or more genes and the most prevalent ESBL-associated gene was CTX-M (80.7%. The PER gene was not present among isolates. Isolates showed high susceptibility to imipe¬nem and cefoxitin. The results showed the high prevalence of ESBL producing E. coli strains among dairy products and high occurrence of CTX-M-associated ESBL activity among isolates indicating the hazards of increasing the strains with antibiotic resistance which can transfer to human trough the dairy food products.

  13. Taxonomy of Streptomyces strains isolated from rhizospheres of ...

    African Journals Online (AJOL)

    Taxonomy of Streptomyces strains isolated from rhizospheres of various plant species grown in Taif region, KSA, having antagonistic activities against some microbial tissue ... African Journal of Biotechnology ... Keywords: Taxonomy, Streptomyces, microbial tissue culture contaminants, antagonistic activities, 16S rRNA

  14. Ethanol production potential of local yeast strains isolated from ripe ...

    African Journals Online (AJOL)

    The ability of different yeast strains isolated from ripe banana peels to produce ethanol was investigated. Of the 8 isolates screened for their fermentation ability, 5 showed enhanced performance and were subsequently identified and assessed for important ethanol fermentation attributes such as ethanol producing ability, ...

  15. [Molecular typing of 12 Brucella strains isolated in Guizhou province in 2010-2013].

    Science.gov (United States)

    Wang, Yue; Chen, Hong; Liu, Ying; Zhou, Jingzhu; Li, Shijun; Hang, Yan; Tang, Guangpeng; Wang, Dingming; Chen, Guichun

    2015-09-01

    To identify and characterize the Brucella strains from Guizhou province in 2010-2013. A total of 12 strains of Brucella suspicious bacteria were isolated in Guizhou province from 2010 to 2013. Four strains (GZLL3, GZLL4, GZLL11 and SH2) were isolated from goat blood samples and eight strains (SH4, GZZY, GZSQ, GZZA, BR13001, BR13004, BR13005 and BR13006) were isolated from blood samples of patient 12 Brucella suspicious strains were identified and characterized using conventional methods. Brucella genus specific gene BCSP31-based PCR (BCSP31-PCR) was used to identify the genus of Brucella and IS711 insert sequence-based PCR (AMOS-PCR) was applied to identify the species of Brucella strains. Goats and patients originated Brucella strains were comparatively analysed using Pulse-field Gel Electrophoresis (PFGE). Both of conventional methods and PCR identified the 12 Brucella suspicious strains as B. melitensis biotype 3. BCSP31-PCR identification results showed that a specific DNA bands (223 bp) were detected in all the 12 strains and positive control samples with no DNA band in negative samples. AMOS-PCR amplified a 731 bp-DNA bands in all the 12 strains, with 731 bp, 498 bp and 275 bp in M5, S2 and A19 strains, respectively, and no DNA band was detected in the negative control samples. PFGE analysis showed that 12 Brucella isolates from patients and goats showed consistent PFGE patterns with the digestion of restriction enzyme Xba I. The epidemic species/type of Brucella in both human and animal in Guizhou province was B. melitensis biotype 3 and goat was the main animal source of infection of brucellosis in Guizhou province.

  16. Isolation of Bacterial Strain for Biodegradation of Fats, Oil and Grease

    International Nuclear Information System (INIS)

    Alkhatib, M.F.; Mohd Zahangir Alam; Shabana, H.F.M.

    2015-01-01

    Fat, oil and grease (FOG) deposition is one of the major problems that harm the environment and cause dissatisfaction for human. Uncontrolled and un-pre-treated FOG removal from the kitchen could lead to its accumulation in the piping system. Problems include the interference of fat with the aerobic microorganisms that are responsible in treating the wastewater by reducing oxygen transfer rates and for anaerobic microorganisms; their efficiency could also be reduced due to the reduction of the transport of soluble substrates to the bacterial biomass. Biodegradation could be one of the effective means to treat FOG. The main objective of this study is to isolate bacterial strains from the FOG waste and identify the strains that are capable in biodegrading FOG waste. FOG sample was collected from a sewer manhole. Enrichment technique was applied, followed by isolation of bacterial strains to determine which strain is able to degrade the FOG deposition. Some morphology for the bacterial strain was done to determine its characteristics. (author)

  17. Genetic analysis of Saccharomyces cerevisiae strains isolated from palm wine in eastern Nigeria. Comparison with other African strains.

    Science.gov (United States)

    Ezeronye, O U; Legras, J-L

    2009-05-01

    To study the yeast diversity of Nigerian palm wines by comparison with other African strains. Twenty-three Saccharomyces cerevisiae strains were obtained from palm wine samples collected at four locations in eastern Nigeria, and characterized using different molecular techniques: internal transcribed spacer restriction fragment length polymorphism and sequence analysis, pulsed field gel electrophoresis, inter delta typing and microsatellite multilocus analysis. These techniques revealed that palm wine yeasts represent a group of closely related strains that includes other West African isolates (CBS400, NCYC110, DVPG6044). Population analysis revealed an excess of homozygote strains and an allelic richness similar to wine suggestive of local domestication. Several other African yeast strains were not connected to this group. Ghana sorghum beer strains and other African strains (DBVPG1853 and MUCL28071) displayed strikingly high relatedness with European bread, beer or wine strains, and the genome of strain MUCL30909 contained African and wine-type alleles, indicating its hybrid origin. Nigerian palm wine yeast represents a local specific yeast flora, whereas a European origin or hybrid was suspected for several other Africa isolates. This study presents the first genetic characterization of an autochthonous African palm wine yeast population and confirms the idea that human intervention has favoured yeast migration.

  18. Isolation and characterization of new strains of cholesterol-reducing bacteria from baboons.

    OpenAIRE

    Brinkley, A W; Gottesman, A R; Mott, G E

    1982-01-01

    We isolated and characterized nine new strains of cholesterol-reducing bacteria from feces and intestinal contents of baboons. Cholesterol-brain agar was used for the primary isolation, and subsequent biochemical tests were done in a lecithin-cholesterol broth containing plasmenylethanolamine and various substrates. All strains had similar colony and cell morphology, hydrolyzed the beta-glucosides esculin and amygdalin, metabolized pyruvate, and produced acetate and acetoin. Unlike previously...

  19. Phenotypic and genetic diversity of chlorine-resistant Methylobacterium strains isolated from various environments.

    Science.gov (United States)

    Hiraishi, A; Furuhata, K; Matsumoto, A; Koike, K A; Fukuyama, M; Tabuchi, K

    1995-01-01

    Strains of pink-pigmented facultative methylotrophs which were isolated previously from various environments and assigned tentatively to the genus Methylobacterium were characterized in comparison with authentic strains of previously known species of this genus. Most of the isolates derived from chlorinated water supplies exhibited resistance to chlorine, whereas 29 to 40% of the isolates from air, natural aquatic environments, and clinical materials were chlorine resistant. None of the tested authentic strains of Methylobacterium species obtained from culture collections exhibited chlorine resistance. Numerical analysis of phenotypic profiles showed that the test organisms tested were separated from each other except M. organophilum and M. rhodesianum. The chlorine-resistant isolates were randomly distributed among all clusters. The 16S ribosomal DNA (rDNA) sequence-based phylogenetic analyses showed that representatives of the isolates together with known Methylobacterium species formed a line of descent distinct from that of members of related genera in the alpha-2 subclass of the Proteobacteria and were divided into three subclusters within the Methylobacterium group. These results demonstrate that there is phenotypic and genetic diversity among chlorine-resistant Methylobacterium strains within the genus. PMID:7793931

  20. Phenotypic and genetic diversity of chlorine-resistant Methylobacterium strains isolated from various environments.

    Science.gov (United States)

    Hiraishi, A; Furuhata, K; Matsumoto, A; Koike, K A; Fukuyama, M; Tabuchi, K

    1995-06-01

    Strains of pink-pigmented facultative methylotrophs which were isolated previously from various environments and assigned tentatively to the genus Methylobacterium were characterized in comparison with authentic strains of previously known species of this genus. Most of the isolates derived from chlorinated water supplies exhibited resistance to chlorine, whereas 29 to 40% of the isolates from air, natural aquatic environments, and clinical materials were chlorine resistant. None of the tested authentic strains of Methylobacterium species obtained from culture collections exhibited chlorine resistance. Numerical analysis of phenotypic profiles showed that the test organisms tested were separated from each other except M. organophilum and M. rhodesianum. The chlorine-resistant isolates were randomly distributed among all clusters. The 16S ribosomal DNA (rDNA) sequence-based phylogenetic analyses showed that representatives of the isolates together with known Methylobacterium species formed a line of descent distinct from that of members of related genera in the alpha-2 subclass of the Proteobacteria and were divided into three subclusters within the Methylobacterium group. These results demonstrate that there is phenotypic and genetic diversity among chlorine-resistant Methylobacterium strains within the genus.

  1. Genotypes of Leptospira spp. strains isolated from dogs in Buenos Aires, Argentina.

    Science.gov (United States)

    Grune Loffler, Sylvia; Passaro, Diego; Samartino, Luis; Soncini, Analía; Romero, Graciela; Brihuega, Bibiana

    2014-01-01

    Leptospirosis is an infectious disease of wide global distribution, which is endemic in Argentina. The objective of this study was to obtain the genetic profiles of Leptospira spp. strains isolated from clinical cases of dogs in the province of Buenos Aires by the multiple-locus variable-number tandem repeat analysis (MLVA). Eight isolated canine strains were genotyped by MLVA, obtaining the identical profile of Leptospira interrogans serovar Canicola Hond Utrecht IV in the strains named Dogy and Mayo. The strains named Bel, Sarmiento, La Plata 4581 and La Plata 5478 were identical to the profile of the genotype of L. interrogans serovar Portlandvere MY 1039.The strain named Avellaneda was identical to the genotype profile of L. interrogans serovar Icterohaemorrhagiae RGA and the strain named SB had the same profile as the L. interrogans serovar Pomona Baires genotype and was similar to the profile of serovar Pomona Pomona genotype. It would be useful to include a larger number of isolates from different dog populations in various provinces of Argentina and to characterize the genetic profiles of the strains circulating in the country. The information obtained will be useful for the control of leptospirosis in the dog population. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  2. Genetic transformation of Bacillus strains close to bacillus subtilis and isolated from the soil

    International Nuclear Information System (INIS)

    Van, C.K.; Kuzin, Yu.Yu.; Kozlovskii, Yu.E.; Prozorov, A.A.

    1986-01-01

    Chromosomal and plasmid transformation was found in five out of 118 Bacillus strains, close or identical to Bacillus subtilis, and isolated from soil in Moscow or in the Moscow district. The efficiency of transformation in these strains was lower than that in derivatives of Bac. subtilis strain 168. In these strains the ability to undergo transformation was dependent on the rate of sporulation and the presence of restrictases. As in the case of Bac. subtilis 168 the strains isolated may be used as models in genetic transformation studies on Bac. subtilis

  3. High-frequency rugose exopolysaccharide production by Vibrio cholerae strains isolated in Haiti.

    Directory of Open Access Journals (Sweden)

    Mustafizur Rahman

    Full Text Available In October, 2010, epidemic cholera was reported for the first time in Haiti in over 100 years. Establishment of cholera endemicity in Haiti will be dependent in large part on the continued presence of toxigenic V. cholerae O1 in aquatic reservoirs. The rugose phenotype of V. cholerae, characterized by exopolysaccharide production that confers resistance to environmental stress, is a potential contributor to environmental persistence. Using a microbiologic medium promoting high-frequency conversion of smooth to rugose (S-R phenotype, 80 (46.5% of 172 V. cholerae strains isolated from clinical and environmental sources in Haiti were able to convert to a rugose phenotype. Toxigenic V. cholerae O1 strains isolated at the beginning of the epidemic (2010 were significantly less likely to shift to a rugose phenotype than clinical strains isolated in 2012/2013, or environmental strains. Frequency of rugose conversion was influenced by incubation temperature and time. Appearance of the biofilm produced by a Haitian clinical rugose strain (altered biotype El Tor HC16R differed from that of a typical El Tor rugose strain (N16961R by confocal microscopy. On whole-genome SNP analysis, there was no phylogenetic clustering of strains showing an ability to shift to a rugose phenotype. Our data confirm the ability of Haitian clinical (and environmental strains to shift to a protective rugose phenotype, and suggest that factors such as temperature influence the frequency of transition to this phenotype.

  4. Transport of D-xylose in Lactobacillus pentosus, Lactobacillus casei, and Lactobacillus plantarum: Evidence for a mechanism of facilitated diffusion via the phosphoenolpyruvate:mannose phosphotransferase system

    NARCIS (Netherlands)

    Chaillou, S.; Pouwels, P.H.; Postma, P.W.

    1999-01-01

    We have identified and characterized the D-xylose transport system of Lactobacillus pentosus. Uptake of D-xylose was not driven by the proton motive force generated by malolactic fermentation and required D-xylose metabolism. The kinetics of D-xylose transport were indicative of a low- affinity

  5. Isolation and identification of some Bacillus thuringiensis strains with insecticidal activity against Ceratitis capitata

    International Nuclear Information System (INIS)

    Majdoub, Nihed

    2010-01-01

    The aims of the present work is to study the effect of toxins (delta-endotoxins), extracted from different strains of Bacillus thuringiensis on Ceratitis capitata, a devastating of citrus and fruit trees. Strains of B. thuringiensis were isolated from the mud of Sebket Sejoumi. Among 70 isolates tested, 15 showed a significant identicalness activity in which 5 isolates led to mortality rates ≥ 90 pour cent . These mortality rates are caused by endotoxins of B. thuringiensis. Analysis of proteins profiles of different isolates of B. thuringiensis revealed variability between them. The preliminary results of this study encourage us towards the characterization of the insecticidal activity produced by B. thuringiensis strains for large scale application.

  6. Effect of probiotic microorganisms isolated from Hypostomus plecostomus in Oreochromis sp juveniles

    Directory of Open Access Journals (Sweden)

    Yuri Vela-Gutiérrez

    2017-01-01

    Full Text Available Objective. The aim of this study was to assess the behavior of red tilapia juveniles (Oreochromis sp. in presence of the possible probiotic microorganisms isolated from the gastrointestinal tract of panche fish (Hypostomus plecostomus. Materials and methods. During the phase of assessment of probiotics, 120 red tilapia (Oreochromis sp juveniles were selected, with average weight of 1.28±0.22 g and average length of 2.99±0.27 cm. Three experimental treatments were formulated taking into account the nourishment needs of red tilapia (Oreochromis sp.. The statistical method employed was a completely random design. Results. The three strains of Lactobacillus genus (Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus rhamnosus isolated from the digestive tract of H. plecostomus, yielded diverse results in the biometrical variables considered, as well as in the SGR, PER, AE, AC. Conclusions. The best rapports regarding the gain in length were for the treatment with native probiotics, and it is deduced that they were easily settled in the intestines of the fish (Oreochromis sp.. It is also determined that there are significant differences in the results or gain in length for the Control Concentrate feed (CC against Concentrate feed plus Native Probiotic (CNP for red tilapia (Oreochromis sp. in the juvenile stag for a 30 day time span.

  7. CHARACTERIZATION OF A NEW BACILLUS-STEAROTHERMOPHILUS ISOLATE - A HIGHLY THERMOSTABLE ALPHA-AMYLASE-PRODUCING STRAIN

    NARCIS (Netherlands)

    WIND, RD; BUITELAAR, RM; EGGINK, G; HUIZING, HJ; DIJKHUIZEN, L

    A novel strain of Bacillus stearothermophilus was isolated from samples of a potato-processing industry. Compared to known alpha-amylases from other B. stearothermophilus strains, the isolate was found to produce a highly thermostable alpha-amylase. The half-time of inactivation of this

  8. Variable characteristics of bacteriocin-producing Streptococcus salivarius strains isolated from Malaysian subjects.

    Directory of Open Access Journals (Sweden)

    Abdelahhad Barbour

    Full Text Available BACKGROUND: Salivaricins are bacteriocins produced by Streptococcus salivarius, some strains of which can have significant probiotic effects. S. salivarius strains were isolated from Malaysian subjects showing variable antimicrobial activity, metabolic profile, antibiotic susceptibility and lantibiotic production. METHODOLOGY/PRINCIPAL FINDINGS: In this study we report new S. salivarius strains isolated from Malaysian subjects with potential as probiotics. Safety assessment of these strains included their antibiotic susceptibility and metabolic profiles. Genome sequencing using Illumina's MiSeq system was performed for both strains NU10 and YU10 and demonstrating the absence of any known streptococcal virulence determinants indicating that these strains are safe for subsequent use as probiotics. Strain NU10 was found to harbour genes encoding salivaricins A and 9 while strain YU10 was shown to harbour genes encoding salivaricins A3, G32, streptin and slnA1 lantibiotic-like protein. Strain GT2 was shown to harbour genes encoding a large non-lantibiotic bacteriocin (salivaricin-MPS. A new medium for maximum biomass production buffered with 2-(N-morpholinoethanesulfonic acid (MES was developed and showed better biomass accumulation compared with other commercial media. Furthermore, we extracted and purified salivaricin 9 (by strain NU10 and salivaricin G32 (by strain YU10 from S. salivarius cells grown aerobically in this medium. In addition to bacteriocin production, S. salivarius strains produced levan-sucrase which was detected by a specific ESI-LC-MS/MS method which indicates additional health benefits from the developed strains. CONCLUSION: The current study established the bacteriocin, levan-sucrase production and basic safety features of S. salivarius strains isolated from healthy Malaysian subjects demonstrating their potential for use as probiotics. A new bacteriocin-production medium was developed with potential scale up application for

  9. Title: High-level cefotaxime-resistant Proteus mirabilis strain isolated ...

    African Journals Online (AJOL)

    oaca

    High-level cefotaxime-resistant Proteus mirabilis strain isolated from a Tunisian .... UV- visible) at 37°C. Specific activity is calculated on depending of. Ross and ..... Performance standards for antimicrobial susceptibility testing;. Seventeenth ...

  10. Complete Genome Sequence of Porcine Parvovirus N Strain Isolated from Guangxi, China

    OpenAIRE

    Su, Qian-Lian; Li, Bin; Zhao, Wu; Liang, Jia-Xing; He, Ying; Qin, Yi-Bin; Lu, Bing-Xia

    2015-01-01

    We report here the complete genomic sequence of the porcine parvovirus (PPV) N strain, isolated in 1989 from the viscera of a stillborn fetus farrowed by a gilt in Guangxi, southern China. Phylogenetic analyses suggest that the PPV-N strain is closely related to attenuated PPV NADL-2 strains. The PPV-N strain has good immunogenicity, genetic stability, and safety.

  11. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    Science.gov (United States)

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

  12. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    Directory of Open Access Journals (Sweden)

    Boutheina Gargouri

    2015-01-01

    Full Text Available Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.

  13. Genomic differentiation among two strains of the PS1 clade isolated from geographically separated marine habitats

    KAUST Repository

    Jimenez Infante, Francy M.; Ngugi, David; Alam, Intikhab; Rashid, Mamoon; Ba Alawi, Wail; Kamau, Allan; Bajic, Vladimir B.; Stingl, Ulrich

    2014-01-01

    Using dilution-to-extinction cultivation, we isolated a strain affiliated with the PS1 clade from surface waters of the Red Sea. Strain RS24 represents the second isolate of this group of marine Alphaproteobacteria after IMCC14465 that was isolated

  14. Genome Sequence of Campylobacter jejuni strain 327, a strain isolated from a turkey slaughterhouse

    DEFF Research Database (Denmark)

    Takamiya, Monica; Özen, Asli Ismihan; Rasmussen, Morten

    2011-01-01

    , catalase positive bacterium obtains energy from the metabolism of amino acids and Krebs cycle intermediates. Strain 327 was isolated from a turkey slaughter production line and is considered environmentally sensitive to food processing (cold, heat, drying) and storage conditions. The 327 whole genome...

  15. Full genome sequence of a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007

    DEFF Research Database (Denmark)

    Afzal, Mamuna; Abidi, Soad; Mikkelsen, Heidi

    We have sequenced a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007. The strain was isolated from faecal material of a 48 month old second parity Danish Holstein cow, with clinical symptoms of chronic diarrhoea and emaciation. The cultures were grown on Löwen......We have sequenced a Danish isolate of Mycobacterium avium subspecies paratuberculosis, strain Ejlskov2007. The strain was isolated from faecal material of a 48 month old second parity Danish Holstein cow, with clinical symptoms of chronic diarrhoea and emaciation. The cultures were grown......, consisting of 4317 unique gene families. Comparison with M. avium paratuberculosis strain K10 revealed only 3436 genes in common (~70%). We have used GenomeAtlases to show conserved (and unique) regions along the Ejlskov2007 chromosome, compared to 2 other Mycobacterium avium sequenced genomes. Pan......-genome analyses of the sequenced Mycobacterium genomes reveal a surprisingly open and diverse set of genes for this bacterial genera....

  16. NEW PRODUCER STRAINS OF BIOBUTANOL. І. ISOLATION AND IDENTIFICATION

    Directory of Open Access Journals (Sweden)

    O. A. Tigunova

    2013-02-01

    Full Text Available Getting new, more productive strains of microorganisms that produce butanol is a topical problem. Studing of morphological and physiological characteristics of the isolated strains, improvement of their cultivation conditions, optimization of biobutanol synthesis gives the possibility to organize a cost-effective butanol production technology. The aim of this work was searching new butanol and butyric acid producer strains, their identification and studying the main steps of the selective strains biosynthesis. The objects of this study were microorganisms that had allocated from soils and sludges samples of Kiev’s lakes. Obtained cultures have been screened. Three strains were obtained as promising and identified as C. acetobutylicum, C. tyrobutylicum, C. butylicum. Selective medium have been developed and modified for the microorganisms. Producer’s features were investigated in order to maximize the accumulation of target metabolites.

  17. Complete genome sequence of porcine parvovirus N strain isolated from guangxi, china.

    Science.gov (United States)

    Su, Qian-Lian; Li, Bin; Zhao, Wu; Liang, Jia-Xing; He, Ying; Qin, Yi-Bin; Lu, Bing-Xia

    2015-01-08

    We report here the complete genomic sequence of the porcine parvovirus (PPV) N strain, isolated in 1989 from the viscera of a stillborn fetus farrowed by a gilt in Guangxi, southern China. Phylogenetic analyses suggest that the PPV-N strain is closely related to attenuated PPV NADL-2 strains. The PPV-N strain has good immunogenicity, genetic stability, and safety. Copyright © 2015 Su et al.

  18. Susceptibility to tigecycline of Acinetobacter baumannii strains isolated from intensive care unit patients.

    Science.gov (United States)

    Talaga, Katarzyna; Krzyściak, Paweł; Bulanda, Małgorzata

    2016-01-01

    Infections caused by Acinetobacter baumannii are difficult to cure due to the acquisition of resistance by these bacteria and lead to an increase in the general costs of hospitalization. The aim of this study was to determine tigecycline susceptibility of Acinetobacter baumannii strains isolated from intensive care unit and non-intensive care unit patients with skin and soft tissue infections. MICs were tested by Etest among 70 Acinetobacter baumannii isolates. The MIC range was from 0.5 to 8.0 mg L⁻¹. For ESBL-producing Acinetobacter baumannii, as well as for strains without carbapenemases, the highest MIC to tigecycline value was 8.0 mg L⁻¹. For AmpC-producing Acinetobacter baumannii, the highest MIC to tigecycline value was 6.0 mg L⁻¹ and, for MBL-producing strains, 2.0 mg L⁻¹. The majority of Acinetobacter baumannii strains isolated from ICU and non-ICU patients demonstrated high values of MIC range, MIC50 and MIC90 to tigecycline.

  19. Immunodominant antigens of Helicobacter pylori strains isolated from patients with different gastroduodenal diseases

    International Nuclear Information System (INIS)

    Farshad, S.; Alborzi, A.; Japoni, A.; Hayati, M.; Nasiri, J.; Rafatpour, N.; Saberfirouzi, M.; Lankarani, Kamran B.; Taghavi, Ali R.; Irajian, Gholam R.

    2006-01-01

    To detect the immunogenic proteins in Helicobacter pylori (H. pylori) strains isolated from patients with different gastric diseases. We performed this study in the Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran, during July 2003 to September 2004. Total proteins of H. pylori strains isolated from the gastric biopsies of 3 groups of patients were separated by 1D-SDS-PAGE and then blotted with the sera of their respective hosts. In SDS-PAGE the members of each group showed high correlation according to similarity in their patterns, resulting in considering them in the same cluster. The patterns of immunoblots differed from that of Coomassie Brilliant Blue stained gels. The blotting method did not recognize some of the protein bands in the SDS-PAGE. Only the bands of 106 and 45 kDa from H. pylori strains isolated from patients with gastric cancer were significantly (p<0.05) recognized specifically with the sera of their respective patients, and the band of 13 kDa was recognized specifically (p<0.05) with the sera of nonulceric patients. With the exception of these bands, in the patterns of blotting of the sera from all patients no significant differences were observed. By using 1D blotting methods we could find 2 antigenic protein bands (106 and 45 kDa) for H. pylori strains isolated from cancerous patients, and one (13 kDa) for the strains isolated from nonulceric patients, which were specifically recognized with their respective host. (author)

  20. Occurrence of mannose resistant hemagglutinins in Escherichia coli strains isolated from porcine colibacillosis.

    Science.gov (United States)

    Truszczyński, M; Osek, J

    1987-01-01

    Three-hundred and fifty-eight E. coli strains isolated from piglets were tested for the presence of hemagglutinins by the use of the active hemagglutination test with or without mannose. Additionally 86 strains from the mentioned number of strains were investigated for the presence of common fimbriae using the same method but growing the strains in media especially suited for the development of this kind of fimbriae. These 358 strains and additionally 202 E. coli strains were tested using antisera for 987P and K88 antigens. It was found, using the active hemagglutination test, that 51.4% of the strains were hemagglutinating. The hemagglutinating strains carried the K88 antigen. All these strains were isolated from new-born and weaned piglets with enterotoxic form of colibacillosis, called also E. coli diarrhea. From cases of this form of colibacillosis originated also 26.7% of the strains in which common fimbriae (type 1) were detected. This result was obtained when the BHI medium was used for cultivation. In case of TSA medium only 2.3% of strains were positive. No specific or common fimbriae were found in strains recovered from septic form of colibacillosis and oedema disease (called also enterotoxaemic form of colibacillosis). No strain of 560 examined showed the presence of fimbrial 987P antigen.

  1. Isolation of non-sulphur photosynthetic bacterial strains efficient in hydrogen production at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Srivastava, S.C. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

    1991-01-01

    Four strains of non-sulphur photosynthetic bacteria were isolated from root zone associations of aquatic plants like Azolla, Salvinia and Eichhornia, as well as the deep-water rice. Based on the gross cell morphology and pigmentation, the isolates resembled Rhodopseudomonas sp. and have been designated as BHU strains 1 to 4, respectively. When subjected to elevated temperature (from 33-45{sup o}C), substantial growth/hydrogen production could be observed only in strains 1 and 4. Strains 2 and 3 on the other hand, showed diminished growth and negligible hydrogen photoproduction. The BHU strains 1 and 4 have been selected as the most active (thermostable) hydrogen producing strains of local origin as far as the Indian tropical climate is concerned. (author).

  2. Three draft genomes of Vibrio coralliilyticus strains isolated from bivalve hatcheries

    Science.gov (United States)

    Reported here are the draft genomes of three Vibrio coralliilyticus isolates RE87, AIC-7, and 080116A. Each strain was isolated in association with diseased oyster larvae in commercial aquaculture systems. These draft genomes will be useful for further studies in understanding the genomic features...

  3. Spoilage potential of brettanomyces bruxellensis strains isolated from Italian wines.

    Science.gov (United States)

    Guzzon, Raffaele; Larcher, Roberto; Guarcello, Rosa; Francesca, Nicola; Settanni, Luca; Moschetti, Giancarlo

    2018-03-01

    Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B. bruxellensis population investigated. All strains were evaluated for their growth ability in the presence of ethanol, high sugar content, low pH, different temperatures and sulphur dioxide, using optical density and flow cytometry measurement. The ability of yeasts to produce ethyl phenols in red wines with different chemical compositions was evaluated by means of high performance liquid chromatography with electrochemical detection (HPLC-ECD). The results highlighted wide variability in B. bruxellensis in response to wine limiting factors and in terms of the accumulation of ethyl phenols. As regards this last aspect, the differences found among strains were closely related to chemical composition of wine and strain resistance to environmental stress factors, making a priori evaluation of risk of wine alteration quite difficult. These results suggest that strategies for the control of Brettanomyces should be tailored on the basis of strain distribution and wine characteristics. Copyright © 2017. Published by Elsevier Ltd.

  4. Antibiotic susceptibility of Lactobacillus strains isolated from domestic geese.

    Science.gov (United States)

    Dec, M; Wernicki, A; Puchalski, A; Urban-Chmiel, R

    2015-01-01

    The aim of this study was to determine the antibiotic susceptibility of 93 Lactobacillus strains isolated from domestic geese raised on Polish farms. The minimal inhibitory concentration (MIC) of 13 antimicrobial substances was determined by the broth microdilution method. All strains were sensitive to the cell wall inhibitors ampicillin and amoxicillin (MIC ≤ 8 μg/ml). Resistance to inhibitors of protein synthesis and to fluoroquinolone inhibitors of replication was found in 44.1% and 60.2% of isolates, respectively; 26.9% strains were resistant to neomycin (MIC ≥ 64 μg/ml), 23.6% to tetracycline (MIC ≥ 32 μg/ml), 15% to lincomycin (MIC ≥ 64 μg/ml), 18.3% to doxycycline (MIC ≥ 32 μg/ml), 9.7% to tylosin (MIC ≥ 32 μg/ml), 56% to flumequine (MIC ≥ 256 μg/ml) and 22.6% to enrofloxacin (MIC ≥ 64 μg/ml). Bimodal distribution of MICs indicative of acquired resistance and unimodal distribution of the high MIC values indicative of intrinsic resistance were correlated with Lactobacillus species. Eleven (11.8%) strains displayed multiple resistance for at least three classes of antibiotics. Data derived from this study can be used as a basis for reviewing current microbiological breakpoints for categorisation of susceptible and resistant strains of Lactobacillus genus and help to assess the hazards associated with the occurrence of drug resistance among natural intestinal microflora.

  5. A strain-isolation design for stretchable electronics

    Science.gov (United States)

    Wu, Jian; Li, Ming; Chen, Wei-Qiu; Kim, Dae-Hyeong; Kim, Yun-Soung; Huang, Yong-Gang; Hwang, Keh-Chih; Kang, Zhan; Rogers, John A.

    2010-12-01

    Stretchable electronics represents a direction of recent development in next-generation semiconductor devices. Such systems have the potential to offer the performance of conventional wafer-based technologies, but they can be stretched like a rubber band, twisted like a rope, bent over a pencil, and folded like a piece of paper. Isolating the active devices from strains associated with such deformations is an important aspect of design. One strategy involves the shielding of the electronics from deformation of the substrate through insertion of a compliant adhesive layer. This paper establishes a simple, analytical model and validates the results by the finite element method. The results show that a relatively thick, compliant adhesive is effective to reduce the strain in the electronics, as is a relatively short film.

  6. Full genome sequences and molecular characterization of tick-borne encephalitis virus strains isolated from human patients.

    Science.gov (United States)

    Formanová, Petra; Černý, Jiří; Bolfíková, Barbora Černá; Valdés, James J; Kozlova, Irina; Dzhioev, Yuri; Růžek, Daniel

    2015-02-01

    Tick-borne encephalitis virus (TBEV) causes tick-borne encephalitis (TBE), one of the most important human neuroinfections across Eurasia. Up to date, only three full genome sequences of human European TBEV isolates are available, mostly due to difficulties with isolation of the virus from human patients. Here we present full genome characterization of an additional five low-passage TBEV strains isolated from human patients with severe forms of TBE. These strains were isolated in 1953 within Central Bohemia in the former Czechoslovakia, and belong to the historically oldest human TBEV isolates in Europe. We demonstrate here that all analyzed isolates are distantly phylogenetically related, indicating that the emergence of TBE in Central Europe was not caused by one predominant strain, but rather a pool of distantly related TBEV strains. Nucleotide identity between individual sequenced TBEV strains ranged from 97.5% to 99.6% and all strains shared large deletions in the 3' non-coding region, which has been recently suggested to be an important determinant of virulence. The number of unique amino acid substitutions varied from 3 to 9 in individual isolates, but no characteristic amino acid substitution typical exclusively for all human TBEV isolates was identified when compared to the isolates from ticks. We did, however, correlate that the exploration of the TBEV envelope glycoprotein by specific antibodies were in close proximity to these unique amino acid substitutions. Taken together, we report here the largest number of patient-derived European TBEV full genome sequences to date and provide a platform for further studies on evolution of TBEV since the first emergence of human TBE in Europe. Copyright © 2014 Elsevier GmbH. All rights reserved.

  7. Genotyping of Methicillin Resistant Staphylococcus aureus Strains Isolated from Hospitalized Children

    Directory of Open Access Journals (Sweden)

    Mouna Ben Nejma

    2014-01-01

    Full Text Available Community associated methicillin resistant Staphylococcus aureus (CA-MRSA is an emerging pathogen increasingly reported to cause skin and soft tissue infections for children. The emergence of highly virulencet CA-MRSA strains in the immunodeficiency of young children seemed to be the basic explanation of the increased incidence of CA-MRSA infections among this population. The subjects of this study were 8 patients hospitalized in the Pediatric Department at the University Hospital of Monastir. The patients were young children (aged from 12 days to 18 months who were suffering from MRSA skin infections; two of them had the infections within 72 h of their admission. The isolates were classified as community isolates as they all carried the staphylococcal cassette chromosome mec (SCCmec IV and pvl genes. Epidemiological techniques, pulsed-field gel electrophoresis (PFGE and multilocus sequence typing (MLST, were applied to investigate CA-MRSA strains. Analysis of molecular data revealed that MRSA strains were related according to PFGE patterns and they belonged to a single clone ST80. Antimicrobial susceptibility tests showed that all strains were resistant to kanamycin and 2 strains were resistant to erythromycin.

  8. Functional Properties of Lactobacillus mucosae Strains Isolated from Brazilian Goat Milk.

    Science.gov (United States)

    de Moraes, Georgia Maciel Dias; de Abreu, Louricélia Rodrigues; do Egito, Antônio Silvio; Salles, Hévila Oliveira; da Silva, Liana Maria Ferreira; Nero, Luís Augusto; Todorov, Svetoslav Dimitrov; Dos Santos, Karina Maria Olbrich

    2017-09-01

    The search for probiotic candidates among lactic acid bacteria (LAB) isolated from food may uncover new strains with promising health and technological properties. Lactobacillus mucosae strains attracted recent research attention due to their ability to adhere to intestinal mucus and to inhibit pathogens in the gastrointestinal tract, both related to a probiotic potential. Properties of interest and safety aspects of three Lb. mucosae strains (CNPC006, CNPC007, and CNPC009) isolated from goat milk were investigated employing in vitro tests. The presence of genetic factors related to bile salt hydrolase production (bsh), intestinal adhesion properties (msa, map, mub, and ef-tu), virulence, and biogenic amine production were also verified. All strains exhibited the target map, mub, and ef-tu sequences; the msa gene was detected in CNPC006 and CNPC007 strains. Some of the searched sequences for virulence factors were detected, especially in the CNPC009 strain; all strains carried the hyl gene, related to the production of hyaluronidase. Lb. mucosae CNPC007 exhibited a high survival rate in simulated gastric and enteric conditions. Besides, all strains exhibited the bsh sequence, and CNPC006 and CNPC007 were able to deconjugate salts of glycodeoxycholic acid (GDC). Regarding technological properties for dairy product applications, a relatively higher milk acidification and clotting capacity, diacetyl production, and proteolytic activity were registered for CNPC007 in comparison to the other strains. Collectively, the results aim at Lb. mucosae CNPC007 as a promising probiotic candidate for application in dairy products, deserving further studies to confirm and explore its potential.

  9. Rapid Evaluation of Bacteriolysis of Listeria innocua and L. welshimeri Strains Isolated from Foods

    OpenAIRE

    ÇETİNKAYA, Figen; ÇIBIK, Recep

    2014-01-01

    This study was performed to determine the bacteriolytic extent of 10 strains of Listeria innocua and 9 strains of L. welshimeri isolated from foods. Bacteriolysis was measured at 650 nm by spectrophotometer. For this purpose, late exponential phase cells were transferred into potassium phosphate buffer (100 mM, pH 7.0) and incubated at 37 ºC. While the bacteriolysis range of L. innocua strains was 48% to 76% after 48 h of incubation, L. welshimeri isolates exhibited broader bacteriolytic vari...

  10. Experimental mouse lethality of Escherichia coli strains isolated from free ranging Tibetan yaks.

    Science.gov (United States)

    Rehman, Mujeeb Ur; Zhang, Hui; Wang, Yajing; Mehmood, Khalid; Huang, Shucheng; Iqbal, Muhammad Kashif; Li, Jiakui

    2017-08-01

    The present study has examined the virulence potential of Escherichia coli isolates harboring at least one virulence gene (associated with ExPEC or InPEC pathotype and belonging to different phylogenetic groups: A, B1, B2 or D), isolated from free ranging Tibetan yak feces. The E. coli isolates (n = 87) were characterized for different serogroups and a mouse model of subcutaneous-infection was used to envisage the virulence within these E. coli strains. Of the 87 E. coli isolates examined, 23% of the E. coli isolates caused lethal infections in a mouse model of subcutaneous infection and were classified as killer. Moreover, the majority of the killer strains belonged to phylogroup A (65%) and serogroup O 60 or O 101 (35%). Phylogroup B1, serogroups O 60 and O 101 were statistically associated with the killer status (P 1) were observed between the killer status isolates and all other bacterial virulence traits. This study comprises the first report on the virulence potential of E. coli strains isolated from free-ranging Tibetan yaks feces. Our findings suggest that pathogenic E. coli of free ranging yaks is highly worrisome, as these feces are used as manures by farmers and therewith pose a health risk to humans upon exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Pathogenic strains of Yersinia enterocolitica isolated from domestic dogs (Canis familiaris) belonging to farmers are of the same subtype as pathogenic Y. enterocolitica strains isolated from humans and may be a source of human infection in Jiangsu Province, China.

    Science.gov (United States)

    Wang, Xin; Cui, Zhigang; Wang, Hua; Tang, Liuying; Yang, Jinchuan; Gu, Ling; Jin, Dong; Luo, Longze; Qiu, Haiyan; Xiao, Yuchun; Xiong, Haiping; Kan, Biao; Xu, Jianguo; Jing, Huaiqi

    2010-05-01

    We isolated 326 Yersinia enterocolitica strains from 5,919 specimens from patients with diarrhea at outpatient clinics, livestock, poultry, wild animals, insect vectors, food, and the environment in the cities of Nantong and Xuzhou in Jiangsu Province, China, from 2004 to 2008. The results showed that the 12 pathogenic strains were of the O:3 serotype. Six strains were isolated from domestic dogs (Canis familiaris) belonging to farmers and were found to be the primary carriers of pathogenic Y. enterocolitica strains, especially in Xuzhou. Pulsed-field gel electrophoresis analysis of the pathogenic strains from dogs belonging to farmers showed that they shared the same patterns as strains from diarrhea patients isolated in 1994. This indicates that the strains from domestic dogs have a close correlation with the strains causing human infections.

  12. Complete Genome Sequences of Getah Virus Strains Isolated from Horses in 2016 in Japan.

    Science.gov (United States)

    Nemoto, Manabu; Bannai, Hiroshi; Ochi, Akihiro; Niwa, Hidekazu; Murakami, Satoshi; Tsujimura, Koji; Yamanaka, Takashi; Kokado, Hiroshi; Kondo, Takashi

    2017-08-03

    Getah virus is mosquito-borne and causes disease in horses and pigs. We sequenced and analyzed the complete genomes of three strains isolated from horses in Ibaraki Prefecture, eastern Japan, in 2016. They were almost identical to the genomes of strains recently isolated from horses, pigs, and mosquitoes in Japan. Copyright © 2017 Nemoto et al.

  13. Isolation of pathogenic Yersinia enterocolitica strains from different sources in Izmir region, Turkey.

    Science.gov (United States)

    Bozcal, Elif; Uzel, Atac; Aydemir, Sohret; Skurnik, Mikael

    2015-11-01

    Yersinia enterocolitica is a foodborne pathogen that is very rarely encountered in Turkey. In this work, several human, porcine, and environmental samples collected from Izmir region in Turkey were examined for the presence of Y. enterocolitica using different cultivation and enrichment methods. A total of nine pathogenic Y. enterocolitica strains were isolated; five strains from pig stool and manure samples and four strains from waste water samples. On the other hand, no Y. enterocolitica was isolated from human diarrheal stool samples (n = 102) and from 12 gulf, canal, municipal pool, and well water samples. Biochemical and serological characterization of the nine Y. enterocolitica strains revealed that they belonged to three different bioserotypes: 4/O:3, 2/O:9, and 2/O:5,27. All the strains were deemed pathogenic based on virulence factor-specific PCR analysis. Detection of pathogenic Y. enterocolitica strains from the pig and waste water samples from the Izmir region indicates that Y. enterocolitica is a potential risk for public health.

  14. Temporal association between the isolation of Sabin-related poliovirus vaccine strains and the Guillain-Barré syndrome

    Directory of Open Access Journals (Sweden)

    F. Friedrich

    1996-02-01

    Full Text Available Thirty eight paralysis cases classified as Guillain-Barré syndrome (GBS in Brazil were analysed. In all these cases Sabin-related poliovirus vaccine strains were isolated. In most of the cases the last vaccine dose was given months or years before the onset of GBS, suggesting a persistent infection or the transmission of the Sabin-related strains to the patients. The isolation of Sabin-related strains from GBS cases some days or weeks after the onset of the disease, demonstrated a temporal association between the isolation of the strains and the disease. Although the isolates from the GBS cases may not be the etiological agent of the disease, this study strongly indicates that infections caused by Sabin-related vaccine strains can trigger the GBS in certain cases.

  15. Isolation of perchlorate-reducing Azospira suillum strain JB524 from tidal flats of the Yellow Sea

    Directory of Open Access Journals (Sweden)

    Nirmala Bardiya

    2016-11-01

    Full Text Available Objective: To isolate and identify perchlorate-reducing bacterium from an enriched consortium from tidal flats of the Yellow Sea. Methods: A perchlorate-enriched consortium from tidal flats of the Yellow Sea was used to isolate Azospira suillum (A. suillum strain JB524. The strain was identified based on partial 16S rDNA sequencing. Perchlorate reduction by the strain was tested with acetate as the e - donor in the presence of NaCl, nitrate and at different growth temperatures using standard anaerobic techniques. The complete enzymatic destruction of perchlorate was confirmed as evolution of O2 by chlorite dismutase in the absence of acetate. Results: Strain JB524 shared 100% 16S rDNA sequence similarity with the type strain A. suillum PST isolated from a swine waste treatment lagoon. Perchlorate reduction coincided with concomitant increase in cell density. Although, acclimatization of the strain PST at suboptimal temperature for perchlorate reduction is not reported, the newly isolated strain could rapidly reduce perchlorate at 22 °C after brief acclimatization. Conclusions: Reduction of perchlorate by A. suillum strain JB524 was negatively affected in the presence of NaCl, suboptimal temperature, presence of nitrate, and limiting amount of acetate as the e-donor.

  16. Isolation of Klebsiella pneumoniae strains with altered susceptibility to carbapenems not carbapenemase mediated

    Directory of Open Access Journals (Sweden)

    Franca Cian

    2009-12-01

    Full Text Available The spread of enterobacteria producing extended-spectrum ß-lactamases (ESBLs is sharply increasing in Italy, while the detection of isolates resistant to carbapenems is still sporadic. Isolates of Klebsiella pneumoniae resistant to all cephalosporins, aminoglycosides and fluoroquinolones have been isolated in Trieste since 2008. Because of the altered profile of resistance to carbapenems, these strains were reported as ESBL-negative and possible carbapenemases producer by the expert system, leaving tigecycline as the only therapeutic choice.The purpose of this study is the characterization of the mechanisms involved in resistance to carbapenems in these strains and the evaluation of a reliable and simple test for phenotypic confirmation of ESBL and/or carbapenemase production. 25 isolates of MDR K. pneumoniae were collected between October 2008 and May 2009, mainly from urinary samples of elderly patients hospitalized in medicine wards. Identification and susceptibility testing were performed using the Vitek 2 system.The double-disc (DD test was used to check the production of ESBLs, while imipenem and imipenem-EDTA synergy test was used to detect the production of metallo-ßlactamase (MBL. Carbapenemase activity was tested by an hydrolysis assay and the production of MBLs was also investigated by PCR. The DD synergy test highlighted the possible production of ESBLs in 18 out of 22 strains, considered as negative by Vitek. All ESBLs producers tested positive for the blaCTX-M-15 allele. Only one isolate was resistant to carbapenems and resulted positive for production of MBL by the phenotypic test.The crude extract showed carbapenemase activity inhibited by EDTA; PCR test gave positive result for a blaVIM-type allele. PCR analysis performed on representative isolates, followed by sequencing, showed that coding sequence of ompk35 was not functional. Results of this study confirmed the emergence of ESBL-positive strains of K. pneumoniae that

  17. Antibacterial activity of Achillea tenuifolia Lam. extract against standard bacteria and isolated strains

    Directory of Open Access Journals (Sweden)

    Sahar Omidpanah

    2016-12-01

    Full Text Available Researchers have been trying to develop new broad-spectrum antibiotics against the infectious diseases caused by bacteria, fungi, viruses, and parasites for many decades. Prolonged usage of the antibiotics has led to the emergence of drug resistance among bacteria; therefore, there is a tremendous need for novel antimicrobial agents from different sources such as plants which are used in traditional medicine. The aim of this study was to evaluate antibacterial effect of Achillea tenuifolia. The plant material was extracted by maceration method using methanol three times at room temperature. The extract was concentrated after removing the solvent by rotary evaporator and then lyophilized using freeze dryer. Inhibitory effect of the extract was examined against four standard bacteria strains and two isolated strains from diseased hen using disk diffusion method and microdilution method to evaluate their inhibition zone diameter (IZD and minimum inhibitory concentration (MIC, respectively. The results showed that the extract of the plant was active against standard strains including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis with IZDs of 10.3±0.5, 14±0.0, 12±0.0 and 11.6±0.5, respectively. However, growths of isolated strains were not inhibited in the presence of the extract. Although, the growths of isolated strains were not inhibited by the plant extract, the standard strains were moderately susceptible to the extract; among those P. aeroginosa was more sensible than other tested strains

  18. Molecular Detection of Inducible Clindamycin Resistance among Staphylococcal Strains Isolated from Hospital Patients

    Directory of Open Access Journals (Sweden)

    Shadiyeh Abdollahi

    2013-04-01

    Full Text Available Background & Objectives: Macrolide, lincosamide and streptogramin B (MLSB antimicrobial agents are used in the treatment of staphylococcal infections. They prevent the microbial protein synthesis system through binding to 23 S rRNA. The aim of this study was to apply molecular methods to detect inducible clindamycin resistance genes among staphylococcal strains isolated from clinical specimens.   Methods : Two hundred staphylococcus strains were isolated from nose and throat swabs of patients in Toohid and Besat hospitals in Sanandaj . Antimicrobial susceptibilities of isolates were determined using disc diffusion method, agar screen test and D-Test. A multiplex PCR was performed using primers specific for erm (A, B, C, TR genes.   Results: Out of 200 isolates, 18.5 % were MRSA and 32% were MRCNS (methicillin resistant coagulase negative staphylococci. Of 80 erythromycin resistant isolates, 48 were coagulase negative and 32 were S. aureus. Among the 48 coagulase negative staphylococci (CONS isolates, 11.63% expressed the MLSB-inducible phenotypes. Using PCR, the frequency of different genes in the collection of isolates were as follows: ermA 5.41 % , erm B 5.41 % , and erm C 3.13%. The ermTR gene was negative in all isolates. Among the 32 S. aureus isolates, 9.38% expressed the MLSB-nducible phenotype. Using PCR, these isolates harbored erm A (2.22%, ermB (2.22%, ermC (2.22% and ermTR (2.22% .   Conclusion: This is the first study to show the rate of inducible clindamycin clinical isolates of staphylococci harboring erm genes in Sananadaj. It also demonstrated the frequency of erm genes was higher among CONS isolates than S. aureus. This data suggested the transfer of resistance gene from nonpathogenic to pathogenic strains is likely to happen. Therefore, screening and control of these resistance genes is recommended at clinical laboratories.

  19. Isolation and screening of strains producing high amounts of rutin degrading enzymes from Fagopyrum tataricum seeds.

    Science.gov (United States)

    Zheng, Ya-Di; Luo, Qing-Lin; Zhou, Mei-Liang; Wang, De-Zhou; Zhang, Ye-Dong; Shao, Ji-Rong; Zhu, Xue-Mei; Tang, Yu

    2013-02-01

    The rutin degrading enzyme (RDE) was isolated and purified from tartary buckwheat seeds. The RDE was purified about 11.34-fold and its final yield was 3.5%, which was very low, due to our purification strategy of giving priority to purity over yield. The RDE molecular weight was estimated to be about 60 kDa. When rutin was used as substrate, an optimal enzyme activity was seen at around pH 5.0 and 40 °C. Strains isolation strategy characterized by the use of rutin as sole carbon source in enrichment cultures was used to isolate RDE-producing strains. Then the active strains were identified by morphology characterization and 18s rDNA-ITS (Internal Transcribed Spacer) gene sequencing. Three isolates coded as B3, W2, Y2 were successfully isolated from fusty Fagopyrum tataricum flour cultures. Strain B3 possessed the highest unit activity among these three strains, and its total activity reached up to 171.0 Unit. The active isolate (B3) could be assigned to Penicillium farinosum. When the Penicillium farinosum strains were added to tartary buckwheat flour cultures at pH 5.0, 30 °C after 5 days fermentation, the quercetin production raised up to 1.78 mg/l, almost 5.1 times higher than the fermentation without the above active strains. Hence, a new approach was available to utilize microorganism-aided fermentation for effective quercetin extraction from Fagopyrum tataricum seeds. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Probiotic Potential of Lactobacillus Strains with Antifungal Activity Isolated from Animal Manure

    OpenAIRE

    Ilavenil, Soundharrajan; Park, Hyung Soo; Vijayakumar, Mayakrishnan; Valan Arasu, Mariadhas; Kim, Da Hye; Ravikumar, Sivanesan; Choi, Ki Choon

    2015-01-01

    The aim of the study was to isolate and characterize the lactic acid bacteria (LAB) from animal manure. Among the thirty LAB strains, four strains, namely, KCC-25, KCC-26, KCC-27, and KCC-28, showed good cell growth and antifungal activity and were selected for further characterization. Biochemical and physiology properties of strains confirmed that the strains are related to the Lactobacillus sp.; further, the 16S rRNA sequencing confirmed 99.99% sequence similarity towards Lactobacillus pla...

  1. methoxyethanol by a new bacterium isolate Pseudomonas sp. Strain

    African Journals Online (AJOL)

    Michael Horsfall

    A 2-methoxyethanol degrading bacterium was isolated from anaerobic sludge of a municipal sewage from ... Stoichiometrically, the strain utilized one mole of oxygen per one mole of 2-methoxyethanol instead of ... physiological and biochemical characterization of the .... observed with acetate and the intact resting cells.

  2. Isolation of strains of Bacillus thuringiensis insecticidal biological activity against Ceratitis capitata

    International Nuclear Information System (INIS)

    Hmaied, Ezzedine; Ben Mbarek, Wael

    2010-01-01

    The present work is to study the effect of toxins (δ-endotoxins) extracted from strains of Bacillus thuringiensis isolated from the mud on the fly Sabkhat Dejoumi Ceratitis capitata, a pest of citrus and fruit trees. Among 51 isolated tested, 15 showed a very significant insecticidal activity, characterized by mortality rates exceeding 80 pour cent. These mortality rates are caused by endotoxins of Bt revealed variability between them. The preliminary results of this study encourage us towards the characterization of the insecticidal activity produced by strains of Bt for large scale application.

  3. Draft Genome Sequences of Three Novel Low-Abundance Species Strains Isolated from Kefir Grain.

    Science.gov (United States)

    Kim, Yongkyu; Blasche, Sonja; Patil, Kiran R

    2017-09-28

    We report here the genome sequences of three novel bacterial species strains- Bacillus kefirresidentii Opo, Rothia kefirresidentii KRP, and Streptococcus kefirresidentii YK-isolated from kefir grains collected in Germany. The draft genomes of these isolates were remarkably dissimilar (average nucleotide identities, 77.80%, 89.01%, and 92.10%, respectively) to those of the previously sequenced strains. Copyright © 2017 Kim et al.

  4. Complete genome sequences of Escherichia coli strains 1303 and ECC-1470 isolated from bovine mastitis

    NARCIS (Netherlands)

    Leimbach, Andreas; Poehlein, Anja; Witten, Anika; Scheutz, Flemming; Schukken, Ynte|info:eu-repo/dai/nl/075051907; Daniel, Rolf; Dobrindt, Ulrich

    2016-01-01

    Escherichia coli is the leading causative agent of acute bovine mastitis. Here, we report the complete genome sequence of E. coli O70:H32 strain 1303, isolated from an acute case of bovine mastitis, and E. coli Ont:Hnt strain ECC-1470, isolated from a persistent infection.

  5. QUANTIFICATION OF SIDEROPHORE AND HEMOLYSIN FROM STACHYBOTRYS CHARTARUM STRAINS, INCLUDING A STRAIN ISOLATED FROM THE LUNG OF A CHILD WITH PULMONARY HEMORRHAGE AND HEMOSIDEROSIS

    Science.gov (United States)

    A strain of Stachybotrys chartarum was recently isolated from the lung of a pulmonary hemorrhage and hemosiderosis (PH) patient in Texas (designated the Houston strain). This is the first time that S. chartarum has been isolated from the lung of a PH patient. In this study, the ...

  6. Synthesis of siderophores by strains of Staphylococcus cohnii isolated from various environments.

    Science.gov (United States)

    Szarapińska-Kwaszewska, Jadwiga; Farkas, Lukasz I

    2003-01-01

    Siderophore activity as the feature of microorganisms enabling colonization of human body and the survival in inanimate environment was investigated in 108 strains of Staphylococcus cohnii; S. cohnii ssp. cohnii (50 strains) and S. cohnii ssp. urealyticus (58 strains). Strains were isolated from people, hospital and non-hospital environment. Highest siderophore activity was noted in strains S. cohnii ssp. urealyticus particularly from the inanimate environments origin. In 86% analyzed strains siderophores of hydroxamate class were detected. Larger amounts of these compounds were synthesized in strains S. cohnii ssp. urealyticus. Strains belonging to both subspecies from human origin showed lower activity of siderophores (total pool) and did not produce hydroxamate class chelators or produced very small amounts of these compounds.

  7. Probiotic attributes of Lactobacillus strains isolated from food and of human origin.

    Science.gov (United States)

    Gaudana, Sandeep B; Dhanani, Akhilesh S; Bagchi, Tamishraha

    2010-06-01

    Lactobacilli isolated from various sources were identified on the basis of 16S-23S rRNA gene intergenic region amplification and subsequent sequencing of the smaller intergenic region. An in vitro analysis of probiotic properties including binding, ability to tolerate different concentrations of bile, survival in acidic buffer and antimicrobial activity of four different isolates and two standard strains (Lactobacillus plantarum American Type Culture Collection (ATCC) 8014 and L. rhamnosus GG (LGG)) was carried out. The ability of each isolate to stimulate Caco-2 cells, human peripheral blood mononuclear cells (PBMC) and THP-1 cells resulting in immunomodulation of these cells was analysed. Isolates L. rhamnosus CS25 and L. delbrueckii M and standard strain ATCC 8014 showed broad antimicrobial activity, and isolates CS25 (percentage of survival 6.9 % at pH 2.5, 5.1 % at pH 2.0) and L. plantarum CS23 (5.7 % at pH 2.5, 4.9 % at pH 2.0) have shown good tolerance to acidic pH. Isolate CS23 showed a good survival (14 %) after 2 h incubation in de Man, Rogosa and Sharpe (MRS) medium containing 3 % bile salts. Isolates CS23, CS25 and L. fermentum ASt1 could stimulate Caco-2 cells, human PBMC and THP-1 cells for a strong and varied immunomodulatory response in these cells. Though LGG showed poor antimicrobial activity as well as bile and acid tolerance, it was found to be the best binding strain tested. Child faecal isolate CS23 from the present study showed high binding ability (seventeen bacteria/Caco-2), high tolerance to acidic pH and bile salts and significant immunomodulation; therefore it is a good potential probiotic candidate.

  8. Pathogenic Strains of Yersinia enterocolitica Isolated from Domestic Dogs (Canis familiaris) Belonging to Farmers Are of the Same Subtype as Pathogenic Y. enterocolitica Strains Isolated from Humans and May Be a Source of Human Infection in Jiangsu Province, China ▿ ‡

    Science.gov (United States)

    Wang, Xin; Cui, Zhigang; Wang, Hua; Tang, Liuying; Yang, Jinchuan; Gu, Ling; Jin, Dong; Luo, Longze; Qiu, Haiyan; Xiao, Yuchun; Xiong, Haiping; Kan, Biao; Xu, Jianguo; Jing, Huaiqi

    2010-01-01

    We isolated 326 Yersinia enterocolitica strains from 5,919 specimens from patients with diarrhea at outpatient clinics, livestock, poultry, wild animals, insect vectors, food, and the environment in the cities of Nantong and Xuzhou in Jiangsu Province, China, from 2004 to 2008. The results showed that the 12 pathogenic strains were of the O:3 serotype. Six strains were isolated from domestic dogs (Canis familiaris) belonging to farmers and were found to be the primary carriers of pathogenic Y. enterocolitica strains, especially in Xuzhou. Pulsed-field gel electrophoresis analysis of the pathogenic strains from dogs belonging to farmers showed that they shared the same patterns as strains from diarrhea patients isolated in 1994. This indicates that the strains from domestic dogs have a close correlation with the strains causing human infections. PMID:20181899

  9. [Phylogenetic analysis of genomes of Vibrio cholerae strains isolated on the territory of Rostov region].

    Science.gov (United States)

    Kuleshov, K V; Markelov, M L; Dedkov, V G; Vodop'ianov, A S; Kermanov, A V; Pisanov, R V; Kruglikov, V D; Mazrukho, A B; Maleev, V V; Shipulin, G A

    2013-01-01

    Determination of origin of 2 Vibrio cholerae strains isolated on the territory of Rostov region by using full genome sequencing data. Toxigenic strain 2011 EL- 301 V. cholerae 01 El Tor Inaba No. 301 (ctxAB+, tcpA+) and nontoxigenic strain V. cholerae O1 Ogawa P- 18785 (ctxAB-, tcpA+) were studied. Sequencing was carried out on the MiSeq platform. Phylogenetic analysis of the genomes obtained was carried out based on comparison of conservative part of the studied and 54 previously sequenced genomes. 2011EL-301 strain genome was presented by 164 contigs with an average coverage of 100, N50 parameter was 132 kb, for strain P- 18785 - 159 contigs with a coverage of69, N50 - 83 kb. The contigs obtained for strain 2011 EL-301 were deposited in DDBJ/EMBL/GenBank databases with access code AJFN02000000, for strain P-18785 - ANHS00000000. 716 protein-coding orthologous genes were detected. Based on phylogenetic analysis strain P- 18785 belongs to PG-1 subgroup (a group of predecessor strains of the 7th pandemic). Strain 2011EL-301 belongs to groups of strains of the 7th pandemic and is included into the cluster with later isolates that are associated with cases of cholera in South Africa and cases of import of cholera to the USA from Pakistan. The data obtained allows to establish phylogenetic connections with V cholerae strains isolated earlier.

  10. Genetic and phenotypic diversity of naturally isolated wild strains of Aspergillus niger with hyper glucose oxidase production

    Directory of Open Access Journals (Sweden)

    MAHMOUD EL-HARIRI

    2015-12-01

    Full Text Available Glucose oxidase (GOx is the basic stone for many of biological industry worldwide. The improvement of GOx production basically depends on selection of hyper producer strain of Aspergillus niger. Selective isolation and screening for natural hyper producer strains of A. niger and sequence analysis of the GOD gene, which is responsible for production of the enzyme, are very effective approaches to investigate the naturally modified strains of A. niger with hyper productive capacity of GOx enzyme. The aims of the current study were selective isolation of naturally hyper GOx producing strains of A. niger and evaluation of their GOx activities under optimized parameters in the laboratory. Five wild Egyptian isolates of A. niger were screened for GOx and catalase activity using two types of modified basal liquid media. The GOx activity was evaluated by high throughout liquid phase system. The isolates showed a variable activity for GOx production ranged from 0 to 28.7 U.ml-1. One isolate coded Strain 7 was negative GOx producer on Vogel's broth medium in comparison to other isolates, while its GOx activity on Cazpek Dox was considered as positive (7.28 U.ml-1. It was concluded that GOx production is affected by three controllable factors – the basal media components, time of incubation, and the strain with its adaption to the media components‎. Also, the catalase activity was tested and it was produced with a different degree of variability, which may be reflected on GOx stability. GOD genes of these wild variant of A. niger were cloned and sequenced to determine intraspecies diversity of GOD between the wild variants. The comparison of isolated wild variants to other reference hyper GOx producer strains of A. niger was performed to determine if the GOD sequence analysis of these strains can be distinguished based on their GOx activity. This is the first report for isolation and detection of naturally A. niger hyper GOx-producer strains with

  11. Selected Lactobacillus strains isolated from sugary and milk kefir reduce Salmonella infection of epithelial cells in vitro.

    Science.gov (United States)

    Zavala, L; Golowczyc, M A; van Hoorde, K; Medrano, M; Huys, G; Vandamme, P; Abraham, A G

    2016-09-01

    The isolation of potentially probiotic strains and the subsequent study of their properties are very important steps to gain insight in the health benefits ascribed to sugary and milk kefir. The aim of the present study was to characterise fifteen Lactobacillus strains isolated from these beverages by determining some surface properties and their ability to antagonise enterocyte cell damage after Salmonella infection in vitro. Lactobacillus surface properties were determined by hydrophobicity, autoaggregation, and coaggregation assays with Salmonella. In addition, lactobacilli adhesion to Caco-2/TC-7 cells and the effect on Salmonella invasion were evaluated. Finally, the disassembly of F-actin cytoskeleton on intestinal epithelial cells was assayed in vitro when Salmonella infection was performed in the presence of selected Lactobacillus strains. Ten out of the 15 strains showed a high adhesion capacity to Caco-2/TC-7 cells. Most of the strains were hydrophilic and non-autoaggregating. Strains isolated from sugary kefir were non-coaggregating with Salmonella, while strains Lactobacillus paracasei CIDCA 83120, 83121, 83123, 83124, 8339, 83102 isolated from milk kefir were able to coaggregate after 1 h. L. paracasei CIDCA 8339 and Lactobacillus kefiri CIDCA 83102 were able to diminish Salmonella invasion to the enterocytes. An antagonistic effect on cytoskeleton disruption elicited by the pathogen was also demonstrated. Our results suggest that both strains isolated from milk kefir could be considered as appropriate probiotic candidates.

  12. Study of Klebsiella pneumoniae strains resistant to carbapenems isolated from blood in eastern Liguria

    Directory of Open Access Journals (Sweden)

    Giulia Carnesecchi

    2012-12-01

    Full Text Available Objectives. Study of multi-resistant Klebsiella pneumoniae strains isolated from blood cultures collected from in-patients of hospitals located in eastern Liguria, and evaluation of the susceptibility to carbapenems and other antibiotics by E-test and automated methods. Methods. At the Laboratory of Clinical Microbiology, of Lavagna Hospital in eastern Liguria, 397 Klebsiella pneumoniae strains were collected from in-patients from different wards of hospitals sites, during the year 2011. They included 115 isolates from blood cultures (aerobic and anaerobic and various biological materials. All strains were tested in the laboratory for their susceptibility to antibiotics. Results. Of the 115 strains of Klebsiella pneumoniae collected from blood cultures 59.1% showed resistance to imipenem, ertapenem, meropenem. Conclusions. The data show a high incidence of resistance to carbapenems in Klebsiella pneumoniae isolated from blood cultures.This is important to implement surveillance programs for control and prevention, but also reduce the intake of antibiotics when they are not strictly necessary.

  13. POTENTIAL PRODUCTION OF CYCLOPIAZONIC ACID BY PENICILLIUM CAMEMBERTI STRAINS ISOLATED FROM CAMEMBERT TYPE CHEESE

    Directory of Open Access Journals (Sweden)

    Miroslava Císarová

    2012-10-01

    Full Text Available The aim of this study was to isolate the strains of fungi from Camembert type cheese, identify them and to test isolated strains of Penicillium camemberti for their ability to produce cyclopiazonic acid. The description of micro- and macromorphological features was used for identification of Penicillium camemberti strains. Strains were subsequently in vitro tested on their potential ability to produce mycotoxin cyclopiazonic acid (CPA. All of the 14 strains of Penicillium camemberti, which were obtained from 20 samples of Camembert type cheese, were cultivated 7, 14, 21, 27 and 30 days on CYA medium at 10±1°C, 15±1°C and 25±1°C in the dark. For determination of CPA production ability by P. camemberti isolates in vitro was TLC used. After 7 days of cultivation cyclopiazonic acid was produced only by 5 from 14 strains cultivated at all cultivation temperatures. After 14 and 21 days of cultivation was CPA produced by 6 strains at all of cultivation temperatures. After 27 and 30 days of cultivation was CPA identified in 7 strains cultivated at all temperatures of cultivation. The other strains also produced mycotoxin, however, not at each temperature. The most productive at all temperatures and after all days were 5 out of 14 tested strains (S9, S10, S13, S18 and S19. Strains S6 and S16 did not produce CPA at any temperature. The lowest production after all days of cultivation was found at 10±1 °C (44% and the highest at 25±1 °C (85%.

  14. Antimicrobial sensitivity and frequency of DRUG resistance among bacterial strains isolated from cancer patients

    International Nuclear Information System (INIS)

    Faiz, M.; Bashir, T.

    2004-01-01

    Blood stream infections (bacteremia) is potentially life threatening. Concomitant with a change in the incidence and epidemiology of infecting organisms, there has been an increase in resistance to many antibiotic compounds. The widespread emergence of resistance among bacterial pathogens has an impact on our ability to treat patients effectively. The changing spectrum of microbial pathogens and widespread emergence of microbial resistance to antibiotic drugs has emphasized the need to monitor the prevalence of resistance in these strains. In the present study frequency of isolation of clinically significant bacteria and their susceptibility and resistance pattern against a wide range of antimicrobial drugs from positive blood cultures collected during 2001-2003 was studied. A total of 102 consecutive isolates were found with 63% gram positive and 44% gram negative strains. The dominating pathogens were Staphylococcus aureus (51%), Streptococci (31%), Pseudomonas (40%), Proteus (13%), Klebsiella (13%). The isolated strains were tested against a wide range of antibiotics belonging to cephalosporins, aminoglycosides and quinolone derivative group by disk diffusion method. It has been observed that isolated strains among gram positive and negative strains showed different level of resistance against aminoglycosides and cephalosporin group of antibiotics with gram positives showing highest number and frequency of resistance against aminoglycosides (40-50%) and cephalosporins.(35-45%) whereas cephalosporins were found to be more effective against gram negatives with low frequency of resistant strains. Cabapenem and quinolone derivative drugs were found to be most effective among other groups in both gram positive and negative strains with 23-41% strains found sensitive to these two drugs. The frequency of sensitive strains against aminoglycoside and cephalosporin in gram negative and gram positive strains were found to be decreasing yearwise with a trend towards an

  15. Controlled fermentation of Moroccan picholine green olives by oleuropein-degrading Lactobacilli strains

    Energy Technology Data Exchange (ETDEWEB)

    Ghabbour, N.; Rokni, Y.; Lamzira, Z.; Thonart, P.; Chihib, N.E.; Peres, C.; Asehraou, A.

    2016-07-01

    The control of the spontaneous fermentation process of un-debittered Moroccan Picholine green olives was undertaken basing the inoculation with two lactobacilli strains (Lactobacillus plantarum S175 and Lactobacillus pentosus S100). These strains, previously selected in our laboratory for their oleuropein-degrading capacity, were inoculated in olives brined at 5% of NaCl, and then incubated at 30 °C. The physico-chemical parameters (pH, free acidity, reducing sugars, sodium chloride, oleuropein and its hydrolysis products), and the microbiological parameters (mesophilic aerobic bacteria, coliforms, Staphylococcus, lactic acid bacteria and yeasts and moulds), were regularly analyzed during the fermentation time. The results obtained showed the effectiveness of the lactic acid bacteria strains to develop suitable oleuropein biodegradation and controlled lactic fermentation processes more than the un-inoculated olives (control). This result was confirmed by the rapid elimination of coliforms and staphylococcus, the accumulation of hydroxytyrosol as a result of oleuropein biodegradation, and a drastic reduction in spoiled olives with good quality fermented olives. (Author)

  16. Characterization of Streptomyces strain SLO-105 isolated from Lake ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-16

    Nov 16, 2009 ... produce a vivid yellow pigment on most media except on the ISP5. The morphological and cultural characteristics of the isolate were compared with known Actinomycetes species described in Bergey's manual of systematic bacteriology and they suggested that SLO-105 strain belong to Streptomyces ...

  17. Isolation of a novel 'atypical' Brucella strain from a bluespotted ribbontail ray (Taeniura lymma).

    Science.gov (United States)

    Eisenberg, Tobias; Riße, Karin; Schauerte, Nicole; Geiger, Christina; Blom, Jochen; Scholz, Holger C

    2017-02-01

    A pleomorphic Gram-negative, motile coccobacillus was isolated from the gills of a wild-caught bluespotted ribbontail ray after its sudden death during quarantine. Strain 141012304 was observed to grow aerobically, to be clearly positive for cytochrome oxidase, catalase, urease and was initially identified as "Brucella melitensis" or "Ochrobactrum anthropi" by Matrix-assisted laser desorption/ionization-time of flight mass spectrometry and VITEK2-compact ® , respectively. Affiliation to the genus Brucella was confirmed by bcsp31 and IS711 PCR as well as by Brucella species-specific multiplex PCR, therein displaying a characteristic banding pattern recently described for Brucella strains obtained from amphibian hosts. Likewise, based on recA sequencing, strain 141012304 was found to form a separate lineage, within the so called 'atypical' Brucella, consisting of genetically more distantly related strains. The closest similarity was detected to brucellae, which have recently been isolated from edible bull frogs. Subsequent next generation genome sequencing and phylogenetic analysis confirmed that the ray strain represents a novel Brucella lineage within the atypical group of Brucella and in vicinity to Brucella inopinata and Brucella strain BO2, both isolated from human patients. This is the first report of a natural Brucella infection in a saltwater fish extending the host range of this medically important genus.

  18. Discrimination and divergence among Lactobacillus plantarum-group (LPG) isolates with reference to their probiotic functionalities from vegetable origin.

    Science.gov (United States)

    Devi, Sundru Manjulata; Aishwarya, Subramanian; Halami, Prakash M

    2016-12-01

    The present study was aimed to evaluate the diversity and probiotic properties of Lactobacillus plantarum-group cultures from vegetable origin. First, genotypic diversity of L. plantarum (n=34) was achieved by PCR of Random Amplified Polymorphic DNA and recA gene-specific multiplex PCR. The isolates were segregated into five groups namely, Lactobacillus pentosus, Lactobacillus paraplantarum, Lactobacillus arizonensis, Lactobacillus plantarum subsp. plantarum and argentoratensis. Further discrimination was achieved by restriction fragment length polymorphism of probiotic adhesion genes viz.fbp, mub and msa gene. As determined by nucleotide sequence analysis and bioinformatics Pfam database, the putative Fbp protein had only one FBP domain, whereas Mub protein had 8-10 MUB domain repeats. However, L. pentosus (except CFR MFT9), L. plantarum subsp. argentoratensis (except CFR MFT5) and L. arizonensis (except CFR MFT2) isolates gave no amplicon for the tested marker genes. Selected cultures (n=15) showed tolerance to simulated digestive fluids (20-85%), exhibited auto-aggregation (10-77%), cellular hydrophobicity (12-78%), and broad spectrum of anti-microbial activity. Concurrently, high adherence capacity to mucin was achieved for L. plantarum subsp. plantarum (MCC 2974 and CFR MFT1) and L. paraplantarum (MTCC 9483, MCC 2977, MCC 2978), which had an additional MUB domain repeat. Copyright © 2016 Elsevier GmbH. All rights reserved.

  19. Phenotypic and molecular identification of Fonsecaea pedrosoi strains isolated from chromoblastomycosis patients in Mexico and Venezuela.

    Science.gov (United States)

    Carolina Rojas, O; León-Cachón, Rafael B R; Pérez-Maya, Antonio Alí; Aguirre-Garza, Marcelino; Moreno-Treviño, María G; González, Gloria M

    2015-05-01

    Chromoblastomycosis is a chronic granulomatous disease caused frequently by fungi of the Fonsecaea genus. The objective of this study was the phenotypic and molecular identification of F. pedrosoi strains isolated from chromoblastomycosis patients in Mexico and Venezuela. Ten strains were included in this study. For phenotypic identification, we used macroscopic and microscopic morphologies, carbohydrate assimilation test, urea hydrolysis, cixcloheximide tolerance, proteolitic activity and the thermotolerance test. The antifungal activity of five drugs was evaluated against the isolates. Molecular identification was performed by sequencing the internal transcribed spacer (ITS) ribosomal DNA regions of the isolated strains. The physiological analysis and morphological features were variable and the precise identification was not possible. All isolates were susceptible to itraconazole, terbinafine, voriconazole and posaconazole. Amphotericin B was the least effective drug. The alignment of the 559-nucleotide ITS sequences from our strains compared with sequences of GenBank revealed high homology with F. pedrosoi (EU285266.1). In this study, all patients were from rural areas, six from Mexico and four from Venezuela. Ten isolates were identified by phenotypic and molecular analysis, using ITS sequence and demonstrated that nine isolates from Mexico and Venezuela were 100% homologous and one isolate showed a small genetic distance. © 2015 Blackwell Verlag GmbH.

  20. Comparative genotyping of Clostridium thermocellum strains isolated from biogas plants: genetic markers and characterization of cellulolytic potential.

    Science.gov (United States)

    Koeck, Daniela E; Zverlov, Vladimir V; Liebl, Wolfgang; Schwarz, Wolfgang H

    2014-07-01

    Clostridium thermocellum is among the most prevalent of known anaerobic cellulolytic bacteria. In this study, genetic and phenotypic variations among C. thermocellum strains isolated from different biogas plants were determined and different genotyping methods were evaluated on these isolates. At least two C. thermocellum strains were isolated independently from each of nine different biogas plants via enrichment on cellulose. Various DNA-based genotyping methods such as ribotyping, RAPD (Random Amplified Polymorphic DNA) and VNTR (Variable Number of Tandem Repeats) were applied to these isolates. One novel approach - the amplification of unknown target sequences between copies of a previously discovered Random Inserted Mobile Element (RIME) - was also tested. The genotyping method with the highest discriminatory power was found to be the amplification of the sequences between the insertion elements, where isolates from each biogas plant yielded a different band pattern. Cellulolytic potentials, optimal growth conditions and substrate spectra of all isolates were characterized to help identify phenotypic variations. Irrespective of the genotyping method used, the isolates from each individual biogas plant always exhibited identical patterns. This is suggestive of a single C. thermocellum strain exhibiting dominance in each biogas plant. The genotypic groups reflect the results of the physiological characterization of the isolates like substrate diversity and cellulase activity. Conversely, strains isolated across a range of biogas plants differed in their genotyping results and physiological properties. Both strains isolated from one biogas plant had the best specific cellulose-degrading properties and might therefore achieve superior substrate utilization yields in biogas fermenters. Copyright © 2014 Elsevier GmbH. All rights reserved.

  1. Genotypic and Phenotypic Characterization of Enterotoxigenic Escherichia coli Strains Isolated from Peruvian Children ▿

    Science.gov (United States)

    Rivera, F. P.; Ochoa, T. J.; Maves, R. C.; Bernal, M.; Medina, A. M.; Meza, R.; Barletta, F.; Mercado, E.; Ecker, L.; Gil, A. I.; Hall, E. R.; Huicho, L.; Lanata, C. F.

    2010-01-01

    Enterotoxigenic Escherichia coli (ETEC) is a major cause of childhood diarrhea. The present study sought to determine the prevalence and distribution of toxin types, colonization factors (CFs), and antimicrobial susceptibility of ETEC strains isolated from Peruvian children. We analyzed ETEC strains isolated from Peruvian children between 2 and 24 months of age in a passive surveillance study. Five E. coli colonies per patient were studied by multiplex real-time PCR to identify ETEC virulence factors. ETEC-associated toxins were confirmed using a GM1-based enzyme-linked immunosorbent assay. Confirmed strains were tested for CFs by dot blot assay using 21 monoclonal antibodies. We analyzed 1,129 samples from children with diarrhea and 744 control children and found ETEC in 5.3% and 4.3%, respectively. ETEC was more frequently isolated from children >12 months of age than from children <12 months of age (P < 0.001). Fifty-two percent of ETEC isolates from children with diarrhea and 72% of isolates from controls were heat-labile enterotoxin (LT) positive and heat-stable enterotoxin (ST) negative; 25% and 19%, respectively, were LT negative and ST positive; and 23% and 9%, respectively, were LT positive and ST positive. CFs were identified in 64% of diarrheal samples and 37% of control samples (P < 0.05). The most common CFs were CS6 (14% and 7%, respectively), CS12 (12% and 4%, respectively), and CS1 (9% and 4%, respectively). ST-producing ETEC strains caused more severe diarrhea than non-ST-producing ETEC strains. The strains were most frequently resistant to ampicillin (71%) and co-trimoxazole (61%). ETEC was thus found to be more prevalent in older infants. LT was the most common toxin type; 64% of strains had an identified CF. These data are relevant in estimating the burden of disease due to ETEC and the potential coverage of children in Peru by investigational vaccines. PMID:20631096

  2. Genome Sequence of Gluconacetobacter sp. Strain SXCC-1, Isolated from Chinese Vinegar Fermentation Starter▿

    OpenAIRE

    Du, Xin-jun; Jia, Shi-ru; Yang, Yue; Wang, Shuo

    2011-01-01

    Gluconacetobacter strains are prominent bacteria during traditional vinegar fermentation. Here, we report a draft genome sequence of Gluconacetobacter sp. strain SXCC-1. This strain was isolated from a fermentation starter (Daqu) used for commercial production of Shanxi vinegar, the best-known vinegar of China.

  3. Draft genome sequences of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from human patients.

    Science.gov (United States)

    Mendoza-Olazarán, Soraya; Garcia-Mazcorro, José F; Morfín-Otero, Rayo; Villarreal-Treviño, Licet; Camacho-Ortiz, Adrián; Rodríguez-Noriega, Eduardo; Bocanegra-Ibarias, Paola; Maldonado-Garza, Héctor J; Dowd, Scot E; Garza-González, Elvira

    2017-01-01

    Herein, we report the draft-genome sequences and annotation of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from humans. One strain (SC-57) was isolated from blood from a male patient in May 2006 and the other (SC-532) from a catheter from a male patient in June 2006. Similar to other genomes of Staphylococcus species, most genes (42%) of both strains are involved in metabolism of amino acids and derivatives, carbohydrates and proteins. Eighty (4%) genes are involved in virulence, disease, and defense and both species show phenotypic low biofilm production and evidence of increased antibiotic resistance associated to biofilm production. From both isolates, a new Staphylococcal Cassette Chromosome mec was detected: mec class A, ccr type 1. This is the first report of whole genome sequences of opportunistic S. cohnii isolated from human patients.

  4. Draft genome sequences of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from human patients

    OpenAIRE

    Mendoza-Olazar?n, Soraya; Garcia-Mazcorro, Jos? F.; Morf?n-Otero, Rayo; Villarreal-Trevi?o, Licet; Camacho-Ortiz, Adri?n; Rodr?guez-Noriega, Eduardo; Bocanegra-Ibarias, Paola; Maldonado-Garza, H?ctor J.; Dowd, Scot E.; Garza-Gonz?lez, Elvira

    2017-01-01

    Herein, we report the draft-genome sequences and annotation of two opportunistic pathogenic strains of Staphylococcus cohnii isolated from humans. One strain (SC-57) was isolated from blood from a male patient in May 2006 and the other (SC-532) from a catheter from a male patient in June 2006. Similar to other genomes of Staphylococcus species, most genes (42%) of both strains are involved in metabolism of amino acids and derivatives, carbohydrates and proteins. Eighty (4%) genes are involved...

  5. [Sensitivity to disinfectants of Candid albicans strains isolated from the hospital environment].

    Science.gov (United States)

    Tadeusiak, B

    1998-01-01

    In recent years an increase of the incidence of Candida infections caused mainly by C. albicans strains especially in high risk inpatients with neoplasms, decreased immunity, burns and after treatment with multiple antibiotics has been observed. Candida organisms are particularly dangerous for newborns being responsible for about 30% of septicaemia cases in newborns in intensive care units. Fungal infections can be endogenous in origin but exogenous infection sources occur in hospitals. The cause of the latter are errors in aseptic management and insufficiently disinfected medical instruments and equipment. The purpose of the study was a comparison of the sensitivity to disinfectants of C. albicans belonging to two laboratory strains C. albicans PZH and C. albicans ATCC 10231 used for the determination of concentrations of two disinfectants used. Besides that, this sensitivity was determined in 14 strains isolated from the patients and one from the circuit of dialysis solution supply to artificial kidney. The study was carried out by the qualitative suspension method, in which the cells in the fluid were subjected to the action of disinfectants, and by the carrier method in which the cells of the microorganisms were present on the surface of metal cylinders. By the suspension method the sensitivity was determined to chloramine T in concentrations from 5.0% to 0.001%, formalin from 10.0% to 0.25%, glutaraldehyde from 2.0% to 0.1%, Septyl from 3.5% to 0.25%. The exposure time was 5, 10, 15, 30 and 60 minutes. The tested strains differed in their sensitivity to the disinfectants used. The greatest interstrain differences were observed in the sensitivity to the disinfectants used. The greatest interstrain differences were observed in the sensitivity to chloramine T. The highest concentrations were tolerated by the strains isolated from the patients and from the artificial kidney circuit as well as by the standard strain ATCC 10231. In the 10-minute exposure time

  6. Genome Sequences of Two Copper-Resistant Escherichia coli Strains Isolated from Copper-Fed Pigs

    DEFF Research Database (Denmark)

    Lüthje, Freja L.; Hasman, Henrik; Aarestrup, Frank Møller

    2014-01-01

    The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances.......The draft genome sequences of two copper-resistant Escherichia coli strains were determined. These had been isolated from copper-fed pigs and contained additional putative operons conferring copper and other metal and metalloid resistances....

  7. Characterization of multiple antibiotic resistant clinical strains of Staphylococcus isolated from pregnant women vagina.

    Science.gov (United States)

    Hetsa, Bakwena Ashton; Kumar, Ajay; Ateba, Collins Njie

    2018-03-29

    Vagina which is one of the important reservoirs for Staphylococcus and in pregnant women pathogenic strains may infect the child during the birth or by vertical transmission. A total of 68 presumptive Staphylococcus strains isolated from human vagina were found to be gram-positive cocci, and only 32 (47%) isolates were found beta-hemolytic. Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) results confirmed 33 isolates belonged to Staphylococcus which consisting of 6 species, i.e., S. aureus (14), S. vitulinus (7), S. epidermidis (4), S cohnii (3), S. equorum (3), and S. succinus (2). Further, the result of antibiotic susceptibility tests showed that large proportions (76%-100%) of the isolates were resistant to multiple antibiotics and more often resistant to penicillin (100%), ampicillin (100%), oxacillin (97%), oxytetracycline (97%), vancomycin (97%), rifampin (85%), erythromycin (82%), and streptomycin (76%). In the present study, only the sec enterotoxin gene was detected in four S. aureus strains. DNA fingerprints of the 33 isolates that were generated using random amplified polymorphic DNA (RAPD) and enterobacterial repetitive intergenic consensus (ERIC) PCR analysis revealed great genetic relatedness of isolates. High prevalence of vaginal colonization with multiple antibiotic-resistant staphylococci among pregnant women was observed which were emerged from the single respective species clones that underwent evolution. The vertical transmission of these multiple antibiotic-resistant Staphylococcus species to the infant is possible; therefore, the findings of this study emphasize the need for regular surveillance of antibiotic-resistant bacterial strains in pregnant women in this area.

  8. Ethanol production potential of local yeast strains isolated from ripe ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-16

    May 16, 2008 ... ... of these studies, the preferred candidate for industrial production of ethanol ... The yeast strains were isolated using the method of Ameh et al. (1989), on ... gas in the Durham tube during the incubation period. Fermentation ...

  9. Assessment of intra-species diversity among strains of Acinetobacter baumannii isolated from sites contaminated with petroleum hydrocarbons

    International Nuclear Information System (INIS)

    Manab Sarma, P.; Bhattacharya, D.; Krishnan, S.; Lal, B.

    2004-01-01

    Intra-species diversity among Acinetobacter baumannii strains isolated from crude oil-contaminated soils from different geographic regions in India was assessed, including their capability to degrade different fractions of total petroleum hydrocarbons. A total of 96 strains were isolated from five different sites. Of the 96 isolates, 25 strains were identified as Acinetobacter baumannii; all of these strains were biochemically profiled and grouped into eight phenovars on the basis of multivariate analysis of their substrate utilization profiles. All strains were able to degrade the total petroleum hydrocarbon fractions of crude oil. Intraspecies relatedness among the 25 strains was determined using tRNA intergenic spacer length polymorphism. Specific variants among the strains with different degradation capacities for different fractions of crude oil were detected. Environmental influences that cause intra-species diversity, such as functional resilience, within the selected strains of A. baumannii were also noted. It is suggested that such diversities may make it possible to select contaminant-specific strains for efficient biotechnological strategies in environmental remediation. 19 refs., 4 tabs., 3 figs

  10. Assessment of intra-species diversity among strains of Acinetobacter baumannii isolated from sites contaminated with petroleum hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Manab Sarma, P.; Bhattacharya, D.; Krishnan, S. [TERI School of Advanced Studies, Center of Bioresources and Biotechnology, New Delhi (India); Lal, B. [TERI School of Advanced Studies, Microbial Biotechnology Division, New Delhi (India)

    2004-06-01

    Intra-species diversity among Acinetobacter baumannii strains isolated from crude oil-contaminated soils from different geographic regions in India was assessed, including their capability to degrade different fractions of total petroleum hydrocarbons. A total of 96 strains were isolated from five different sites. Of the 96 isolates, 25 strains were identified as Acinetobacter baumannii; all of these strains were biochemically profiled and grouped into eight phenovars on the basis of multivariate analysis of their substrate utilization profiles. All strains were able to degrade the total petroleum hydrocarbon fractions of crude oil. Intraspecies relatedness among the 25 strains was determined using tRNA intergenic spacer length polymorphism. Specific variants among the strains with different degradation capacities for different fractions of crude oil were detected. Environmental influences that cause intra-species diversity, such as functional resilience, within the selected strains of A. baumannii were also noted. It is suggested that such diversities may make it possible to select contaminant-specific strains for efficient biotechnological strategies in environmental remediation. 19 refs., 4 tabs., 3 figs.

  11. Cellulose synthesis by Komagataeibacter rhaeticus strain P 1463 isolated from Kombucha.

    Science.gov (United States)

    Semjonovs, Pavels; Ruklisha, Maija; Paegle, Longina; Saka, Madara; Treimane, Rita; Skute, Marite; Rozenberga, Linda; Vikele, Laura; Sabovics, Martins; Cleenwerck, Ilse

    2017-02-01

    Isolate B17 from Kombucha was estimated to be an efficient producer of bacterial cellulose (BC). The isolate was deposited under the number P 1463 and identified as Komagataeibacter rhaeticus by comparing a generated amplified fragment length polymorphism (AFLP™) DNA fingerprint against a reference database. Static cultivation of the K. rhaeticus strain P 1463 in Hestrin and Schramm (HS) medium resulted in 4.40 ± 0.22 g/L BC being produced, corresponding to a BC yield from glucose of 25.30 ± 1.78 %, when the inoculum was made with a modified HS medium containing 10 g/L glucose. Fermentations for 5 days using media containing apple juice with analogous carbon source concentrations resulted in 4.77 ± 0.24 g/L BC being synthesised, corresponding to a yield from the consumed sugars (glucose, fructose and sucrose) of 37.00 ± 2.61 %. The capacity of K. rhaeticus strain P 1463 to synthesise BC was found to be much higher than that of two reference strains for cellulose production, Komagataeibacter xylinus DSM 46604 and Komagataeibacter hansenii DSM 5602 T , and was also considerably higher than that of K. hansenii strain B22, isolated from another Kombucha sample. The BC synthesised by K. rhaeticus strain P 1463 after 40 days of cultivation in HS medium with additional glucose supplemented to the cell culture during cultivation was shown to have a degree of polymerization of 3300.0 ± 122.1 glucose units, a tensile strength of 65.50 ± 3.27 MPa and a length at break of 16.50 ± 0.83 km. For the other strains, these properties did not exceed 25.60 ± 1.28 MPa and 15.20 ± 0.76 km.

  12. Isolation and characterization of a novel native Bacillus thuringiensis strain BRC-HZM2 capable of degrading chlorpyrifos.

    Science.gov (United States)

    Wu, Songqing; Peng, Yan; Huang, Zhangmin; Huang, Zhipeng; Xu, Lei; Ivan, Gelbič; Guan, Xiong; Zhang, Lingling; Zou, Shuangquan

    2015-03-01

    Studies were carried out to isolate chlorpyrifos degrading Bacillus thuringiensis (Bt) strains from chlorpyrifos-contaminated samples. Six Bt strains (isolation rate 2.7%) were isolated by modified sodium acetate antibiotic heat treatment, and one novel strain (BRC-HZM2) was selected for further analysis. Phenotype and phylogeny analysis of this strain was conducted on the basis of biochemical reactions, antibiotic sensitivity, 16s rRNA genes, plasmid profile, insecticidal crystal protein profiles, and PCR-RFLP for cry and cyt genes. The degradation rate of chlorpyrifos in liquid culture was estimated during 48 h of incubation for the isolate BRC-HZM2. More than 50% of the initial chlorpyrifos concentration degraded within 12 h, 88.9% after 48 h. These results highlight the potential of the Bt strain for biological control and the bioremediation of environments contaminated with chlorpyrifos. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Isolation of a nitrate-reducing bacteria strain from oil field brine and ...

    African Journals Online (AJOL)

    A nitrate-reducing bacteria (NRB) strain with vigorous growth, strong nitrate reduction ability, strain B9 2-1, was isolated from Suizhong36-1 oilfield, its routine identification and analysis of 16S rRNA and also the competitive inhibition experiments with the enrichment of sulfate-reducing bacteria (SRB) were carried out.

  14. Pathogenesis and phylogenetic analyses of canine distemper virus strain ZJ7 isolate from domestic dogs in China

    Directory of Open Access Journals (Sweden)

    Tan Bin

    2011-11-01

    Full Text Available Abstract A new isolate of canine distemper virus (CDV, named ZJ7, was isolated from lung tissues of a dog suspected with CDV infection using MDCK cells. The ZJ7 isolate induced cytopathogenic effects of syncytia in MDCK cell after six passages. In order to evaluate pathogenesis of ZJ7 strain, three CDV sero-negative dogs were intranasally inoculated with its virus suspension. All infected dogs developed clinical signs of severe bloody diarrhea, conjunctivitis, ocular discharge, nasal discharge and coughing, fever and weight loss at 21 dpi, whereas the mock group infected with DMEM were normal. The results demonstrated that CDV-ZJ7 strain isolated by MDCK cell was virulent, and the nucleotide and amino acid sequences of strain ZJ7 had no change after isolation by MDCK cell when compared with the original virus from the fresh tissues. Molecular and phylogenetic analyses for the nucleocapsid (N, phosphoprotein (P and receptor binding haemagglutinin (H gene of the ZJ7 isolate clearly showed it is joins to the Asia 1 group cluster of CDV strains, the predominant genotype in China.

  15. Pathogenesis and phylogenetic analyses of canine distemper virus strain ZJ7 isolate from domestic dogs in China.

    Science.gov (United States)

    Tan, Bin; Wen, Yong-Jun; Wang, Feng-Xue; Zhang, Shu-Qin; Wang, Xiu-Dong; Hu, Jia-Xin; Shi, Xin-Chuan; Yang, Bo-Chao; Chen, Li-Zhi; Cheng, Shi-Peng; Wu, Hua

    2011-11-16

    A new isolate of canine distemper virus (CDV), named ZJ7, was isolated from lung tissues of a dog suspected with CDV infection using MDCK cells. The ZJ7 isolate induced cytopathogenic effects of syncytia in MDCK cell after six passages. In order to evaluate pathogenesis of ZJ7 strain, three CDV sero-negative dogs were intranasally inoculated with its virus suspension. All infected dogs developed clinical signs of severe bloody diarrhea, conjunctivitis, ocular discharge, nasal discharge and coughing, fever and weight loss at 21 dpi, whereas the mock group infected with DMEM were normal. The results demonstrated that CDV-ZJ7 strain isolated by MDCK cell was virulent, and the nucleotide and amino acid sequences of strain ZJ7 had no change after isolation by MDCK cell when compared with the original virus from the fresh tissues. Molecular and phylogenetic analyses for the nucleocapsid (N), phosphoprotein (P) and receptor binding haemagglutinin (H) gene of the ZJ7 isolate clearly showed it is joins to the Asia 1 group cluster of CDV strains, the predominant genotype in China.

  16. Functional properties of Lactobacillus plantarum strains isolated from Maasai traditional fermented milk products in Kenya.

    Science.gov (United States)

    Mathara, Julius Maina; Schillinger, Ulrich; Kutima, Phillip M; Mbugua, Samuel K; Guigas, Claudia; Franz, Charles; Holzapfel, Wilhelm H

    2008-04-01

    Lactobacillus plantarum was the major species among the lactic acid bacterial strains isolated from traditional fermented milk of the Maasai in Kenya. Selected strains were characterized for their functional properties using in vitro standard procedures. All strains expressed acid tolerance at pH 2.0 after 2-h exposure of values that ranged from 1% to 100%, while bile tolerance of acid-stressed cells at 0.3% oxgal varied from 30% to 80%. In vitro adhesion to the mucus-secreting cell line HT 29 MTX and binding capacity to extracellular protein matrices was demonstrated for several strains. The four strains tested in a simulated stomach duodenum passage survived with recovery rates ranging from 17% to 100%. Strains were intrinsically resistant to several antibiotics tested. From these in vitro studies, a number of Lb. plantarum strains isolated from the Maasai traditional fermented milk showed probiotic potential. The strains are good candidates for multifunctional starter culture development.

  17. Isolation of soil thermophilic strains of actinomycetes for the ...

    African Journals Online (AJOL)

    use

    2011-12-05

    Dec 5, 2011 ... to high fructose (Pandey et al., 2000; Asgher et al., 2007). *Corresponding ... can be increased by pH, temperature or substrates. ... The following media were used for isolating thermophilic strains of ... To observe the effect of different culture conditions on α-amylase .... Influence of pH on the inactivation of.

  18. Biological characteristics and probiotic effect of Leuconostoc lactis strain isolated from the intestine of black porgy fish

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2013-09-01

    Full Text Available A strain of lactic acid bacteria, Leuconostoc lactis, was isolated from the intestinal tract of black porgy, Sparus macrocephalus, and identified by conventional biochemical characteristics and 16S rDNA gene sequence analysis. The isolated strain had the ability of bile tolerance and resistance to low pH, and survived well in the trypsinase and pepsin solution. But the highly concentrated dose of trypsinase and pepsin affect the viability of the isolated strain. The isolate was resistant to several antibiotics, including Cephalothin, Ceftriaxone, Imipenem and Tobramycin. The isolate could autoaggregate itself and coaggregate with other bacteria in vitro. The autoaggregation percentage increased to 23.29% after 20 h of incubation. The percentage of coaggregation were respectively 31.21%, 29.44%, 10.74%, 16.49%, 24.36%, 24.41% and 20.99% for Vibrio parahaemolyticus, Listeria monocytogenes, Escherichia coli O157, Salmonella typhimurium, Shigella, Staphylococcus aureus and Proteusbacillus vulgaris after 20 h incubation of a mixed suspension. The supernatant of the strain inhibited the growth of several pathogens, such as V.parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Staphylococcus aureus, Escherichia coli O157, Salmonella typhimurium, Bacillus subtilis, Proteusbacillus vulgaris and Shigella. These results indicated that the isolate, Leuconostoc lactis, might be an attractive candidate for perspectival strain for probiotics in marine aquaculture.

  19. Identifikasi Brucella abortus Isolat Lokal dengan Brucella abortus Strain Specific-Polymerase Chain Reaction (IDENTIFICATION OF LOCAL ISOLATES OF BRUCELLA ABORTUS USING BRUCELLA ABORTUS STRAIN SPECIFIC-POLYMERASE CHAIN REACTION ASSAY

    Directory of Open Access Journals (Sweden)

    Susan Maphilindawati Noor

    2014-10-01

    Full Text Available Brucella abortus Strain Specific-Polymerase Chain Reaction (BaSS-PCR is a single multiplex PCRtechnique which able to identify and differentiate between Brucella abortus field strains (biovar 1, 2, and4, B. abortus vaccine strains, Brucella species, and non-Brucella species. In this study, BaSS-PCR wasapplied to identify local isolates of B. abortus in order to investigate the B. abortus strains that infectedcattle in Indonesia. Fifty local strains of B.abortus isolated from infected cattle in Java (Jakarta andBandung, South Sulawesi (Maros, East Nusa Tenggara (Kupang and Belu were used in this study. TheDNA bands were observed by agarose gel in the presence of ethidium bromide. Identification was performedbased on the size and number of DNA products amplified by PCR from each isolates. The results showedthat the 50 isolates were of B. abortus field strains. This finding showed that the cause of bovine brucellosisin Indonesia is B. abortus field strains.

  20. Isolation and characterization of the E. coli membrane protein production strain Mutant56(DE3)

    DEFF Research Database (Denmark)

    Baumgarten, Thomas; Schlegel, Susan; Wagner, Samuel

    2017-01-01

    Membrane protein production is usually toxic to E. coli. However, using genetic screens strains can be isolated in which the toxicity of membrane protein production is reduced, thereby improving production yields. Best known examples are the C41(DE3) and C43(DE3) strains, which are both derived...... from the T7 RNA polymerase (P)-based BL21(DE3) protein production strain. In C41(DE3) and C43(DE3) mutations lowering t7rnap expression levels result in strongly reduced T7 RNAP accumulation levels. As a consequence membrane protein production stress is alleviated in the C41(DE3) and C43(DE3) strains......, thereby increasing membrane protein yields. Here, we isolated Mutant56(DE3) from BL21(DE3) using a genetic screen designed to isolate BL21(DE3)-derived strains with mutations alleviating membrane protein production stress other than the ones in C41(DE3) and C43(DE3). The defining mutation of Mutant56(DE3...

  1. Effect of Antimicrobials on Salmonella Spp. Strains Isolated from Poultry Processing Plants

    Directory of Open Access Journals (Sweden)

    L Mion

    Full Text Available ABSTRACT The routine use of antimicrobials in animal production for the treatment of infections, disease prevention, or as growth promoters is a predisposing factor for the development and dissemination of antimicrobial resistance. In food industries, sanitizers are used for the control of microbial colonization, and their efficacy depends on contact time and on the dilution of the products used. The present study assessed the effect of 12 antimicrobials and four commercial sanitizers on 18 Salmonella spp. strains isolated from poultry processing plants. None of the evaluated antimicrobials was 100% effective against the tested Salmonella spp. strains; however, 94% of the isolates were susceptible to ciprofloxacin, 77% to amoxicillin + clavulanic acid and to ampicillin, and 72% to enrofloxacin, whereas 100% of the isolates were resistant to penicillin G, 16% to tetracycline, and 11% to sulfonamide. The tested Salmonella spp. strains were 100% inhibited by peracetic acid after five minutes of contact, 0.5% by quaternary ammonium after 15 minutes, and 85.7% by chlorhexidine after 15 minutes. The results indicate the importance of testing of efficacy of antimicrobials used in animal production and in public health to monitor their action and the development of resistance.

  2. [Enterotoxin genes occurance among S. aureus strains isolated from inpatients and carriers].

    Science.gov (United States)

    Lawrynowicz-Paciorek, Maja; Kochman, Maria; Piekarska, Katarzyna; Wyrebiak, Agata; Potracka, Ewa; Leniak-Chmiel, Urszula; Magdziak, Agnieszka

    2006-01-01

    We examined 44 inpatients and 66 carriers Staphylococcus aureus strains, isolated in years 2002-2005, for the presence of 18 enterotoxin genes (se/sel) (by PCR), the ability for A-D enterotoxin production (by SET-RPLA) and antibiotic resistance distribution (by disc diffusion method). se/sel genes were detected in 90,9% of all strains, sea (70,5%) and selk and selq (52,3%) - among inpatients strains and egc (65,2%) - among carriers strains were the most frequently se/sel genes found. Positive results of SET-RPLA were consistent with PCR results. There was no correlation observed between antibiotic resistance and se/sel genes distribution among tested S. aureus strains.

  3. Phenotypic and Genotypic Antimicrobial Resistance of Lactococcus Sp. Strains Isolated from Rainbow Trout (Oncorhynchus Mykiss

    Directory of Open Access Journals (Sweden)

    Ture Mustafa

    2015-04-01

    Full Text Available A current profile of antimicrobial resistance and plasmid of 29 Lactococcus garvieae and one Lactococcus lactis strains isolated from rainbow trouts (Oncorhynchus mykiss from farms throughout Turkey were investigated. All isolates were sensitive to penicillin G (90%, ampicillin (86.7%, florfenicol (83.3%, amoxicillin (80.1%, and tetracycline (73.4%, and resistant to trimethoprim+sulfamethoxazole (86.6% and gentamycin (46.6% by disc diffusion method. Twenty-eight (93% isolates had two to seven antibiotic resistance genes (ARGs determined by PCR. The most prevalent ARGs were tetracycline (tetB, erythromycin (ereB, and β-lactam (blaTEM. Bacterial strains were also screened for plasmid DNA by agarose gel electrophoresis and two strains harboured plasmids, with sizes ranging from 3 to 9 kb.

  4. Genome sequence of the pathogenic Herbaspirillum seropedicae strain Os34, isolated from rice roots.

    Science.gov (United States)

    Ye, Weijun; Ye, Shuting; Liu, Jian; Chang, Siping; Chen, Mingyue; Zhu, Bo; Guo, Longbiao; An, Qianli

    2012-12-01

    Most Herbaspirillum seropedicae strains are beneficial endophytes to plants. In contrast, H. seropedicae strain Os34, isolated from rice roots, is pathogenic. The draft genome sequence of strain Os34 presented here allows in-depth comparative genome analyses to understand the specific mechanisms of beneficial and pathogenic Herbaspirillum-plant interactions.

  5. Genome sequence of the pathogenic Herbaspirillum seropedicae strain Os45, isolated from rice roots.

    Science.gov (United States)

    Zhu, Bo; Ye, Shuting; Chang, Siping; Chen, Mingyue; Sun, Li; An, Qianli

    2012-12-01

    Most Herbaspirillum seropedicae strains are beneficial to plants. In contrast, H. seropedicae strain Os45, isolated from rice roots, is pathogenic. The draft genome sequence of strain Os45 presented here allows an in-depth comparative genome analysis to understand the subtle mechanisms of beneficial and pathogenic Herbaspirillum-plant interactions.

  6. Biochemical behavior of Trypanosoma cruzi strains isolated from mice submitted to specific chemotherapy

    Directory of Open Access Journals (Sweden)

    Jesila Pinto M. Marretto

    1994-12-01

    Full Text Available To investigate the influence of chemotherapy on the biochemical beha vior of Trypanosoma cruzi strains, three groups of mice were infected with one of three strains of T. cruzi of different biological and isoenzymic patterns (Peruvian, 21 SF and Colombian strains. Each group was subdivided into subgroups: 1 - treated with nifurtimox; 2 - treated with benznidazole and 3 - untreated infected controls. At the end of treatment, that lasted for 90 days, xenodiagnosis, sub inoculation of blood into new born mice and haemoculture were performed as tests of cure. From the positive tests, 22 samples of T. cruzi were isolated from all subgroups. Electrophoretic analysis of the isoenzymes PGM, GP1, ALAT and AS AT failed to show any difference between parasite strains isolated from treated and untreated mice, which indicates that no detectable clonal selection or parasite genetic markers alterations concerning the isoenzymes analysed have been determined by treatment with drugs of recognized antiparasitic effect, suggesting stability of the phenotypic characteristics of the three biological types of T. cruzi strains.

  7. MICs of Oxazolidinones for Rhodococcus equi Strains Isolated from Humans and Animals

    OpenAIRE

    Bowersock, Terry L.; Salmon, Sarah A.; Portis, Ellen S.; Prescott, John F.; Robison, Denise A.; Ford, Charles W.; Watts, Jeffrey L.

    2000-01-01

    Eperezolid and linezolid are representatives of a new class of orally active, synthetic antimicrobial agents. The in vitro activity values (MICs) of linezolid, eperezolid, and comparator antibiotics against 102 strains of Rhodococcus equi isolated from humans and animals were determined. Linezolid was more active than eperezolid against the strains tested; premafloxacin was the most active comparator antibiotic.

  8. Isolation and characterization of two novel ethanol-tolerant facultative-anaerobic thermophilic bacteria strains from waste compost.

    Science.gov (United States)

    Fong, Jiunn C N; Svenson, Charles J; Nakasugi, Kenlee; Leong, Caine T C; Bowman, John P; Chen, Betty; Glenn, Dianne R; Neilan, Brett A; Rogers, Peter L

    2006-10-01

    In a search for potential ethanologens, waste compost was screened for ethanol-tolerant thermophilic microorganisms. Two thermophilic bacterial strains, M5EXG and M10EXG, with tolerance of 5 and 10% (v/v) ethanol, respectively, were isolated. Both isolates are facultative anaerobic, non-spore forming, non-motile, catalase-positive, oxidase-negative, Gram-negative rods that are capable of utilizing a range of carbon sources including arabinose, galactose, mannose, glucose and xylose and produce low amounts of ethanol, acetate and lactate. Growth of both isolates was observed in fully defined minimal media within the temperature range 50-80 degrees C and pH 6.0-8.0. Phylogenetic analysis of the 16S rDNA sequences revealed that both isolates clustered with members of subgroup 5 of the genus Bacillus. G+C contents and DNA-DNA relatedness of M5EXG and M10EXG revealed that they are strains belonging to Geobacillus thermoglucosidasius. However, physiological and biochemical differences were evident when isolates M5EXG and M10EXG were compared with G. thermoglucosidasius type strain (DSM 2542(T)). The new thermophilic, ethanol-tolerant strains of G. thermoglucosidasius may be candidates for ethanol production at elevated temperatures.

  9. Use of the VNTR typing technique to determine the origin of Mycobacterium tuberculosis strains isolated from Filipino patients in Korea.

    Science.gov (United States)

    Lee, Jihye; Tupasi, Thelma E; Park, Young Kil

    2014-05-01

    With increasing international interchange of personnel, international monitoring is necessary to decrease tuberculosis incidence in the world. This study aims to develop a new tool to determine origin of Mycobacterium tuberculosis strains isolated from Filipino patients living in Korea. Thirty-two variable number tandem repeat (VNTR) loci were used for discrimination of 50 Filipino M. tuberculosis strains isolated in the Philippines, 317 Korean strains isolated in Korea, and 8 Filipino strains isolated in Korea. We found that the VNTR loci 0580, 0960, 2531, 2687, 2996, 0802, 2461, 2163a, 4052, 0424, 1955, 2074, 2347, 2401, 3171, 3690, 2372, 3232, and 4156 had different mode among copy numbers or exclusively distinct copy number in VNTR typing between Filipino and Korean M. tuberculosis strains. When these differences of the VNTR loci were applied to 8 Filipino M. tuberculosis strains isolated in Korea, 6 of them revealed Filipino type while 2 of them had Korean type. Using the differences of mode or repeated number of VNTR loci were very useful in distinguishing the Filipino strain from Korean strain.

  10. Enhanced hydrocarbon biodegradation by a newly isolated bacillus subtilis strain

    International Nuclear Information System (INIS)

    Christova, N.; Tuleva, B.; Nikolova-Damyanova, B.

    2004-01-01

    The relation between hydrocarbon degradation and biosurfactant (rhamnolipid) production by a new bacillus subtilis 22BN strain was investigated. The strain was isolated for its capacity to utilize n-hexadecane and naphthalene and at the same time to produce surface-active compound at high concentrations (1.5 - 2.0 g l -1 ). Biosurfactant production was detected by surface tension lowering and emulsifying activity. The strain is a good degrader of both hydrocarbons used with degradability of 98.3 ± 1% and 75 ± 2% for n-hexadecane and naphthalene, respectively. Measurement of cell hydrophobicity showed that the combination of slightly soluble substrate and rhamnolipid developed higher hydrophobicity correlated with increased utilization of both hydrocarbon substrates. To our knowledge, this is the first report of bacillus subtilis strain that degrades hydrophobic compounds and at the same time produces rhamnolipid biosurfactant. (orig.)

  11. Profile of Shiga toxin-producing Escherichia coli strains isolated from dogs and cats and genetic relationships with isolates from cattle, meat and humans.

    Science.gov (United States)

    Bentancor, A; Rumi, M V; Carbonari, C; Gerhardt, E; Larzábal, M; Vilte, D A; Pistone-Creydt, V; Chinen, I; Ibarra, C; Cataldi, A; Mercado, E C

    2012-05-04

    Pets can be reservoirs of Shiga toxin-producing Escherichia coli (STEC) strains. The aim of this study was to examine nine strains belonging to several serotypes (O91:H21, O91:H16, O178:H19, O8:H19, O22:H8, O22:HNT, ONT:H8), previously recovered from cats or dogs. To this end, we assessed a set of additional virulence genes (stx(2) subtype, subAB, ehxA, eae and saa), cytotoxic activity, and genetic relationships with strains isolated from cattle, meat and humans using pulsed-field gel electrophoresis (PFGE). Most of the isolates carried the stx(2) and/or stx(2vh-b) sequences, while only the O91:H21 isolate presented the mucus-activatable stx(2d) variant, as confirmed by sequencing the genes of subunits A and B. All the strains showed cytotoxic activity in cultured cells. One of the two O178:H19, selected for its high level of cytotoxicity in Vero cells, showed the ability to cause functional alterations in the human colon mucosa in vitro. None of the strains possessed the subAB, eae or saa genes and only the strains belonging to serotype O8:H19 carried the ehxA gene. The isolates shared 90-100% similarity by PFGE to epidemiologically unrelated strains of the corresponding serotypes recovered from cattle, meat or humans. Our results demonstrate that dogs and cats may have a role in the infection of humans by STEC, probably serving as a vehicle for bovine strains in the cycle of human infection, and thus emphasize the health risks for owners and their families. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Isolation of salt stress gene(s) from some haloterant streptomyces strains using polymerase chain reaction (abstract)

    International Nuclear Information System (INIS)

    Mohammad, S.H.

    2005-01-01

    We studied salt tolerance range in sixteen halotolerant streptomyces strains to isolate salt regulated genes using polymerase chain reaction (PCR) technology. A group of these strains was isolated from Sedi-creer (S. niveus Sc-2 and S. sendenensis Sc-II); El-Malahat (Alexndria) (S. graminofaciens Ma-13): Qaroon's lake (S. albovinaceus QA-44, S. luteofluorescens Qa-51, S. albidoflavous Qa-53 and S. erthaeus QA-84). The other group represents the strains isolated from different soils from Damaaita (S. violans Da-3). Ismailia (S. alboflavus-Is-10). Port said (S. bobili Ps-12) and Sinai sandy soil (streptomyces species Si-1, S. truirus Si-4, S. lateritius Si-6, S. hawaiiensis Si-8, S. muavecolor Si-9 and S. melanogenes Si-11). These strains were varied in their salt tolerance range in particular, with increasing NaCl concentration in the growth medium up to 14%. It was also noted that all the applied Streptomyces strains appeared abundant growth at NaCl concentrations of 0.05, 3.5 and 7.0%. When NaCl was added at concentration of 10.5%, all of them except S. melanogenes Si-II strain gave moderate growth. On the contrary, NaCl at concentration of 14% inhibited the growth of 50% of strains under investigation. But the other 50% of these strains gave moderate growth at the same NaCl concentration. At the molecular level, the PCR was successfully used for isolating the mtlD and P5CS genes from 3 (S. alboinaceus Qa-44, S. albidoflavus Qa-53, S. erthraeus QA-84) and 4 (S. albovunaecaus Qa-44, Streptomyces species Si-I, S. luteofluorescens Qa-51, S. latritius Si-6) strains, respectively. As PCR fragments with a size of about 1095 and 2100 bp were amplified from the DNA genome of these strains using the primer pairs (P1 and P2) and (P3 and P4), respectively. These results confirmed the ability to use PCR for isolation or detection of any gene based on its nucleotide sequencing in any microorganism. Furthermore, one can recommended the use of the applied halotolerant

  13. Bioremediation potential of a newly isolate solvent tolerant strain Bacillus thermophilus PS11

    Directory of Open Access Journals (Sweden)

    PAYEL SARKAR

    2012-01-01

    Full Text Available The increased generation of solvent waste has been stated as one of the most critical environmental problems. Though microbial bioremediation has been widely used for waste treatment but their application in solvent waste treatment is limited since the solvents have toxic effects on the microbial cells. A solvent tolerant strain of Bacillus thermophilus PS11 was isolated from soil by cyclohexane enrichment. Transmission electron micrograph of PS11 showed convoluted cell membrane and accumulation of solvents in the cytoplasm, indicating the adaptation of the bacterial strain to the solvent after 48h of incubation. The strain was also capable of growing in presence of wide range of other hydrophobic solvents with log P-values below 3.5. The isolate could uptake 50 ng/ml of uranium in its initial 12h of growth, exhibiting both solvent tolerance and metal resistance property. This combination of solvent tolerance and metal resistance will make the isolated Bacillus thermophilus PS11 a potential tool for metal bioremediation in solvent rich wastewaters.

  14. Molecular detection and antimicrobial resistance of diarrheagenic Escherichia coli strains isolated from diarrheal cases

    International Nuclear Information System (INIS)

    Aslani, Mehdi M.; Salmanzadeh-Ahrabi, S.; Jafari, F.; Zali, Reza M.; Mani, M.; Alikhani, Yousef M.

    2008-01-01

    Objective was to identify and classify Iranian isolates of diarrheagenic Escherichia coli (E. coli) on the basis of presence of virulence genes and to determine antibiotic susceptibility of isolated strains. The current cross-sectional study was conducted in 2005 at the Pasteur Institute, Tehran, Iran. One hundred and ninety-three diarrheagenic E. coli isolated from diarrheal patients in different regions of Iran were included in current study. Virulence factors genees for diarrheagenic E. coli were detected by polymerase chain reaction. Of the 193 diarrheagenic E. coli detected by PCR, 86(44.5%) were Shiga toxin-producing E. coli (STEC), 74 (38.4%) enteropathogenic E. coli (EPEC), 19 (9.8%) enteroaggregative E. coli and 14 (7.3%) enterotoxigenic E. coli isolates. Susceptibility to 12 clinically important antimicrobial agents was determined for 193 strains of diarrhheagenic E. coli. A high incidence of resistance to tetracycline (63%), ampicillin (62%), streptomycin (56%), amoxicillin/clavulanic acid (44.5%), trimetoprim/sulphamethoxazole (39.5%) and cephalothin (37%) was observed. The STEC and EPEC strains with high resistance to tetracycline and ampicillin but highly susceptible to quinolones are among the most important causative agent of diarrhea in Iran. This study suggests that antimicrobial resistance is wide spread among E. coli strains colonizing Iranian patients. Guidelines for appropriate use of antibiotics in developing countries require updating. (author)

  15. Identification of a DNA restriction-modification system in Pectobacterium carotovorum strains isolated from Poland.

    Science.gov (United States)

    Waleron, K; Waleron, M; Osipiuk, J; Podhajska, A J; Lojkowska, E

    2006-02-01

    Polish isolates of pectinolytic bacteria from the species Pectobacterium carotovorum were screened for the presence of a DNA restriction-modification (R-M) system. Eighty-nine strains of P. carotovorum were isolated from infected potato plants. Sixty-six strains belonged to P. carotovorum ssp. atrosepticum and 23 to P. carotovorum ssp. carotovorum. The presence of restriction enzyme Pca17AI, which is an isoschizomer of EcoRII endonuclease, was observed in all isolates of P. c. atrosepticum but not in P. c. carotovorum. The biochemical properties, PCR amplification, and sequences of the Pca17AI restriction endonuclease and methyltransferase genes were compared with the prototype EcoRII R-M system genes. Only when DNA isolated from cells of P. c. atrosepticum was used as a template, amplification of a 680 bp homologous to the gene coding EcoRII endonuclease. Endonuclease Pca17AI, having a relatively low temperature optimum, was identified. PCR amplification revealed that the nucleotide sequence of genes for EcoRII and Pca17AI R-M are different. Dcm methylation was observed in all strains of Pectobacterium and other Erwinia species tested. The sequence of a DNA fragment coding Dcm methylase in P. carotovorum was different from that of Escherichia coli. Pca17AI is the first psychrophilic isoschizomer of EcoRII endonuclease. The presence of specific Dcm methylation in chromosomal DNA isolated from P. carotovorum is described for the first time. A 680 bp PCR product, unique for P. c. atrosepticum strains, could serve as a molecular marker for detection of these bacteria in environmental samples.

  16. Resistance to Antibiotics in Strains of Staphylococcus spp., Enterococcus spp. and Escherichia coli Isolated from Rectal Swabs of Pigs

    Directory of Open Access Journals (Sweden)

    M. Kolář

    2008-01-01

    Full Text Available The study aimed at determining the level of resistance of selected bacterial species (Staphylococcus spp., Enterococcus spp., Escherichia coli isolated from rectal swabs of pigs to antimicrobial agents. The tested strains were isolated from piglets aged 7 to 30 days. Bacterial species were identified by standard microbiological techniques and susceptibility to antibiotics was determined quantitatively by the standard microdilution method. Resistance of the Staphylococcus aureus strain to oxacillin was confirmed by detection of the mecA gene and PBP2a. A total of 115 Staphylococcus spp. isolates were collected. In the case of Staphylococcus aureus, the methicillin-resistant strain (MRSA was identified. Moreover, higher frequency of coagulase-negative staphylococci with minimum inhibitory concentration of oxacillin ≥ 0.5 mg/l was noticed. Inducible resistance to clindamycin in the Staphylococcus hominis strain was also detected. The strains of Enterococcus spp. (61 isolates exhibited high resistance to tetracycline (98.5%, erythromycin (86.8% and chloramphenicol (54.4%. Vancomycin-resistant enterococci were not isolated. In the case of Escherichia coli strains (111 isolates, higher frequency of resistant strains to tetracycline (81.1% and ampicillin (62.2% was documented. Resistance to fluoroquinolones and production of broad-spectrum β-lactamases was not noticed. The presented study may be considered as a pilot project assessing the prevalence of resistant bacteria in piglets kept on a single farm. It demonstrated the presence of resistant strains of Staphylococcus spp., including one MRSA strain, Enterococcus spp. and Escherichia coli. These strains may be present as a result of postnatal colonization with both bacterial microflora of dams and environmental microflora.

  17. Evaluation of pathogenesis caused in cattle and guinea pig by a Mycobacterium bovis strain isolated from wild boar

    Directory of Open Access Journals (Sweden)

    Di Rienzo Julio

    2011-07-01

    Full Text Available Abstract Background In many regions of the world, wild mammals act as reservoir of Mycobacterium bovis, a situation that prevents the eradication of bovine tuberculosis. In order to observe whether a strain isolated from a wild boar, previously tested as highly virulent in a mice model, is also virulent in cattle, we performed cattle experimental inoculation with this strain Results Groups of Friesian calves were either infected with the wild boar strain M. bovis 04-303 or with the bovine strain NCTC10772 as a control. We found that antigen-specific IFN-γ release in whole blood samples occurred earlier in animals infected with M. bovis 04-303. Both M. bovis strains resulted in a positive skin test, with animals infected with the wild boar isolate showing a stronger response. These results and the presence of more severe organ lesions, with granuloma and pneumonic areas in cattle demonstrate that the wild boar isolate is more virulent than the NCTC10772 strain. Additionally, we tested the infectivity of the M. bovis strains in guinea pigs and found that M. bovis 04-303 had the highest pathogenicity. Conclusions M. bovis strains isolated from wild boars may be pathogenic for cattle, producing TB lesions.

  18. Identifikasi Brucella abortus Isolat Lokal dengan Brucella abortus Strain Specific-Polymerase Chain Reaction (IDENTIFICATION OF LOCAL ISOLATES OF BRUCELLA ABORTUS USING BRUCELLA ABORTUS STRAIN SPECIFIC-POLYMERASE CHAIN REACTION ASSAY)

    OpenAIRE

    Susan Maphilindawati Noor; Pratiwi Pujilestari Sudarmono; Asmarani Kusumawati; Anis Karuniawati

    2014-01-01

    Brucella abortus Strain Specific-Polymerase Chain Reaction (BaSS-PCR) is a single multiplex PCRtechnique which able to identify and differentiate between Brucella abortus field strains (biovar 1, 2, and4), B. abortus vaccine strains, Brucella species, and non-Brucella species. In this study, BaSS-PCR wasapplied to identify local isolates of B. abortus in order to investigate the B. abortus strains that infectedcattle in Indonesia. Fifty local strains of B.abortus isolated from infected cattle...

  19. Genome Sequence Analysis of New Isolates of the Winona Strain of Plum pox virus and the First Definitive Evidence of Intrastrain Recombination Events.

    Science.gov (United States)

    James, Delano; Sanderson, Dan; Varga, Aniko; Sheveleva, Anna; Chirkov, Sergei

    2016-04-01

    Plum pox virus (PPV) is genetically diverse with nine different strains identified. Mutations, indel events, and interstrain recombination events are known to contribute to the genetic diversity of PPV. This is the first report of intrastrain recombination events that contribute to PPV's genetic diversity. Fourteen isolates of the PPV strain Winona (W) were analyzed including nine new strain W isolates sequenced completely in this study. Isolates of other strains of PPV with more than one isolate with the complete genome sequence available in GenBank were included also in this study for comparison and analysis. Five intrastrain recombination events were detected among the PPV W isolates, one among PPV C strain isolates, and one among PPV M strain isolates. Four (29%) of the PPV W isolates analyzed are recombinants; one of which (P2-1) is a mosaic, with three recombination events identified. A new interstrain recombinant event was identified between a strain M isolate and a strain Rec isolate, a known recombinant. In silico recombination studies and pairwise distance analyses of PPV strain D isolates indicate that a threshold of genetic diversity exists for the detectability of recombination events, in the range of approximately 0.78×10(-2) to 1.33×10(-2) mean pairwise distance. RDP4 analyses indicate that in the case of PPV Rec isolates there may be a recombinant breakpoint distinct from the obvious transition point of strain sequences. Evidence was obtained that indicates that the frequency of PPV recombination is underestimated, which may be true for other RNA viruses where low genetic diversity exists.

  20. Characterization of field isolates of Suid herpesvirus 1 (Aujeszky's disease virus) as derivatives of attenuated vaccine strains

    DEFF Research Database (Denmark)

    Christensen, Laurids Siig; Medveczky, I.; Strandbygaard, Bertel

    1992-01-01

    Field isolates of suid herpesvirus 1 (Aujeszky's disease virus) from Poland and Hungary were identified by restriction fragment pattern analysis as derivatives of attenuated vaccine strains. The Polish isolates were found to be related to the BUK-TK-900 strain (Suivac A) which is widely used...

  1. [Isolation, identification and characterization of acid-producing strains from psychrotolerant biogas fermentation].

    Science.gov (United States)

    Wan, Yongqing; Zhang, Wei; Mandlaa; Tian, Ruihua; Wang, Ruigang; Duan, Kaihong

    2015-11-04

    The aim of this study was to screen acid-producing strains from the broth of psychrotolerant biogas fermentation and evaluate the acid-producing character of them. Acid-producing strains were isolated by a medium with methyl red at 4 degrees C in Petri dishes and identified by morphology observation and 16S rRNA sequencing. Moreover, the ability of hydrolysis of starch, fermentation of carbohydrates, liquefaction of gelatin and production of catalase were studied. Two acid-producing strains (FJ-8 and FJ-15) were isolated. The result of the 16S rRNA phylogenetic tree shows that FJ-8 and FJ-15 belong to Pseudomonas sp. and Shewanella sp., respectively. Both FJ-8 and FJ-15 could hydrolyze starch, liquidize gelatin and produce catalase. The optimum temperature for acid-producing of FJ-8 and FJ-15 is 15 degrees C and 20 degrees C, respectively. After 10 days cultivation at 4 degrees C, the concentration of acetic acid was 792 mg/L and 966 mg/L of FJ-8 and FJ-15, respectively. The selected strains, FJ-8 and FJ-15, have the potential to produce acids at low temperature.

  2. Indigenous strains of Lactobacillus isolated from the Istrian cheese as potential starter cultures

    Directory of Open Access Journals (Sweden)

    Nataša Hulak

    2016-11-01

    Full Text Available Istrian ewe’s milk cheese is an autochthonous product that is manufactured for generations on small family farms in the Croatian peninsula Istria. Traditional Istrian cheese is made from unpasteurized ewe’s milk, without the addition of starter cultures. Consequently, the specific flavour and texture of the Istrian cheese is owed to metabolic processes of indigenous microflora of which Lactobacillus species play pivotal role. Characterisation and selection of indigenous lactobacilli may result in the potential use of selected strains as starter, bioprotective or even probiotic cultures. This study focuses on potential use of Lactobacillus plantarum and Lactobacillus casei isolated from traditional Istrian cheese as starter cultures, by using methods that determine their proteolytic, lipolytic, antimicrobial and haemolytic potential, as well as their ability of acidification, autoaggregation and survival in simulated gastrointestinal conditions. Our results indicated that from 12 representative strains most revealed a low or moderate proteolytic activity as well as absence of lipolytic and haemolytic activities. From 12 strains, 5 of them showed a medium to strong acidification ability and lowered the pH of milk below 5.00 after 24 hours of incubation. Furthermore, almost all isolates exhibited antimicrobial activity against Serratia marcescens, and lowest number of isolates showed antimicrobial activity against Staphylococcus aureus and Listeria innocua. The studied Lactobacillus strains revealed high survival rate in a simulated oral cavity and duodenum conditions, while the survival ability in a simulated gastric conditions was much lower. Ability to aggregate was low for all tested strains, after 3 hours and after 5 hours of incubation.

  3. Efficient screening of environmental isolates for Saccharomyces cerevisiae strains that are suitable for brewing.

    Science.gov (United States)

    Fujihara, Hidehiko; Hino, Mika; Takashita, Hideharu; Kajiwara, Yasuhiro; Okamoto, Keiko; Furukawa, Kensuke

    2014-01-01

    We developed an efficient screening method for Saccharomyces cerevisiae strains from environmental isolates. MultiPlex PCR was performed targeting four brewing S. cerevisiae genes (SSU1, AWA1, BIO6, and FLO1). At least three genes among the four were amplified from all S. cerevisiae strains. The use of this method allowed us to successfully obtain S. cerevisiae strains.

  4. Virulence Genes and Antimicrobial Resistance Profiles of Pasteurella multocida Strains Isolated from Rabbits in Brazil

    Directory of Open Access Journals (Sweden)

    Thais Sebastiana Porfida Ferreira

    2012-01-01

    Full Text Available Pasteurella multocida is responsible for a wide range of diseases in domestic animals. In rabbits, the agent is related to nasal discharge, pneumonia, otitis media, pyometra, orchitis, abscess, and septicemia. One hundred and forty rabbits with respiratory diseases from four rabbitries in São Paulo State, Brazil were evaluated for the detection of P. multocida in their nasal cavities. A total of twenty-nine animals were positive to P. multocida isolation, and 46 strains were selected and characterized by means of biochemical tests and PCR. P. multocida strains were tested for capsular type, virulence genes, and resistance profile. A total of 45.6% (21/46 of isolates belonged to capsular type A, and 54.34% (25/46 of the isolates were untypeable. None of the strains harboured toxA or pfhA genes. The frequency of the other twenty genes tested was variable, and the data generated was used to build a dendrogram, showing the relatedness of strains, which were clustered according to origin. Resistance revealed to be more common against sulfonamides and cotrimoxazole, followed by erythromycin, penicillin, and amoxicillin.

  5. Susceptibility of clinical isolates of Bacteroides fragilis group strains to cefoxitin, cefoperazone and ticarcillin/clavulanate

    Directory of Open Access Journals (Sweden)

    PEIXOTO JÚNIOR Arnaldo Aires

    2000-01-01

    Full Text Available A total of 40 strains of the B. fragilis group was isolated from clinical specimens in two hospital centers in Fortaleza from 1993 to 1997. The most frequently isolated species was Bacteroides fragilis (19 strains and most isolates came from intra-abdominal and wound infections. The susceptibility profile was traced for cefoxitin, cefoperazone and ticarcillin-clavulanate by using the agar dilution reference method. All isolates were susceptible to ticarcillin-clavulanate (128/2mug/ml. Resistance rates of 15 and 70% were detected to cefoxitin (64mug/ml and cefoperazone (64mug/ml, respectively. Such regional results permit a better orientation in choosing this group of antibiotics for prophylaxis and therapy especially in relation to cefoxitin, which is frequently used in the hospital centers studied.

  6. Isolation and determination antimicrobial susceptibility pattern of Enterobacter cloacae strains isolated from consumed powdered infant formula milk in NICU ward

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    Jalal Mardaneh

    2014-11-01

    Full Text Available Background: Enterobacter cloacae is a rod-shaped, gram-negative bacillus, from the family of Enterobacteriaceae. It is an opportunistic pathogen and causes disease in plants and humans (premature and immunocompromised persons of all age groups. The goal of this study was to isolate and determine antimicrobial susceptibility pattern of Enterobacter cloacae strains isolated from consumed powdered infant formula (PIF milk in Neonatal Intensive Care Unit (NICU ward. Material and Methods: In this cross-sectional study, a total of 125 consumed powdered infant formula milk in NICU ward were surveyed. Isolation and Identification of microorganisms was carried out according to FDA method. Antimicrobial susceptibility test was performed using the standard disc diffusion method based on CLSI (2011 recommendations. Results: Enterobacter cloacae was isolated from 2 (1.6% of 125 PIF milk samples. The results showed that isolated strains are sensitive to most antibiotics. All isolates were resistant to amoxicillin. Conclusion: Since the infant formula (PIF samples are unsterile products and contamination could occure during different steps, it is imperative to prepare the infant formula milk foods according to the manufacturer’s instruction and in an aseptic condition. Contamination of PIF only could be reduced or prevented by monitoring the critical control points and taking appropriate action during the processing.

  7. Biodegradation of Chlorpyrifos by Pseudomonas Resinovarans Strain AST2.2 Isolated from Enriched Cultures.

    OpenAIRE

    Anish Sharma*,; Jyotsana Pandit; Ruchika Sharma and; Poonam Shirkot

    2016-01-01

    A bacterial strain AST2.2 with chlorpyrifos degrading ability was isolated by enrichment technique from apple orchard soil with previous history of chlorpyrifos use. Based on the morphological, biochemical tests and 16S rRNA sequence analysis, AST2.2 strain was identified as Pseudomonas resinovarans. The strain AST2.2 utilized chlorpyrifos as the sole source of carbon and energy. This strain exhibited growth upto 400mg/l concentration of chlorpyrifos and exhibited high extracellular organopho...

  8. Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters

    Directory of Open Access Journals (Sweden)

    Renata Albuquerque Costa

    Full Text Available The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains (n = 70 isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL, caseinase (CAS, elastase (ELAS, phospholipase (PHOS, lipase (LIP, amilase (AML and DNase. All enzymes, except elastase, were detected in more than 60% of the strains. The most recurrent enzymatic profiles were AML + DNase + PHOS + GEL + LIP (n = 16; 22.9% and AML + CAS + DNase + PHOS + GEL + LIP (n = 21; 30%. Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters.

  9. The prevalence of virulence genes of E. coli strains isolated from children with urinary tract infection

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    Farshad Shohreh

    2009-01-01

    Full Text Available To evaluate the prevalence of virulence genes in E. coli strains isolated from urine samples of children with urinary tract infection(UTI and their correlation with clinical data, we iso-lated E. coli strains from urine samples of children with UTI during the period of August 2005 - August 2006 and studied them for the presence of the virulence genes by PCR. A total of 96 E. coli strains were isolated. The prevalence of genes, pyelonephritis associated pili (pap genes, S-family adhesions (sfa gene, hemolysin (hly gene, and cytotoxic nercotizing factor type 1 (cnf-1-1 gene among the isolated strains was 27.1%, 14.6%, 13.5% and 22.9 %, respectively. Pyelonephritis was more prevalent in the cases with positive virulence genes. The results showed significant correlation bet-ween age of the patient and the presence of the genes (P< 0.05. Cnf-1 gene was significantly more common in samples of patients with abnormal finding on the ultrasound of kidneys (P= 0.049. Our study demonstrated higher prevalence of pyelonephritis in the presence of E. coli virulence genes. Detection of the genes in urine samples may help in the management of UTI.

  10. The prevalence of virulence genes of E. coli strains isolated from children with urinary tract infection

    International Nuclear Information System (INIS)

    Farshad, Shohreh; Emamghorashi, Fatemeh

    2009-01-01

    To evaluate the prevalence of virulence genes in E. coli strains isolated from urine samples of children with urinary tract infection(UTI) and their correlation with clinical data, we isolated E. coli strains from urine samples of children with UTI during the period of August 2005 - August 2006 and studied them for the presence of the virulence genes by PCR. A total of 96 E. coli strains were isolated. The prevalence of genes, pyelonephritis associated pili (pap genes), S-family adhesions (sfa gene), hemolysin (hly gene), and cytotoxic nercotizing factor type 1 (cnf-1-1 gene) among the isolated strains was 27.1%, 14.6%, 13.5% and 22.9 %, respectively. Pyelonephritis was more prevalent in the cases with positive virulence genes. The results showed significant correlation between age of the patient and the presence of the genes (P< 0.05). Cnf-1 gene was significantly more common in samples of patients with abnormal finding on the ultrasound of kidneys (P0.049). Our study demonstrated higher prevalence of pyelonephritis in the presence of E. coli virulence genes. Detection of the genes in urine samples may help in the management of UTI. (author)

  11. Sequence-based comparative study of classical swine fever virus genogroup 2.2 isolate with pestivirus reference strains.

    Science.gov (United States)

    Kumar, Ravi; Rajak, Kaushal Kishor; Chandra, Tribhuwan; Muthuchelvan, Dhanavelu; Saxena, Arpit; Chaudhary, Dheeraj; Kumar, Ajay; Pandey, Awadh Bihari

    2015-09-01

    This study was undertaken with the aim to compare and establish the genetic relatedness between classical swine fever virus (CSFV) genogroup 2.2 isolate and pestivirus reference strains. The available complete genome sequences of CSFV/IND/UK/LAL-290 strain and other pestivirus reference strains were retrieved from GenBank. The complete genome sequence, complete open reading frame, 5' and 3' non-coding region (NCR) sequences were analyzed and compared with reference pestiviruses strains. Clustal W model in MegAlign program of Lasergene 6.0 software was used for analysis of genetic heterogeneity. Phylogenetic analysis was carried out using MEGA 6.06 software package. The complete genome sequence alignment of CSFV/IND/UK/LAL-290 isolate and reference pestivirus strains showed 58.9-72% identities at the nucleotide level and 50.3-76.9% at amino acid level. Sequence homology of 5' and 3' NCRs was found to be 64.1-82.3% and 22.9-71.4%, respectively. In phylogenetic analysis, overall tree topology was found similar irrespective of sequences used in this study; however, whole genome phylogeny of pestivirus formed two main clusters, which further distinguished into the monophyletic clade of each pestivirus species. CSFV/IND/UK/LAL-290 isolate placed with the CSFV Eystrup strain in the same clade with close proximity to border disease virus and Aydin strains. CSFV/IND/UK/LAL-290 exhibited the analogous genomic organization to those of all reference pestivirus strains. Based on sequence identity and phylogenetic analysis, the isolate showed close homology to Aydin/04-TR virus and distantly related to Bungowannah virus.

  12. Comparison of Antibacterial Activity of Lactobacillus plantarum Strains Isolated from Two Different Kinds of Regional Cheeses from Poland: Oscypek and Korycinski Cheese

    Directory of Open Access Journals (Sweden)

    Aleksandra Ołdak

    2017-01-01

    Full Text Available Oscypek and korycinski are traditional Polish cheeses, exclusively produced in Tatra and in Podlasie region, respectively, produced from raw, unpasteurized milk. The 29 Lactobacillus plantarum strains were isolated on MRS agar from 12 cheese samples and used as a material for study. The main purpose of the work was to assess the antimicrobial properties and recognition of selected strains for the unique antagonistic activity and preservation role in food. It has been found that the highest antimicrobial activity was observed in the case of L. monocytogenes strains; however, the level of that activity was different depending on the Lb. plantarum strain. Strains from oscypek produced broad spectrum, and a few strains isolated from korycinski cheese produced a narrow spectrum of antimicrobial compounds, other than organic acids and hydrogen peroxide. Moreover, the antagonistic activity shown by Lb. plantarum strains is connected with the source from which a given strain was isolated. Strains isolated from oscypek cheese represented stronger activity against L. monocytogenes, whereas strains isolated from korycinski cheese were more active against E. coli. Strains Lb. plantarum Os13 and Kor14 could be considered as good candidates for protective cultures to extend durability of food products.

  13. Comparison of Antibacterial Activity of Lactobacillus plantarum Strains Isolated from Two Different Kinds of Regional Cheeses from Poland: Oscypek and Korycinski Cheese

    Science.gov (United States)

    Ołdak, Aleksandra; Rzepkowska, Anna

    2017-01-01

    Oscypek and korycinski are traditional Polish cheeses, exclusively produced in Tatra and in Podlasie region, respectively, produced from raw, unpasteurized milk. The 29 Lactobacillus plantarum strains were isolated on MRS agar from 12 cheese samples and used as a material for study. The main purpose of the work was to assess the antimicrobial properties and recognition of selected strains for the unique antagonistic activity and preservation role in food. It has been found that the highest antimicrobial activity was observed in the case of L. monocytogenes strains; however, the level of that activity was different depending on the Lb. plantarum strain. Strains from oscypek produced broad spectrum, and a few strains isolated from korycinski cheese produced a narrow spectrum of antimicrobial compounds, other than organic acids and hydrogen peroxide. Moreover, the antagonistic activity shown by Lb. plantarum strains is connected with the source from which a given strain was isolated. Strains isolated from oscypek cheese represented stronger activity against L. monocytogenes, whereas strains isolated from korycinski cheese were more active against E. coli. Strains Lb. plantarum Os13 and Kor14 could be considered as good candidates for protective cultures to extend durability of food products. PMID:28626762

  14. Ultrastructural and chemotaxonomic analysis of a xylanolytic strain of Cryptococcus adeliensis isolated from sheep droppings in Spain.

    Science.gov (United States)

    Velázquez, Encarna; del Villar, María; Grondona, Isabel; Monte, Enrique; González-Villa, Tomás

    2006-09-01

    Cryptococcus adeliensis was initially described as a psycrophilic species containing a single strain CBS 8351(T) isolated from decayed algae in Terre Adelie (Antartida). Later, a second strain of this species was isolated from an immunosuppressed patient affected by leukaemia in Germany and recently several strains from this species have been found in human patients and pigeon droppings of the same country. In this study, we isolated from sheep droppings in Spain a xylanolytic strain named LEVX01 that was phenotypically related to the strain CBS 8351(T) and showed a 100% similarity in the D1/D2 domain and 5.8S-ITS region sequences with respect to the remaining described strains of C. adeliensis. These findings suggest that this species has a wide geographical distribution and that the animal faeces are a common habitat for C. adeliensis. The chemotaxonomic analyses showed the absence of detectable amounts of xylose in the cell walls of the strains LEVX01 and CBS8351(T) in contrast to other Cryptococcus species. Interestingly, the ultrastructural study showed the presence of fimbriae in these two strains that could be involved in the attachment to the host cells and, as occurs in Candida albicans, they could also be a pathogenicity factor for the man.

  15. Clonality and Resistome analysis of KPC-producing Klebsiella pneumoniae strain isolated in Korea using whole genome sequencing.

    Science.gov (United States)

    Lee, Yangsoon; Kim, Bong-Soo; Chun, Jongsik; Yong, Ji Hyun; Lee, Yeong Seon; Yoo, Jung Sik; Yong, Dongeun; Hong, Seong Geun; D'Souza, Roshan; Thomson, Kenneth S; Lee, Kyungwon; Chong, Yunsop

    2014-01-01

    We analyzed the whole genome sequence and resistome of the outbreak Klebsiella pneumoniae strain MP14 and compared it with those of K. pneumoniae carbapenemase- (KPC-) producing isolates that showed high similarity in the NCBI genome database. A KPC-2-producing multidrug-resistant (MDR) K. pneumoniae clinical isolate was obtained from a patient admitted to a Korean hospital in 2011. The strain MP14 was resistant to all tested β-lactams including monobactam, amikacin, levofloxacin, and cotrimoxazole, but susceptible to tigecycline and colistin. Resistome analysis showed the presence of β-lactamase genes including bla KPC-2, bla SHV-11, bla TEM-169, and bla OXA-9. MP14 also possessed aac(6'-)Ib, aadA2, and aph(3'-)Ia as aminoglycoside resistance-encoding genes, mph(A) for macrolides, oqxA and oqxB for quinolone, catA1 for phenicol, sul1 for sulfonamide, and dfrA12 for trimethoprim. Both SNP tree and cgMLST analysis showed the close relatedness with the KPC producers (KPNIH strains) isolated from an outbreak in the USA and colistin-resistant strains isolated in Italy. The plasmid-scaffold genes in plasmids pKpQil, pKpQil-IT, pKPN3, or pKPN-IT were identified in MP14, KPNIH, and Italian strains. The KPC-2-producing MDR K. pneumoniae ST258 stain isolated in Korea was highly clonally related with MDR K. pneumoniae strains from the USA and Italy. Global spread of KPC-producing K. pneumoniae is a worrying phenomenon.

  16. Clonality and Resistome Analysis of KPC-Producing Klebsiella pneumoniae Strain Isolated in Korea Using Whole Genome Sequencing

    Directory of Open Access Journals (Sweden)

    Yangsoon Lee

    2014-01-01

    Full Text Available We analyzed the whole genome sequence and resistome of the outbreak Klebsiella pneumoniae strain MP14 and compared it with those of K. pneumoniae carbapenemase- (KPC- producing isolates that showed high similarity in the NCBI genome database. A KPC-2-producing multidrug-resistant (MDR K. pneumoniae clinical isolate was obtained from a patient admitted to a Korean hospital in 2011. The strain MP14 was resistant to all tested β-lactams including monobactam, amikacin, levofloxacin, and cotrimoxazole, but susceptible to tigecycline and colistin. Resistome analysis showed the presence of β-lactamase genes including blaKPC-2, blaSHV-11, blaTEM-169, and blaOXA-9. MP14 also possessed aac(6′-Ib, aadA2, and aph(3′-Ia as aminoglycoside resistance-encoding genes, mph(A for macrolides, oqxA and oqxB for quinolone, catA1 for phenicol, sul1 for sulfonamide, and dfrA12 for trimethoprim. Both SNP tree and cgMLST analysis showed the close relatedness with the KPC producers (KPNIH strains isolated from an outbreak in the USA and colistin-resistant strains isolated in Italy. The plasmid-scaffold genes in plasmids pKpQil, pKpQil-IT, pKPN3, or pKPN-IT were identified in MP14, KPNIH, and Italian strains. The KPC-2-producing MDR K. pneumoniae ST258 stain isolated in Korea was highly clonally related with MDR K. pneumoniae strains from the USA and Italy. Global spread of KPC-producing K. pneumoniae is a worrying phenomenon.

  17. Molecular and serological characterization of the first Leptospira santarosai strain isolated from a dog.

    Science.gov (United States)

    Miotto, Bruno Alonso; Moreno, Luisa Zanolli; Guilloux, Aline Gil Alves; Sousa, Gisele Oliveira de; Loureiro, Ana Paula; Moreno, Andrea Micke; Lilenbaum, Walter; Vasconcellos, Silvio Arruda; Heinemann, Marcos Bryan; Hagiwara, Mitika Kuribayashi

    2016-10-01

    Leptospirosis is a zoonotic disease of global importance caused by pathogenic Leptospira species. Dogs can become asymptomatically infected, acting like reservoir hosts for pathogenic Leptospira, notably Leptospira interrogans serovar Canicola. Identification of such individuals and characterization of leptospires involved in chronic infections may unravel the role of dogs in the epidemiology of particular leptospiral strains. The aim of the present work was to describe the first Leptospira santarosai strain isolated from a dog. The dog was kept in a public shelter in São Paulo city, Brazil, and presented asymptomatic urinary shedding detected by PCR. Prospective evaluation was performed to fully characterize its chronic carrier state. The dog did not present anti-Leptospira titles or clinical/laboratorial abnormalities during the evaluations; nevertheless long-term urinary shedding was confirmed by PCR and leptospires were recovered from two occasions. The isolated strain was molecularly characterized by partial 16S rRNA and secY gene sequencing and MLST analysis. Serogroup identification was performed using polyclonal antibodies. The strain was identified as Leptospira santarosai, serogroup Sejroe. This is the first evidence in the literature of the isolation of L. santarosai in dogs. Our findings show that dogs can persistently harbor leptospires other than L. interrogans. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Pullulan-hyperproducing color variant strain of Aureobasidium pullulans FB-1 newly isolated from phylloplane of Ficus sp.

    Science.gov (United States)

    Singh, R S; Saini, G K

    2008-06-01

    The studies were carried out for the isolation of efficient pullulan producing strains of Aureobasidium pullulans. Five strains were isolated from phylloplane of different plants. Amongst these, three were producing black pigment melanin, while the remaining two produced pink pigment. These two color variant isolates of A. pullulans were designated as FB-1 and FG-1, and obtained from phylloplane of Ficus benjamina and Ficus glometa, respectively. The parameters employed for the identification of the isolates included morphology, nutritional assimilation patterns and exopolysaccharide (EPS) production. Isolates were compared with standard cultures for EPS production. A. pullulans FB-1 was the best producer of pullulan giving up to 1.9, 1.4 and 1.7 times more pullulan than the control of A. pullulans NCIM 976, NCIM 1048 and NCIM 1049, respectively. The IR spectra of the isolates and standard strains revealed that the polysaccharide was pullulan, but not aubasidan. The study also supported the fact that A. pullulans is a ubiquitous organism and phylloplane being the important niche of the organism.

  19. Characterization and probiotic potential of Lactobacillus plantarum strains isolated from cheeses.

    Science.gov (United States)

    Zago, Miriam; Fornasari, Maria Emanuela; Carminati, Domenico; Burns, Patricia; Suàrez, Viviana; Vinderola, Gabriel; Reinheimer, Jorge; Giraffa, Giorgio

    2011-08-01

    Ninety-eight Lactobacillus plantarum strains isolated from Italian and Argentinean cheeses were evaluated for probiotic potential. After a preliminary subtractive screening based on the presence of msa and bsh genes, 27 strains were characterized. In general, the selected strains showed high resistance to lysozyme, good adaptation to simulated gastric juice, and a moderate to low bile tolerance. The capacity to agglutinate yeast cells in a mannose-specific manner, as well as the cell surface hydrophobicity was found to be variable among strains. Very high β-galactosidase activity was shown by a considerable number of the tested strains, whereas variable prebiotic utilization ability was observed. Only tetracycline resistance was observed in two highly resistant strains which harbored the tetM gene, whereas none of the strains showed β-glucuronidase activity or was capable of inhibiting pathogens. Three strains (Lp790, Lp813, and Lp998) were tested by in vivo trials. A considerable heterogeneity was found among a number of L. plantarum strains screened in this study, leading to the design of multiple cultures to cooperatively link strains showing the widest range of useful traits. Among the selected strains, Lp790, Lp813, and Lp998 showed the best probiotic potential and would be promising candidates for inclusion as starter cultures for the manufacture of probiotic fermented foods. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Lactobacillus strain diversity based on partial hsp60 gene sequences and design of PCR-restriction fragment length polymorphism assays for species identification and differentiation.

    Science.gov (United States)

    Blaiotta, Giuseppe; Fusco, Vincenzina; Ercolini, Danilo; Aponte, Maria; Pepe, Olimpia; Villani, Francesco

    2008-01-01

    A phylogenetic tree showing diversities among 116 partial (499-bp) Lactobacillus hsp60 (groEL, encoding a 60-kDa heat shock protein) nucleotide sequences was obtained and compared to those previously described for 16S rRNA and tuf gene sequences. The topology of the tree produced in this study showed a Lactobacillus species distribution similar, but not identical, to those previously reported. However, according to the most recent systematic studies, a clear differentiation of 43 single-species clusters was detected/identified among the sequences analyzed. The slightly higher variability of the hsp60 nucleotide sequences than of the 16S rRNA sequences offers better opportunities to design or develop molecular assays allowing identification and differentiation of either distant or very closely related Lactobacillus species. Therefore, our results suggest that hsp60 can be considered an excellent molecular marker for inferring the taxonomy and phylogeny of members of the genus Lactobacillus and that the chosen primers can be used in a simple PCR procedure allowing the direct sequencing of the hsp60 fragments. Moreover, in this study we performed a computer-aided restriction endonuclease analysis of all 499-bp hsp60 partial sequences and we showed that the PCR-restriction fragment length polymorphism (RFLP) patterns obtainable by using both endonucleases AluI and TacI (in separate reactions) can allow identification and differentiation of all 43 Lactobacillus species considered, with the exception of the pair L. plantarum/L. pentosus. However, the latter species can be differentiated by further analysis with Sau3AI or MseI. The hsp60 PCR-RFLP approach was efficiently applied to identify and to differentiate a total of 110 wild Lactobacillus strains (including closely related species, such as L. casei and L. rhamnosus or L. plantarum and L. pentosus) isolated from cheese and dry-fermented sausages.

  1. An Entamoeba sp. strain isolated from rhesus monkey is virulent but genetically different from Entamoeba histolytica.

    Science.gov (United States)

    Tachibana, Hiroshi; Yanagi, Tetsuo; Pandey, Kishor; Cheng, Xun-Jia; Kobayashi, Seiki; Sherchand, Jeevan B; Kanbara, Hiroji

    2007-06-01

    An Entamoeba sp. strain, P19-061405, was isolated from a rhesus monkey in Nepal and characterized genetically. The strain was initially identified as Entamoeba histolytica using PCR amplification of peroxiredoxin genes. However, sequence analysis of the 18S rRNA gene showed a 0.8% difference when compared to the reference E. histolytica HM-1:IMSS human strain. Differences were also observed in the 5.8S rRNA gene and the internal transcribed spacer (ITS) regions 1 and 2, and analysis of the serine-rich protein gene from the monkey strain showed unique codon usages compared to E. histolytica isolated from humans. The amino acid sequences of two hexokinases and two glucose phosphate isomerases also differed from those of E. histolytica. Isoenzyme analyses of these enzymes in the monkey strain showed different electrophoretic mobility patterns compared with E. histolytica isolates. Analysis of peroxiredoxin genes indicated the presence of at least seven different types of protein, none of which were identical to proteins in E. histolytica. When the trophozoites from the monkey strain were inoculated into the livers of hamsters, formation of amebic abscesses was observed 7 days after the injection. These results demonstrate that the strain is genetically different from E. histolytica and is virulent. Revival of the name Entamoeba nuttalli is proposed for the organism.

  2. Antagonistic effect of Lactobacillus strains against gas-producing coliforms isolated from colicky infants

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    Oggero Roberto

    2011-06-01

    Full Text Available Abstract Background Infantile colic is a common disturb within the first 3 months of life, nevertheless the pathogenesis is incompletely understood and treatment remains an open issue. Intestinal gas production is thought to be one of the causes of abdominal discomfort in infants suffering from colic. However, data about the role of the amount of gas produced by infants' colonic microbiota and the correlation with the onset of colic symptoms are scanty. The benefit of supplementation with lactobacilli been recently reported but the mechanisms by which they exert their effects have not yet been fully defined. This study was performed to evaluate the interaction between Lactobacillus spp. strains and gas-forming coliforms isolated from stools of colicky infants. Results Strains of coliforms were isolated from stools of 45 colicky and 42 control breastfed infants in McConkey Agar and identified using PCR with species-specific primers, and the BBL™ Enterotube™ II system for Enterobacteriaceae. Gas-forming capability of coliforms was assessed in liquid cultures containing lactose as sole carbon source. The average count of total coliforms in colicky infants was significantly higher than controls: 5.98 (2.00-8.76 log10 vs 3.90 (2.50-7.10 CFU/g of faeces (p = 0.015. The following strains were identified: Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae and Enterococcus faecalis. Then, 27 Lactobacillus strains were tested for their antagonistic effect against coliforms both by halo-forming method and in liquid co-cultures. Lactobacillus delbrueckii subsp.delbrueckii DSM 20074 and L. plantarum MB 456 were able to inhibit all coliforms strains (halo-forming method, also in liquid co-cultures, thus demonstrating an antagonistic activity. Conclusions This study shows that two out of 27 strains of Lactobacillus examined possess an antimicrobial effect against six species of gas-forming coliforms

  3. Antagonistic effect of Lactobacillus strains against gas-producing coliforms isolated from colicky infants.

    Science.gov (United States)

    Savino, Francesco; Cordisco, Lisa; Tarasco, Valentina; Locatelli, Emanuela; Di Gioia, Diana; Oggero, Roberto; Matteuzzi, Diego

    2011-06-30

    Infantile colic is a common disturb within the first 3 months of life, nevertheless the pathogenesis is incompletely understood and treatment remains an open issue. Intestinal gas production is thought to be one of the causes of abdominal discomfort in infants suffering from colic. However, data about the role of the amount of gas produced by infants' colonic microbiota and the correlation with the onset of colic symptoms are scanty. The benefit of supplementation with lactobacilli been recently reported but the mechanisms by which they exert their effects have not yet been fully defined. This study was performed to evaluate the interaction between Lactobacillus spp. strains and gas-forming coliforms isolated from stools of colicky infants. Strains of coliforms were isolated from stools of 45 colicky and 42 control breastfed infants in McConkey Agar and identified using PCR with species-specific primers, and the BBL™ Enterotube™ II system for Enterobacteriaceae. Gas-forming capability of coliforms was assessed in liquid cultures containing lactose as sole carbon source. The average count of total coliforms in colicky infants was significantly higher than controls: 5.98 (2.00-8.76) log10 vs 3.90 (2.50-7.10) CFU/g of faeces (p = 0.015). The following strains were identified: Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae and Enterococcus faecalis. Then, 27 Lactobacillus strains were tested for their antagonistic effect against coliforms both by halo-forming method and in liquid co-cultures. Lactobacillus delbrueckii subsp. delbrueckii DSM 20074 and L. plantarum MB 456 were able to inhibit all coliforms strains (halo-forming method), also in liquid co-cultures, thus demonstrating an antagonistic activity. This study shows that two out of 27 strains of Lactobacillus examined possess an antimicrobial effect against six species of gas-forming coliforms isolated from colicky infants. Our findings may stimulate

  4. Draft Genome Sequences from a Novel Clade of Bacillus cereus Sensu Lato Strains, Isolated from the International Space Station

    NARCIS (Netherlands)

    Venkateswaran, Kasthuri; Checinska Sielaff, Aleksandra; Ratnayake, Shashikala; Pope, Robert K; Blank, Thomas E; Stepanov, Victor G; Fox, George E; van Tongeren, Sandra P; Torres, Clinton; Allen, Jonathan; Jaing, Crystal; Pierson, Duane; Perry, Jay; Koren, Sergey; Phillippy, Adam; Klubnik, Joy; Treangen, Todd J; Rosovitz, M J; Bergman, Nicholas H

    2017-01-01

    The draft genome sequences of six Bacillus strains, isolated from the International Space Station and belonging to the Bacillus anthracis-B. cereus-B. thuringiensis group, are presented here. These strains were isolated from the Japanese Experiment Module (one strain), U.S. Harmony Node 2 (three

  5. Genetic characterization of Shiga toxin-producing Escherichia coli O26:H11 strains isolated from animal, food, and clinical samples

    Science.gov (United States)

    Krüger, Alejandra; Lucchesi, Paula M. A.; Sanso, A. Mariel; Etcheverría, Analía I.; Bustamante, Ana V.; Burgán, Julia; Fernández, Luciana; Fernández, Daniel; Leotta, Gerardo; Friedrich, Alexander W.; Padola, Nora L.; Rossen, John W. A.

    2015-01-01

    The Shiga-toxin producing Escherichia coli (STEC) may cause serious illness in human. Here we analyze O26:H11 strains known to be among the most reported STEC strains causing human infections. Genetic characterization of strains isolated from animal, food, and clinical specimens in Argentina showed that most carried either stx1a or stx2a subtypes. Interestingly, stx2a-positive O26:H11 rarely isolated from cattle in other countries showed to be an important proportion of O26:H11 strains circulating in cattle and food in our region. Seventeen percent of the isolates harbored more than one gene associated with antimicrobial resistance. In addition to stx, all strains contained the virulence genes eae-β, tir, efa, iha, espB, cif, espA, espF, espJ, nleA, nleB, nleC, and iss; and all except one contained ehxA, espP, and cba genes. On the other hand, toxB and espI genes were exclusively observed in stx2-positive isolates, whereas katP was only found in stx1a-positive isolates. Our results show that O26:H11 STEC strains circulating in Argentina, including those isolated from humans, cattle, and meat products, present a high pathogenic potential, and evidence that cattle can be a reservoir of O26:H11 strains harboring stx2a. PMID:26539413

  6. Potential probiotic characteristics of Lactobacillus and Enterococcus strains isolated from traditional dadih fermented milk against pathogen intestinal colonization.

    Science.gov (United States)

    Collado, M Carmen; Surono, Ingrid S; Meriluoto, Jussi; Salminen, Seppo

    2007-03-01

    Traditional fermented buffalo milk in Indonesia (dadih) has been believed to have a beneficial impact on human health, which could be related to the properties of the lactic acid bacteria (LAB) involved in its fermentation process. In previous studies, it was discovered that strains of dadih lactic isolates possessed some beneficial properties in vitro. In the present study, the adhesion capacity of specific LAB isolates from dadih to intestinal mucus was analyzed. Further, the ability to inhibit model human pathogens and displace them from mucus was assessed. The adhesion of tested LAB strains was strain-dependent and varied from 1.4 to 9.8%. The most adhesive Lactobacillus plantarum strain was IS-10506, with 9.8% adhesion. The competition assay between dadih LAB isolates and pathogens showed that a 2-h preincubation with L. plantarum at 37 degrees C significantly reduced pathogen adhesion to mucus. All tested LAB strains displaced and inhibited pathogen adhesion, but the results were strain-specific and dependent on time and pathogen strains. In general, L. plantarum IS-10506 showed the best ability against pathogen adhesion.

  7. Isolation and characterization of a biosurfactant producing strain, Brevibacilis brevis HOB1.

    Science.gov (United States)

    Haddad, Namir I A; Wang, Ji; Mu, Bozhong

    2008-12-01

    Biosurfactant-producing bacteria were isolated from the production water of an oil field. Isolates were screened for biosurfactant production using surface tension test. The highest reduction of surface tension was achieved with a bacterial strain which was identified by 16S rRNA gene sequencing as Brevibacilis brevis HOB1. It has been investigated using different carbon and nitrogen sources. It showed that the strain was able to grow and reduce the surface tension of the broth to 29 mN/m on commercial sugar and maltose, and to 32 mN/m on glucose after 72 h of growth. The maximum amount of biosurfactant was obtained when nitrate ions were supplied as nitrogen source. Biosurfactant produced by Brevibacilis brevis HOB1 was confirmed as a lipopeptide class of biosurfactant using TLC test and mass spectra. Lipopeptide isoforms were isolated from cell-free supernatants by acid-precipitation followed by one step of chromatographic separation on solid-phase ODS C18 column. The separation was confirmed by HPLC and ESI Q-TOF MS spectroscopy. Comparing the mass data obtained and the mass numbers reported for the lipopeptide complexes from other strains, it can be concluded that the major lipopeptide product of Brevibacilis brevis HOB1 is the surfactin isoform. This lipopeptide showed strong antibacterial and antifungal activity. It is a candidate for the biocontrol of pathogens in agriculture and other industries.

  8. Isolation and characterization of oral Actinomyces strain from patients with periodontal disease

    Directory of Open Access Journals (Sweden)

    Eshraghi S.

    2001-09-01

    Full Text Available "nAbstract: Actinomyces species are normal residents of the mouth cavity, gastrointestinal tract and female genital tract. The genus consists of gram-positive bacteria, strictly anaerobic or microaerophilic. The bacteria are opportunists with a low virulence potential that cause actinomycosis only when the normal mucosal barriers are disrupted. The main purpose of this study was the isolation of Actinomyces strains and determining of their role in periodontal diseases. The present study was carried out on 100 patients with periodontal diseases referred to the Periodontic Department of Faculty of Dentistry. The sampling was done in 6 months with isolation of oral Actinomyces from microbial plaque and periodontal pocket. The samples were selected based on the following criteria: periodontal plaque with deep pocket (>3 mm, no antibiotic therapy for a period of at least two weeks, and lack of systemic diseases. One strain of Actinomyces viscosus and two strains of Actinomyces naeslundii were isolated from the patients with gingivitis and periodontitis. Of the 100 patients with gingivitis and periodontitis, aged between 18-57 years old, 46% were males and 54% were females. The peak incidence of the diseases (35% was in the third age group (31-40 and the lowest incidence (10% was in the first age group (<20. Forty patients (40% complained of gingival disease and its bleeding with lower incidence of (42.5% in female.

  9. Virulence factors and genetic variability of Staphylococcus aureus strains isolated from raw sheep's milk cheese.

    Science.gov (United States)

    Spanu, Vincenzo; Spanu, Carlo; Virdis, Salvatore; Cossu, Francesca; Scarano, Christian; De Santis, Enrico Pietro Luigi

    2012-02-01

    Contamination of dairy products with Staphylococcus aureus can be of animal or human origin. The host pathogen relationship is an important factor determining genetic polymorphism of the strains and their potential virulence. The aim of the present study was to carry out an extensive characterization of virulence factors and to study the genetic variability of S. aureus strains isolated from raw ewe's milk cheese. A total of 100 S. aureus strains isolated from cheese samples produced in 10 artisan cheese factories were analyzed for the presence of enterotoxins (sea-see) and enterotoxins-like genes (seh, sek, sel, sem, seo, sep), leukocidins, exfoliatins, haemolysins, toxic shock syndrome toxin 1 (TSST-1) and the accessory gene regulator alleles (agr). Strains were also typed using pulsed-field gel electrophoresis (PFGE). AMOVA analysis carried out on PFGE and PCR data showed that the major component explaining genetic distance between strains was the dairy of origin. Of the total isolates 81% had a pathogenicity profile ascribable to "animal" biovar while 16% could be related to "human" biovar. The biovar allowed to estimate the most likely origin of the contamination. Minimum inhibitory concentrations (MICs) of nine antimicrobial agents and the presence of the corresponding genes coding for antibiotic resistance was also investigated. 18 strains carrying blaZ gene showed resistance to ampicillin and penicillin and 6 strains carrying tetM gene were resistant to tetracycline. The presence of mecA gene and methicillin resistance, typical of strains of human origin, was never detected. The results obtained in the present study confirm that S. aureus contamination in artisan cheese production is mainly of animal origin. Copyright © 2011. Published by Elsevier B.V.

  10. Intraspecies cellular fatty acids heterogeneity of Lactobacillus plantarum strains isolated from fermented foods in Ukraine.

    Science.gov (United States)

    Garmasheva, I; Vasyliuk, O; Kovalenko, N; Ostapchuk, A; Oleschenko, L

    2015-09-01

    The intraspecies heterogeneity of cellular fatty acids composition of Lactobacillus plantarum strains isolated from Ukrainian traditional fermented foods was examined. Seven cellular fatty acids were identified. All Lact. plantarum strains investigated contained C16:0 (from 7·54 to 49·83% of total fatty acids), cC18:1 (3·23-38·67% of total fatty acids) and cycC19:0 acids (9·03-67·68% of total fatty acids) as the major fatty acids. The tC18:1 acid made up 1·47-22·0% of the total fatty acids. The C14:0 and C16:1 acids were present in small amounts (0·22-6·96% and 0·66-7·42% respectively) in most Lact. plantarum strains. Differences in relative contents of some fatty acids between Lact. plantarum strains depending on the source isolation were found. Isolates of dairy origin contained slightly greater levels of the C16:0 and tC18:1 fatty acids and lower levels of the cC18:1 than strains obtained from fermented vegetables. The origin of Lact. plantarum strains affects their fatty acids composition, which in turn, appears to be related to their ability to growth under stress factors. Cellular fatty acids composition is an important chemotaxonomic characteristic of bacterial cells. At the same time cellular fatty acids play a key role in maintaining the viability of micro-organisms in different environmental conditions. In this study, intraspecies heterogeneity of cellular fatty acids composition of Lactobacillus plantarum strains was examined. This work provides novel and important information about a relationship between cellular fatty acids composition of Lact. plantarum strains and source of isolation or stress resistance profile. Our results showed that cellular fatty acids composition is quite diverse among Lact. plantarum strains derived from different sources and may reflect previous cell's history. Our findings should be considered in chemotaxonomic studies of lactic acid bacteria and its ecology. © 2015 The Society for Applied Microbiology.

  11. Temporal association between the isolation of Sabin-related poliovirus vaccine strains and the Guillain-Barré syndrome

    OpenAIRE

    Friedrich, F.; Filippis, A. M. B.; Schatzmayr, H. G.

    1996-01-01

    Thirty eight paralysis cases classified as Guillain-Barré syndrome (GBS) in Brazil were analysed. In all these cases Sabin-related poliovirus vaccine strains were isolated. In most of the cases the last vaccine dose was given months or years before the onset of GBS, suggesting a persistent infection or the transmission of the Sabin-related strains to the patients. The isolation of Sabin-related strains from GBS cases some days or weeks after the onset of the disease, demonstrated a temporal a...

  12. Antibacterial effect of roselle extracts (Hibiscus sabadariffa), sodium hypochlorite and acetic acid against multidrug-resistant Salmonella strains isolated from tomatoes.

    Science.gov (United States)

    Gutiérrez-Alcántara, E J; Rangel-Vargas, E; Gómez-Aldapa, C A; Falfan-Cortes, R N; Rodríguez-Marín, M L; Godínez-Oviedo, A; Cortes-López, H; Castro-Rosas, J

    2016-02-01

    Antibiotic-resistant Salmonella strains were isolated from saladette and red round type tomatoes, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One hundred saladette tomato samples and 100 red round tomato samples were collected from public markets. Each sample consisted of four whole tomatoes. Salmonella was isolated from the samples by conventional culture procedure. Susceptibility to 16 antibiotics was tested for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle calyx extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite and acetic acid against antibiotic-resistant Salmonella isolates was evaluated on contaminated tomatoes. Twenty-four Salmonella strains were isolated from 12% of each tomato type. Identified Salmonella serotypes were Typhimurium and Typhi. All isolated strains exhibited resistance to at least three antibiotics and some to as many as 12. Over contaminated tomatoes, the roselle calyx extracts produced a greater reduction (2-2·6 log) in antibiotic-resistant Salmonella strain concentration than sodium hypochlorite and acetic acid. The presence of multidrug-resistant Salmonella in vegetables is a significant public health concern. Multidrug-resistant Salmonella strains were isolated from raw tomatoes purchased in public markets in Mexico and challenged with roselle Hibiscus sabdariffa calyx extracts, sodium hypochlorite and acetic acid. On tomatoes, the extracts caused a greater reduction in the concentration of antibiotic-resistant Salmonella strains than sodium hypochlorite and acetic acid. Roselle calyx extracts are a potentially useful addition to disinfection procedures of raw tomatoes in the field, processing plants, restaurants and homes. © 2015 The Society for Applied Microbiology.

  13. Induced systemic resistance against Botrytis cinerea by Micromonospora strains isolated from root nodules

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    Pilar eMartínez-Hidalgo

    2015-09-01

    Full Text Available Micromonospora is a Gram positive bacterium that can be isolated from nitrogen fixing nodules from healthy leguminous plants, where they could be beneficial to the plant. Their plant growth promoting activity in legume and non-legume plants has been previously demonstrated. The present study explores the ability of Micromonospora strains to control fungal pathogens and to stimulate plant immunity. Micromonospora strains isolated from surface sterilized nodules of alfalfa showed in vitro antifungal activity against several pathogenic fungi. Moreover, root inoculation of tomato plants with these Micromonospora strains effectively reduced leaf infection by the fungal pathogen Botrytis cinerea, despite spatial separation between both microorganisms. This induced systemic resistance, confirmed in different tomato cultivars, is long lasting. Gene expression analyses evidenced that Micromonospora stimulates the plant capacity to activate defense mechanisms upon pathogen attack. The defensive response of tomato plants inoculated with Micromonospora spp. differs from that of non-inoculated plants, showing a stronger induction of jasmonate-regulated defenses when the plant is challenged with a pathogen. The hypothesis of jasmonates playing a key role in this defense priming effect was confirmed using defense-impaired tomato mutants, since the JA-deficient line def1 was unable to display a long term induced resistance upon Micromonospora spp. inoculation.In conclusion, nodule isolated Micromonospora strains should be considered excellent candidates as biocontrol agents as they combine both direct antifungal activity against plant pathogens and the ability to prime plant immunity.

  14. [Isolation, identification and characterization of a diethylstilbestrol-degrading bacterial strain Serratia sp].

    Science.gov (United States)

    Xu, Ran-Fang; Sun, Min-Xia; Liu, Juan; Wang, Hong; Li, Xin; Zhu, Xue-Zhu; Ling, Wan-Ting

    2014-08-01

    Utilizing the diethylstilbestrol (DES)-degrading bacteria to biodegrade DES is a most reliable technique for cleanup of DES pollutants from the environment. However, little information is available heretofore on the isolation of DES-degrading bacteria and their DES removal performance in the environment. A novel bacterium capable of degrading DES was isolated from the activated sludge of a wastewater treatment plant. According to its morphology, physiochemical characteristics, and 16S rDNA sequence analysis, this strain was identified as Serratia sp.. The strain was an aerobic bacterium, and it could degrade 68.3% of DES (50 mg x L(-1)) after culturing for 7 days at 30 degrees C, 150 r x min(-1) in shaking flasks. The optimal conditions for DES biodegradation by the obtained strain were 30 degrees C, 40-60 mg x L(-1) DES, pH 7.0, 5% of inoculation volume, 0 g x L(-1) of added NaCl, and 10 mL of liquid medium volume in 100 mL flask.

  15. Is there ethological isolation among Drosophila melanogaster strains reared for more than 35 generations on different food?

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    Pavković-Lučić Sofija

    2009-01-01

    Full Text Available Ethological isolation among three strains of D. melanogaster reared for more than 35 generations on different food (standard cornmeal-agar-yeast medium, banana, and tomato was tested in a series of multiple choice tests. Long-term maintenance on different substrates did not contribute to sexual isolation among three 'nutritional strains', as degrees of ethological isolation (Malogolowkin-Cohen's isolation indices were not statistically significant. Males and females reared on different nutritional resources were equally successful in matings, i.e., significant differences in the number of copulations achieved by males and females from various lines were not observed.

  16. Features of Lactobacillus sakei isolated from Italian sausages: focus on strains from Ventricina del Vastese

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    Carmela Amadoro

    2015-12-01

    Full Text Available In this study bacterial isolates from Ventricina del Vastese sausage, previously identified as Lactobacillus (L. sakei, were characterised genotypically, physiologically and on the basis of some technologically relevant traits. A total of 70 L. sakei isolates from sausages manufactured with spontaneous fermentation in the same producing plant were taken into account. Six genotypic groups were distinguished on the basis of Rep-polymerase chain reaction with the GTG5 primer, some of which were found only in the sausages ripened at temperatures lower than 10°C for the first two months and lower than 16°C for the remaining three months, according to the traditional ripening process. Six strains were selected as representative of the genotypic profiles and further characterised. A high diversity in their fermentation profiles was observed, and different groups were separated on the basis of growth and acidifying capacity in meat extract. None of the strains produced histamine or tyramine in vitro. One strain was able to slightly inhibit Listeria (L. monocytogenes and L. innocua and all six strains were able to slightly inhibit Enterobacteriaceae isolated from Ventricina del Vastese sausages in vitro. Results showed that most L. sakei strains can have a role in improving the safety of low acidity fermented sausages, even though a limited acidifying capacity was observed in a meat-like substrate, and that L. sakei strains able to produce biogenic amines are unlikely to occur in spontaneously fermented meat products.

  17. Survey of strain distribution and antibiotic resistance pattern of group B streptococci (Streptococcus agalactiae isolated from clinical specimens

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    Mousavi, Seyed Masoud

    2016-09-01

    Full Text Available Aim: The aims of the present study were to determine the antibiotic susceptibility profils with particular emphasis on susceptible or resistant strains to macrolides and lincosamids antibiotics and to determine possible antibiotic resistance mechanisms occurring in group B streptococci (GBS strains using PCR assay and disk diffusion method.Methods: A total of 62 clinical GBS strains were investigated. Antibacterial susceptibility testing was performed using the disk diffusion method and inducible resistance test for clindamycin by standard double disk diffusion or D-zone test for all isolates to differentiate macrolide resistance phenotype (M, constitutive macrolide-lincosamide-streptogramin B phenotype (cMLS and induced macrolide-lincosamide-streptogramin B phenotype (iMLS. In addition, minimum inhibitory concentrations (MIC of penicillin were determined for all isolates. Finally, possible existence of antibiotic resistance genes for erythromycin , and and for clindamycin were examined among isolates using PCR assay.Results: All 62 isolates were susceptible to penicillin, ampicillin, linezolid, cefazoline and vancomycin. However, 93.5% (n=58 of isolates showed an increased MIC to penicillin. The overall rate of erythromycin resistance was 35.5% (n=22. All erythromycin-resistant isolates displayed the M phenotype (100%, n=22. All three erythromycin resistance genes (i.e. , and were found in erythromycin-resistant isolates.Conclusion: It was concluded that prescribing antibiotic without antibacterial susceptibility tests should be prevented because of the high prevalence of erythromycin-resistant GBS strains and the fact that erythromycin-resistant GBS strains has shown an increased MIC to penicillin, as the drug of choice for treating GBS infections.

  18. FERMENTATION OF INULIN BY A NEW STRAIN OF CLOSTRIDIUM-THERMOAUTOTROPHICUM ISOLATED FROM DAHLIA TUBERS

    NARCIS (Netherlands)

    DRENT, WJ; GOTTSCHAL, JC

    1991-01-01

    A new inulin-fermenting strain of Clostridium thermoautotrophicum was isolated through enrichment on dahlia tubers, and subsequent plating on agar media with undissolved inulin. Both the cell-bound and cell-free inulinase(s) functioned optimally at 60-degrees-C and at neutral pH. This new strain I1

  19. Sexual selection, sexual isolation and pheromones in Drosophila melanogaster strains after long-term maintaining on different diets.

    Science.gov (United States)

    Trajković, Jelena; Miličić, Dragana; Savić, Tatjana; Pavković-Lučić, Sofija

    2017-07-01

    Evolution of reproductive isolation may be a consequence of a variety of signals used in courtship and mate preferences. Pheromones play an important role in both sexual selection and sexual isolation. The abundance of pheromones in Drosophila melanogaster may depend on different environmental factors, including diet. The aim of this study was to ascertain to which degree principal pheromones affect sexual selection in D. melanogaster. We used D. melanogaster strains reared for 14 years on four substrates: standard cornmeal substrate and those containing tomato, banana and carrot. We have previously determined that long-term maintaining of these dietary strains resulted in differences in their cuticular hydrocarbons profile (CHs). In this work, we have tested the level of sexual selection and sexual isolation between aforementioned strains. We found that the high levels of cis-vaccenyl acetate, 7-pentacosene and 7,11-nonacosadiene in the strain reared on a substrate containing carrot affected the individual attractiveness and influenced sexual isolation between flies of this strain and flies reared on a substrate containing banana. Based on these results, long-term different diets, may contribute, to sexual behaviour of D. melanogaster via the effects of principal pheromones. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Phylogenetic analysis, fumonisin production and pathogenicity of Fusarium fujikuroi strains isolated from rice in the Philippines.

    Science.gov (United States)

    Cruz, Alejandra; Marín, Patricia; González-Jaén, M Teresa; Aguilar, Kristel Grace I; Cumagun, Christian Joseph R

    2013-09-01

    Fusarium fujikuroi Nirenberg is a maize and rice pathogen causing important agricultural losses and produces fumonisins - mycotoxins which pose health risk to humans and farm animals. However, little information is available about the phylogenetics of this species and its ability to produce fumonisins in rice. We studied 32 strains isolated from rice in the Philippines and performed a phylogenetic analysis using the partial sequence of Elongation Factor 1 alpha (EF-1α) including isolates belonging to closely related species. Fumonisin B1 (FB1 ) production was analyzed in 7-day-old cultures grown in fumonisin-inducing medium by an enzyme-linked immunosorbent assay-based method and by real-time reverse transcriptase-polymerase chain reaction using primers for FUM1 gene, a key gene in fumonisin biosynthesis. Nucleotide diversities per site (π) were 0.00024 ± 0.00022 (standard deviation) for the 32 F. fujikuroi strains from the Philippines and 0.00189 ± 0.00143 for all 34 F. fujikuroi strains, respectively. F. fujikuroi isolates grouped into one cluster separated from the rest of isolates belonging to the closely related F. proliferatum and showed very low variability, irrespective of their geographic origin. The cluster containing strains of F. proliferatum showed higher intraspecific variability than F. fujikuroi. Thirteen of the 32 strains analyzed were FB1 producers (40.62%), with production ranging from 0.386 to 223.83 ppm. All isolates analyzed showed FUM1 gene expression above 1 and higher than the CT value of the non-template control sample. Both seedling stunting and elongation were induced by the isolates in comparison with the control. F. fujikuroi are distinct from F. proliferatum isolates based on phytogenetic analysis and are potential fumonisin producers because all are positive for FUM1 gene expression. No relationship between fumonisin production and pathogenicity could be observed. © 2013 Society of Chemical Industry.

  1. Environmental carbonate chemistry selects for phenotype of recently isolated strains of Emiliania huxleyi

    Science.gov (United States)

    Rickaby, Rosalind E. M.; Hermoso, Michaël; Lee, Renee B. Y.; Rae, Benjamin D.; Heureux, Ana M. C.; Balestreri, Cecilia; Chakravarti, Leela; Schroeder, Declan C.; Brownlee, Colin

    2016-05-01

    Coccolithophorid algae, particularly Emiliania huxleyi, are prolific biomineralisers that, under many conditions, dominate communities of marine eukaryotic plankton. Their ability to photosynthesise and form calcified scales (coccoliths) has placed them in a unique position in the global carbon cycle. Contrasting reports have been made with regards to the response of E. huxleyi to ocean acidification. Therefore, there is a pressing need to further determine the fate of this key organism in a rising CO2 world. In this paper, we investigate the phenotype of newly isolated, genetically diverse, strains of E. huxleyi from UK Ocean Acidification Research Programme (UKOA) cruises around the British Isles, the Arctic, and the Southern Ocean. We find a continuum of diversity amongst the physiological and photosynthetic parameters of different strains of E. huxleyi morphotype A under uniform, ambient conditions imposed in the laboratory. This physiology is best explained by adaptation to carbonate chemistry in the former habitat rather than being prescribed by genetic fingerprints such as the coccolithophore morphology motif (CMM). To a first order, the photosynthetic capacity of each strain is a function of both aqueous CO2 availability, and calcification rate, suggestive of a link between carbon concentrating ability and calcification. The calcification rate of each strain is related linearly to the natural environmental [CO32-] at the site of isolation, but a few exceptional strains display low calcification rates at the highest [CO32-] when calcification is limited by low CO2 availability and/or a lack of a carbon concentrating mechanism. We present O2-electrode measurements alongside coccolith oxygen isotopic composition and the uronic acid content (UAC) of the coccolith associated polysaccharide (CAP), that act as indirect tools to show the differing carbon concentrating ability of the strains. The environmental selection revealed amongst our recently isolated strain

  2. Diversity of Saccharomyces cerevisiae strains isolated from Borassus akeassii palm wines from Burkina Faso in comparison to other African beverages.

    Science.gov (United States)

    Tapsoba, François; Legras, Jean-Luc; Savadogo, Aly; Dequin, Sylvie; Traore, Alfred Sababenedyo

    2015-10-15

    In South-West of Burkina Faso, palm wine is produced by spontaneous fermentation of the sap from a specific palm tree Borassus akeassii and plays an important role in people's lives. Saccharomyces cerevisiae is the main agent of this alcoholic fermentation but little is known about the diversity of the isolates from palm. In this work, 39 Saccharomyces cerevisiae strains were isolated from palm wine samples collected from 14 sites in Burkina Faso, as well as 7 isolates obtained from sorghum beer (Dolo) from 3 distant sites. Their diversity was analyzed at 12 microsatellite loci, and compared to the genotypes obtained for other African yeast populations isolated from Cocoa hulks from Ghana, sorghum beer from Ivory Coast, palm wine from Djibouti Republic, and to our database of strains from miscellaneous origins (bread, beer, wine, sake, oaks…). The ploidy of these strains has been assessed as well by flow cytometry. Our results show that B. akeassii palm wine contains a specific yeast population of diploid strains, different from Dolo produced in the same area and from other palm wine strains from Ivory Coast, Nigeria, or Djibouti Republic. In contrast, Dolo strains appeared as a group of related and mainly tetraploid strains despite being isolated from different countries. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Screening of Probiotic Activities of Lactobacilli Strains Isolated from Traditional Tibetan Qula, A Raw Yak Milk Cheese

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    Bei Zhang

    2016-10-01

    Full Text Available In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42% had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (p<0.001. Further screening performed on the above 20 isolates indicated that all 20 lactobacilli strains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%, Lactobacillus plantarum 1086-1 (82%, Lactobacillus casei 1089 (81%, Lactobacillus casei 1138 (79%, Lactobacillus buchneri 1059 (78

  4. Isolation and characterization of new facultative alkaliphilic Bacillus flexus strains from maize processing waste water (nejayote).

    Science.gov (United States)

    Sanchez-Gonzalez, M; Blanco-Gamez, A; Escalante, A; Valladares, A G; Olvera, C; Parra, R

    2011-04-01

    This work describes the isolation and characterization of two new alkaliphilic micro-organisms present in nejayote. Samples of fresh industrial nejayote were plated on nejayote medium and incubated for 4 days at 37 °C. Isolates were identified based on morphological and physiological characteristics, as well as 16S rDNA sequence analysis. Two gram-positive strains, NJY2 and NJY4, able to hydrolyse starch, xylan, and gelatin were isolated from nejayote. Comparative sequence analysis of 16S rDNA and phylogenetic studies indicate that the micro-organisms studied were closely related to members of the Bacillus flexus species. The strains were identified as facultative alkaliphilic salt tolerant bacteria. Isolate NJY2 produced cell associated phenolic acid esterases, able to release ferulic acid from nixtamalised corn bran and ethyl and methyl esters. The isolated strains of B. flexus NJY2 and NJY4 showed important physiological properties to produce high-value molecules from agroindustrial by-products. This is the first report about the isolation of alkaliphilic micro-organisms from nejayote and the first report of phenolic acid esterases synthesised by alkaliphiles. The new alkaliphilic micro-organisms have potential application in the treatment and transformation of tortilla industry residues. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  5. Investigation of the Antimicrobial Activity of Bacillus licheniformis Strains Isolated from Retail Powdered Infant Milk Formulae.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Begley, Máire; Clifford, Tanya; Deasy, Thérèse; Considine, Kiera; O'Connor, Paula; Ross, R Paul; Hill, Colin

    2014-03-01

    This study investigated the potential antimicrobial activity of ten Bacillus licheniformis strains isolated from retail infant milk formulae against a range of indicator (Lactococcus lactis, Lactobacillus bulgaricus and Listeria innocua) and clinically relevant (Listeria monocytogenes, Staphylococcus aureus, Streptococcus agalactiae, Salmonella Typhimurium and Escherichia coli) microorganisms. Deferred antagonism assays confirmed that all B. licheniformis isolates show antimicrobial activity against the Gram-positive target organisms. PCR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses indicated that four of the B. licheniformis isolates produce the bacteriocin lichenicidin. The remaining six isolates demonstrated a higher antimicrobial potency than lichenicidin-producing strains. Further analyses identified a peptide of ~1,422 Da as the most likely bioactive responsible for the antibacterial activity of these six isolates. N-terminal sequencing of the ~1,422 Da peptide from one strain identified it as ILPEITXIFHD. This peptide shows a high homology to the non-ribosomal peptides bacitracin and subpeptin, known to be produced by Bacillus spp. Subsequent PCR analyses demonstrated that the six B. licheniformis isolates may harbor the genetic machinery needed for the synthesis of a non-ribosomal peptide synthetase similar to those involved in production of subpeptin and bacitracin, which suggests that the ~1,422 Da peptide might be a variant of subpeptin and bacitracin.

  6. Antimicrobial susceptibilities of Listeria monocytogenes human strains isolated from 1970 to 2008 in Brazil

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    Cristhiane Moura Falavina dos Reis

    2011-04-01

    Full Text Available INTRODUCTION: Listeria monocytogenes is the causative agent of listeriosis, a foodborne illness that affects mainly pregnant women, the elderly and immunocompromised patients. The primary treatment is a combination of ampicillin with an aminoglycoside, in addition to a second-choice drug represented by chloramphenicol, erythromycin, tetracycline and rifampicin. The aim of this study was to analyze the antimicrobial susceptibility profile of strains isolated from human sources in the last four decades. METHODS: Sixty-eight strains were selected from the culture collection of the Laboratory of Bacterial Zoonoses/LABZOO/FIOCRUZ isolated in different regions of Brazil from 1970 to 2008 and primarily isolated from cerebrospinal fluid and blood culture. Susceptibility tests to antimicrobials drugs were evaluated using the criteria established by Soussy using the Kirby-Bauer method and E-Test strips were used to determine the minimum inhibitory concentration (MIC. RESULTS: Among the strains tested, serovar L4b (60.3% was the most prevalent, followed by serovar 1/2a (20.6%, 1/2b (13.2% and the more uncommon serovars 1/2c, 3b and 4ab (5.9%. All strains were susceptible to ampicillin, cephalothin, erythromycin, gentamicin, teicoplanin and vancomycin. Only one strain (1.5% showed resistance to rifampin, and two (3% were resistant to trimethoprim-sulfamethoxazole. MICs with values up to 2μg/ml reinforce the need for microbiological surveillance. CONCLUSIONS: The study demonstrated low prevalence of strains resistant to the antimicrobial drugs indicated in the treatment of human listeriosis. Monitoring antimicrobial resistance profile is still very important to determine adequate treatment, especially in immunocompromised patients.

  7. Full-length genome sequence analysis of four subgroup J avian leukosis virus strains isolated from chickens with clinical hemangioma.

    Science.gov (United States)

    Lin, Lulu; Wang, Peikun; Yang, Yongli; Li, Haijuan; Huang, Teng; Wei, Ping

    2017-12-01

    Since 2014, cases of hemangioma associated with avian leukosis virus subgroup J (ALV-J) have been emerging in commercial chickens in Guangxi. In this study, four strains of the subgroup J avian leukosis virus (ALV-J), named GX14HG01, GX14HG04, GX14LT07, and GX14ZS14, were isolated from chickens with clinical hemangioma in 2014 by DF-1 cell culture and then identified with ELISA detection of ALV group specific antigen p27, the detection of subtype specific PCR and indirect immunofluorescence assay (IFA) with ALV-J specific monoclonal antibody. The complete genomes of the isolates were sequenced and it was found that the gag and pol were relatively conservative, while env was variable especially the gp85 gene. Homology analysis of the env gene sequences showed that the env gene of all the four isolates had higher similarities with the hemangioma (HE)-type reference strains than that of the myeloid leukosis (ML)-type strains, and moreover, the HE-type strains' specific deletion of 205-bp sequence covering the rTM and DR1 in 3'UTR fragment was also found in the four isolates. Further analysis on the sequences of subunits of env gene revealed an interesting finding: the gp85 of isolates GX14ZS14 and GX14HG04 had a higher similarity with HPRS-103 and much lower similarity with the HE-type reference strains resulting in GX14ZS14, GX14HG04, and HPRS-103 being clustered in the same branch, while gp37 had higher similarities with the HE-type reference strains when compared to that of HPRS-103, resulted in GX14ZS14, GX14HG04, and HE-type reference strains being clustered in the same branch. The results suggested that isolates GX14ZS14 and GX14HG04 may be the recombinant strains of the foreign strain HPRS-103 with the local epidemic HE-type strains of ALV-J.

  8. Screening of Lactobacillus strains for their ability to bind benzo(a)pyrene and the mechanism of the process.

    Science.gov (United States)

    Zhao, Hongfei; Zhou, Fang; Qi, Yeqiong; Dziugan, Piotr; Bai, Fengling; Walczak, Piotr; Zhang, Bolin

    2013-09-01

    In order to investigate the binding ability of Lactobacillus strains to Benzo(a)pyrene (BaP), 15 strains were analysed. L. plantarum CICC 22135 and L. pentosus CICC 23163 exhibited high efficiency in removing BaP from aqueous medium; the binding rates were 66.76% and 64.31%, respectively. This process was affected by temperature, incubation time and pH, and cell viability was not necessary for the binding ability. Additionally, both strains, especially strain CICC 23163 showed high specificity in binding BaP. The cell-BaP complexes were stable in aqueous medium. The mechanism of binding was investigated by examining the binding ability of different components of the microorganism cells. The results revealed that peptidoglycans played an important role in binding BaP and its structural integrity was required. Consequently, we proposed that the mechanism of this process was a physisorption and peptidoglycan was the main binding site. These two strains may be used for dietary detoxification in human diet and animal feed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Draft genome sequences of eight bacteria isolated from the indoor environment: Staphylococcus capitis strain H36, S. capitis strain H65, S. cohnii strain H62, S. hominis strain H69, Microbacterium sp. strain H83, Mycobacterium iranicum strain H39, Plantibacter sp. strain H53, and Pseudomonas oryzihabitans strain H72

    OpenAIRE

    Lymperopoulou, Despoina S.; Coil, David A.; Schichnes, Denise; Lindow, Steven E.; Jospin, Guillaume; Eisen, Jonathan A.; Adams, Rachel I.

    2017-01-01

    We report here the draft genome sequences of eight bacterial strains of the genera Staphylococcus, Microbacterium, Mycobacterium, Plantibacter, and Pseudomonas. These isolates were obtained from aerosol sampling of bathrooms of five residences in the San Francisco Bay area. Taxonomic classifications as well as the genome sequence and gene annotation of the isolates are described. As part of the ?Built Environment Reference Genome? project, these isolates and associated genome data provide val...

  10. Antagonistic activities of some Bifidobacterium sp. strains isolated from resident infant gastrointestinal microbiota on Gram-negative enteric pathogens.

    Science.gov (United States)

    Delcaru, Cristina; Alexandru, Ionela; Podgoreanu, Paulina; Cristea, Violeta Corina; Bleotu, Coralia; Chifiriuc, Mariana Carmen; Bezirtzoglou, Eugenia; Lazar, Veronica

    2016-06-01

    The gastrointestinal microbiota contributes to the consolidation of the anti-infectious barrier against enteric pathogens. The purpose of this study was to investigate the influence of Bifidobacterium sp. strains, recently isolated from infant gastrointestinal microbiota on the in vitro growth and virulence features expression of enteropathogenic bacterial strains. The antibacterial activity of twelve Bifidobacterium sp. strains isolated from human feces was examined in vitro against a wide range of Gram negative pathogenic strains isolated from 30 infant patients (3 days to 5 years old) with diarrhea. Both potential probiotic strains (Bifidobacterium longum, Bifidobacterium pseudocatenulatum, Bifidobacterium catenulatum, Bifidobacterium breve, Bifidobacterium ruminantium) and enteropathogenic strains (EPEC, EIEC, Klebsiella pneumoniae, Salmonella sp., Yersinia enterocolitica, Pseudomonas aeruginosa) were identified by MALDI-TOF and confirmed serologically when needed. The bactericidal activity, growth curve, adherence to the cellular HEp-2 substratum and production of soluble virulence factors have been assessed in the presence of different Bifidobacterium sp. cultures and fractions (whole culture and free-cell supernatants). Among the twelve Bifidobacterium sp. strains, the largest spectrum of antimicrobial activity against 9 of the 18 enteropathogenic strains was revealed for a B. breve strain recently isolated from infant intestinal feces. The whole culture and free-cell supernatant of B. breve culture decreased the multiplication rate, shortened the log phase and the total duration of the growth curve, with an earlier entrance in the decline phase and inhibited the adherence capacity to a cellular substratum and the swimming/swarming motility too. These results indicate the significant probiotic potential of the B. breve strain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Enterotoxigenic Genes in strains of Staphylococcus spp., isolated from cheese made in Pamplona-Colombia

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    Fanny Herrera A.

    2015-01-01

    Full Text Available Objective. To determine the incidence of coagulase-positive strains of enterotoxigenic Staphylococcus in doble crema (double cream cheese samples produced in Pamplona. Materials and methods. Bacterial isolation was performed following the routine method for coagulase positive Staphylococcus provided by the Colombian Technical Standard 4779, by using Baird Parker medium with confirmation of typical colonies by performing the coagulase test. Detection of genes for principal enterotoxins was done by PCR. Results. The prevalence of coagulase positive Staphylococcus in cheese samples was 31%, with 27% of the samples failing to meet the requirements of the NTC 750. In 24.6% of the studied isolates, genes for enterotoxin production were detected. The presence, in the isolated strains, of genes for SEB, SEA and SED was 18.5%, 4.6% and 3.0%, respectively. Conclusions. The significant presence of enterotoxigenic genes found in the isolates obtained from samples of double cream cheese made in Pamplona, suggests an important hazard to the health of consumers.

  12. [Identification of two cyanobacterial strains isolated from the Kotel'nikovskii hot spring of the Baikal rift].

    Science.gov (United States)

    Sorokovnikova, E G; Tikhonova, I V; Belykh, O I; Klimenkov, I V; Likhoshvaĭ, E V

    2008-01-01

    Two cyanobacterial strains, Pseudanabaena sp. 0411 and Synechococcus sp. 0431, were isolated from a sample collected in the Kotel'nikovskii hot spring of the Baikal rift. According to the results of light and transmission electron microscopy, as well as of the phylogenetic analysis of the 16S rRNA gene, these cyanobacteria were classified as Pseudanabaena sp. nov. and Synechococcus bigranulatus Skuja. The constructed phylogenetic tree shows that the studied strains are positioned in the clades of cyanobacteria isolated from hydrothermal vents of Asia and New Zealand, separately from marine and freshwater members of these genera, including those isolated from Lake Baikal.

  13. The sensitivity to antibiotics of strains of group B streptococcus isolates from pregnant women in Belgrade

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    Jovanović Luka

    2016-01-01

    Full Text Available Introduction: Group B streptococcus (GBS is a significant human pathogen. GBS colonizes the vagina and it is one of the most important causes of early neonatal sepsis and meningitis. In many countries, screening of pregnant women and intrapartal use of antibiotics are common practice. Macrolide and lincosamide resistant strains of GBS are a significant problem, because these antibiotics are the second line therapy in case of penicillin allergy. Aim: Our aim was to investigate the frequency of antibiotic resistant strains of GBS and to detect macrolide resistance phenotypes in GBS strains obtained from pregnant women in Belgrade. Material and Methods: 105 GBS isolates were obtained from vaginal swabs of pregnant women attending two Gynecology and Obstetrics Centers in Belgrade. The isolates were tested for antimicrobial susceptibility pattern and D test were performed on Mueller Hinton agar. Results: Macrolide and lincosamide resistance was found in 30.4 %, and 23.8 % of isolates, respectively. There was a high frequency of tetracycline resistant strains (88.6 %. Most frequent macrolide resistant phenotype was iMLSb (macrolide and inducibile lincosamide resistance (62.4%. Conclusion: The results of our study indicate that there is a high level of macrolide resistance among GBS isolates in Serbia and the active surveillance is needed.

  14. Antimicrobial Resistant Pattern of Escherichia Coli Strains Isolated from Pediatric Patients in Jordan

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    Mohammad Alshara

    2011-05-01

    Full Text Available The present study was conducted to investigate antimicrobial resistant pattern of Escherichia coli (E. coli strains isolated from clinical specimens of Jordanian pediatric patients during the period from January to December 2008. A total of 444 E. coli strains were isolated from clinical specimens and tested for their susceptibility to different antimicrobial drugs. Overall, high resistance rate was observed for ampicillin (84%, followed by amoxicillin-clavulanic acid (74.3%, cotrimoxazole (71%, nalidixic acid (47.3%, cephalothin (41%. Lower resistance rates were observed for amikacin (0% followed by Cefotaxime (11%, Ceftriaxone (11.7%, ciprofloxacin (14.5%, Norfloxacin (16.5%, gentamicin (17.3% cephalexin (20.9%, Ceftazidime (22.5%, cefixime (29.6%, and cefaclor (32.8%. Ampicillin, amoxicillin-clavulanic acid and cotrimoxazole were found to be ineffective at in vitro inhibition of the E. coli of pediatric origin. Amikacin was highly effective for E. coli with susceptibility rate of 100%. The majority of E. coli strains were susceptible to third generation cephalosporins and fluoroquinolones.

  15. Detection of enterotoxins and genotyping of Staphylococcus aureus strains isolated from Isfahan Educational Hospital, Iran

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    Seyed Asghar Havaei

    2017-10-01

    Full Text Available Background and aims: Staphylococcus aureus is known as one of the most important nosocomial pathogens, which may lead to several infections. The aim of this study was determining the enterotoxins A, C, and TSST-1 and molecular characterization of S. aureus strains with PFGE and MLST typing methods. Materials and methods: In the present study during the sixmonths sampling, fifty S. aureus strains were isolated from patients admitted to Al-Zahra university hospital. Antimicrobial susceptibility testing, Multiplex PCR for detection of enterotoxin A, C and TSST-1, pulse field gel electrophoresis (PFGE and multilocus sequence typing (MLST were used for molecular typing. Results: In antibiogram the highest and lowest percentage of resistance was belonged to tetracycline and rifampin respectively. Multiplex PCR indicated that 30% of the strains harbored sea and 34% harbored sec genes. However, only 4% of our collected isolates had tsst gene. In PFGE method analysis on all S. aureus strains, a total of 19 different patterns were identified. Nine various sequence types in 27 selected S. aureus isolates were identified by MLST. Conclusions: Present study indicates a possible higher variability among our S. aureus strains by two different molecular typing methods; nevertheless four main common types (CT1, CT7, CT9, and CT11 with at least one toxin genes were determined.

  16. Whole-Genome Sequencing and Comparative Genome Analysis of Bacillus subtilis Strains Isolated from Non-Salted Fermented Soybean Foods.

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    Mayumi Kamada

    Full Text Available Bacillus subtilis is the main component in the fermentation of soybeans. To investigate the genetics of the soybean-fermenting B. subtilis strains and its relationship with the productivity of extracellular poly-γ-glutamic acid (γPGA, we sequenced the whole genome of eight B. subtilis stains isolated from non-salted fermented soybean foods in Southeast Asia. Assembled nucleotide sequences were compared with those of a natto (fermented soybean food starter strain B. subtilis BEST195 and the laboratory standard strain B. subtilis 168 that is incapable of γPGA production. Detected variants were investigated in terms of insertion sequences, biotin synthesis, production of subtilisin NAT, and regulatory genes for γPGA synthesis, which were related to fermentation process. Comparing genome sequences, we found that the strains that produce γPGA have a deletion in a protein that constitutes the flagellar basal body, and this deletion was not found in the non-producing strains. We further identified diversity in variants of the bio operon, which is responsible for the biotin auxotrophism of the natto starter strains. Phylogenetic analysis using multilocus sequencing typing revealed that the B. subtilis strains isolated from the non-salted fermented soybeans were not clustered together, while the natto-fermenting strains were tightly clustered; this analysis also suggested that the strain isolated from "Tua Nao" of Thailand traces a different evolutionary process from other strains.

  17. Molecular and Phenotypic Characterization of Escherichia coli O26:H8 among Diarrheagenic E. coli O26 Strains Isolated in Brazil

    Science.gov (United States)

    Piazza, Roxane M. F.; Delannoy, Sabine; Fach, Patrick; Saridakis, Halha O.; Pedroso, Margareth Z.; Rocha, Letícia B.; Gomes, Tânia A. T.; Vieira, Mônica A. M.; Beutin, Lothar

    2013-01-01

    Escherichia coli strains of serogroup O26 comprise two distinct groups of pathogens, characterized as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC). Among the several genes related to type III secretion system-secreted effector proteins, espK was found to be highly specific for EHEC O26:H11 and its stx-negative derivative strains isolated in European countries. E. coli O26 strains isolated in Brazil from infant diarrhea, foods, and the environment have consistently been shown to lack stx genes and are thus considered atypical EPEC. However, no further information related to their genetic background is known. Therefore, in this study, we aimed to discriminate and characterize these Brazilian O26 stx-negative strains by phenotypic, genetic, and biochemical approaches. Among 44 isolates confirmed to be O26 isolates, most displayed flagellar antigen H11 or H32. Out of the 13 nonmotile isolates, 2 tested positive for fliCH11, and 11 were fliCH8 positive. The identification of genetic markers showed that several O26:H11 and all O26:H8 strains tested positive for espK and could therefore be discriminated as EHEC derivatives. The presence of H8 among EHEC O26 and its stx-negative derivative isolates is described for the first time. The interaction of three isolates with polarized Caco-2 cells and with intestinal biopsy specimen fragments ex vivo confirmed the ability of the O26 strains analyzed to cause attaching-and-effacing (A/E) lesions. The O26:H32 strains, isolated mostly from meat, were considered nonvirulent. Knowledge of the virulence content of stx-negative O26 isolates within the same serotype helped to avoid misclassification of isolates, which certainly has important implications for public health surveillance. PMID:23974139

  18. Genotypic and biological characteristics of non-identified strain of spotted fever group rickettsiae isolated in Crimea.

    Science.gov (United States)

    Balayeva, N M; Demkin, V V; Rydkina, E B; Ignatovich, V F; Artemiev, M I; Lichoded LYa; Genig, V A

    1993-12-01

    A strain of rickettsiae, designated Crimea-108, was isolated from ticks Dermacentor marginatus in the Crimea in 1977. Its immunobiological characteristics involve low pathogenicity for experimental animals, moderate infectivity for chick embryos, and antigenic relatedness to spotted fever group (SFG) rickettsiae (R. sibirica, R. conorii, R. akari), especially to R. sibirica. The genotypic characterization of the strain Crimea-108 was carried out in comparison with SFG and typhus group rickettsiae by using restriction fragment length polymorphism (RFLP) analysis and DNA-probe hybridization. The marked similarity was detected between DNA restriction patterns of the strains Crimea-108, R. sibirica and R. conorii, but each of them besides comigrating fragments had specific ones. Genotypic analysis of the strain Crimea-108, the SFG and typhus group rickettsiae by three independent DNA probes, based on R. prowazekii DNA, gave unique hybridization patterns for the Crimea-108 strain with all probes. The obtained data show that the Crimea-108 isolate does not belong to the species of R. sibirica, R. conorii, R. akari. The strain Crimea-108 is a novel strain of SFG rickettsiae for the Crimea region.

  19. Isolation of coagulase-positive staphylococci from bitches' colostrum and milk and genetic typing of methicillin-resistant Staphylococcus pseudintermedius strains.

    Science.gov (United States)

    Rota, Ada; Corrò, Michela; Drigo, Ilenia; Bortolami, Alessio; Börjesson, Stefan

    2015-07-23

    Among the coagulase-positive, potentially pathogenic staphylococci, Staphylococcus pseudintermedius has been frequently isolated from bitches' milk. This organism colonizes the mammary gland or causes infection, while S. aureus has been only occasionally reported. The objective of this study was to investigate the occurrence and persistence of coagulase-positive staphylococci in the colostrum and milk of postpartum bitches, either treated or untreated with antimicrobials, and to assess the incidence, antibiotic resistance profile and genetic type of the methicillin-resistant strains. On postpartum D1, D7 and D15, drops of secretion were collected from the mammary glands of 27 postpartum bitches, nine of which were treated with antimicrobials. Coagulase-positive staphylococci were identified, antimicrobial susceptibility and the presence of mecA were tested and the genetic profile of methicillin-resistant strains was assessed. Staphylococcus pseudintermedius was the only coagulase-positive staphylococcus isolated, and its presence was detected in 21 out of 27 bitches and in 66 out of 145 swabs. In a single bitch, it caused puerperal mastitis. In untreated bitches, the frequency of isolation was lower in colostrum than in milk. All of the isolates except one were resistant to at least three antimicrobial classes, while 14 out of 66 S. pseudintermedius strains were methicillin-resistant mecA positive (MRSP) and were isolated from eight bitches housed in the same breeding kennel. A significant association was found between antimicrobial treatment and the presence of MRSP. Six of the 12 typed isolates belonged to spa-type t02 carrying SCCmec II/III, and another six were non-typeable with spa carrying SCCmec IV. The t02-SCCmec II/III isolates were sequence type (ST) 71; four NT-SCCmec IV isolates were ST258 and two were ST369. PFGE showed that isolates from the same dog had identical band patterns, while isolates from different dogs had unique band patterns. MRSP strains

  20. In Vitro characterization of Lactococcus lactis strains Isolated from Iranian Traditional Dairy Products as a Potential Probiotic

    Directory of Open Access Journals (Sweden)

    Fatemeh Nejati

    2015-12-01

    Full Text Available Few studies have been reported regarding probiotic properties of Lactococcus lactis strains although they are extensively used as starter cultures in the production of dairy products. In this study 8 wild isolates of Lactococcus lactis were evaluated in vitro with regard to resistance to simulated gastric and intestinal juices, adherence ability to Caco-2 cells and HT29-MTX-E12 cell lines, anti-microbial activity, hydrophobicity and antibiotic susceptibility. The results revealed that all isolates had better survival after exposure to simulated gastrointestinal tract stresses in comparison to control probiotic Lactobacillus rhamnosus GG. Regarding adherence efficiency, almost all isolates exhibited similar adherence with control. Three isolates showed antibacterial activity against Gram-positive pathogens (Staphylococcus aureus and Listeria monocytogenes through spot-agar method. Almost all isolates (seven out of eight showed similar hydrophobicity to control probiotic. Regarding to antibiotic resistance, all isolates were susceptible to gentamicin, ampicillin, ciprofloxacin, erythromycin, tetracycline, penicillin, kanamycin and nitrofurantoin. Although, further investigations are necessary, it was concluded that strains derived from raw milk and home-made dairy products could be a remarkable reservoir for identification of new potential probiotic strains.

  1. Probiotic properties of Lactobacillus strains isolated from Tibetan kefir grains.

    Directory of Open Access Journals (Sweden)

    Yongchen Zheng

    Full Text Available The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB isolated from Tibetan kefir grains. Three Lactobacillus isolates identified as Lactobacillus acidophilus LA15, Lactobacillus plantarum B23 and Lactobacillus kefiri D17 that showed resistance to acid and bile salts were selected for further evaluation of their probiotic properties. The 3 selected strains expressed high in vitro adherence to Caco-2 cells. They were sensitive to gentamicin, erythromycin and chloramphenicol and resistant to vancomycin with MIC values of 26 µg/ml. All 3 strains showed potential bile salt hydrolase (BSH activity, cholesterol assimilation and cholesterol co-precipitation ability. Additionally, the potential effect of these strains on plasma cholesterol levels was evaluated in Sprague-Dawley (SD rats. Rats in 4 treatment groups were fed the following experimental diets for 4 weeks: a high-cholesterol diet, a high-cholesterol diet plus LA15, a high-cholesterol diet plus B23 or a high-cholesterol diet plus D17. The total cholesterol, triglyceride and low-density lipoprotein cholesterol levels in the serum were significantly (P<0.05 decreased in the LAB-treated rats compared with rats fed a high-cholesterol diet without LAB supplementation. The high-density lipoprotein cholesterol levels in groups B23 and D17 were significantly (P<0.05 higher than those in the control and LA15 groups. Additionally, both fecal cholesterol and bile acid levels were significantly (P<0.05 increased after LAB administration. Fecal lactobacilli counts were significantly (P<0.05 higher in the LAB treatment groups than in the control groups. Furthermore, the 3 strains were detected in the rat small intestine, colon and feces during the feeding trial. The bacteria levels remained high even after the LAB administration had been stopped for 2 weeks. These results suggest that these strains may be used in the future as probiotic starter cultures for

  2. Probiotic Properties of Lactobacillus Strains Isolated from Tibetan Kefir Grains

    Science.gov (United States)

    Zheng, Yongchen; Lu, Yingli; Wang, Jinfeng; Yang, Longfei; Pan, Chenyu; Huang, Ying

    2013-01-01

    The objective of this study was to evaluate the functional properties of lactic acid bacteria (LAB) isolated from Tibetan kefir grains. Three Lactobacillus isolates identified as Lactobacillus acidophilus LA15, Lactobacillus plantarum B23 and Lactobacillus kefiri D17 that showed resistance to acid and bile salts were selected for further evaluation of their probiotic properties. The 3 selected strains expressed high in vitro adherence to Caco-2 cells. They were sensitive to gentamicin, erythromycin and chloramphenicol and resistant to vancomycin with MIC values of 26 µg/ml. All 3 strains showed potential bile salt hydrolase (BSH) activity, cholesterol assimilation and cholesterol co-precipitation ability. Additionally, the potential effect of these strains on plasma cholesterol levels was evaluated in Sprague-Dawley (SD) rats. Rats in 4 treatment groups were fed the following experimental diets for 4 weeks: a high-cholesterol diet, a high-cholesterol diet plus LA15, a high-cholesterol diet plus B23 or a high-cholesterol diet plus D17. The total cholesterol, triglyceride and low-density lipoprotein cholesterol levels in the serum were significantly (P<0.05) decreased in the LAB-treated rats compared with rats fed a high-cholesterol diet without LAB supplementation. The high-density lipoprotein cholesterol levels in groups B23 and D17 were significantly (P<0.05) higher than those in the control and LA15 groups. Additionally, both fecal cholesterol and bile acid levels were significantly (P<0.05) increased after LAB administration. Fecal lactobacilli counts were significantly (P<0.05) higher in the LAB treatment groups than in the control groups. Furthermore, the 3 strains were detected in the rat small intestine, colon and feces during the feeding trial. The bacteria levels remained high even after the LAB administration had been stopped for 2 weeks. These results suggest that these strains may be used in the future as probiotic starter cultures for manufacturing

  3. Genome comparison and physiological characterization of eight Streptococcus thermophilus strains isolated from Italian dairy products

    DEFF Research Database (Denmark)

    Vendramin, Veronica; Treu, Laura; Campanaro, Stefano

    2017-01-01

    to identify the core and the variable genes, which vary among strains from 196 to 265. Additionally, correlation between the isolation site and the genetic distance was investigated at genomic level. Results highlight that the phylogenetic reconstruction differs from the geographical strain distribution...

  4. Isolation and characterization of exopolysaccharide produced by Vibrio harveyi strain VB23.

    Science.gov (United States)

    Bramhachari, P V; Dubey, S K

    2006-11-01

    The aim of the study was to isolate and characterize exopolysaccharide (EPS) produced by Vibrio harveyi strain VB23. Growth and EPS production by V. harveyi strain VB23, was studied in mineral salts medium supplemented with NaCl (1.5%) and glucose (0.2%). The rate of EPS production in batch cultures was highest during the late log phase of growth when compared with stationary growth phase. The exopolymer was recovered from the culture supernatant by using a cold ethanol precipitation-dialysis procedure. Chemical analyses of EPS revealed that it is primarily composed of neutral sugars, uronic acids, proteins and sulfates. The purified EPS revealed prominent functional reactive groups, such as hydroxyl, carboxylic and amides, which correspond to a typical heteropolymeric polysaccharide and the EPS, also possessed good emulsification activity. The gas chromatographic analysis of an alditol acetate-derivatized sample of EPS revealed that it is composed primarily of galactose and glucose. Minor components found were rhamnose, fucose, ribose, arabinose, xylose and mannose. The EPS produced by V. harveyi strain VB23 is a heteropolysaccharide possessing good emulsification activity. EPS was readily isolated from culture supernatants, which suggests that the EPS was a slime-like EPS. This is the first report of EPS characterization in luminous V. harveyi bacteria, which describes the isolation and characterization of an EPS expressed by V. harveyi. The results of the study contributes significantly towards an understanding of the chemical composition and applications of the EPS in environmental biotechnology and bioremediation.

  5. [Genetic characterisation of Powassan virus (POWV) isolated from Haemophysalis longicornis ticks in Primorye and two strains of Tick-borne encephalitis virus (TBEV) (Flaviviridae, Flavivirus): Alma-Arasan virus (AAV) isolated from Ixodes persulcatus ticks in Kazakhstan and Malyshevo virus isolated from Aedes vexans nipponii mosquitoes in Khabarovsk kray].

    Science.gov (United States)

    L'vov, D K; Al'khovskiĭ, S V; Shchelkanov, M Iu; Deriabin, P G; Gitel'man, A K; Botikov, A G; Aristova, V A

    2014-01-01

    The complete genomes of the three tick-borne flaviviruses (genus Flavivirus, fam. Bunyaviridae) were sequenced: Povassan virus (POWV, strain LEIV-3070Prm, isolated from Haemophysalis logicornis in Primorsky Krai, Russia in 1977), Alma-Arasan virus (AAV, strain LEIV-1380Kaz, isolated from Ixodes persulcatus ticks in Kazakhstan in 1977) and Malyshevo virus (isolated from a pool of Aedes vexans nipponii mosquitoes, in the Khabarovsk Krai, Russia in 1978). It is shown that AAV and Malyshevo virus are the strains of Tick-borne encephalitis virus (TBEV) and belong to Sibirian and Far-Eastern genotypes, respectively (GenBank ID: AAV KJ744033; strain Malyshevo KJ744034). Phylogenetically AAV is closest related (94,6% nt and 98,3% aa identity) to TBEV strains, isolated in Sibiria (Vasilchenko, Aino, Chita-653, Irkutsk-12). Malyshevo virus is closest related (96,4% nt and 98,3% nt identity) to strains of TBEV, isolated in Far Eastern part of Russia (1230, Spassk-72, Primorye-89). POWV LEIV-3070Prm has 99.7% identity with the prototype strain POWV LB, isolated in Canada and 99.5% of isolates with Far-Eastern strains of POWV (Spassk-9 and Nadezdinsk-1991).

  6. Brewing characteristics of haploid strains isolated from sake yeast Kyokai No. 7.

    Science.gov (United States)

    Katou, Taku; Kitagaki, Hiroshi; Akao, Takeshi; Shimoi, Hitoshi

    2008-11-01

    Sake yeast exhibit various characteristics that make them more suitable for sake brewing compared to other yeast strains. Since sake yeast strains are Saccharomyces cerevisiae heterothallic diploid strains, it is likely that they have heterozygous alleles on homologous chromosomes (heterozygosity) due to spontaneous mutations. If this is the case, segregation of phenotypic traits in haploid strains after sporulation and concomitant meiosis of sake yeast strains would be expected to occur. To examine this hypothesis, we isolated 100 haploid strains from Kyokai No. 7 (K7), a typical sake yeast strain in Japan, and compared their brewing characteristics in small-scale sake-brewing tests. Analyses of the resultant sake samples showed a smooth and continuous distribution of analytical values for brewing characteristics, suggesting that K7 has multiple heterozygosities that affect brewing characteristics and that these heterozygous alleles do segregate after sporulation. Correlation and principal component analyses suggested that the analytical parameters could be classified into two groups, indicating fermentation ability and sake flavour. (c) 2008 John Wiley & Sons, Ltd.

  7. Longitudinal genotyping of Candida dubliniensis isolates reveals strain maintenance, microevolution, and the emergence of itraconazole resistance.

    LENUS (Irish Health Repository)

    Fleischhacker, M

    2010-05-01

    We investigated the population structure of 208 Candida dubliniensis isolates obtained from 29 patients (25 human immunodeficiency virus [HIV] positive and 4 HIV negative) as part of a longitudinal study. The isolates were identified as C. dubliniensis by arbitrarily primed PCR (AP-PCR) and then genotyped using the Cd25 probe specific for C. dubliniensis. The majority of the isolates (55 of 58) were unique to individual patients, and more than one genotype was recovered from 15 of 29 patients. A total of 21 HIV-positive patients were sampled on more than one occasion (2 to 36 times). Sequential isolates recovered from these patients were all closely related, as demonstrated by hybridization with Cd25 and genotyping by PCR. Six patients were colonized by the same genotype of C. dubliniensis on repeated sampling, while strains exhibiting altered genotypes were recovered from 15 of 21 patients. The majority of these isolates demonstrated minor genetic alterations, i.e., microevolution, while one patient acquired an unrelated strain. The C. dubliniensis strains could not be separated into genetically distinct groups based on patient viral load, CD4 cell count, or oropharyngeal candidosis. However, C. dubliniensis isolates obtained from HIV-positive patients were more closely related than those recovered from HIV-negative patients. Approximately 8% (16 of 194) of isolates exhibited itraconazole resistance. Cross-resistance to fluconazole was only observed in one of these patients. Two patients harboring itraconazole-resistant isolates had not received any previous azole therapy. In conclusion, longitudinal genotyping of C. dubliniensis isolates from HIV-infected patients reveals that isolates from the same patient are generally closely related and may undergo microevolution. In addition, isolates may acquire itraconazole resistance, even in the absence of prior azole therapy.

  8. Cell culture isolation and sequence analysis of genetically diverse US porcine epidemic diarrhea virus strains including a novel strain with a large deletion in the spike gene.

    Science.gov (United States)

    Oka, Tomoichiro; Saif, Linda J; Marthaler, Douglas; Esseili, Malak A; Meulia, Tea; Lin, Chun-Ming; Vlasova, Anastasia N; Jung, Kwonil; Zhang, Yan; Wang, Qiuhong

    2014-10-10

    The highly contagious and deadly porcine epidemic diarrhea virus (PEDV) first appeared in the US in April 2013. Since then the virus has spread rapidly nationwide and to Canada and Mexico causing high mortality among nursing piglets and significant economic losses. Currently there are no efficacious preventive measures or therapeutic tools to control PEDV in the US. The isolation of PEDV in cell culture is the first step toward the development of an attenuated vaccine, to study the biology of PEDV and to develop in vitro PEDV immunoassays, inactivation assays and screen for PEDV antivirals. In this study, nine of 88 US PEDV strains were isolated successfully on Vero cells with supplemental trypsin and subjected to genomic sequence analysis. They differed genetically mainly in the N-terminal S protein region as follows: (1) strains (n=7) similar to the highly virulent US PEDV strains; (2) one similar to the reportedly US S INDEL PEDV strain; and (3) one novel strain most closely related to highly virulent US PEDV strains, but with a large (197aa) deletion in the S protein. Representative strains of these three genetic groups were passaged serially and grew to titers of ∼5-6log10 plaque forming units/mL. To our knowledge, this is the first report of the isolation in cell culture of an S INDEL PEDV strain and a PEDV strain with a large (197aa) deletion in the S protein. We also designed primer sets to detect these genetically diverse US PEDV strains. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Genetic and antigenic relationship of foot-and-mouth disease virus serotype O isolates with the vaccine strain O1/BFS.

    Science.gov (United States)

    Xu, Wanhong; Zhang, Zhidong; Nfon, Charles; Yang, Ming

    2018-05-15

    Foot-and-mouth disease serotype O viruses (FMDV/O) are responsible for the most outbreaks in FMD endemic countries. O1/BFS is one of the recommended FMD/O vaccine strains by World Reference Laboratory for FMD. In the current study, FMDV/O1 BFS vaccine strain and serotype O field isolates (45) were analyzed phylogenetically and antigenically to gain more insight into the genetic and antigenic characteristics of the vaccine strain and field isolates. O1/BFS showed similarity with 89% of the field isolates using a virus neutralization test (VNT). The P1 region encoding the FMDV capsid was sequenced and analysed for 46 strains of FMDV/O. Phylogenetic analysis showed these viruses originated from five continents and covered eight of 11 reported topotypes. Five isolates that demonstrated low antigenic similarities with O1/BFS were analyzed for their antigenic variation at the known neutralizing antigenic sites. Three of the five isolates demonstrated unique amino acid substitutions at various antigenic sites. No unique amino acid substitutions were observed for the other two unmatched isolates. Positively selected residues were identified on the surface of the FMD virus capsid supporting that it is important to continuously monitor field isolates for their antigenic and phenotypic changes. In conclusion, the vaccine strain O1/BFS is likely to confer protection against 89% of the 45 FMDV/O isolates based on VNT. Thus O1/BFS vaccine strain is still suitable for use in global FMD serotype O outbreak control. Combining data from phylogenetic, molecular and antigenic analysis can provide improvements in the process of vaccine selection. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

  10. Effect of CuO Nanoparticles over Isolated Bacterial Strains from Agricultural Soil

    International Nuclear Information System (INIS)

    Concha-Guerrero, S.I.; Pinon-Castillo, H.A.; Luna-Velasco, A.; Orrantia-Borunda, E.; Brito, E.M.S.; Tarango-Rivero, S.H.; Caretta, C.A.; Duran, R.

    2014-01-01

    The increased use of the nanoparticles (NPs) on several processes is notorious. In contrast the eco toxicological effects of NPs have been scarcely studied. The main current researches are related to the oxide metallic NPs. In the present work, fifty-six bacterial strains were isolated from soil, comprising 17 different OTUs distributed into 3 classes: Bacilli (36 strains), Flavobacteria (2 strains), and Gamma proteobacteria (18 strains). Copper oxide nanoparticles (CuONPs) were synthesized using a process of chemical precipitation. The obtained CuONPs have a spherical shape and primary size less than 17 nm. Twenty-one strains were used to evaluate the cytotoxicity of CuONPs and 11 of these strains showed high sensibility. Among those 11 strains, 4 (Brevibacillus later osporus strain CSS8, Chryseobacterium indoltheticum strain CSA28, and Pantoea ananatis strains CSA34 and CSA35) were selected to determine the kind of damage produced. The CuONPs toxic effect was observed at expositions over 25 mg·L -1 and the damage to cell membrane above 160 mg·L -1 . The electron microscopy showed the formation of cavities, holes, membrane degradation, blebs, cellular collapse, and lysis. These toxic effects may probably be due to the ions interaction, the oxide-reduction reactions, and the generation of reactive species

  11. Investigation of Antibiotic Susceptibility Pattern of Staphylococcus aureus Strains Isolated from Patients Referring to Some Treatment Centers of Qom City, Iran

    Directory of Open Access Journals (Sweden)

    Sara Mosaei

    2017-07-01

    Full Text Available Background and Objectives: Staphylococcus aureus is one of the important causes of nosocomial infections. Resistance to various antibiotics, such as beta-lactams, aminoglycosides, and macrolides is one of the major problems in treatment and prevention of infections caused by this bacterium. Therefore, accurate determination of antibiotic susceptibility pattern of organisms isolated from patients can be beneficial in treatment and prevention of dangerous infections. The objective of this study was to isolate S. aureus bacterium and to determine the antibiotic susceptibility pattern of the isolated strains in patients referred to some treatment centers of Qom city. Methods: In this descriptive cross-sectional study, 340 clinical samples, were collected from September 2016 to July 2017. After isolation and primary identification of S. aureus isolates (using standard bacteriology methods, the isolated strains were confirmed by PCR technique and amplification of femA gene as a molecular diagnostic marker of S. aureus. Finally, antibiotic susceptibility pattern of the strains, was determined by disk diffusion method according to CLSI guideline. Results: Out of 340 clinical samples, 86 S. aureus strains were isolated and identified based on phenotypic characteristics. The femA gene was observed only in 45 strains (52.32% based on molecular analysis. The results of the antibiotic susceptibility test showed that the highest resistance was to penicillin (86.04% and the lowest resistance was to chloramphenicol (0%. Conclusion: The results of this study indicated that femA gene cannot by itself identify all the S. aureus strains. Also, with regard to the results of antibiogram test, it seems that antibiotic susceptibility test is necessary for S. aureus strains isolated from patients.

  12. Comparative genomics analyses revealed two virulent Listeria monocytogenes strains isolated from ready-to-eat food.

    Science.gov (United States)

    Lim, Shu Yong; Yap, Kien-Pong; Thong, Kwai Lin

    2016-01-01

    Listeria monocytogenes is an important foodborne pathogen that causes considerable morbidity in humans with high mortality rates. In this study, we have sequenced the genomes and performed comparative genomics analyses on two strains, LM115 and LM41, isolated from ready-to-eat food in Malaysia. The genome size of LM115 and LM41 was 2,959,041 and 2,963,111 bp, respectively. These two strains shared approximately 90% homologous genes. Comparative genomics and phylogenomic analyses revealed that LM115 and LM41 were more closely related to the reference strains F2365 and EGD-e, respectively. Our virulence profiling indicated a total of 31 virulence genes shared by both analysed strains. These shared genes included those that encode for internalins and L. monocytogenes pathogenicity island 1 (LIPI-1). Both the Malaysian L. monocytogenes strains also harboured several genes associated with stress tolerance to counter the adverse conditions. Seven antibiotic and efflux pump related genes which may confer resistance against lincomycin, erythromycin, fosfomycin, quinolone, tetracycline, and penicillin, and macrolides were identified in the genomes of both strains. Whole genome sequencing and comparative genomics analyses revealed two virulent L. monocytogenes strains isolated from ready-to-eat foods in Malaysia. The identification of strains with pathogenic, persistent, and antibiotic resistant potentials from minimally processed food warrant close attention from both healthcare and food industry.

  13. Identification and characterization of thermotolerant acetic acid bacteria strains isolated from coconut water vinegar in Sri Lanka.

    Science.gov (United States)

    Perumpuli, P A B N; Watanabe, Taisuke; Toyama, Hirohide

    2014-01-01

    From the pellicle formed on top of brewing coconut water vinegar in Sri Lanka, three Acetobacter strains (SL13E-2, SL13E-3, and SL13E-4) that grow at 42 °C and four Gluconobacter strains (SL13-5, SL13-6, SL13-7, and SL13-8) grow at 37 °C were identified as Acetobacter pasteurianus and Gluconobacter frateurii, respectively. Acetic acid production by the isolated Acetobacter strains was examined. All three strains gave 4% acetic acid from 6% initial ethanol at 37 °C, and 2.5% acetic acid from 4% initial ethanol at 40 °C. Compared with the two other strains, SL13E-4 showed both slower growth and slower acetic acid production. As well as the thermotolerant SKU1108 strain, the activities of the alcohol dehydrogenase and the aldehyde dehydrogenase of SL13E-2 and SL13E-4 were more stable than those of the mesophilic strain. The isolated strains were used to produce coconut water vinegar at higher temperatures than typically used for vinegar production.

  14. Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

    Science.gov (United States)

    Castillo-Rojas, Gonzalo; Mazari-Hiríart, Marisa; Ponce de León, Sergio; Amieva-Fernández, Rosa I; Agis-Juárez, Raúl A; Huebner, Johannes; López-Vidal, Yolanda

    2013-01-01

    Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

  15. Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

    Directory of Open Access Journals (Sweden)

    Gonzalo Castillo-Rojas

    Full Text Available Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation, respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE. E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species.

  16. Virulence-associated genes, antimicrobial resistance and molecular typing of Salmonella Typhimurium strains isolated from swine from 2000 to 2012 in Brazil.

    Science.gov (United States)

    Almeida, F; Medeiros, M I C; Kich, J D; Falcão, J P

    2016-06-01

    The aims of this study were to assess the pathogenic potential, antimicrobial resistance and genotypic diversity of Salmonella Typhimurium strains isolated in Brazil from swine (22) and the surrounding swine environment (5) from 2000 to 2012 and compare them to the profiles of 43 human strains isolated from 1983 to 2010, which had been previously studied. The presence of 12 SPI-1, SPI-2 and plasmid genes was assessed by PCR, the antimicrobial susceptibility to 13 antimicrobials was determined by the disc diffusion assay and genotyping was performed using pulsed-field gel electrophoresis (PFGE), multiple-locus variable-number of tandem repeats analysis (MLVA) and ERIC-PCR. More than 77·8% of the swine strains carried 10 or more of the virulence markers. Ten (37%) strains isolated from swine were multi-drug resistant (MDR). All the molecular typing techniques grouped the strains in two main clusters. Some strains isolated from swine and humans were allocated together in the PFGE-B2, MLVA-A1, MLVA-B and ERIC-A1 clusters. The genotyping results suggest that some strains isolated from swine and humans may descend from a common subtype and may indicate a possible risk of MDR S. Typhimurium with high frequency of virulence genes isolated from swine to contaminate humans in Brazil. This study provided new information about the pathogenic potential, antimicrobial resistance and genotypic diversity of S. Typhimurium isolates from swine origin in Brazil, the fourth largest producer of pigs worldwide. © 2016 The Society for Applied Microbiology.

  17. Isolation and characterization of atrazine mineralizing Bacillus subtilis strain HB-6.

    Directory of Open Access Journals (Sweden)

    Jinhua Wang

    Full Text Available Atrazine is a widely used herbicide with great environmental concern due to its high potential to contaminate soil and waters. An atrazine-degrading bacterial strain HB-6 was isolated from industrial wastewater and the 16S rRNA gene sequencing identified HB-6 as a Bacillus subtilis. PCR assays indicated that HB-6 contained atrazine-degrading genes trzN, atzB and atzC. The strain HB-6 was capable of utilizing atrazine and cyanuric acid as a sole nitrogen source for growth and even cleaved the s-triazine ring and mineralized atrazine. The strain demonstrated a very high efficiency of atrazine biodegradation with a broad optimum pH and temperature ranges and could be enhanced by cooperating with other bacteria, suggesting its huge potential for remediation of atrazine-contaminated sites. To our knowledge, there are few Bacillus subtilis strains reported that can mineralize atrazine, therefore, the present work might provide some new insights on atrazine remediation.

  18. Metabolic fingerprinting of bacterial strains isolated from northern areas of Pakistan

    International Nuclear Information System (INIS)

    Zaheer, A.; Latif, Z.

    2017-01-01

    The diversity of Plant Growth Promoting Rhizobacteria (PGPR) in the rhizosphere plays a key role in the maintenance of sustainable agricultural system. In this study, samples were obtained from northern areas of Pakistan. Thirty bacterial strains were isolated, purified, characterized biochemically and subjected to the metabolic fingerprinting by performing nitrogen fixation, phosphate solubilization, protease, indole acetic acid (IAA) production, antibiotic susceptibility and heavy metal resistance test, lead acetate assay for the H2S production. Strains showing distinct characteristics were further characterized by 16S rDNA sequencing and characterized as Bacillus pumilus (KT273321), Acinetobacter baumanii (KT273323), Acinetobacter junii (KT273324), Pseudomonas aeruginosa (KT273325), Bacillus circulans (KT273326) and Bacillus cereus (KT273327). As most of the strains show positive results for resistance against heavy metals, phosphate solubilization, nitrogen fixation, IAA production, and so these strains might be utilized for the removal of heavy metals from the ecosystem as well as biofertilizer in agriculture lands of northern areas. (author)

  19. Diversity of Paenibacillus polymyxa strains isolated from the rhizosphere of maize planted in Cerrado soil

    NARCIS (Netherlands)

    Weid, von der I.; Paiva, E.; Nobrega, A.; Elsas, van J.D.; Seldin, L.

    2000-01-01

    Paenibacillus polymyxa populations present in the rhizosphere of maize (cultivar BR-201) planted in Cerrado soil were investigated in order to assess their diversity at four stages of plant growth. A total of 67 strains were isolated and all strains were identified as P. polymyxa by classical

  20. Genetic diversity of clinical and environmental strains of Salmonella enterica serotype Weltevreden isolated in Malaysia.

    Science.gov (United States)

    Thong, K L; Goh, Y L; Radu, S; Noorzaleha, S; Yasin, R; Koh, Y T; Lim, V K E; Rusul, G; Puthucheary, S D

    2002-07-01

    The incidence of food-borne salmonellosis due to Salmonella enterica serotype Weltevreden is reported to be on the increase in Malaysia. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of Salmonella serotype Weltevreden strains from humans and the environment. PFGE of XbaI-digested chromosomal DNA from 95 strains of Salmonella serotype Weltevreden gave 39 distinct profiles with a wide range of Dice coefficients (0.27 to 1.00), indicating that PFGE is very discriminative and that multiple clones of Salmonella serotype Weltevreden exist among clinical and environmental isolates. Strains of one dominant pulsotype (pulsotype X1/X2) appeared to be endemic in this region, as they were consistently recovered from humans with salmonellosis between 1996 and 2001 and from raw vegetables. In addition, the sharing of similar PFGE profiles among isolates from humans, vegetables, and beef provides indirect evidence of the possible transmission of salmonellosis from contaminated raw vegetables and meat to humans. Furthermore, the recurrence of PFGE profile X21 among isolates found in samples of vegetables from one wet market indicated the persistence of this clone. The environment in the wet markets may represent a major source of cross-contamination of vegetables with Salmonella serotype Weltevreden. Antibiotic sensitivity tests showed that the clinical isolates of Salmonella serotype Weltevreden remained drug sensitive but that the vegetable isolates were resistant to at least two antibiotics. To the best of our knowledge, this is the first study to compare clinical and environmental isolates of Salmonella serotype Weltevreden in Malaysia.

  1. Genetic Diversity of Clinical and Environmental Strains of Salmonella enterica Serotype Weltevreden Isolated in Malaysia

    Science.gov (United States)

    Thong, K. L.; Goh, Y. L.; Radu, S.; Noorzaleha, S.; Yasin, R.; Koh, Y. T.; Lim, V. K. E.; Rusul, G.; Puthucheary, S. D.

    2002-01-01

    The incidence of food-borne salmonellosis due to Salmonella enterica serotype Weltevreden is reported to be on the increase in Malaysia. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of Salmonella serotype Weltevreden strains from humans and the environment. PFGE of XbaI-digested chromosomal DNA from 95 strains of Salmonella serotype Weltevreden gave 39 distinct profiles with a wide range of Dice coefficients (0.27 to 1.00), indicating that PFGE is very discriminative and that multiple clones of Salmonella serotype Weltevreden exist among clinical and environmental isolates. Strains of one dominant pulsotype (pulsotype X1/X2) appeared to be endemic in this region, as they were consistently recovered from humans with salmonellosis between 1996 and 2001 and from raw vegetables. In addition, the sharing of similar PFGE profiles among isolates from humans, vegetables, and beef provides indirect evidence of the possible transmission of salmonellosis from contaminated raw vegetables and meat to humans. Furthermore, the recurrence of PFGE profile X21 among isolates found in samples of vegetables from one wet market indicated the persistence of this clone. The environment in the wet markets may represent a major source of cross-contamination of vegetables with Salmonella serotype Weltevreden. Antibiotic sensitivity tests showed that the clinical isolates of Salmonella serotype Weltevreden remained drug sensitive but that the vegetable isolates were resistant to at least two antibiotics. To the best of our knowledge, this is the first study to compare clinical and environmental isolates of Salmonella serotype Weltevreden in Malaysia. PMID:12089269

  2. Genetic diversity, anti-microbial resistance, plasmid profile and frequency of the Vi antigen in Salmonella Dublin strains isolated in Brazil.

    Science.gov (United States)

    Vilela, F P; Frazão, M R; Rodrigues, D P; Costa, R G; Casas, M R T; Fernandes, S A; Falcão, J P; Campioni, F

    2018-02-01

    Salmonella Dublin is strongly adapted to cattle causing enteritis and/or systemic disease with high rates of mortality. However, it can be sporadically isolated from humans, usually causing serious disease, especially in patients with underlying chronic diseases. The aim of this study was to molecularly type S. Dublin strains isolated from humans and animals in Brazil to verify the diversity of these strains as well as to ascertain possible differences between strains isolated from humans and animals. Moreover, the presence of the capsular antigen Vi and the plasmid profile was characterized in addition to the anti-microbial resistance against 15 drugs. For this reason, 113 S. Dublin strains isolated between 1983 and 2016 from humans (83) and animals (30) in Brazil were typed by PFGE and MLVA. The presence of the capsular antigen Vi was verified by PCR, and the phenotypic expression of the capsular antigen was determined serologically. Also, a plasmid analysis for each strain was carried out. The strains studied were divided into 35 different PFGE types and 89 MLVA-types with a similarity of ≥80% and ≥17.5%, respectively. The plasmid sizes found ranged from 2 to >150 kb and none of the strains studied presented the capsular antigen Vi. Resistance or intermediate resistance was found in 23 strains (20.3%) that were resistant to ampicillin, ciprofloxacin, chloramphenicol, imipenem, nalidixic acid, piperacillin, streptomycin and/or tetracycline. The majority of the S. Dublin strains studied and isolated over a 33-year period may descend from a common subtype that has been contaminating humans and animals in Brazil and able to cause invasive disease even in the absence of the capsular antigen. The higher diversity of resistance phenotypes in human isolates, as compared with animal strains, may be a reflection of the different anti-microbial treatments used to control S. Dublin infections in humans in Brazil. © 2017 Blackwell Verlag GmbH.

  3. Comparison of the acidifying activity of Lactococcus lactis subsp. lactis strains isolated from goat's milk and Valdeteja cheese.

    Science.gov (United States)

    Alonso-Calleja, C; Carballo, J; Capita, R; Bernardo, A; García-López, M L

    2002-01-01

    This work was carried out to study the acid production by Lactococcus lactis subsp. lactis strains isolated from goat's milk and goat cheese (Valdeteja variety) in order to select a suitable starter culture for industrial goat cheese manufacturing. The titrable acidity of 45 Lactococcus lactis subsp. lactis strains isolated from a home-made batch of Valdeteja cheese with excellent sensory characteristics was measured over a period of 18 h. The strains were divided into two groups depending on the acid production rate: 20 fast acid producer (F) strains and 25 slow acid producer (S) strains. The kinetic parameters (lag phase, maximum acid production rate and value of upper asymptote curve) of the acid production curves for F and S strains were significantly (P titrable acidity of F and S strains were observed after the second hour of incubation. An F strain acetoin producer (Lactococcus lactis subsp. lactis 470Ch2) was selected as autochthonous starter culture for industrial Valdeteja goat cheese manufacturing.

  4. Two Lactobacillus strains, isolated from breast milk, differently modulate the immune response

    NARCIS (Netherlands)

    Diaz-Ropero, M.P.; Martin, R.; Sierra, S.; Lara-Villoslada, F.; Rodriguez, J.M.; Xaus, J.; Olivares, M.

    2007-01-01

    Aims: The ability of two different Lactobacillus strains (Lactobacillus salivarius CECT5713 and Lactobacillus fermentum CECT5716), isolated from human breast milk, to modulate the immune response was examined. Methods and Results: In rodent bone-marrow-derived macrophages (BMDM), the presence of

  5. Isolation and molecular identification of yeast strains from “Rabilé” a ...

    African Journals Online (AJOL)

    Isolation and molecular identification of yeast strains from “Rabilé” a starter of local fermented drink. Ibrahim Keita, Marius K Somda, Aly Savadogo, Iliassou Mogmenga, Ousmane Koita, Alfred S Traore ...

  6. Characterization of bacterial strains isolated from a beef-processing plant following cleaning and disinfection - Influence of isolated strains on biofilm formation by Sakaï and EDL 933 E. coli O157:H7.

    Science.gov (United States)

    Marouani-Gadri, Nesrine; Augier, Gladys; Carpentier, Brigitte

    2009-07-31

    The objective of this study was to investigate the effects on Escherichia coli O157:H7 biofilm formation of bacteria isolated from meat site surfaces following cleaning and disinfection. We first isolated and identified, to the genus level, strains of the latter organisms. Samples were obtained by swabbing the surfaces of equipment or floors over areas ranging from 315 to 3200 cm(2) in a slaughter hall, a meat cutting room and a meat boning room of a meat-processing plant. The number of bacteria recovered from these surfaces ranged from 10(5) CFU/cm(2). In the slaughter hall, stainless steel was in one case one of the most contaminated materials and in other cases one of the less contaminated. The same observation was made for conveyor belts made of polyvinyl chloride in the boning room. Dominant genera in the meat plant were Staphylococcus and Bacillus which were both 34% of the isolates from the slaughter hall and 14 and 4% respectively of the isolates from the cutting room. Randomly selected isolates of each of the genera recovered from the slaughter hall were cultured with E. coli O157:H7 in meat exudate at 15 degrees C to form dual-organism biofilms on polyurethane. In all cases but one, the isolates increased the numbers of attached E. coli O157:H7. The effects ranged from 0.37 to 1.11 for EDL 933 strain and from 0.19 to 1.38 log (CFU/cm(2)) for Sakaï strain. This is the first time that a resident microbiota of a meat-processing plant has been shown to have a favourable effect on E. coli O157:H7 colonization of a solid surface, which is of great interest from a food safety standpoint.

  7. Multilocus sequence typing and virulence analysis of Haemophilus parasuis strains isolated in five provinces of China.

    Science.gov (United States)

    Wang, Liyan; Ma, Lina; Liu, Yongan; Gao, Pengcheng; Li, Youquan; Li, Xuerui; Liu, Yongsheng

    2016-10-01

    Haemophilus parasuis is the etiological agent of Glässers disease, which causes high morbidity and mortality in swine herds. Although H. parasuis strains can be classified into 15 serovars with the Kielstein-Rapp-Gabrielson serotyping scheme, a large number of isolates cannot be classified and have been designated 'nontypeable' strains. In this study, multilocus sequence typing (MLST) of H. parasuis was used to analyze 48 H. parasuis field strains isolated in China and two strains from Australia. Twenty-six new alleles and 29 new sequence types (STs) were detected, enriching the H. parasuis MLST databases. A BURST analysis indicated that H. parasuis lacks stable population structure and is highly heterogeneous, and that there is no association between STs and geographic area. When an UPGMA dendrogram was constructed, two major clades, clade A and clade B, were defined. Animal experiments, in which guinea pigs were challenged intraperitoneally with the bacterial isolates, supported the hypothesis that the H. parasuis STs in clade A are generally avirulent or weakly virulent, whereas the STs in clade B tend to be virulent. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Draft genome sequences of eight bacteria isolated from the indoor environment: Staphylococcus capitis strain H36, S. capitis strain H65, S. cohnii strain H62, S. hominis strain H69, Microbacterium sp. strain H83, Mycobacterium iranicum strain H39, Plantibacter sp. strain H53, and Pseudomonas oryzihabitans strain H72.

    Science.gov (United States)

    Lymperopoulou, Despoina S; Coil, David A; Schichnes, Denise; Lindow, Steven E; Jospin, Guillaume; Eisen, Jonathan A; Adams, Rachel I

    2017-01-01

    We report here the draft genome sequences of eight bacterial strains of the genera Staphylococcus , Microbacterium, Mycobacterium, Plantibacter, and Pseudomonas . These isolates were obtained from aerosol sampling of bathrooms of five residences in the San Francisco Bay area. Taxonomic classifications as well as the genome sequence and gene annotation of the isolates are described. As part of the "Built Environment Reference Genome" project, these isolates and associated genome data provide valuable resources for studying the microbiology of the built environment.

  9. Isolation and Characterization of an Atypical Metschnikowia sp. Strain from the Skin Scraping of a Dermatitis Patient.

    Directory of Open Access Journals (Sweden)

    Chee Sian Kuan

    Full Text Available A yeast-like organism was isolated from the skin scraping sample of a stasis dermatitis patient in the Mycology Unit Department of Medical Microbiology, University Malaya Medical Centre (UMMC, Kuala Lumpur, Malaysia. The isolate produced no pigment and was not identifiable using chromogenic agar and API 20C AUX. The fungus was identified as Metschnikowia sp. strain UM 1034, which is close to that of Metschnikowia drosophilae based on ITS- and D1/D2 domain-based phylogenetic analysis. However, the physiology of the strain was not associated to M. drosophilae. This pathogen exhibited low sensitivity to all tested azoles, echinocandins, 5-flucytosine and amphotericin B. This study provided insight into Metschnikowia sp. strain UM 1034 phenotype profiles using a Biolog phenotypic microarray (PM. The isolate utilized 373 nutrients of 760 nutrient sources and could adapt to a broad range of osmotic and pH environments. To our knowledge, this is the first report of the isolation of Metschnikowia non-pulcherrima sp. from skin scraping, revealing this rare yeast species as a potential human pathogen that may be misidentified as Candida sp. using conventional methods. Metschnikowia sp. strain UM 1034 can survive in flexible and diverse environments with a generalist lifestyle.

  10. Isolation and partial characterization of pigment-like antibiotics produced by a new strain of Streptosporangium isolated from an Algerian soil.

    Science.gov (United States)

    Boudjella, H; Bouti, K; Zitouni, A; Mathieu, F; Lebrihi, A; Sabaou, N

    2007-07-01

    Identification of a new actinomycete strain Sg3, belonging to the genus Streptosporangium and partial characterization of the produced antibacterial activities. The strain Sg3 was isolated from an Algerian Saharan soil and identified by morphological, chemotaxonomic and phylogenetic analyses to the genus Streptosporangium. The comparison of its physiological characteristics with those of known species of Streptosporangium showed significant differences with the nearest species Streptosporangium carneum. Analysis of the 16S rDNA sequence of strain Sg3 showed a similarity level ranging between 97% and 98.8% within Streptosporangium species, with S. carneum the most closely related. Strain Sg3 showed a red coloured antibacterial activity against gram-positive bacteria on several culture media. The purification of the red pigment by chromatographic methods led to the isolation of three active products. The (1)H nuclear magnetic resonance (NMR), mass, infrared (IR) and ultraviolet-visible (UV-VIS) data of these molecules strongly suggested that they belonged to the quinone-anthracycline group with three or more rings. Strain Sg3 represents a distinct phyletic line suggesting a new genomic species. It produces antibacterial activities identified as quinone-anthracycline aromatics. The quinone-anthracycline antibiotics are known for their antimicrobial and antineoplastic activities and are used in chemotherapy for the treatment of many cancer diseases. The present work constitutes the first stage of a whole series of studies to be realized on these antibiotics before arriving at a possible application.

  11. Resistance and Inactivation Kinetics of Bacterial Strains Isolated from the Non-Chlorinated and Chlorinated Effluents of a WWTP

    Directory of Open Access Journals (Sweden)

    Claudia Coronel-Olivares

    2013-08-01

    Full Text Available The microbiological quality of water from a wastewater treatment plant that uses sodium hypochlorite as a disinfectant was assessed. Mesophilic aerobic bacteria were not removed efficiently. This fact allowed for the isolation of several bacterial strains from the effluents. Molecular identification indicated that the strains were related to Aeromonas hydrophila, Escherichia coli (three strains, Enterobacter cloacae, Kluyvera cryocrescens (three strains, Kluyvera intermedia, Citrobacter freundii (two strains, Bacillus sp. and Enterobacter sp. The first five strains, which were isolated from the non-chlorinated effluent, were used to test resistance to chlorine disinfection using three sets of variables: disinfectant concentration (8, 20 and 30 mg·L−1, contact time (0, 15 and 30 min and water temperature (20, 25 and 30 °C. The results demonstrated that the strains have independent responses to experimental conditions and that the most efficient treatment was an 8 mg·L−1 dose of disinfectant at a temperature of 20 °C for 30 min. The other eight strains, which were isolated from the chlorinated effluent, were used to analyze inactivation kinetics using the disinfectant at a dose of 15 mg·L−1 with various retention times (0, 10, 20, 30, 60 and 90 min. The results indicated that during the inactivation process, there was no relationship between removal percentage and retention time and that the strains have no common response to the treatments.

  12. Isolation and genome sequencing of four Arctic marine Psychrobacter strains exhibiting multicopper oxidase activity.

    Science.gov (United States)

    Moghadam, Morteza Shojaei; Albersmeier, Andreas; Winkler, Anika; Cimmino, Lorenzo; Rise, Kjersti; Hohmann-Marriott, Martin Frank; Kalinowski, Jörn; Rückert, Christian; Wentzel, Alexander; Lale, Rahmi

    2016-02-16

    Marine cold-temperature environments are an invaluable source of psychrophilic microbial life for new biodiscoveries. An Arctic marine bacterial strain collection was established consisting of 1448 individual isolates originating from biota, water and sediment samples taken at a various depth in the Barents Sea, North of mainland Norway, with an all year round seawater temperature of 4 °C. The entire collection was subjected to high-throughput screening for detection of extracellular laccase activity with guaiacol as a substrate. In total, 13 laccase-positive isolates were identified, all belonging to the Psychrobacter genus. From the most diverse four strains, based on 16S rRNA gene sequence analysis, all originating from the same Botryllus sp. colonial ascidian tunicate sample, genomic DNA was isolated and genome sequenced using a combined approach of whole genome shotgun and 8 kb mate-pair library sequencing on an Illumina MiSeq platform. The genomes were assembled and revealed genome sizes between 3.29 and 3.52 Mbp with an average G + C content of around 42%, with one to seven plasmids present in the four strains. Bioinformatics based genome mining was performed to describe the metabolic potential of these four strains and to identify gene candidates potentially responsible for the observed laccase-positive phenotype. Up to two different laccase-like multicopper oxidase (LMCO) encoding gene candidates were identified in each of the four strains. Heterologous expression of P11F6-LMCO and P11G5-LMCO2 in Escherichia coli BL21 (DE3) resulted in recombinant proteins exhibiting 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and guaiacol oxidizing activity. Thirteen Psychrobacter species with laccase-positive phenotype were isolated from a collection of Arctic marine bacteria. Four of the isolates were genome sequenced. The overall genome features were similar to other publicly available Psychrobacter genome sequences except for P11G5 harboring seven

  13. Sequence analysis of the first C2 subgenogroup strain of enterovirus 71 isolated in Korea.

    Science.gov (United States)

    Lee, Jung-Ah; Yoon, Young Sil; Hyeon, Ji-Yeon; Yoo, Jung Sik; Lee, Sang-Won; Lee, June-Woo; Lee, Sang-Won

    2016-12-01

    Enterovirus 71 (EV71) is an important causative agent of hand-foot-and-mouth disease with severe neurological complications, which may lead to death in children. Large outbreaks caused by EV71 have frequently occurred in Asia-Pacific region. In Korea, the outbreaks have been caused by EV71 subgenogroups C3, and C4. Only genogroup C, especially subgenogroup C1, C3, C4, and C5, has been detected by the national enterovirus surveillance system in Korea. This study reports the first isolation of EV71 A1451 strain, which belongs to subgenogroup C2. EV71 was isolated from a Korean patient with meningoencephalitis. Complete genome analysis and phylogenetic analysis was performed to identify the characteristics of the strain. Comparative genome analysis of the A1451 strain indicated that this novel C2 strain is associated with the Taiwan strains, which are recombinant virus combined with subgenogroup C2 and B3. Because the subgenogroup B3 was not previously detected in Korea, the A1451 strain is regarded as an imported recombinant virus. Periodic surveillance of EV71 is required to control the spread of this disease and its introduction from overseas. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Coaggregation between Rhodococcus and Acinetobacter strains isolated from the food industry.

    Science.gov (United States)

    Møretrø, Trond; Sharifzadeh, Shahab; Langsrud, Solveig; Heir, Even; Rickard, Alexander H

    2015-07-01

    In this study, coaggregation interactions between Rhodococcus and Acinetobacter strains isolated from food-processing surfaces were characterized. Rhodococcus sp. strain MF3727 formed intrageneric coaggregates with Rhodococcus sp. strain MF3803 and intergeneric coaggregates with 2 strains of Acinetobacter calcoaceticus (MF3293, MF3627). Stronger coaggregation between A. calcoaceticus MF3727 and Rhodococcus sp. MF3293 was observed after growth in batch culture at 30 °C than at 20 °C, after growth in tryptic soy broth than in liquid R2A medium, and between cells in exponential and early stationary phases than cells in late stationary phase. The coaggregation ability of Rhodococcus sp. MF3727 was maintained even after heat and Proteinase K treatment, suggesting its ability to coaggregate was protein independent whereas the coaggregation determinants of the other strains involved proteinaceous cell-surface-associated polymers. Coaggregation was stable at pH 5-9. The mechanisms of coaggregation among Acinetobacter and Rhodococcus strains bare similarity to those displayed by coaggregating bacteria of oral and freshwater origin, with respect to binding between proteinaceous and nonproteinaceous determinants and the effect of environmental factors on coaggregation. Coaggregation may contribute to biofilm formation on industrial food surfaces, protecting bacteria against cleaning and disinfection.

  15. [Isolation, identification and lead adsorption study of lead-resistant Lactobacillus casei strains from feces of healthy newborns].

    Science.gov (United States)

    Shen, Wei; Yu, Qin-Fei; Wang, Yu-Hao; Zhang, Yi-Duo; Meng, Xiao-Jing; Fan, Hong-Ying

    2016-12-20

    To isolate and identify lead-resistant Lactobacillus casei strains with lead adsorption ability from the stool of healthy newborns as a new source of bacteria for developing lead-eliminating food products. MRS was used to isolate lead-resistant bacteria from the feces of 30 healthy and full-term neonates. A phylogenetic tree was constructed based on the morphological characteristics and 16S rRNA sequences of the isolated bacteria. Physiological and biochemical characterizations of the bacteria were performed according to the Berger's Systematic Bacteriology Handbook, followed by antimicrobial susceptibility test and acid-tolerant bile salt test. The adsorption capacity of Pb 2+ of the bacteria was determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Three strains of Lactobacillus casei were isolated, which were resistant to penicillin and ceftriaxone and could tolerate the exposure to 500 mg/L Pb 2+ . Acid-tolerant bile salt test showed that the bacteria were resistant to culture in the presence of artificial gastric juice (pH 2.0) for 3 h, and their survival rate reached 62.5% following exposure to 0.3% bile salt for 8 h. The bacteria showed a Pb 2+ adsorption rate of 90.4% at a low Pb 2+ concentration (1 mg/L) and of 86.27% at a high Pb 2+ concentration (50 mg/L). Three Lactobacillus casei strains lead adsorption ability were isolated from the feces of newborns. These bacterial strains provide a new solution to alleviate lead poisoning by probiotic dietary.

  16. Characterization of Trypanosoma cruzi Strains Isolated from Chronic Chagasic Patients, Triatomines and Opossums Naturally Infected from the State of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Cloé Duarte Fernandes

    1997-05-01

    Full Text Available Thirty-five Trypanosoma cruzi strains were isolated from chronic chagasic patients, triatomines and opossums from different municipalities of the State of Rio Grande do Sul. Parasites were characterized by means of mice infectivity, enzyme electrophoresis and randomly amplified polymorphic DNA (RAPD analysis. Twenty-nine strains were isolated from chagasic patients, 4 from triatomines (2 from Triatoma infestans and 2 from Panstrongylus megistus and 2 from opossums Didelphis albiventris. Thirty-three T. cruzi strains were of low and 2 strains of high virulence in mice. Both virulent strains were isolated from P. megistus. Isoenzyme analysis of the strains showed 3 different zymodemes. Eleven strains isolated from chagasic patients and 2 from D. albiventris were Z2. Eighteen strains from patients and 2 from T. infestans were ZB and 2 T. cruzi strains isolated from P. megistus were Z1. RAPD profiles obtained with 4 random primers showed a high genetic heterogeneity of the T. cruzi strains. Zymodeme 2 and ZB strains were the more polymorphic. A band sharing analysis of the RAPD profiles of Z2 and ZB strains using 3 primers, showed a very low percentage of shared bands, 20% among 13 ZB strains and 14% among 13 Z2 strains. According to the isoenzyme results, 3 T. cruzi populations were present in State of Rio Grande do Sul. Zymodeme 2 and ZB strains were found infecting man (domiciliar transmission cycle whereas Z1 strains were found infecting the sylvatic vector P. megistus

  17. Matrix Production, Pigment Synthesis, and Sporulation in a Marine Isolated Strain of Bacillus pumilus.

    Science.gov (United States)

    Di Luccia, Blanda; Riccio, Antonio; Vanacore, Adele; Baccigalupi, Loredana; Molinaro, Antonio; Ricca, Ezio

    2015-10-21

    The ability to produce an extracellular matrix and form multicellular communities is an adaptive behavior shared by many bacteria. In Bacillus subtilis, the model system for spore-forming bacteria, matrix production is one of the possible differentiation pathways that a cell can follow when vegetative growth is no longer feasible. While in B. subtilis the genetic system controlling matrix production has been studied in detail, it is still unclear whether other spore formers utilize similar mechanisms. We report that SF214, a pigmented strain of Bacillus pumilus isolated from the marine environment, can produce an extracellular matrix relying on orthologs of many of the genes known to be important for matrix synthesis in B. subtilis. We also report a characterization of the carbohydrates forming the extracellular matrix of strain SF214. The isolation and characterization of mutants altered in matrix synthesis, pigmentation, and spore formation suggest that in strain SF214 the three processes are strictly interconnected and regulated by a common molecular mechanism.

  18. Antibiotic Resistance Pattern of Staphylococcus aureus Strains Isolated from Personnel of Jahrom Hospitals in 2012

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    S Saadat

    2014-01-01

    Undo edits Methods: In this cross - sectional study, 397 of the anterior nasal samples of medical personnel and hospital services were collected by swab. The identification of S.aureus was determined by biochemical tests and microbiology, and the antibiotic resistances of isolates were determined by disk diffusion method for 13 antibiotics. In this method, the inhibition zone for methicillin-resistant strains was ≤ 10 mm the minimum inhibitory concentrations (MIC against antibiotic vancomycin, ticoplanin, linezolid and synercid were determined by E-test method. Results: In the present study, 11.3% of personals carried S. aureus in the nose. Among them, 90% were health care workers and 10% were health service workers. The most sensitivity was observed resistance to Ciprofloxacin, rifampin, linezolid and synercid (91.1%, but the lowest sensitivity was to penicillin (4.7%. of 9 MRSA strains, 1 strain was resistance to vancomycin and 2 strains were resistant to teicoplanin and linezolid. Conclusion: Because of S. aureus strains isolated from hospital staffs were resistant to most common antibiotics, identification and treatment of health care and health service workers can prevent nosocomial infections. Key words: Staphylococcu aureus carriers, hospital personnel, antibiotic resistance.

  19. Major clonal lineages in impetigo Staphylococcus aureus strains isolated in Czech and Slovak maternity hospitals.

    Science.gov (United States)

    Růžičková, Vladislava; Pantůček, Roman; Petráš, Petr; Machová, Ivana; Kostýlková, Karla; Doškař, Jiří

    2012-11-01

    One hundred and twenty-seven exfoliative toxin-producing (ET-positive) strains of Staphylococcus aureus collected in 23 Czech and one Slovak maternity hospitals from 1998 to 2011 were genotypically characterized by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE) profiling, spa gene polymorphism analysis, and ETA-converting prophage carriage, which resulted in the identification of 21 genotypes grouped into 4 clonal complexes (CC). Ninety-one isolates carried the eta gene alone whilst 12 isolates harboured only the etb gene. Two new, to date not defined, spa types (t6644 and t6645) and 2 novel sequence types (ST2194 and ST2195) were identified in the set of strains under study. The predominant CC121 occurred in 13 Czech hospitals. CC15, CC9, and ST88 (CC88) exclusively included eta gene-positive strains while the strains belonging to ST121 harboured the eta and/or etb genes. This study highlights not only significant genomic diversity among impetigo strains and the distribution of major genotypes disseminated in the Czech and Slovak maternity hospitals, but also reveals their impact in epidermolytic infections. Copyright © 2012 Elsevier GmbH. All rights reserved.

  20. Differentiation and distribution of potato virus Y strains isolated from tobacco in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Vorster, L L

    1986-01-01

    Four strains of potato virus Y (PVY) orginally isolated from tobacco in South Africa belonging to three different strain groups (PVY/sup N/, PVY/sup c/ and PVY/sup o/) were differentiated according to their effect on various tobacco cultivars. The results obtained in this study confirm previous reports which indicated that inoculation with PVY had a detrimental effect on the yield and quality of tobacco. The severity of the effects was generally related to the length of time that the virus was present in the host, with late infections having less effect than early infections. An important aspect that evolved from the present study is the differences in reactions of the various strains (necrotic to mild strains) of PVY on the tobacco cultivars tested. A direct correlation was evident between the virulence of the different PVY strains and the effect of O/sub 2/-uptake of the host. cDNA probes prepared from PVY-RNA are specific to RNA extracted from purified PVY suspensions as well as crude sap from tobacco plants infected with the PVY strains used in this study. Radioactive probes and /sup 32/Phosporus labelling were used in the DNA and RNA studies of PVY. A procedure described by Bar-Joseph, et al (1983) were used successfully for the isolation of viral double-stranded RNA from various tissues. However, from the results obtained in this study it is clear that this method is of little or no value for the detection and diagnosis of PVY strains.

  1. Mycobacterium eburneum sp. nov., a non-chromogenic, fast-growing strain isolated from sputum.

    Science.gov (United States)

    Nouioui, Imen; Carro, Lorena; Teramoto, Kanae; Igual, José M; Jando, Marlen; Del Carmen Montero-Calasanz, Maria; Sutcliffe, Iain; Sangal, Vartul; Goodfellow, Michael; Klenk, Hans-Peter

    2017-09-01

    A polyphasic study was undertaken to establish the taxonomic position of a non-chromogenic, rapidly growing Mycobacterium strain that had been isolated from sputum. The strain, CECT 8775T, has chemotaxonomic and cultural properties consistent with its classification in the genus Mycobacterium and was distinguished from the type strains of closely related mycobacterial species, notably from Mycobacterium paraense DSM 46749T, its nearest phylogenetic neighbour, based on 16S rRNA, hsp65 and rpoB gene sequence data. These organisms were also distinguished by a broad range of chemotaxonomic and phenotypic features and by a digital DNA-DNA relatedness value of 22.8 %. Consequently, the strain is considered to represent a novel species of Mycobacterium for which the name Mycobacterium eburneum sp. nov is proposed; the type strain is X82T (CECT 8775T=DSM 44358T).

  2. Strains of avian paramyxovirus type 1 of low pathogenicity for chickens isolated from poultry and wild birds in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Poul Henrik; Handberg, Kurt; Ahrens, Peter

    2004-01-01

    Twenty-one strains of avian paramyxovirus type 1 of low virulence for chickens were isolated in Denmark between 1996 and the beginning of 2003. The low virulence of the strains was demonstrated by sequencing the fusion (F) gene at the cleavage site motif and in some cases by determining the intra......Twenty-one strains of avian paramyxovirus type 1 of low virulence for chickens were isolated in Denmark between 1996 and the beginning of 2003. The low virulence of the strains was demonstrated by sequencing the fusion (F) gene at the cleavage site motif and in some cases by determining...

  3. Haemolytic Escherichia coli isolated from dogs with diarrhea have characteristics of both uropathogenic and necrotoxigenic strains

    NARCIS (Netherlands)

    Starxix, M.; Johnson, J.R.; Stell, A.L.; Goot, van der J.A.; Hendriks, H.G.; Vorstenbosch, van C.; Dijk, van L.; Gaastra, W.

    2002-01-01

    Twenty-four haemolytic Escherichia coli strains were isolated from dogs with diarrhea. The strains were serotyped and analysed by polymerase chain reaction (PCR) for genes encoding virulence factors associated with E. coli that cause diarrhea in animals. Adhesion antigen production was deduced from

  4. Genotypic and phenotypic diversity of Lactobacillus rhamnosus clinical isolates, their comparison with strain GG and their recognition by complement system.

    Science.gov (United States)

    Nissilä, Eija; Douillard, François P; Ritari, Jarmo; Paulin, Lars; Järvinen, Hanna M; Rasinkangas, Pia; Haapasalo, Karita; Meri, Seppo; Jarva, Hanna; de Vos, Willem M

    2017-01-01

    Lactobacillus rhamnosus strains are ubiquitous in fermented foods, and in the human body where they are commensals naturally present in the normal microbiota composition of gut, vagina and skin. However, in some cases, Lactobacillus spp. have been implicated in bacteremia. The aim of the study was to examine the genomic and immunological properties of 16 clinical blood isolates of L. rhamnosus and to compare them to the well-studied L. rhamnosus probiotic strain GG. Blood cultures from bacteremic patients were collected at the Helsinki University Hospital laboratory in 2005-2011 and L. rhamnosus strains were isolated and characterized by genomic sequencing. The capacity of the L. rhamnosus strains to activate serum complement was studied using immunological assays for complement factor C3a and the terminal pathway complement complex (TCC). Binding of complement regulators factor H and C4bp was also determined using radioligand assays. Furthermore, the isolated strains were evaluated for their ability to aggregate platelets and to form biofilms in vitro. Genomic comparison between the clinical L. rhamnosus strains showed them to be clearly different from L. rhamnosus GG and to cluster in two distinct lineages. All L. rhamnosus strains activated complement in serum and none of them bound complement regulators. Four out of 16 clinical blood isolates induced platelet aggregation and/or formed more biofilms than L. rhamnosus GG, which did not display platelet aggregation activity nor showed strong biofilm formation. These findings suggest that clinical L. rhamnosus isolates show considerable heterogeneity but are clearly different from L. rhamnosus GG at the genomic level. All L. rhamnosus strains are still normally recognized by the human complement system.

  5. Description of two Enterococcus strains isolated from traditional Peruvian artisanal-produced cheeses with a bacteriocin-like inhibitory activity

    Directory of Open Access Journals (Sweden)

    Aguilar Galvez A.

    2009-01-01

    Full Text Available The aim of this work was to isolate and to characterize strains of lactic acid bacteria (LAB with bacteriocin-like inhibitory activity from 27 traditional cheeses artisanal-produced obtained from different Peruvian regions. Twenty Gram+ and catalasenegative strains among 2,277 isolates exhibited bacteriocin-like inhibitory activity against Listeria monocytogenes CWBIB2232 as target strain. No change in inhibitory activity was observed after organic acid neutralization and treatment with catalase of the cell-free supernatant (CFS. The proteinic nature of the antimicrobial activity was confirmed for the twenty LAB strains by proteolytic digestion of the CFS. Two strains, CWBI-B1431 and CWBI-B1430, with the best antimicrobial activity were selected for further researches. These strains were taxonomically identified by phenotypic and genotypic analyses as Enterococcus mundtii (CWBI-B1431 and Enterococcus faecium (CWBI-B1430. The two strains were sensitive to vancomycin (MIC 2 μg.ml-1 and showed absence of haemolysis.

  6. In Vitro Characterization of Lactobacillus Strains Isolated from Fruit Processing By-Products as Potential Probiotics.

    Science.gov (United States)

    de Albuquerque, Thatyane Mariano Rodrigues; Garcia, Estefânia Fernandes; de Oliveira Araújo, Amanda; Magnani, Marciane; Saarela, Maria; de Souza, Evandro Leite

    2017-08-23

    Nine wild Lactobacillus strains, namely Lactobacillus plantarum 53, Lactobacillus fermentum 56, L. fermentum 60, Lactobacillus paracasei 106, L. fermentum 250, L. fermentum 263, L. fermentum 139, L. fermentum 141, and L. fermentum 296, isolated from fruit processing by-products were evaluated in vitro for a series of safety, physiological functionality, and technological properties that could enable their use as probiotics. Considering the safety aspects, the resistance to antibiotics varied among the examined strains, and none of the strains presented hemolytic and mucinolytic activity. Regarding the physiological functionality properties, none of the strains were able to deconjugate bile salts; all of them presented low to moderate cell hydrophobicity and were able to autoaggregate, coaggregate with Listeria monocytogenes and Escherichia coli, and antagonize pathogenic bacteria. Exposure to pH 2 sharply decreased the survival of the examined strains after 1- or 2-h exposure; variable decreases were noted after 3-h exposure to pH 3. Overall, exposure to pH 5 and to bile salts (0.15, 0.3, and 1%) did not decrease the strains' survival. Examined strains presented better ability to survive from the exposure to simulated gastrointestinal conditions in laboratorial media and milk than in grape juice. Considering the technological properties, all the strains were positive for proteolytic activity and EPS and diacetyl production, and most of them had good tolerance to 1-4% NaCl. These results indicate that wild Lactobacillus strains isolated from fruit processing by-products could present performance compatible with probiotic properties and technological features that enable the development of probiotic foods with distinct characteristics.

  7. Molecular characterization of Acanthamoeba strains isolated from domestic dogs in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Valladares, María; Reyes-Batlle, María; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Dorta-Gorrín, Alexis; Wagner, Carolina; Martínez-Carretero, Enrique; Piñero, José E; Valladares, Basilio; Lorenzo-Morales, Jacob

    2015-06-01

    The present study describes two cases of Acanthamoeba infections (keratitis and ascites/peritonitis) in small breed domestic dogs in Tenerife, Canary Islands, Spain. In both cases, amoebic trophozoites were observed under the inverted microscope and isolated from the infected tissues and/or fluids, without detecting the presence of other viral, fungal or bacterial pathogens. Amoebae were isolated using 2 % non-nutrient agar plates and axenified for further biochemical and molecular analyses. Osmotolerance and thermotolerance assays revealed that both isolates were able to grow up to 37 °C and 1 M of mannitol and were thus considered as potentially pathogenic. Moreover, the strains were classified as highly cytotoxic as they cause more than 75 % of toxicity when incubated with two eukaryotic cell lines. In order to classify the strains at the molecular level, the diagnostic fragment 3 (DF3) region of the 18S rDNA of Acanthamoeba was amplified and sequenced, revealing that both isolates belonged to genotype T4. In both cases, owners of the animals did not allow any further studies or follow-up and therefore the current status of these animals is unknown. Furthermore, the isolation of these pathogenic amoebae should raise awareness with the veterinary community locally and worldwide.

  8. Genomic differentiation among two strains of the PS1 clade isolated from geographically separated marine habitats

    KAUST Repository

    Jimenez Infante, Francy M.

    2014-05-22

    Using dilution-to-extinction cultivation, we isolated a strain affiliated with the PS1 clade from surface waters of the Red Sea. Strain RS24 represents the second isolate of this group of marine Alphaproteobacteria after IMCC14465 that was isolated from the East (Japan) Sea. The PS1 clade is a sister group to the OCS116 clade, together forming a putatively novel order closely related to Rhizobiales. While most genomic features and most of the genetic content are conserved between RS24 and IMCC14465, their average nucleotide identity (ANI) is < 81%, suggesting two distinct species of the PS1 clade. Next to encoding two different variants of proteorhodopsin genes, they also harbor several unique genomic islands that contain genes related to degradation of aromatic compounds in IMCC14465 and in polymer degradation in RS24, possibly reflecting the physicochemical differences in the environment they were isolated from. No clear differences in abundance of the genomic content of either strain could be found in fragment recruitment analyses using different metagenomic datasets, in which both genomes were detectable albeit as minor part of the communities. The comparative genomic analysis of both isolates of the PS1 clade and the fragment recruitment analysis provide first insights into the ecology of this group. © 2014 Federation of European Microbiological Societies.

  9. Complete genome sequence of Bifidobacterium breve CECT 7263, a strain isolated from human milk.

    Science.gov (United States)

    Jiménez, Esther; Villar-Tajadura, M Antonia; Marín, María; Fontecha, Javier; Requena, Teresa; Arroyo, Rebeca; Fernández, Leónides; Rodríguez, Juan M

    2012-07-01

    Bifidobacterium breve is an actinobacterium frequently isolated from colonic microbiota of breastfeeding babies. Here, we report the complete and annotated genome sequence of a B. breve strain isolated from human milk, B. breve CECT 7263. The genome sequence will provide new insights into the biology of this potential probiotic organism and will allow the characterization of genes related to beneficial properties.

  10. Physiology of Saccharomyces cerevisiae strains isolated from Brazilian biomes: new insights into biodiversity and industrial applications

    DEFF Research Database (Denmark)

    Beato, Felipe B.; Bergdahl, Basti; Rosa, Carlos A.

    2016-01-01

    Fourteen indigenous Saccharomyces cerevisiae strains isolated from the barks of three tree species located in the Atlantic Rain Forest and Cerrado biomes in Brazil were genetically and physiologically compared to laboratory strains and to strains from the Brazilian fuel ethanol industry. Although...

  11. Prevalence and Characteristics of Streptococcus canis Strains Isolated from Dogs and Cats

    Directory of Open Access Journals (Sweden)

    P. Lysková

    2007-01-01

    Full Text Available To determine the prevalence of Streptococcus canis in dogs and cats, a total of 926 swabs were examined bacteriologically in the period from 2003 to 2005. Eighty-six isolates obtained from various anatomical locations were further characterized for their phenotypic properties. The most frequently isolated biotype produced phosphatase, leucine amidopeptidase, arginine dihydrolase, alpha-D- and beta-D-galactosidase and fermented lactose and ribose. Additional identification by species-specific amplification of the 16S-23S rRNA intergenic spacer region was consistent with S. canis. All isolates were susceptible to penicillin G and ampicillin. The least effective antimicrobial agent was found to be tetracycline (only 33.8% of susceptible strains.

  12. Probiotic Potential of Lactobacillus Strains with Antifungal Activity Isolated from Animal Manure.

    Science.gov (United States)

    Ilavenil, Soundharrajan; Park, Hyung Soo; Vijayakumar, Mayakrishnan; Arasu, Mariadhas Valan; Kim, Da Hye; Ravikumar, Sivanesan; Choi, Ki Choon

    2015-01-01

    The aim of the study was to isolate and characterize the lactic acid bacteria (LAB) from animal manure. Among the thirty LAB strains, four strains, namely, KCC-25, KCC-26, KCC-27, and KCC-28, showed good cell growth and antifungal activity and were selected for further characterization. Biochemical and physiology properties of strains confirmed that the strains are related to the Lactobacillus sp.; further, the 16S rRNA sequencing confirmed 99.99% sequence similarity towards Lactobacillus plantarum. The strains exhibited susceptibility against commonly used antibiotics with negative hemolytic property. Strains KCC-25, KCC-26, KCC-27, and KCC-28 showed strong antifungal activity against Aspergillus fumigatus, Penicillium chrysogenum, Penicillium roqueforti, Botrytis elliptica, and Fusarium oxysporum, respectively. Fermentation studies noted that the strains were able to produce significant amount of lactic, acetic, and succinic acids. Further, the production of extracellular proteolytic and glycolytic enzymes, survival under low pH, bile salts, and gastric juice together with positive bile salt hydrolase (Bsh) activity, cholesterol lowering, cell surface hydrophobicity, and aggregation properties were the strains advantages. Thus, KCC-25, KCC-26, KCC-27, and KCC-28 could have the survival ability in the harsh condition of the digestive system in the gastrointestinal tract. In conclusion, novel L. plantarum KCC-25, KCC-26, KCC-27, and KCC-28 could be considered as potential antimicrobial probiotic strains.

  13. Probiotic Potential of Lactobacillus Strains with Antifungal Activity Isolated from Animal Manure

    Directory of Open Access Journals (Sweden)

    Soundharrajan Ilavenil

    2015-01-01

    Full Text Available The aim of the study was to isolate and characterize the lactic acid bacteria (LAB from animal manure. Among the thirty LAB strains, four strains, namely, KCC-25, KCC-26, KCC-27, and KCC-28, showed good cell growth and antifungal activity and were selected for further characterization. Biochemical and physiology properties of strains confirmed that the strains are related to the Lactobacillus sp.; further, the 16S rRNA sequencing confirmed 99.99% sequence similarity towards Lactobacillus plantarum. The strains exhibited susceptibility against commonly used antibiotics with negative hemolytic property. Strains KCC-25, KCC-26, KCC-27, and KCC-28 showed strong antifungal activity against Aspergillus fumigatus, Penicillium chrysogenum, Penicillium roqueforti, Botrytis elliptica, and Fusarium oxysporum, respectively. Fermentation studies noted that the strains were able to produce significant amount of lactic, acetic, and succinic acids. Further, the production of extracellular proteolytic and glycolytic enzymes, survival under low pH, bile salts, and gastric juice together with positive bile salt hydrolase (Bsh activity, cholesterol lowering, cell surface hydrophobicity, and aggregation properties were the strains advantages. Thus, KCC-25, KCC-26, KCC-27, and KCC-28 could have the survival ability in the harsh condition of the digestive system in the gastrointestinal tract. In conclusion, novel L. plantarum KCC-25, KCC-26, KCC-27, and KCC-28 could be considered as potential antimicrobial probiotic strains.

  14. Antibacterial and Antioxidant Activities of Novel Actinobacteria Strain Isolated from Gulf of Khambhat, Gujarat.

    Science.gov (United States)

    Dholakiya, Riddhi N; Kumar, Raghawendra; Mishra, Avinash; Mody, Kalpana H; Jha, Bhavanath

    2017-01-01

    Bacterial secondary metabolites possess a wide range of biologically active compounds including antibacterial and antioxidants. In this study, a Gram-positive novel marine Actinobacteria was isolated from sea sediment which showed 84% 16S rRNA gene sequence (KT588655) similarity with Streptomyces variabilis (EU841661) and designated as Streptomyces variabilis RD-5. The genus Streptomyces is considered as a promising source of bioactive secondary metabolites. The isolated novel bacterial strain was characterized by antibacterial characteristics and antioxidant activities. The BIOLOG based analysis suggested that S. variabilis RD-5 utilized a wide range of substrates compared to the reference strain. The result is further supported by statistical analysis such as AWCD (average well color development), heat-map and PCA (principal component analysis). The whole cell fatty acid profiling showed the dominance of iso/anteiso branched C15-C17 long chain fatty acids. The identified strain S. variabilis RD-5 exhibited a broad spectrum of antibacterial activities for the Gram-negative bacteria ( Escherichia coli NCIM 2065, Shigella boydii NCIM, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas sp. NCIM 2200 and Salmonella enteritidis NCIM), and Gram-positive bacteria ( Bacillus subtilis NCIM 2920 and Staphylococcus aureus MTCC 96). Extract of S. variabilis strain RD-5 showed 82.86 and 89% of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and metal chelating activity, respectively, at 5.0 mg/mL. While H 2 O 2 scavenging activity was 74.5% at 0.05 mg/mL concentration. Furthermore, polyketide synthases (PKSs types I and II), an enzyme complex that produces polyketides, the encoding gene(s) detected in the strain RD-5 which may probably involve for the synthesis of antibacterial compound(s). In conclusion, a novel bacterial strain of Actinobacteria , isolated from the unexplored sea sediment of Alang, Gulf of Khambhat (Gujarat), India showed promising

  15. Antibacterial and Antioxidant Activities of Novel Actinobacteria Strain Isolated from Gulf of Khambhat, Gujarat

    Directory of Open Access Journals (Sweden)

    Riddhi N. Dholakiya

    2017-12-01

    Full Text Available Bacterial secondary metabolites possess a wide range of biologically active compounds including antibacterial and antioxidants. In this study, a Gram-positive novel marine Actinobacteria was isolated from sea sediment which showed 84% 16S rRNA gene sequence (KT588655 similarity with Streptomyces variabilis (EU841661 and designated as Streptomyces variabilis RD-5. The genus Streptomyces is considered as a promising source of bioactive secondary metabolites. The isolated novel bacterial strain was characterized by antibacterial characteristics and antioxidant activities. The BIOLOG based analysis suggested that S. variabilis RD-5 utilized a wide range of substrates compared to the reference strain. The result is further supported by statistical analysis such as AWCD (average well color development, heat-map and PCA (principal component analysis. The whole cell fatty acid profiling showed the dominance of iso/anteiso branched C15–C17 long chain fatty acids. The identified strain S. variabilis RD-5 exhibited a broad spectrum of antibacterial activities for the Gram-negative bacteria (Escherichia coli NCIM 2065, Shigella boydii NCIM, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas sp. NCIM 2200 and Salmonella enteritidis NCIM, and Gram-positive bacteria (Bacillus subtilis NCIM 2920 and Staphylococcus aureus MTCC 96. Extract of S. variabilis strain RD-5 showed 82.86 and 89% of 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical scavenging and metal chelating activity, respectively, at 5.0 mg/mL. While H2O2 scavenging activity was 74.5% at 0.05 mg/mL concentration. Furthermore, polyketide synthases (PKSs types I and II, an enzyme complex that produces polyketides, the encoding gene(s detected in the strain RD-5 which may probably involve for the synthesis of antibacterial compound(s. In conclusion, a novel bacterial strain of Actinobacteria, isolated from the unexplored sea sediment of Alang, Gulf of Khambhat (Gujarat, India showed promising

  16. Antibacterial and Antioxidant Activities of Novel Actinobacteria Strain Isolated from Gulf of Khambhat, Gujarat

    Science.gov (United States)

    Dholakiya, Riddhi N.; Kumar, Raghawendra; Mishra, Avinash; Mody, Kalpana H.; Jha, Bhavanath

    2017-01-01

    Bacterial secondary metabolites possess a wide range of biologically active compounds including antibacterial and antioxidants. In this study, a Gram-positive novel marine Actinobacteria was isolated from sea sediment which showed 84% 16S rRNA gene sequence (KT588655) similarity with Streptomyces variabilis (EU841661) and designated as Streptomyces variabilis RD-5. The genus Streptomyces is considered as a promising source of bioactive secondary metabolites. The isolated novel bacterial strain was characterized by antibacterial characteristics and antioxidant activities. The BIOLOG based analysis suggested that S. variabilis RD-5 utilized a wide range of substrates compared to the reference strain. The result is further supported by statistical analysis such as AWCD (average well color development), heat-map and PCA (principal component analysis). The whole cell fatty acid profiling showed the dominance of iso/anteiso branched C15–C17 long chain fatty acids. The identified strain S. variabilis RD-5 exhibited a broad spectrum of antibacterial activities for the Gram-negative bacteria (Escherichia coli NCIM 2065, Shigella boydii NCIM, Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas sp. NCIM 2200 and Salmonella enteritidis NCIM), and Gram-positive bacteria (Bacillus subtilis NCIM 2920 and Staphylococcus aureus MTCC 96). Extract of S. variabilis strain RD-5 showed 82.86 and 89% of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and metal chelating activity, respectively, at 5.0 mg/mL. While H2O2 scavenging activity was 74.5% at 0.05 mg/mL concentration. Furthermore, polyketide synthases (PKSs types I and II), an enzyme complex that produces polyketides, the encoding gene(s) detected in the strain RD-5 which may probably involve for the synthesis of antibacterial compound(s). In conclusion, a novel bacterial strain of Actinobacteria, isolated from the unexplored sea sediment of Alang, Gulf of Khambhat (Gujarat), India showed promising

  17. Isolation and characterization of Alicycliphilus denitrificans strain BC, which grows on benzene with chlorate as the electron acceptor

    NARCIS (Netherlands)

    Weelink, S.A.B.; Tan, N.C.G.; Broeke, H. ten; Kieboom, C. van den; Doesburg, W. van; Langenhoff, A.A.M.; Gerritse, J.; Junca, H.; Stams, A.J.M.

    2008-01-01

    A bacterium, strain BC, was isolated from a benzene-degrading chlorate-reducing enrichment culture. Strain BC degrades benzene in conjunction with chlorate reduction. Cells of strain BC are short rods that are 0.6 μm wide and 1 to 2 μm long, are motile, and stain gram negative. Strain BC grows on

  18. Identification of strains with phenotypes similar to those of Staphylococcus aureus isolated from table chicken eggs using MALDI-TOF MS and genotyping methods

    Directory of Open Access Journals (Sweden)

    Marek Agnieszka

    2015-06-01

    Full Text Available The aim of the study was to identify the affinity of 10 Staphylococcus strains isolated from table chicken eggs to specific species. Preliminary analysis performed by API ID32 Staph test identified these strains as S. aureus, but they exhibited a negative reaction in the tube coagulase test. Thus, the analysed strains were initially characterised as Staphylococcus aureus-like (SAL. Further characterisation was performed by genotypic methods, using restriction fragment length polymorphism (RFLP of the coagulase gene (coa and sequencing of the gene rpoB. An attempt was also made to identify the isolated Staphylococcus strains by MALDI-TOF mass spectrometry. The results indicated that none of the strains tested belonged to the species S. aureus. The rpoB sequences of five isolates showed the highest sequence similarity to S. haemolyticus, three isolates to S. chromogenes, and one isolate to S. epidermidis. One strain (SAL4 remained unidentified in this analysis. The results obtained using mass spectrometry were comparable to those based on gene sequence analysis. Strain SAL4, which could not be identified by sequencing, was identified by MALDI-TOF as Staphylococcus chromogenes.

  19. The first pathogenic Yersinia enterocolitica bioserotype 4/O:3 strain isolated from a hunted wild boar (Sus scrofa) in Poland.

    Science.gov (United States)

    Bancerz-Kisiel, A; Platt-Samoraj, A; Szczerba-Turek, A; Syczyło, K; Szweda, W

    2015-10-01

    The objective of this study was to identify the bioserotypes and virulence markers of Yersinia enterocolitica strains isolated from wild boars in Poland. Bacteriological examination of 302 rectal swabs from 151 wild boars resulted in the isolation of 40 Y. enterocolitica strains. The majority of the examined strains (n = 30), belonged to bioserotype 1A/NI. The presence of individual Y. enterocolitica strains belonging to bioserotypes 1B/NI (3), 1A/O:8 (2), 1A/O:27 (2), 2/NI (1), 2/O:9 (1) and 4/O:3 (1) was also demonstrated. Amplicons corresponding to ail and ystA genes were observed only in one Y. enterocolitica strain--bioserotype 4/O:3. The ail and ystB gene amplicons were noted in 11 Y. enterocolitica biotype 1A strains, although single amplicons of ystB gene were found in 28 of the tested samples. In four out of eight cases when two Y. enterocolitica strains were isolated from the same animal, the strains differed in biotype, serotype or virulence markers. The European population of wild boars continues to grow and spread to new areas, therefore, wild boars harbouring potentially pathogenic Y. enterocolitica 4/O:3 strains pose a challenge to public health.

  20. In vitro biofilm formation by methicillin susceptible and resistant Staphylococcus aureus strains isolated from cystic fibrosis patients

    Directory of Open Access Journals (Sweden)

    Antonietta Lambiase

    2008-12-01

    Full Text Available Staphylococcus aureus is one of the most common pathogens isolated from respiratory tracts of Cystic Fibrosis patients (CF. The infection by this pathogen starts in early infancy, often preceding chronic infections by Pseudomonas aeruginosa. The infection and colonization by methicillin-resistant Staphylococcus aureus (MRSA are, by then, events very frequent among CF patients and this bacterial isolation leads to complications in therapeutic management because of the limited treatment options. Strains of Staphylococcus aureus are able to produce biofilms on natural or synthetic surfaces. Biofilms are sophisticated communities of matrix-encased bacteria and infections by biofilm-producing bacteria are particularly problematic because sessile bacteria can often withstand host immune responses and are generally much more tolerant to antibiotics. The first aim of this work is to evaluate the ability of MRSA strains isolated from respiratory secretions of CF patients to develop biofilms in comparison with methicillin-sensitive Staphylococcus aureus (MSSA strains obtained from respiratory secretions of CF patients.Therefore, our second aim is to evaluate the environmental influence on this ability. To evaluate the development of biofilm on solid matrix and the possible environmental influence,we applied the method described by Christensen et al. We found that a significantly higher number of MRSA strains were biofilm positive compared with MSSA strains (p<0.05.The presence of glucose did not influence the ability to form biofilm in our MRSA strains (p=0.165. MSSA strains are not strong biofilm-producers, but, when grown in TSB added with 0.25% glucose, the number of biofilm-forming strains increases, as expected. These data suggest a possible association between methicillin-resistance and biofilm formation.

  1. High-resolution melt PCR analysis for rapid identification of Chlamydia abortus live vaccine strain 1B among C. abortus strains and field isolates.

    Science.gov (United States)

    Vorimore, Fabien; Cavanna, Noémie; Vicari, Nadia; Magnino, Simone; Willems, Hermann; Rodolakis, Annie; Siarkou, Victoria I; Laroucau, Karine

    2012-09-01

    We describe a novel high-resolution melt assay that clearly differentiates Chlamydia abortus live vaccine strain 1B from field C. abortus strains and field wild-type isolates based on previously described single nucleotide polymorphisms. This modern genotyping technique is inexpensive, easy to use, and less time-consuming than PCR-RFLP. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Selection of Leuconostoc strains isolated from artisanal Serrano Catarinense cheese for use as adjuncts in cheese manufacture.

    Science.gov (United States)

    Seixas, Felipe Nael; Rios, Edson Antônio; Martinez de Oliveira, André Luiz; Beloti, Vanerli; Poveda, Justa Maria

    2018-08-01

    Serrano Catarinense cheese is a raw bovine milk cheese produced in the region of Santa Catarina, Brazil. Twelve representative strains of Leuconostoc isolated from 20 samples of this artisanal cheese were selected and submitted for evaluation of the acidifying, proteolytic, autolytic, aminopeptidase and lipolytic activities, NaCl and acid resistance, production of dextran and biogenic amines and antimicrobial activity. The aim was to genetically and technologically characterize the Leuconostoc strains in order to use them in mixed starter cultures for cheese manufacture. Leuconostoc mesenteroides subsp. mesenteroides was the species that accounted for the largest proportion of isolates of Leuconostoc genus. Two leuconostoc isolates stood out in the acidifying activity, with reduction in pH of 1.12 and 1.04 units. The isolates showed low proteolytic and autolytic activity. Most of the isolates were dextran producers, presented good resistance to the salt and pH conditions of the cheese and showed antimicrobial activity against cheese pathogen bacteria, and none of them produced biogenic amines. These results allowed the selection of five strains (UEL 04, UEL 12, UEL 18, UEL 21 and UEL 28) as good candidates for use as adjunct cultures for cheese manufacture. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  3. Antibiotic resistance patterns of coagulase-negative staphylococcus strains isolated from blood cultures of septicemic patients in Turkey.

    Science.gov (United States)

    Koksal, F; Yasar, H; Samasti, M

    2009-01-01

    The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial bacteremia. A total of 200 CoNS strains were isolated from blood samples of patients with true bacteremia who were hospitalized in intensive care units and in other departments of Istanbul University Cerrahpasa Medical Hospital between 1999 and 2006. Among 200 CoNS isolates, Staphylococcus epidermidis was the most prevalent species (87) followed by Staphylococcus haemolyticus (23), Staphylococcus hominis (19), Staphylococcus lugdunensis (18), Staphylococcus capitis (15), Staphylococcus xylosus (10), Staphylococcus warneri (8), Staphylococcus saprophyticus (5), Staphylococcus lentus (5), Staphylococcus simulans (4), Staphylococcus chromogenes (3), Staphylococcus cohnii (1), Staphylococcus schleiferi (1), and Staphylococcus auricularis (1). Resistance to methicillin was detected in 67.5% of CoNS isolates. Methicillin-resistant CoNS strains were determined to be more resistant to antibiotics than methicillin-susceptible CoNS strains. Resistance rates of methicillin-resistant and methicillin-susceptible CoNS strains to the antibacterial agents, respectively, were as follows: gentamicin 90% and 17%, erythromycin 80% and 37%, clindamycin 72% and 18%, trimethoprim-sulfamethoxazole 68% and 38%, ciprofloxacin 67% and 23%, tetracycline 60% and 45%, chloramphenicol 56% and 13% and fusidic acid 25% and 15%. None of the strains were resistant to vancomycin and teicoplanin. Slime production was detected in 86 of 200 CoNS strains. Resistance to methicillin was found in 81% of slime-positive and in 57% of slime-negative strains. Our results indicated that there is a high level of resistance to widely used agents in causative methicillin-resistant CoNS strains. However fusidic acid has the smallest resistance ratio, with the exception of glycopeptides. Additionally, most S. epidermidis strains were slime

  4. Investigation of Antibacterial Properties of Yeast Strains Isolated from Iranian Richal and Traditional Dairy Products in Armenia

    Directory of Open Access Journals (Sweden)

    F Karimpour

    2016-09-01

    Full Text Available Background & aim:The use of bio preservative or strains as sources are interesting for food bioprocessing technologist,   and is one of the latest methods to increase the shelf life of food by the health authorities . The present study aimed to investigate the antibacterial activity of supernatants of yeasts isolated from Richal as a traditional dairy product and fermented dairy products in Armenia. Methods: In the present experimental study, the purified supernatant of 77 strains of Armenian yeast products and 12 strains from Iranian Richal were isolated. The purified supernatant were tested against three strains as food spoilages bacteria includes: B. subtilis 17-89, B. Thuringensis17-89, S.typhimuium G-38 , on 3media in 2 condition as aerobic and anaerobic. The inhibition zone of the supernatant were measured   and reported as antibacterial activity. Data were analyzed using statistical tests. Result: A total of 89 strains of yeasts, three species of Rachel and 9 strains of Armenian products (13.5% percent had demonstrated antibacterial activity. T86 strains of Armenian yeasts and FA1 (25 of Rachel had shown more ZOI and antibacterial activity on three media at both aerobic and anaerobic conditions. Comparing the mean of ZOI upon three corruption factors, Rachel strains were significantly different (p <0.05. The highest and lowest effect was observed on Bacillus subtilis effect and Salmonella typhimurium respectively. Conclusion: The results indicated that the yeast strains isolated in anaerobic and aerobic conditions on spoilage bacteria had antibacterial activity effect. Thus, it could be concluded that adding the yeast or its supernatant to food as a bio preservative, may introduce a operative product to the food industry.

  5. Isolation and identification of new lactobacilli from goatling stomach and investigation of reuterin production in Lactobacillus reuteri strains.

    Science.gov (United States)

    Kiňová Sepová, Hana; Bilková, Andrea

    2013-01-01

    Five new strains of lactobacilli isolated from goatling's stomach were identified by molecular-biological approaches. Profiles of fermentable saccharides, Gram staining, and cell morphology were also determined. They were identified as Lactobacillus reuteri (strains KO4b, KO4m, KO5) and as Lactobacillus plantarum (strains KG1z, KG4). In DNA samples of all newly isolated L. reuteri strains as well as in L. reuteri E (Lreu E; originated from lamb), the part of gldC gene, coding large subunit of glycerol dehydratase, that is necessary for 3-hydroxypropionaldehyde (3-HPA; reuterin) production, was amplified using two designed primer sets. However, the 3-HPA production was revealed only in the strain Lreu E. It produced five- or ten-fold lower amount of 3-HPA in comparison with probiotic L. reuteri ATCC 55730 in aerobic or anaerobic conditions, respectively. Moreover, Lreu E completely lost its production ability after ca. five passages in MRS medium. The co-incubation of Lreu E, but not other L. reuteri isolates, with Escherichia coli re-induced 3-HPA production. In the case of L. reuteri ATCC 55730, the 3-HPA production increased more than four times after co-incubation with E. coli.

  6. Screening of Probiotic Activities of Lactobacilli Strains Isolated from Traditional Tibetan Qula, A Raw Yak Milk Cheese.

    Science.gov (United States)

    Zhang, Bei; Wang, Yanping; Tan, Zhongfang; Li, Zongwei; Jiao, Zhen; Huang, Qunce

    2016-10-01

    In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42%) had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (pstrains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin) in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%), Lactobacillus plantarum 1086-1 (82%), Lactobacillus casei 1089 (81%), Lactobacillus casei 1138 (79%), Lactobacillus buchneri 1059 (78%), Lactobacillus plantarum1141 (75%), and Lactobacillus plantarum 1197 (71%). Together, these results suggest

  7. Isolation and characterization of Bacillus thuringiensis strains active against Elasmopalpus lignosellus (Zeller, 1848 (Lepidoptera, Pyralidae

    Directory of Open Access Journals (Sweden)

    Janaina Zorzetti

    2017-08-01

    Full Text Available Elasmopalpus lignosellus (Zeller, 1848 (Lepidoptera, Pyralidae is an insect pest of 60 economically important crops, including sugarcane, wheat, soybean, rice, beans, sorghum, peanuts, and cotton. The aim of this work was to select and characterize Bacillus thuringiensis isolates with insecticidal activity against E. Lignosellus that could be used as an alternative method of control. Selective bioassays were done to evaluate the toxicity of 47 isolates against first instar larvae of E. lignosellus. For the most toxic bacterial strains, the lethal concentration (LC50 was estimated and morphological, biochemical and molecular methods were used to characterize the isolates. Among the 47 isolates tested, 12 caused mortality above 85% and showed LC50 values from 0.038E+8 to 0.855E+8 spores mL-1. Isolates BR83, BR145, BR09, BR78, S1534, and S1302 had the lowest LC50 values and did not differ from the standard HD-1 strain; the exception was BR83.The protein profiles produced bands with molecular masses of 60-130 kDa. The genes cry1, cry2, cry3, and cry11 were identified in the molecular characterization. The morphological analysis identified three different crystal inclusions: bipyramidal, spherical and cuboidal. Among the tested isolates, 12 isolates have potential for biotechnological control of E. Lignosellus by development of new biopesticides or genetically modified plants.

  8. THE STUDY OF ANTIBIOTIC- AND FAGOSENSITIVITY OF NOSOCOMIAL STRAINS BACTERIA ISOLATED FROM TRANSPLANTED PATIENTS

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    N. I. Gabrielan

    2011-01-01

    Full Text Available Antibiotic and fagosensitivity most etiologically important nosocomial strains of bacteria – Pseudomonas aeru- ginosa, Klebsiella pneumoniae, E. coli, Proteus spp., Staphylococcus spp. were studied. Multiple drug-resistant bacteria as gram-positive and gram-negative, isolated from 8 substrates, had been demonstrated. With regard to the sensitivity of Pseudomonas aeruginosa >40% was observed in 40–50% of the strains to aminoglycosides – aztreonam, amikacin, netilmicin, and only 23–25% of the strains – to gentamicin and levofloxacin (an average of antibiotic susceptibility was 27%. All strains of ESBL Klebsiella drew up and were sensitive only to imipenem, meropenem and aminoglycosides. Specific phages lysed 43–48% of the strains Pseudomonas aeruginosa and Klebsiella pneumoniae, E. coli, Pro- teus spp., multidrug resistant strains of Staphylococcus spp. It is proposed to introduce the use of phages in clinical practice. 

  9. Single nucleotide polymorphism analysis of the enterocin P structural gene of Enterococcus faecium strains isolated from nonfermented animal foods.

    Science.gov (United States)

    Arlindo, Samuel; Calo, Pilar; Franco, Carlos; Prado, Marta; Cepeda, Alberto; Barros-Velázquez, Jorge

    2006-12-01

    The bacteriocins produced by two lactic acid bacteria isolated from nonfermented fresh meat and fish, respectively, and exhibiting a remarkable antilisterial activity, were characterized. Bacteriocinogenic strains were identified as Enterococcus faecium and the maximum bacteriocin production by both strains was detected in the stationary phase of growth. The activity against Listeria monocytogenes was maintained in pH range of 3-7 and was stable in both strains after heating at 100 or 121 degrees C. The genes coding for enterocin P were detected, isolated, and sequenced in both E. faecium strains. They exhibited DNA/DNA homology in the 87.1-97.2% range with respect to the other four enterocin P genes reported so far. Three single nucleotide polymorphism events, silent at the amino acid level, were detected at nucleotide positions 45 (G/A), 75 (A/G), and 90 (T/C) in E. faecium LHICA 28-4 and may explain the differences reported for those loci in other enterocin P-producing E. faecium strains. This work provides the first description of enterocin P-producing E. faecium strains in nonfermented foodstuffs and, in the case of E. faecium LHICA 51, the first report of an enterocin P-producing strain isolated from fish so far.

  10. Determination antimicrobial resistance profile of Acinetobacter strains isolated from hospitalized patients in Different Part of Taleghani Hospital (Ahvaz, Iran

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    Khadijah Ahmadi

    2014-10-01

    Full Text Available Background: The members of the genus Acinetobacter are Gram-negative cocobacilli that are frequently found in the environment but also in the hospital setting where they have been associated with outbreaks of nosocomial infections such as meningitis, endocarditis, skin and soft tissue infections, urinary tract infection, conjunctivitis, burn wound infection and bacteremia. This organism has been shown resistance to different antimicrobial agents. The aim of this study was to determination antibiotic resistance profile of Acinetobacter strains isolated from hospitalized patients in Taleghani hospital (Ahvaz, Iran. Materials and Methods: This cross-sectional study was conducted on 43 Acinetobacter strains isolated from hospitalized patients. Clinical specimens were cultured on microbiological media. Subsequently, drug susceptibility test was performed using the disc diffusion method according to CLSI recommendations. Results: Acinetobacter strains were isolated from different specimens consisting biopsy 24 (55.8%, wound 13 (30/2% and blood 6 (14%. In antimicrobial susceptibility testing, colistin exhibited the greatest activity (60.5% against isolated strains. 33 (76/7% isolates demonstrated resistance to imipenem. Conclusion: In outbreak situations, surveillance cultures of patients involved in the outbreak or who are deemed at risk for colonization/infection with the outbreak organism are often parts of the planned intervention.

  11. Insights on the virulence mechanisms of European Edwardsiella tarda strains isolated from turbot

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    Nuria Castro Iglesias

    2014-06-01

    Full Text Available Edwardsiella tarda is a common inhabitant of diverse ecological niches as well as a common guest of a high variety of animals including fish, reptiles, amphibians, chickens and other warm-blooded animals as humans. With regard to the aquatic environments, E. tarda has been described as the causative agent of infections in more than 20 fish species including some important fish species in aquaculture industry. Several potential pathogenic properties have been suggested to contribute to the infection process of E. tarda, which include adhesins, Type III and Type VI secretion system, and ability to survive and replicate in phagocytes, among others. Identification of these virulence-related genes is essential for understanding the pathogenesis of the species. Since E. tarda causes great losses in the Chinese aquaculture, great efforts have been recently devoted to study the pathogenicity mechanism of E. tarda in Asian countries. However, all these studies were conducted employing Asian isolates. Being E. tarda a pathogen of great economical concern in European turbot aquaculture and since the high intraspecific variability of E. tarda is well known, it becomes evident that additional pathogenicity studies conducted with non-Asiatic strains are needed. Enzymes such as chondroitinase are believed to play an important role in the pathogenicity of bacteria that cause infections (Tam et al., 1982. Chondroitinase activity was proposed to be one virulence contributor in Edwardsiella spp. and mediates the cartilage degradation in the chronic “hole-in-the-head” lesion. In Gram-negative bacteria, the most intensively studied quorum sensing systems rely on the use of N-acylhomoserine lactones (AHLs, which production is common among marine and fish pathogenic Proteobacteria, controlling the expression of key virulence factors. In the case of E. tarda, strain NUF251 from diseased flounder had the ability to produce two kinds of AHL molecules. It is likely

  12. Isolation and Fatty Acid Profile of Selected Microalgae Strains from the Red Sea for Biofuel Production

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    Khalid M. Abu-Salah

    2013-05-01

    Full Text Available The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS we screened for and isolated several microalgal strains from samples collected from the Red Sea. Relying on the fluorescence of BODIPY 505/515 (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diazasindacene and growth performance, four promising candidates were identified and the total lipid content and fatty acid profile was assessed for biofuels production. Selected isolates were classified as chlorophytes, belonging to three different genera: Picochlorum, Nannochloris and Desmochloris. The lipid contents were assessed microscopically by means of BODIPY 505/515-associated fluorescence to detect intracellular lipid bodies, which revealed several lipid drops in all selected strains. This result was confirmed by lipid gravimetric determination, which demonstrated that all strains under study presented inner cell lipid contents ranging from 20% to 25% of the biomass dry weight. Furthermore, the fatty acid methyl esters profile of all strains seems ideal for biodiesel production due to a low degree of polyunsaturated fatty acid methyl esters and high amount of palmitic and oleic acids.

  13. Detection, Characterization, and In Vitro and In Vivo Expression of Genes Encoding S-Proteins in Lactobacillus gallinarum Strains Isolated from Chicken Crops

    Science.gov (United States)

    Hagen, Karen E.; Guan, Le Luo; Tannock, Gerald W.; Korver, Doug R.; Allison, Gwen E.

    2005-01-01

    Thirty-eight isolates of Lactobacillus gallinarum cultured from the crops of broiler chickens were screened for the presence of genes encoding S-layer proteins. All of the isolates had two S-protein genes, which were designated Lactobacillus gallinarum S-protein (lgs) genes. One gene in each isolate was either lgsA or lgsB. The Lactobacillus isolates were further characterized by pulsed-field gel electrophoresis of DNA digests, which grouped the isolates into 17 genotypes (strains). The second gene in each of eight representative strains was sequenced and shown to differ among strains (lgsC, lgsD, lgsE, lgsF, lgsG, lgsH, and lgsI). The genome of each strain thus encoded a common S-protein (encoded by either lgsA or lgsB) and a strain-specific S-protein. The extraction of cell surface proteins from cultures of the eight strains showed that each strain produced a single S-protein that was always encoded by the strain-specific lgs gene. Two of the strains were used to inoculate chickens maintained in a protected environment which were Lactobacillus-free prior to inoculation. DNAs and RNAs extracted from the digesta of the chickens were used for PCR and reverse transcription-PCR, respectively, to demonstrate the presence and transcription of lgs genes in vivo. In both cases, only the strain-specific gene was transcribed. Both of the strains adhered to the crop epithelium, consistent with published data predicting that S-proteins of lactobacilli are adhesins. The results of this study provide a basis for the investigation of gene duplication and sequence variation as mechanisms by which bacterial strains of the same species can share the same habitat. PMID:16269691

  14. Characterization of rumen bacterial strains isolated from enrichments of rumen content in the presence of propolis.

    Science.gov (United States)

    de Aguiar, Sílvia Cristina; Zeoula, Lucia Maria; do Prado, Odimari Pricila Pires; Arcuri, Pedro Braga; Forano, Evelyne

    2014-11-01

    Propolis presents many biological properties, including antibacterial activities, and has been proposed as an additive in ruminant nutrition. Twenty bacterial strains, previously isolated from enrichments of Brazilian cow rumen contents in the presence of different propolis extracts (LLOS), were characterized using phenotyping and 16S rRNA identification. Seven strains were assigned to Streptococcus sp., most likely S. bovis, and were all degrading starch. One amylolytic lactate-utilizing strain of Selenomonas ruminantium was also found. Two strains of Clostridium bifermentans were identified and showed proteolytic activity. Two strains were assigned to Mitsuokella jalaludinii and were saccharolytic. One strain belonged to a Bacillus species and seven strains were affiliated with Escherichia coli. All of the 20 strains were able to use many sugars, but none of them were able to degrade the polysaccharides carboxymethylcellulose and xylans. The effect of three propolis extracts (LLOS B1, C1 and C3) was tested on the in vitro growth of four representative isolates of S. bovis, E. coli, M. jalaludinii and C. bifermentans. The growth of S. bovis, E. coli and M. jalaludinii was not affected by the three propolis extracts at 1 mg ml(-1). C. bifermentans growth was completely inhibited at this LLOS concentration, but this bacterium was partially resistant at lower concentrations. LLOS C3, with the lower concentration of phenolic compounds, was a little less inhibitory than B1 and C1 on this strain.

  15. Complete genome sequence of a novel Plum pox virus strain W isolate determined by 454 pyrosequencing.

    Science.gov (United States)

    Sheveleva, Anna; Kudryavtseva, Anna; Speranskaya, Anna; Belenikin, Maxim; Melnikova, Natalia; Chirkov, Sergei

    2013-10-01

    The near-complete (99.7 %) genome sequence of a novel Russian Plum pox virus (PPV) isolate Pk, belonging to the strain Winona (W), has been determined by 454 pyrosequencing with the exception of the thirty-one 5'-terminal nucleotides. This region was amplified using 5'RACE kit and sequenced by the Sanger method. Genomic RNA released from immunocaptured PPV particles was employed for generation of cDNA library using TransPlex Whole transcriptome amplification kit (WTA2, Sigma-Aldrich). The entire Pk genome has identity level of 92.8-94.5 % when compared to the complete nucleotide sequences of other PPV-W isolates (W3174, LV-141pl, LV-145bt, and UKR 44189), confirming a high degree of variability within the PPV-W strain. The isolates Pk and LV-141pl are most closely related. The Pk has been found in a wild plum (Prunus domestica) in a new region of Russia indicating widespread dissemination of the PPV-W strain in the European part of the former USSR.

  16. Complete genome sequence of Bifidobacterium breve CECT 7263, a strain isolated from human milk

    OpenAIRE

    Jiménez, Esther; Villar-Tajadura, M. Antonia; Marín, María; Fontecha, F. Javier; Requena, Teresa; Arroyo, Rebeca; Fernández, Leónides; Rodríguez, Juan M.

    2012-01-01

    Bifidobacterium breve is an actinobacterium frequently isolated from colonic microbiota of breastfeeding babies. Here, we report the complete and annotated genome sequence of a B. breve strain isolated from human milk, B. breve CECT 7263. The genome sequence will provide new insights into the biology of this potential probiotic organism and will allow the characterization of genes related to beneficial properties. © 2012, American Society for Microbiology.

  17. Determining the probiotic potential of cholesterol-reducing Lactobacillus and Weissella strains isolated from gherkins (fermented cucumber) and south Indian fermented koozh.

    Science.gov (United States)

    Anandharaj, Marimuthu; Sivasankari, Balayogan; Santhanakaruppu, Rajendran; Manimaran, Muthusamy; Rani, Rizwana Parveen; Sivakumar, Subramaniyan

    2015-06-01

    This study sought to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from traditionally fermented south Indian koozh and gherkin (cucumber). A total of 51 LAB strains were isolated, among which four were identified as Lactobacillus spp. and three as Weissella spp. The strains were screened for their probiotic potential. All isolated Lactobacillus and Weissella strains were capable of surviving under low pH and bile salt conditions. GI9 and FKI21 were able to survive at pH 2.0 and 0.50% bile salt for 3 h without losing their viability. All LAB strains exhibited inhibitory activity against tested pathogens and were able to deconjugate bile salt. Higher deconjugation was observed in the presence of sodium glycocholate (P Strain FKI21 showed maximum auto-aggregation (79%) and co-aggregation with Escherichia coli MTCC 1089 (68%). Exopolysaccharide production of LAB strains ranged from 68.39 to 127.12 mg/L (P Lactobacillus crispatus and Weissella koreensis, respectively. This is the first study to report isolation of W. koreensis FKI21 from fermented koozh and demonstrates its cholesterol-reducing potential. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  18. Genome sequences of two Leuconostoc pseudomesenteroides strains isolated from Danish dairy starter cultures

    DEFF Research Database (Denmark)

    Pedersen, Thomas Bæk; Kot, Witold Piotr; Hansen, L.H.

    2014-01-01

    The lactic acid bacterium Leuconostoc pseudomesenteroides can be found in mesophilic cheese starters, where it produces aromatic compounds from, e.g., citrate. Here, we present the draft genome sequences of two L. pseudomesenteroides strains isolated from traditional Danish cheese starters....

  19. Isolation, Fermentation Optimization and Performance Studies of a Novel Biosurfactant Producing Strain Bacillus amyloliquefaciens

    OpenAIRE

    Zhang, W.; Zhang, X.; Cui, H.

    2015-01-01

    In this research, biosurfactant-producing bacteria were isolated from the outlet sludge of a canteen and one promising strain was identified through 16S rDNA sequence as Bacillus amyloliquefaciens. This strain can utilize water-soluble carbon source and the FT-IR analysis indicated the biosurfactant was probably glycolipids. Further factors (fermentation time, temperature, carbon source, nitrogen source, ion concentration) affecting the biosurfactant production were determined. The optimum fe...

  20. Phylogenetic and Pathotypic Characterization of a Newcastle Disease Virus Strain Isolated from Ducks and Pigeons in Hubei, China

    Directory of Open Access Journals (Sweden)

    Y Wang

    Full Text Available ABSTRACT Newcastle disease is a highly contagious disease responsible for major outbreaks and considerable economic losses in the poultry industry in China. There is still little information available regarding gene characterization of the NDV, especially in ducks and pigeons. Therefore, the aim of this study was to investigate NDV isolated from ducks and pigeons in Hubei, China. In this study, three NDVs from ducks and pigeons were isolated between 2013 and 2015.The fusion protein (F gene of the NDV isolates was sequenced and phylogenetically analyzed. The clinical signs and gross histopathological lesions were examined. Phylogenetic analysis of these strains indicated that all the sequences are classified as genotype II. The isolates shared a 112 G-R-Q-G-R-L 117motif at the F protein cleavage site, indicating that these three isolates strains are lentogenic. Necropsy and histopathology showed the typical pathological changes. It was concluded that commercial ducks and pigeons in Hubei province carry lentogenic NDV strains with regular genetic divergence, indicating that these species may act as the main reservoirs of NDV in poultry. Therefore, strategies and surveillance should be undertaken to reduce the risk of ND outbreaks.

  1. Isolation and characterization of Halomonas sp. strain C2SS100, a hydrocarbon-degrading bacterium under hypersaline conditions.

    Science.gov (United States)

    Mnif, S; Chamkha, M; Sayadi, S

    2009-09-01

    To isolate and characterize an efficient hydrocarbon-degrading bacterium under hypersaline conditions, from a Tunisian off-shore oil field. Production water collected from 'Sercina' petroleum reservoir, located near the Kerkennah island, Tunisia, was used for the screening of halotolerant or halophilic bacteria able to degrade crude oil. Bacterial strain C2SS100 was isolated after enrichment on crude oil, in the presence of 100 g l(-1) NaCl and at 37 degrees C. This strain was aerobic, Gram-negative, rod-shaped, motile, oxidase + and catalase +. Phenotypic characters and phylogenetic analysis based on the 16S rRNA gene of the isolate C2SS100 showed that it was related to members of the Halomonas genus. The degradation of several compounds present in crude oil was confirmed by GC-MS analysis. The use of refined petroleum products such as diesel fuel and lubricating oil as sole carbon source, under the same conditions of temperature and salinity, showed that significant amounts of these heterogenic compounds could be degraded. Strain C2SS100 was able to degrade hexadecane (C16). During growth on hexadecane, cells surface hydrophobicity and emulsifying activity increased indicating the production of biosurfactant by strain C2SS100. A halotolerant bacterial strain Halomonas sp. C2SS100 was isolated from production water of an oil field, after enrichment on crude oil. This strain is able to degrade hydrocarbons efficiently. The mode of hydrocarbon uptake is realized by the production of a biosurfactant which enhances the solubility of hydrocarbons and renders them more accessible for biodegradation. The biodegradation potential of the Halomonas sp. strain C2SS100 gives it an advantage for possibly application on bioremediation of water, hydrocarbon-contaminated sites under high-salinity level.

  2. Enhanced production of xylanase from locally isolated fungal strain using agro-industrial residues under solid-state fermentation.

    Science.gov (United States)

    Abdullah, Roheena; Nisar, Kinza; Aslam, Aafia; Iqtedar, Mehwish; Naz, Shagufta

    2015-01-01

    This study is related to the isolation of fungal strain for xylanase production using agro-industrial residues. Forty fungal strains with xylanolytic potential were isolated by using xylan agar plates and quantitatively screened in solid-state fermentation. Of all the tested isolates, the strain showing highest ability to produce xylanase was assigned the code Aspergillus niger LCBT-14. For the enhanced production of the enzyme, five different fermentation media were evaluated. Out of all media, M4 containing wheat bran gave maximum enzyme production. Effect of different variables including incubation time, temperature, pH, carbon and nitrogen sources has been investigated. The optimum enzyme production was obtained after 72 h at 30°C and pH 4. Glucose as a carbon source while ammonium sulphate and yeast extract as nitrogen sources gave maximum xylanase production (946 U/mL/min). This study was successful in producing xylanase by A. niger LCBT-14 economically by utilising cheap indigenous substrate.

  3. Phenotypic, molecular characterization, antimicrobial susceptibility and draft genome sequence of Corynebacterium argentoratense strains isolated from clinical samples

    Directory of Open Access Journals (Sweden)

    I. Fernández-Natal

    2016-03-01

    Full Text Available During a 12-year period we isolated five Corynebacterium argentoratense strains identified by phenotypic methods, including the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF and 16S rRNA gene sequencing. In addition, antimicrobial susceptibility was determined, and genome sequencing for the detection of antibiotic resistance genes was performed. The organisms were isolated from blood and throat cultures and could be identified by all methods used. All strains were resistant to cotrimoxazole, and resistance to β-lactams was partly present. Two strains were resistant to erythromycin and clindamycin. The draft genome sequences of theses isolates revealed the presence of the erm(X resistance gene that is embedded in the genetic structure of the transposable element Tn5423. Although rarely reported as a human pathogen, C. argentoratense can be involved in bacteraemia and probably in other infections. Our results also show that horizontal transfer of genes responsible for antibiotic resistance is occurring in this species.

  4. Culture supernatants from V. cholerae O1 El Tor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity.

    Science.gov (United States)

    Vidal, Jorge E; Enríquez-Rincón, Fernando; Giono-Cerezo, Silvia; Ribas-Aparicio, Rosa María; Figueroa-Arredondo, Paula

    2009-01-01

    To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+) and a non-toxigenic Mexican strain (CM 91-3, ctxAB-). Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.

  5. Molecular epidemiology of Staphylococcus aureus strains isolated from inpatients with infected diabetic foot ulcers in an Algerian University Hospital.

    Science.gov (United States)

    Djahmi, N; Messad, N; Nedjai, S; Moussaoui, A; Mazouz, D; Richard, J-L; Sotto, A; Lavigne, J-P

    2013-09-01

    Staphylococcus aureus is the most common pathogen cultured from diabetic foot infection (DFI). The consequence of its spread to soft tissue and bony structures is a major causal factor for lower-limb amputation. The objective of the study was to explore ecological data and epidemiological characteristics of S. aureus strains isolated from DFI in an Algerian hospital setting. Patients were included if they were admitted for DFI in the Department of Diabetology at the Annaba University Hospital from April 2011 to March 2012. Ulcers were classified according to the Infectious Diseases Society of America/International Working Group on the Diabetic Foot classification system. All S. aureus isolates were analysed. Using oligonucleotide arrays, S. aureus resistance and virulence genes were determined and each isolate was affiliated to a clonal complex. Among the 128 patients, 277 strains were isolated from 183 samples (1.51 isolate per sample). Aerobic Gram-negative bacilli were the most common isolated organisms (54.9% of all isolates). The study of ecological data highlighted the extremely high rate of multidrug-resistant organisms (MDROs) (58.5% of all isolates). The situation was especially striking for S. aureus [(85.9% were methicillin-resistant S. aureus (MRSA)], Klebsiella pneumonia (83.8%) and Escherichia coli (60%). Among the S. aureus isolates, 82.2% of MRSA belonged to ST239, one of the most worldwide disseminated clones. Ten strains (13.7%) belonged to the European clone PVL+ ST80. ermA, aacA-aphD, aphA, tetM, fosB, sek, seq, lukDE, fnbB, cap8 and agr group 1 genes were significantly associated with MRSA strains (p study shows for the first time the alarming prevalence of MDROs in DFI in Algeria. ©2013 The Authors Clinical Microbiology and Infection ©2013 European Society of Clinical Microbiology and Infectious Diseases.

  6. Isolation and identification of Mycoplasma mycoides cluster strains from goats in Chongqing, China

    Directory of Open Access Journals (Sweden)

    Wang Haoju

    2014-03-01

    Full Text Available In order to evaluate the prevalence of the Mycoplasma mycoides cluster in goats in Chongqing, China, an epidemiological survey in this area was carried out. A total of 68 samples were subjected to bacteria isolation on Hartley’s medium. Four isolates (three from lung tissue and one from nasal discharges were recovered from the samples and identified as the Mycoplasma species by their morphological and biochemical characteristics. They were further confirmed by PCR using 16S rRNA specific primer pairs and by restriction enzyme analysis. In vitro antimicrobial susceptibility of the isolates indicated that some strains had developed resistance to the antibiotics tested. This is the first report on the isolation, identification, and molecular characterisation of Mycoplasma species isolated from goats in Chongqing. This study also revealed a prevalence of Mycoplasma species infection in goats in this area.

  7. [Identification of mycobacteria by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry--using reference strains and clinical isolates of Mycobacterium].

    Science.gov (United States)

    Niitsuma, Katsunao; Saito, Miwako; Koshiba, Shizuko; Kaneko, Michiyo

    2014-05-01

    Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) method is being played an important role for the inspection of clinical microorganism as a rapid and the price reduction. Mass spectra obtained by measuring become points of identification whether the peak pattern match any species mass spectral pattern. We currently use MALDI-TOF MS for rapid and accurate diagnosis of inactivated reference and clinical isolates of Mycobacterium because of the improved pretreatment techniques compared with former inspection methods that pose a higher risk of infection to the operator. The identification matching rate of score value (SV) peak pattern spectra was compared with that of conventional methods such as strain diffusion/amplification. Also, cultures were examined after a fixed number of days. Compared with the initial inspection technique, the pretreatment stage of current MALDI-TOF MS inspection techniques can improve the analysis of inactivated acid-fast bacteria that are often used as inspection criteria strains of clinical isolates. Next, we compared the concordance rate for identification between MALDI-TOF MS and conventional methods such as diffusion/amplification by comparison of peak pattern spectra and evaluated SV spectra to identify differences in the culture media after the retention period. In examination of 158 strains of clinical isolated Mycobacterium tuberculosis complex (MTC), the identification coincidence rate in the genus level in a matching pattern was 99.4%, when the species level was included 94.9%. About 37 strains of nontuberculous mycobacteria (NTM), the identification coincidence rate in the genus level was 94.6%. M. bovis BCG (Tokyo strain) in the reference strain was judged by the matching pattern to be MTC, and it suggested that they are M. tuberculosis and affinity species with high DNA homology. Nontuberculous mycobacterial M. gordonae strain JATA 33-01 shared peak pattern spectra, excluding the

  8. Genome Sequence of Aeribacillus pallidus Strain GS3372, an Endospore-Forming Bacterium Isolated in a Deep Geothermal Reservoir

    OpenAIRE

    Sevasti Filippidou; Marion Jaussi; Thomas Junier; Tina Wunderlin; Nicole Jeanneret; Simona Regenspurg; Po-E Li; Chien-Chi Lo; Shannon Johnson; Kim McMurry; Cheryl D. Gleasner; Momchilo Vuyisich; Patrick S. Chain; Pilar Junier

    2015-01-01

    The genome of strain GS3372 is the first publicly available strain of Aeribacillus pallidus. This endospore-forming thermophilic strain was isolated from a deep geothermal reservoir. The availability of this genome can contribute to the clarification of the taxonomy of the closely related Anoxybacillus, Geobacillus, and Aeribacillus genera.

  9. Characterization of Thermotolerant Chitinases Encoded by a Brevibacillus laterosporus Strain Isolated from a Suburban Wetland

    Directory of Open Access Journals (Sweden)

    Pulin Liu

    2015-12-01

    Full Text Available To isolate and characterize chitinases that can be applied with practical advantages, 57 isolates of chitin-degrading bacteria were isolated from the soil of a suburban wetland. 16S rRNA gene analysis revealed that the majority of these strains belonged to two genera, Paenibacillus and Brevibacillus. Taking thermostability into account, the chitinases (ChiA and ChiC of a B. laterosporus strain were studied further. Ni-NTA affinity-purified ChiA and ChiC were optimally active at pH 7.0 and 6.0, respectively, and showed high temperature stability up to 55 °C. Kinetic analysis revealed that ChiC has a lower affinity and stronger catalytic activity toward colloidal chitin than ChiA. With their stability in a broad temperature range, ChiA and ChiC can be utilized for the industrial bioconversion of chitin wastes into biologically active products.

  10. Phage type and sensitivity to antibiotics of Staphylococcus aureus film-forming strains isolated from airway mucosa

    Directory of Open Access Journals (Sweden)

    O. S. Voronkova

    2014-10-01

    Full Text Available Today film-forming strains of bacteria play very important role in clinical pathology. Staphylococci are ones of most dangerous of them. This bacteria can determine different pathological processes, for example, complication of airway mucosa. The ability to form a biofilm is one of the main properties of nosocomial strains. These strains should be monitored and their carriers are to be properly treated. To determine the origin of staphylococci strains we used bacteriophages from the International kit. The aim of research was to determine the phage type of staphylococci film-forming strains, that were isolated from naso-pharingial mucosa. Phage typing has been carried out for 16 film-forming strains of S. aureus. To solve this problem, we used the International phage kit by Fisher’s method. As a result, sensitivity to phages from the International kit showed 53.8% of studied strains of S. aureus. 64.3% of sensitivity strains were lysed by one of the phage, 21.4% – were by two of the phages, 14.3% – by three of the phages. Isolates were sensitive to phages: 81 – 42.9%, 75 – 35.7%, 28.6% were sensitive to phages 47 and 53. All cases of detection of sensitivity to phage 47 coincided with the ability to form biofilm. Among non-film-forming strains there was no sensitive strains for this phage. Film-forming strains resist to erythromycin (62.5%, ciprofloxacin (43.8%, gentamicin (56.3%, tetracycline (87.5%, amoxicillin (93.8%, and cefuroxime (37.5%. All cases of sensitivity to phage 47 coincided with resistance to erythromycin, amoxicillin and tetracycline. For two of these strains, we also defined resistance to gentamicin and for one of them – to ciprofloxacin. Results of research allowed to relate the bacterial cultures for determining the type. This may have implications for studying of film-forming ability, because surface structures of bacterial cell take place in this process. Belonging of an isolate to specific phage type may

  11. The effect of rhamnolipid biosurfactant produced by Pseudomonas fluorescens on model bacterial strains and isolates from industrial wastewater.

    Science.gov (United States)

    Vasileva-Tonkova, Evgenia; Sotirova, Anna; Galabova, Danka

    2011-02-01

    In this study, the effect of rhamnolipid biosurfactant produced by Pseudomonas fluorescens on bacterial strains, laboratory strains, and isolates from industrial wastewater was investigated. It was shown that biosurfactant, depending on the concentration, has a neutral or detrimental effect on the growth and protein release of model Gram (+) strain Bacillus subtilis 168. The growth and protein release of model Gram (-) strain Pseudomonas aeruginosa 1390 was not influenced by the presence of biosurfactant in the medium. Rhamnolipid biosurfactant at the used concentrations supported the growth of some slow growing on hexadecane bacterial isolates, members of the microbial community. Changes in cell surface hydrophobicity and permeability of some Gram (+) and Gram (-) isolates in the presence of rhamnolipid biosurfactant were followed in experiments in vitro. It was found that bacterial cells treated with biosurfactant became more or less hydrophobic than untreated cells depending on individual characteristics and abilities of the strains. For all treated strains, an increase in the amount of released protein was observed with increasing the amount of biosurfactant, probably due to increased cell permeability as a result of changes in the organization of cell surface structures. The results obtained could contribute to clarify the relationships between members of the microbial community as well as suggest the efficiency of surface properties of rhamnolipid biosurfactant from Pseudomonas fluorescens making it potentially applicable in bioremediation of hydrocarbon-polluted environments.

  12. Isolation of cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and molecular comparison with dairy-related Lactobacillus helveticus strains

    DEFF Research Database (Denmark)

    Jensen, Marie Elisabeth Penderup; Ardö, Ylva Margareta; Vogensen, Finn Kvist

    2009-01-01

    -related Lact. helveticus strains indicated that one isolate was a Lact. helveticus. Partial sequencing of 16S rRNA confirmed this, and the remaining four strains were identified as Lactobacillus delbrueckii, Lactobacillus fermentum and Enterococcus faecium. The rep-PCR profile of the isolated Lact. helveticus......Aims: To isolate cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and compare them with dairy-related Lactobacillus helveticus strains using molecular typing methods. Methods and Results: The number of thermophilic bacteria in seven commercial cheeses...

  13. A Pseudomonas aeruginosa strain isolated from a contact lens-induced acute red eye (CLARE) is protease-deficient.

    Science.gov (United States)

    Estrellas, P S; Alionte, L G; Hobden, J A

    2000-03-01

    Pseudomonas aeruginosa proteases are thought to be important virulence factors in the pathogenesis of corneal disease. This study examined protease production from two strains of P. aeruginosa responsible for two very distinct clinical diseases: strain Paer1, isolated from a Contact Lens-induced Acute Red Eye (CLARE), and strain KEI 1025, isolated from a corneal ulcer. Strains were compared to a laboratory strain (ATCC 19660) known to produce severe keratitis in experimentally infected mice for protease production and for ocular virulence. Protease production was examined with colorimetric assays, gelatin zymography and western blots. Elastase A activity was quantitated with a staphylolytic assay. Ocular virulence was examined using a mouse scratch model of keratitis. In contrast to strains KEI 1025 or ATCC 19660, Paer1 was unable to produce enzymatically active elastase A, elastase, and protease IV. All three strains produced active alkaline protease. Strains KEI 1025 and ATCC 19660 produced a fulminant keratitis in mice whereas Paer1 produced a mild transient infection. Restoration of elastase activity in Paer1 via genetic complementation did not result in a virulent phenotype. Co-infection of mouse eyes with strains Paer1 and ATCC 19660 resulted in the eventual loss of Paer1 from corneal tissue. These studies suggest that P. aeruginosa elastase A and/or protease IV, but not alkaline protease or elastase, contribute to the ocular virulence of this organism.

  14. Isolation and Characterization of Agrobacterium Strains from Soil: A Laboratory Capstone Experience

    Directory of Open Access Journals (Sweden)

    Kim R. Finer

    2016-12-01

    Full Text Available In this investigation, the students’ goal was to isolate and characterize Agrobacterium strains from soil. Following selection and enrichment on 1A-t medium, putative Agrobacterium isolates were characterized by Gram stain reaction and biochemical tests. Isolates were further evaluated using polymerase chain reaction (PCR with different primer sets designed to amplify specific regions of bacterial deoxyribonucleic acid (DNA. Primer sets included AGRH to identify isolates that were members of the Rhizobiaceae, BIOVAR1 primers to identify members of Agrobacterium biovar group I, and a third set, VIRG, to determine presence of virG (only present in pathogenic Agrobacterium strains. During the investigation, students applied previously learned techniques including serial dilution, use of selective/differential media, staining protocols, biochemical analysis, molecular analysis via PCR, and electrophoresis. Students also gained practical experience using photo documentation to record data for an eventual mock journal publication of the capstone laboratory experience. Pre- and post-evaluation of class content knowledge related to the techniques, protocols, and learning objectives of these laboratories revealed significant learning gains in the content areas of Agrobacterium–plant interactions (p ≤ 0.001 and molecular biology (p ≤ 0.01. The capstone journal assignment served as the assessment tool to evaluate mastery and application of laboratory technique, the ability to accurately collect and evaluate data, and critical thinking skills associated with experimental troubleshooting and extrapolation. Analysis of journal reports following the capstone experience showed significant improvement in assignment scores (p ≤ 0.0001 and attainment of capstone experience learning outcomes.

  15. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    Directory of Open Access Journals (Sweden)

    Baba Ngom

    2014-01-01

    Full Text Available A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa and Dexing copper mine (China, Asia, was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains.

  16. An investigation of vancomycin minimum inhibitory concentration creep among methicillin-resistant Staphylococcus aureus strains isolated from pediatric patients and healthy children in Northern Taiwan.

    Science.gov (United States)

    Chang, Chia-Ning; Lo, Wen-Tsung; Chan, Ming-Chin; Yu, Ching-Mei; Wang, Chih-Chien

    2017-06-01

    The phenomenon of vancomycin minimum inhibitory concentration (MIC) creep is an increasingly serious problem in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. In this study, we investigated the vancomycin and daptomycin MIC values of MRSA strains isolated from pediatric patients and MRSA colonized healthy children. Then, we assessed whether there was evidence of clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. We collected clinical MRSA isolates from pediatric patients and from healthy children colonized with MRSA during 2008-2012 at a tertiary medical center in northern Taiwan and obtained vancomycin and daptomycin MIC values using the Etest method. Pulse-field gel electrophoresis (PFGE) and staphylococcal cassette chromosome (SCCmec) typing were used to assess clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. A total 195 MRSA strains were included in this study; 87 were isolated patients with a clinical MRSA infection, and the other 108 strains from nasally colonized healthy children. Vancomycin MIC≥1.5 μg/mL was seen in more clinical isolates (60/87, 69%) than colonized isolates (32/108, 29.6%), p < 0.001. The PFGE typing of both strains revealed multiple pulsotypes. Vancomycin MIC creeps existed in both clinical MRSA isolates and colonized MRSA strains. Great diversity of PFGE typing was in both strains collected. There was no association between the clinical and colonized MRSA isolates with vancomycin MIC creep. Copyright © 2016. Published by Elsevier B.V.

  17. Genome Sequences of Two Pseudomonas syringae pv. tomato Race 1 Strains, Isolated from Tomato Fields in California

    OpenAIRE

    Thapa, Shree P.; Coaker, Gitta

    2016-01-01

    Pseudomonas syringae pv. tomato race 1 strains have evolved to overcome genetic resistance in tomato. Here, we present the draft genome sequences of two race 1 P.?syringae pv. tomato strains, A9 and 407, isolated from diseased tomato plants in California.

  18. Genome Sequence of Canine Parvovirus Strain SC02/2011, Isolated from a Puppy with Severe Diarrhea in South China

    Science.gov (United States)

    Cheng, Yi; Ji, Yikuan; Wang, Yu; Sun, Leilei; Huang, Jiaxin

    2012-01-01

    A widespread hemorrhagic gastroenteritis in young dogs occurred in South China. A virulent field canine parvovirus (CPV) strain, SC02/2011, was isolated from a puppy showing enteric signs in Guangdong, China. The genome of CPV strain SC02/2011 was sequenced and analyzed, which will promote a better understanding of the molecular epidemiology and genetic diversity of CPV field isolates in South China. PMID:23166228

  19. Complete Genome Sequences of Porcine Epidemic Diarrhea Virus Strains JSLS-1/2015 and JS-2/2015 Isolated from China.

    Science.gov (United States)

    Tao, Jie; Li, Benqiang; Zhang, Chunling; Liu, Huili

    2016-11-10

    Two porcine epidemic diarrhea virus (PEDV) strains, JSLS-1/2015 and JS-2/2015, were isolated from piglets with watery diarrhea in South China. Two genomic sequences were highly homologous to the attenuated DR13 strain. Furthermore, JSLS-1/2015 contains a 24-amino-acid deletion in open reading frame 1b, which was first reported in PEDV isolates. Copyright © 2016 Tao et al.

  20. Clonal structure of Streptococcus sanguinis strains isolated from endocarditis cases and the oral cavity.

    Science.gov (United States)

    Do, T; Gilbert, S C; Klein, J; Warren, S; Wade, W G; Beighton, D

    2011-10-01

    A collection of Streptococcus sanguinis strains from patients with endocarditis (n = 21) and from the oral cavity (n = 34) was subjected to a multi-locus sequence typing analysis using seven housekeeping genes, carbamoyl-phosphate synthetase (carB), Co/Zn/Cd efflux system component (czcD), d-alanyl-d-alanine ligase (ddl), DNA polymerase III (dnaX), glucose-6-phosphate dehydrogenase (gdh), DNA-directed RNA polymerase, beta subunit (rpoB) and superoxide dismutase (sodA). The scheme was expanded by the inclusion of two the putative virulence genes, bacitracin-resistance protein (bacA) and saliva-binding protein (ssaB), to increase strain discrimination. Extensive intra-species recombination was apparent in all genes but inter-species recombination was also apparent with strains apparently harbouring gdh and ddl from unidentified sources and one isolate harboured a sodA allele apparently derived from Streptococcus oralis. The recombination/mutation ratio for the concatenated housekeeping gene sequences was 1.67 (95% confidence limits 1.25-2.72) and for the two virulence genes the r/m ratio was 3.99 (95% confidence limits 1.61-8.72); recombination was the major driver for genetic variation. All isolates were distinct and the endocarditis strains did not form distinct sub-clusters when the data were analysed using ClonalFrame. These data support the widely held opinion that infecting S. sanguinis strains are opportunistic human pathogens. © 2011 John Wiley & Sons A/S.

  1. Plasmid Mediated Antibiotic and Heavy Metal Resistance in Bacillus Strains Isolated From Soils in Rize, Turkey

    Directory of Open Access Journals (Sweden)

    Elif SEVİM

    2015-09-01

    Full Text Available Fifteen Bacillus strains which were isolated from soil samples were examined for resistance to 17 different antibiotics (ampicillin, methicillin, erythromycin, norfloxacin, cephalotine, gentamycin, ciprofloxacin, streptomycin, tobramycin, chloramphenicol, trimethoprim-sulfamethoxazole, tetracycline, vancomycin, oxacilin, neomycin, kanamycin and, novabiocin and to 10 different heavy metals (copper, lead, cobalt, chrome, iron, mercury, zinc, nickel, manganese and, cadmium and for the presence of plasmid DNA. A total of eleven strains (67% were resistant to at least one antibiotic. The most common resistance was observed against methicillin and oxacillin. The most resistance strains were found as Bacillus sp. B3 and Bacillus sp. B11. High heavy metal resistance against copper, chromium, zinc, iron and nickel was detected, but mercury and cobalt resistance was not detected, except for 3 strains (B3, B11, and B12 which showed mercury resistance. It has been determined that seven Bacillus strains have plasmids. The isolated plasmids were transformed into the Bacillus subtilis W168 and it was shown that heavy metal and antibiotic resistance determinants were carried on these plasmids. These results showed that there was a correlation between plasmid content and resistance for both antibiotic and heavy metal resistance

  2. Molecular Characterization of Yeast Strains Isolated from Different Sources by Restriction Fragment Length Polymorphism

    International Nuclear Information System (INIS)

    Ali, M. S.; Latif, Z.

    2016-01-01

    Various molecular techniques like analysis of the amplified rDNA internal transcribed spacers (ITS), intragenic spacers and total ITS region analysis by restriction fragment length polymorphism (RFLP) has been introduced for yeast identification but there are limited databases to identify yeast species on the basis of 5.8S rDNA. In this study, twenty nine yeast strains from various sources including spoiled fruits, vegetables, foodstuffs, and concentrated juices were characterized by PCR-RFLP. PCR-RFLP has been used to characterize yeasts present in different spoiled food samples after isolation of the yeasts. By using this technique, the isolated yeast strains were characterized by direct 5.8S-ITS rDNA region amplification. RFLP analysis was applied to each of the amplification products (varied from 400bp to 800bp) detected, and the corresponding yeast identifications were made according to each specific restriction patterns obtained after treatment with two endonucleases TaqI and HaeIII which yielded a specific banding pattern for each species. For further confirmation amplified products of eleven selected isolates were sequenced and blast on NCBI. Both RFLP and sequence analyses of the strains with accession nos. KF472163, KF472164, KF472165, KF472166, KF472167, KF472168, KF472169, KF472170, KF472171, KF472172, KF472173 gave significantly similar results. The isolates were found to belong five different yeast species including; Candida spp., Pichia spp., Kluyveromyces spp., Clavispora spp. and Hanseniaspora spp. This method provides a fast, easy, reliable and authentic way for determining yeast population present in different type of samples, as compared to traditional characterization technique. (author)

  3. Cadophora malorum Cs-8-1 as a new fungal strain producing gibberellins isolated from Calystegia soldanella.

    Science.gov (United States)

    You, Young-Hyun; Yoon, Hyeokjun; Kang, Sang-Mo; Woo, Ju-Ri; Choo, Yeon-Sik; Lee, In-Jung; Shin, Jae-Ho; Kim, Jong-Guk

    2013-07-01

    Fourteen endophytic fungi with different colony morphologies were isolated from the roots of Calystegia soldanella. Endophytic fungi isolated from C. soldanella were identified by internal transcribed spacer (ITS) region. To verify plant growth promotion (PGP), culture filtrates of isolated endophytic fungi were treated in Waito-c rice (WR) and C. soldanella seedlings. Culture filtrates of Cs-8-1 fungal strain had advanced PGP activity. The presence of physiologically bioactive gibberellins (GA) GA(1) (1.213 ng ml(-1)), GA(3) (1.292 ng ml(-1)), GA(4) (3.6 ng ml(-1)), GA(7) (1.328 ng ml(-1)), other inactive GA(9) (0.796 ng ml(-1)) and GA(12) (0.417 ng ml(-1)), GA(20) (0.302 ng ml(-1)), GA(24) (1.351 ng ml(-1)), GA(34) (0.076 ng ml(-1)), and GA(53) (0.051 ng ml(-1)) in culture filtrates of Cs-8-1 fungal strain was detected. The Cs-8-1 fungal strain was confirmed as a producer of GAs. Molecular analysis of sequences showed high similarity of 99% to Cadophora malorum. Consequentially, the Cs-8-1 fungal strain was identified as a new C. malorum producing GAs. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Draft Genome Sequence of a Novel Lactobacillus salivarius Strain Isolated from Piglet.

    Science.gov (United States)

    Mackenzie, Donald A; McLay, Kirsten; Roos, Stefan; Walter, Jens; Swarbreck, David; Drou, Nizar; Crossman, Lisa C; Juge, Nathalie

    2014-02-13

    Lactobacillus salivarius is part of the vertebrate indigenous microbiota of the gastrointestinal tract, oral cavity, and milk. The properties associated with some L. salivarius strains have led to their use as probiotics. Here we describe the draft genome of the pig isolate L. salivarius cp400, providing insights into host-niche specialization.

  5. The hydrolytic enzymes produced by fungi strains isolated from the sand and soil of recreational areas

    Science.gov (United States)

    Kurnatowski, Piotr; Wójcik, Anna; Błaszkowska, Joanna; Góralska, Katarzyna

    2016-10-01

    The pathogenicity of fungi depends on, inter alia, the secretion of hydrolytic enzymes. The aim of this study was to determine the enzymatic activity of yeasts and yeast-like fungi isolated from children’s recreation areas, and compare the results with literature data of strains obtained from patients with mycoses. The enzymatic activity of 96 strains was assessed using an API ZYM kit (bioMerieux, France) and their biotypes were established. The fungal species were found to produce from 16 to 19 hydrolases: the most active were: leucine arylamidase (e5), acid phosphatase (e10), alkaline phosphatase (e1), naphthol-AS-BI-phosphohydrolase (e11), esterase – C4 (e2), β-galac - tosidase (e13) and β-glucosidase (e16). In addition, 13 biotypes characteristic of particular species of fungi were defined. Most strains could be categorized as biotypes C2 – 39.5% and A – 26%. The examined fungal strains isolated from recreational areas have selected biochemical characteristics i.e. production of hydrolases, which demonstrate their pathogenicity. They produce a number of enzymes which are also present in strains isolated from patients with mycoses, including: leucine arylamidase (e5), acid phosphatase (e10), naphthol-AS-BI-phosphohydrolase (e11) and alkaline phosphatase (e1). The biotypes identified in the course of this study (A, B3, B4, C1, C6 and D3) have been also reported in cases of fungal infection. Therefore, the fungi present in the sand and soil of recreational have pathogenic properties and are possible factors of fungal infection among children.

  6. [Identification and Nitrogen Removal Characteristics of a Heterotrophic Nitrification-Aerobic Denitrification Strain Isolated from Marine Environment].

    Science.gov (United States)

    Sun, Qing-hua; Yu, De-shuang; Zhang, Pei-yu; Lin, Xue-zheng; Li, Jin

    2016-02-15

    A heterotrophic nitrification-aerobic denitrification strain named y5 was isolated from marine environment by traditional microbial isolation method using seawater as medium. It was identified as Klebsiella sp. based on the morphological, physiological and 16S rRNA sequence analysis. The experiment results showed that the optimal carbon resource was sodium citrate; the optimal pH was 7.0; and the optimal C/N was 17. The strain could use NH4Cl, NaNO2 and KNO3 as sole nitrogen source, and the removal efficiencies were77.07%, 64.14% and 100% after 36 hours, respectively. The removal efficiency reached 100% after 36 hours in the coexistence of NH4Cl, NaNO2 and KNO3. The results showed that the strain y5 had independent and efficient heterotrophic nitrification and aerobic denitrification activities in high salt wastewater.

  7. Sequence analysis and typing of Saprolegnia strains isolated from freshwater fish from Southern Chinese regions

    Directory of Open Access Journals (Sweden)

    Siya Liu

    2017-09-01

    Full Text Available Saprolegniasis, caused by Saprolegnia infection, is one of the most common diseases in freshwater fish. Our study aimed to determine the epidemiological characteristics of saprolegniasis in Chinese regions of high incidence. Saprolegnia were isolated and identified by morphological and molecular methods targeting the internal transcribed spacer (ITS ribosomal DNA (rDNA and building neighbor-joining (NJ and maximum parsimony (MP phylogenetic trees. The ITS sequences of eight isolated strains were compared with GenBank sequences and all strains fell into three clades: CLADE1 (02, LP, 04 and 14, CLADE2 (S1, and CLADE3 (CP, S2, L5 and the reference ATCC200013. Isolates 02 and LP shared 80% sequence similarity with S. diclina, S. longicaulis, S. ferax, S. mixta, and S. anomalies. Further, isolates 04 and 14 shared 80% similarity with S. bulbosa and S. oliviae. Finally, extremely high ITS sequence similarities were identified between isolates S1 and S. australis (100%; CP and S. hypogyna (96%; and S2, L5, ATCC200013 and S. salmonis (98%. This research provides insights into the identification, prevention and control of saprolegniasis pathogens and the potential development of effective drugs.

  8. Antibiotic susceptibility of Legionella strains isolated from public water sources in Macau and Guangzhou.

    Science.gov (United States)

    Xiong, Lina; Yan, He; Shi, Lei; Mo, Ziyao

    2016-12-01

    The purpose of this study was to investigate the susceptibility of waterborne strains of Legionella to eight antimicrobials commonly used in legionellosis therapy. The minimum inhibitory concentrations (MICs) of 66 environmental Legionella strains, isolated from fountains and cooling towers of public facilities (hotels, schools, and shopping malls) in Macau and Guangzhou, were tested using the microdilution method in buffered yeast extract broth. The MIC 50 /MIC 90 values for erythromycin, cefotaxime (CTX), doxycycline (DOC), minocycline (MIN), azithromycin, ciprofloxacin, levofloxacin (LEV), and moxifloxacin were 0.125/0.5 mg/L, 4/8 mg/L, 8/16 mg/L, 4/8 mg/L, 0.125/0.5 mg/L, 0.031/0.031 mg/L, 0.031/0.031 mg/L, and 0.031/0.062 mg/L, respectively. Legionella isolates were inhibited by either low concentrations of macrolides and fluoroquinolones, or high concentrations of CTX and tetracycline drugs. LEV was the most effective drug against different Legionella species and serogroups of L. pneumophila isolates. The latter were inhibited in decreasing order by MIN > CTX >DOC, while non-L. pneumophila isolates were inhibited by CTX> MIN >DOC. In this study, we evaluated drug resistance of pathogenic bacteria from the environment. This may help predict the emergence of drug resistance, improve patient outcomes, and reduce hospitalization costs.

  9. Changes of Raffinose and Stachyose in Soy Milk Fermentation by Lactic Acid Bacteria From Local Fermented Foods of Indonesian

    Directory of Open Access Journals (Sweden)

    Sumarna

    2008-01-01

    Full Text Available The objective of this study was to evaluate the fermentative characteristics of lactic acid bacteria isolated from local fermented foods and consume raffinose and stachyose during fermentation soymilk. Lactobacillus plantarum pentosus SMN, 01, Lactobacillus casei subsp rhamnosus FNCC, 098, Lactobacillus casei subsp rhamnosus FNCC, 099, Streptococcus thermofilus, 001, Lactobacillus delbrueckii subsp. bulgaricus FNCC, 0045, Lactobacillus plantarum SMN, 25, and Lactobacillus plantarum pentosus FNCC, 235 exhibited variable α-galactosidase activity with Lactobacillus plantarum SMN, 25, showing the highest activity in MRS supplemented media. However, all organisms reached the desired therapeutic level (10^8 cfu/mL likely due to their ability to metabolize oligosaccharides during fermentation in soymilk at 41 °C. The oligosaccharide metabolism depended on α-galactosidase activity. Lactobacillus plantarum SMN, 25, L. plantarum pentosus SMN, 01 and Lactobacillus plantarum pentosus FNCC, 235 reduced raffinose and stachyose by 81.5, 73.0, 67.0 %, and 78.0, 72.5, 66.0 % respectively in soymilk.

  10. Nitrosomonas communis strain YNSRA, an ammonia-oxidizing bacterium, isolated from the reed rhizoplane in an aquaponics plant.

    Science.gov (United States)

    Tokuyama, Tatsuaki; Mine, Atsusi; Kamiyama, Kaoru; Yabe, Ryuichi; Satoh, Kazuo; Matsumoto, Hirotoshi; Takahashi, Reiji; Itonaga, Koji

    2004-01-01

    An ammonia-oxidizing bacterium (strain YNSRA) was isolated from the rhizoplane of the reed (Phragmites communis) used in an aquaponics plant which is a wastewater treatment plant. Strain YNSRA was identified as Nitrosomonas communis by taxonomic studies. The hydroxylamine-cytochrome c reductase (HCR) of strain YNSRA was found to have a higher activity (25.60 u/mg) than that of Nitrosomonas europaea ATCC25978T (8.94 u/mg). Ribulose-1,5-bisphosphate carboxylase (RubisCO) activity was detected at very low levels in strain YNSRA, whereas strain ATCC25978T had definite activity.

  11. Complete genome sequence of Yersinia pestis strain 91001, an isolate avirulent to humans

    DEFF Research Database (Denmark)

    Song, Yajun; Tong, Zongzhong; Wang, Jin

    2004-01-01

    pseudo-genes. Due to the rearrangements mediated by insertion elements, the structure of the 91001 chromosome shows dramatic differences compared with CO92 and KIM. Based on the analysis of plasmids and chromosome architectures, pseudogene distribution, nitrate reduction negative mechanism and gene...... comparison, we conclude that strain 91001 and other strains isolated from M. brandti might have evolved from ancestral Y. pestis in a different lineage. The large genome fragment deletions in the 91001 chromosome and some pseudogenes may contribute to its unique nonpathogenicity to humans and host...

  12. Isolation and molecular identification of a UV-resistant strain of Dietzia maris and antioxidant activity of pigment

    Directory of Open Access Journals (Sweden)

    Narges Zamanian

    2016-09-01

    Full Text Available Introduction: The ability of radioresistant bacteria to survive high levels of UV radiation has been linked to their strong DNA repair systems and ability to produce primary and secondary metabolic products. The biosynthesis of pigments provides an opportunity for bacteria to live in radiation-rich environment. Recent radiation-responsive pigments are used commercially as food colorants, anticancer drugs, as well as antibiotics and for cosmetic purposes. Materials and methods: Soil sample of Omidiyeh city was collected during the spring of 2014 and UV-resistant strain was isolated after primary and secondary screening. Then it was identified by molecular methods (16S rRNA gene sequencing. Antioxidant activity of pigment was evaluated by 2,2 -diphenyl-1-picryl hydrazyl (DPPH and the reducing power of pigments were analyzed by ferric chloride. Results: In this present study, new UV-resistant strain NM2 was isolated and by comparison of these 16S rRNA gene sequences to public database using the BLAST, the genus and species of the isolate was identified as Dietzia maris with 99% similarity. Extraction of pigment from isolated strain was carried out by methanol and acetone as solvents. The spectrum is characterized by maximum peak at 473 nm for pigment of NM2 strain. Antioxidant activity and the reducing ability of pigments increased by increasing their concentrations. NM2 strain pigment showed EC50 concentration of 3.30 mg/ml for DPPH free radical scavenging activity, and EC50 concentration of 28.46 µg/ml for reducing power. Discussion and conclusion: Isolation of natural resources of pigment is very important with high anti-oxidant activity. In the current study, pigment of UV-resistant bacteria demonstrated a strong antioxidant activity in vitro and pigment of these bacteria could play an important role in UV tolerance. Pigment of UV-resistant bacteria may be an appropriate source for antioxidative-related functional foods and the pharmaceutical

  13. Characterization and identification of newly isolated Acinetobacter baumannii strain serdang 1 for phenol removal

    Science.gov (United States)

    Yadzir, Z. H. M.; Shukor, M. Y.; Nazir, M. S.; Abdullah, M. A.

    2012-09-01

    A new indigenous bacterial strain from Malaysian soil contaminated with petroleum waste had been successfully isolated, characterized and identified for phenol removal. The gram negative bacteria showed 98% identity with Acinetobacter baumannii based on Biolog{trade mark, serif} Identification System and the determination of a partial 16S ribosomal RNA (rRNA) sequence. The isolate clustered with species belonging to Acinetobacter clade in a 16S rDNA-based neighbour-joining phylogenetic tree.

  14. Complete Genome Sequence of Photobacterium sp. Strain J15, Isolated from Seawater of Southwestern Johor, Malaysia.

    Science.gov (United States)

    Roslan, Noordiyanah Nadhirah; Sabri, Suriana; Oslan, Siti Nurbaya; Baharum, Syarul Nataqain; Leow, Thean Chor

    2016-07-28

    Here, we report the genome sequences of Photobacterium sp. strain J15, isolated from seawater in Johor, Malaysia, with the ability to produce lipase and asparaginase. The PacBio genome sequence analysis of Photobacterium sp. strain J15 generated revealed its potential in producing enzymes with different catalytic functions. Copyright © 2016 Roslan et al.

  15. ISOLATION OF THE GENOME SEQUENCE STRAIN MYCOBACTERIUM AVIUM 104 FROM MULTIPLE PATIENTS OVER A 17-YEAR PERIOD

    Science.gov (United States)

    The genome sequence strain 104 of the opportunistic pathogen Mycobacterium avium was isolated form an adult AIDS patient in Southern California in 1983. Isolates of non-paratuberculosis M. avium from 207 other patients in Southern California and elsewhere were examined for genoty...

  16. Inhibition of food-related bacteria by antibacterial substances produced by Pseudomonas sp. strains isolated from pasteurized milk

    Directory of Open Access Journals (Sweden)

    Ana Beatriz Ferreira Rangel

    2013-12-01

    Full Text Available In this work, the production of antimicrobial substances by strains of Pseudomonas sp. isolated from pasteurized milk and their potential action against food-related bacteria were investigated. Samples of pasteurized milk were purchased from arbitrarily chosen commercial establishments in the city of Rio de Janeiro, Brazil. Of the four samples analyzed, three presented several typical colonies of Pseudomonas. About 100 colonies were chosen and subjected to biochemical tests for confirmation of their identity. Eighteen strains of the Pseudomonas genus were identified and submitted to tests for the production of antimicrobial substances. Twelve strains (66.7% were identified as Pseudomonas fluorescens, four (22.2% as P. aeruginosa, one (5.5% as P. mendocina and one (5.5% as P. pseudoalcaligenes. Only two P. fluorescens strains were unable to produce any antimicrobial substance against any of the indicator strains tested. Most of the strains presented a broad spectrum of action, inhibiting reference and food-related strains such as Proteus vulgaris, Proteus mirabilis, Hafnia alvei, Yersinia enterocolitica, Escherichia coli and Salmonella typhi. Five antimicrobial substance-producing strains, which presented the broadest spectrum of action, were also tested against Staphylococcus aureus reference strains and 26 Staphylococcus sp. strains isolated from foods, some of which were resistant to antibiotics. The producer strains 8.1 and 8.3, both P. aeruginosa, were able to inhibit all the staphylococcal strains tested. The antimicrobial substances produced by strains 8.1 and 8.3 did not seem to be typical bacteriocins, since they were resistant to the three proteolytic enzymes tested. Experiments involving the characterization of these substances are being carried out in order to evaluate their biotechnological application.

  17. Genome Sequence of Aeribacillus pallidus Strain GS3372, an Endospore-Forming Bacterium Isolated in a Deep Geothermal Reservoir.

    Science.gov (United States)

    Filippidou, Sevasti; Jaussi, Marion; Junier, Thomas; Wunderlin, Tina; Jeanneret, Nicole; Regenspurg, Simona; Li, Po-E; Lo, Chien-Chi; Johnson, Shannon; McMurry, Kim; Gleasner, Cheryl D; Vuyisich, Momchilo; Chain, Patrick S; Junier, Pilar

    2015-08-27

    The genome of strain GS3372 is the first publicly available strain of Aeribacillus pallidus. This endospore-forming thermophilic strain was isolated from a deep geothermal reservoir. The availability of this genome can contribute to the clarification of the taxonomy of the closely related Anoxybacillus, Geobacillus, and Aeribacillus genera. Copyright © 2015 Filippidou et al.

  18. Characteristics of cytotoxic necrotizing factor and cytolethal distending toxin producing Escherichia coli strains isolated from meat samples in Northern Ireland.

    Science.gov (United States)

    Kadhum, H J; Ball, H J; Oswald, E; Rowe, M T

    2006-08-01

    Swabs collected from pig, lamb and beef carcasses and samples of pork, lamb and beef mince were cultured for Escherichia coli strains. Strains harbouring cytotoxic necrotizing factors (CNF1 and 2) and cytolethal distending toxins (CDT-I,-II,-III and -IV) were identified in plate cultures of the isolates by colony hybridization with labelled probes and multiplex PCR assays. Simplex and multiplex PCR assays were used to further characterize the isolates to determine the presence of P, S and F17 fimbriae as well as afimbrial adhesins and haemolysin. The serotype was also determined where possible. Thirty strains with the capacity to code for CNF (4), CDT (24) or both (2) were isolated and characterized, and a wide range of associated factor patterns was observed. The methods utilized were successful in demonstrating the detection of viable strains with potentially significant pathogenic factors from human food sources.

  19. Novel starters for old processes: use of Saccharomyces cerevisiae strains isolated from artisanal sourdough for craft beer production at a brewery scale.

    Science.gov (United States)

    Marongiu, Antonella; Zara, Giacomo; Legras, Jean-Luc; Del Caro, Alessandra; Mascia, Ilaria; Fadda, Costantino; Budroni, Marilena

    2015-01-01

    The deliberate inoculation of yeast strains isolated from food matrices such as wine or bread, could allow the transfer of novel properties to beer. In this work, the feasibility of the use of baker's yeast strains as starters for craft beer production has been evaluated at laboratory and brewery scale. Nine out of 12 Saccharomyces cerevisiae strains isolated from artisanal sourdoughs metabolized 2 % maltose, glucose and trehalose and showed growth rates and cell populations higher than those of the brewer's strain Safbrew-S33. Analysis of allelic variation at 12 microsatellite loci clustered seven baker's strains and Safbrew-S33 in the main group of bread isolates. Chemical analyses of beers produced at a brewery scale showed significant differences among the beers produced with the baker's strain S38 or Safbrew-S33, while no significant differences were observed when S38 or the brewer's strain Safbrew-F2 was used for re-fermentation. The sensory profile of beers obtained with S38 or the brewer's yeasts did not show significant differences, thus suggesting that baker's strains of S. cerevisiae could represent a reservoir of biodiversity for the selection of starter strains for craft beer production.

  20. Subtilomycin: A New Lantibiotic from Bacillus subtilis Strain MMA7 Isolated from the Marine Sponge Haliclona simulans

    Directory of Open Access Journals (Sweden)

    Teresa M. Barbosa

    2013-06-01

    Full Text Available Bacteriocins are attracting increased attention as an alternative to classic antibiotics in the fight against infectious disease and multidrug resistant pathogens. Bacillus subtilis strain MMA7 isolated from the marine sponge Haliclona simulans displays a broad spectrum antimicrobial activity, which includes Gram-positive and Gram-negative pathogens, as well as several pathogenic Candida species. This activity is in part associated with a newly identified lantibiotic, herein named as subtilomycin. The proposed biosynthetic cluster is composed of six genes, including protein-coding genes for LanB-like dehydratase and LanC-like cyclase modification enzymes, characteristic of the class I lantibiotics. The subtilomycin biosynthetic cluster in B. subtilis strain MMA7 is found in place of the sporulation killing factor (skf operon, reported in many B. subtilis isolates and involved in a bacterial cannibalistic behaviour intended to delay sporulation. The presence of the subtilomycin biosynthetic cluster appears to be widespread amongst B. subtilis strains isolated from different shallow and deep water marine sponges. Subtilomycin possesses several desirable industrial and pharmaceutical physicochemical properties, including activity over a wide pH range, thermal resistance and water solubility. Additionally, the production of the lantibiotic subtilomycin could be a desirable property should B. subtilis strain MMA7 be employed as a probiotic in aquaculture applications.

  1. Subtilomycin: A New Lantibiotic from Bacillus subtilis Strain MMA7 Isolated from the Marine Sponge Haliclona simulans

    Science.gov (United States)

    Phelan, Robert W.; Barret, Matthieu; Cotter, Paul D.; O’Connor, Paula M.; Chen, Rui; Morrissey, John P.; Dobson, Alan D. W.; O’Gara, Fergal; Barbosa, Teresa M.

    2013-01-01

    Bacteriocins are attracting increased attention as an alternative to classic antibiotics in the fight against infectious disease and multidrug resistant pathogens. Bacillus subtilis strain MMA7 isolated from the marine sponge Haliclona simulans displays a broad spectrum antimicrobial activity, which includes Gram-positive and Gram-negative pathogens, as well as several pathogenic Candida species. This activity is in part associated with a newly identified lantibiotic, herein named as subtilomycin. The proposed biosynthetic cluster is composed of six genes, including protein-coding genes for LanB-like dehydratase and LanC-like cyclase modification enzymes, characteristic of the class I lantibiotics. The subtilomycin biosynthetic cluster in B. subtilis strain MMA7 is found in place of the sporulation killing factor (skf) operon, reported in many B. subtilis isolates and involved in a bacterial cannibalistic behaviour intended to delay sporulation. The presence of the subtilomycin biosynthetic cluster appears to be widespread amongst B. subtilis strains isolated from different shallow and deep water marine sponges. Subtilomycin possesses several desirable industrial and pharmaceutical physicochemical properties, including activity over a wide pH range, thermal resistance and water solubility. Additionally, the production of the lantibiotic subtilomycin could be a desirable property should B. subtilis strain MMA7 be employed as a probiotic in aquaculture applications. PMID:23736764

  2. Isolation and sequence characterization of DNA-A genome of a new begomovirus strain associated with severe leaf curling symptoms of Jatropha curcas L.

    KAUST Repository

    Chauhan, Sushma

    2018-04-22

    Begomoviruses belong to the family Geminiviridae are associated with several disease symptoms, such as mosaic and leaf curling in Jatropha curcas. The molecular characterization of these viral strains will help in developing management strategies to control the disease. In this study, J. curcas that was infected with begomovirus and showed acute leaf curling symptoms were identified. DNA-A segment from pathogenic viral strain was isolated and sequenced. The sequenced genome was assembled and characterized in detail. The full-length DNA-A sequence was covered by primer walking. The genome sequence showed the general organization of DNA-A from begomovirus by the distribution of ORFs in both viral and anti-viral strands. The genome size ranged from 2844 bp–2852 bp. Three strains with minor nucleotide variations were identified, and a phylogenetic analysis was performed by comparing the DNA-A segments from other reported begomovirus isolates. The maximum sequence similarity was observed with Euphorbia yellow mosaic virus (FN435995). In the phylogenetic tree, no clustering was observed with previously reported begomovirus strains isolated from J. curcas host. The strains isolated in this study belong to new begomoviral strain that elicits symptoms of leaf curling in J. curcas. The results indicate that the probable origin of the strains is from Jatropha mosaic virus infecting J. gassypifolia. The strains isolated in this study are referred as Jatropha curcas leaf curl India virus (JCLCIV) based on the major symptoms exhibited by host J. curcas.

  3. Genomic and Proteomic Characterization of Bacteriocin-Producing Leuconostoc mesenteroides Strains Isolated from Raw Camel Milk in Two Southwest Algerian Arid Zones

    Directory of Open Access Journals (Sweden)

    Zineb Benmechernene

    2014-01-01

    Full Text Available Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS which allowed for the identification of 2 mass peaks 6242 m/z and 5118 m/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk.

  4. Genomic and proteomic characterization of bacteriocin-producing Leuconostoc mesenteroides strains isolated from raw camel milk in two southwest Algerian arid zones.

    Science.gov (United States)

    Benmechernene, Zineb; Fernández-No, Inmaculada; Quintela-Baluja, Marcos; Böhme, Karola; Kihal, Mebrouk; Calo-Mata, Pilar; Barros-Velázquez, Jorge

    2014-01-01

    Information on the microbiology of camel milk is very limited. In this work, the genetic characterization and proteomic identification of 13 putative producing bacteriocin Leuconostoc strains exhibiting antilisterial activity and isolated from camel milk were performed. DNA sequencing of the 13 selected strains revealed high homology among the 16S rRNA genes for all strains. In addition, 99% homology with Leuconostoc mesenteroides was observed when these sequences were analysed by the BLAST tool against other sequences from reference strains deposited in the Genbank. Furthermore, the isolates were characterized by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDITOF MS) which allowed for the identification of 2 mass peaks 6242 m/z and 5118 m/z that resulted to be specific to the species L. mesenteroides. Remarkably, the phyloproteomic tree provided more intraspecific information of L. mesenteroides than phylogenetic analysis. Accordingly, phyloproteomic analysis grouped L. mesenteroides strains into different subbranches, while all L. mesenteroides isolates were grouped in the same branch according to phylogenetic analysis. This study represents, to our knowledge, the first report on the use of MALDI-TOF MS on the identification of LAB isolated from camel milk.

  5. RAPD Analysis and Antibiotic Susceptibility for Mycobacterium tuberculosis Strains Isolated from Different Locations in Egypt

    Directory of Open Access Journals (Sweden)

    Ali, A. M.

    2011-01-01

    Full Text Available The routine identification of mycobacterial strains isolated from patients in different locations in Egypt was confirmed by specific DNA fragment amplification. The susceptibilities of 72 Mycobacterium tuberculosis strains against the four antibiotics used in tuberculosis treatment (Isoniazid, INH; Rifampicin, Rif; Streptomycin, St and Ethambutol, E were examined. Our results indicated that, multi drug resistant tuberculosis (MDR-TB represents about 19.5% of the tested strains, whereas sensitive strains represented 26.4%. The genetic polymorphism of the tested strains was examined using RAPD analysis. Six selected strains represent the different antibiotic susceptibility groups were examined using RAPD fingerprinting. No difference between the strains was recorded using the RFLP analysis of amplified specific fragment. The discrimination power of RAPD analysis was inadequate to clarify the genetic correlation between the tested strains. MDR-TB was approximately double time in 2008 compared with the value in 2007. Most of the new MDRTB was correlated with resident dense population regions.

  6. Characterization of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients in the Zagreb region

    Directory of Open Access Journals (Sweden)

    Branka Bedenić,

    2010-02-01

    Full Text Available Aim To determine the prevalence of ESBL-producing Escherichia coli and Klebsiella pneumoniae strains isolated from urine of nonhospitalized patients during a three-year period, to determine their antibiotic susceptibility, investigate the transfer of ESBL genes with cotransfer of resistance and to characterize isolated beta-lactamases. Methods Antimicrobial susceptibility was determined by disk diffusion and broth microdilution methods. The double-disk test was used for ESBL detection. Transfer of resistance was performed by broth mating method and characterization of isolated beta-lactamases by polymerase chain reaction. Results The prevalence of ESBL-producing E. coli was 1.5% and of K. pneumoniae 4.1% with its different distribution according to patients`age and gender. ESBL-producing K. pneumoniae showed high resistance rates to aminoglycosides, cotrimoxazole, nitrofurantoin and quinolones while ESBL-producing E. coli isolates, with exception of high aminoglycoside resistance, showed low resistance rates to other antibiotics. Successful conjugation of ESBL genes was obtained with 25% E. coli and 76.2% K. pneumoniae strains. Comparing to E. coli, K. pneumoniae strains showed higher rates of aminoglycosideand cotrimoxazole resistance cotransfer. Beta-lactamases of investigated strains belonged to TEM, SHV and CTX-M families.Conclusion The existence of multiple-resistant ESBL-producing E. coli and K. pneumoniae strains was confirmed in observed outpatient population. ESBL-producing K. pneumoniae isolates, in contrast toESBL-producing E. coli, showed higher resistance rates to non-beta-lactam antibiotics, probably caused by cotransfer of resistance genes located on the same plasmid as ESBL genes. It is important to monitor the prevalence of such strains and their possible spreading in the outpatient population of the Zagreb region

  7. Probiotic properties of Lactobacillus strains isolated from the feces of breast-fed infants and Taiwanese pickled cabbage.

    Science.gov (United States)

    Wang, Chung-Yi; Lin, Pei-Rong; Ng, Chang-Chai; Shyu, Yuan-Tay

    2010-12-01

    This study assessed potential probiotic Lactobacillus strains isolated from the feces of breast-fed infants and from Taiwanese pickled cabbage for their possible use in probiotic fermented foods by evaluating their (i) in vitro adhesive ability, resistance to biotic stress, resistance to pathogenic bacteria, and production of β-galactosidase; (ii) milk technological properties; and (iii) in vivo adhesive ability, intestinal survival and microbial changes during and after treatment. Five Lactobacillus isolates identified as Lactobacillus reuteri F03, Lactobacillus paracasei F08, Lactobacillus rhamnosus F14, Lactobacillus plantarum C06, and Lactobacillus acidophilus C11 that showed resistance to gastric juice and bile salts were selected for further evaluation of their probiotic properties. All the strains demonstrated the ability to adhere to Caco-2 cells, particularly, strain L. plantarum C06 and L. reuteri F03 showed satisfactory abilities, which were similar to that of the reference strain L. rhamnosus GG. The strains L. paracasei F08 and L. acidophilus C11 had the highest β-galactosidase activity. Most of the strains were resistant to aminoglycosides and vancomycin but sensitive to ampicillin, erythromycin, and penicillin. All the 5 strains elicited antibacterial activity against both Gram-positive (Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus) and -negative (Escherichia coli and Salmonella enterica) pathogens. Moreover, the strains L. reuteri F03, L. paracasei F08, and L. plantarum C06 could grow rapidly in milk without nutrient supplementation and reached 10⁸ cfu/mL after 24 h of fermentation at 37 °C. The viable cell counts of the 3 strains remained above 10⁷ cfu/mL after 21 d of storage at 4 °C. In the animal feeding trial, the number of intestinal lactobacilli increased significantly after administration of milk fermented with the 3 strains, and the counts of fecal coliforms and Clostridium perfringens were markedly reduced

  8. Stabilization of kerosene/water emulsions using bioemulsifiers obtained by fermentation of hemicellulosic sugars with Lactobacillus pentosus.

    Science.gov (United States)

    Portilla-Rivera, Oscar Manuel; Torrado, Ana María; Domínguez, José Manuel; Moldes, Ana Belén

    2010-09-22

    The results of the present study show that Lactobacillus pentosus can produce extracellular bioemulsifiers by utilizing hemicellulosic sugars from grape marc as a source of carbon. The effectiveness of these bioemulsifiers (LPEM) was studied by preparing kerosene/water (K/W) emulsions in the presence and absence of these emulsifiers. Various parameters such as relative emulsion volume (EV), stabilizing capacity (ES), viscosity, and droplet size of K/W emulsions were measured. The EV values for K/W emulsions stabilized by concentrated LPEM were approximately 74.5% after 72 h of emulsion formation, with ES values of 97%. These values were higher than those obtained with dodecyl sodium sulfate as emulsifier (EV=62.3% and ES=87.7%). Additionally, K/W emulsions stabilized by LPEM produced polydisperse emulsions containing droplets of radius between 10 and 40 μm, which were smaller than those obtained for K/W emulsions without LPEM (droplet radius=60-100 μm). Moreover, the viscosity values of the K/W emulsions without and with LPEM were approximately 236 and 495 cP, respectively.

  9. Draft Genome Sequences of Pseudomonas aeruginosa B3 Strains Isolated from a Cystic Fibrosis Patient Undergoing Antibiotic Chemotherapy

    DEFF Research Database (Denmark)

    Marvig, Rasmus Lykke; Jochumsen, Nicholas; Johansen, Helle Krogh

    2013-01-01

    Pseudomonas aeruginosa frequently establishes chronic infections in the airways of patients suffering from cystic fibrosis (CF). Here, we report the draft genome sequences of four P. aeruginosa B3 strains isolated from a chronically infected CF patient undergoing antibiotic chemotherapy.......Pseudomonas aeruginosa frequently establishes chronic infections in the airways of patients suffering from cystic fibrosis (CF). Here, we report the draft genome sequences of four P. aeruginosa B3 strains isolated from a chronically infected CF patient undergoing antibiotic chemotherapy....

  10. Potential probiotic attributes of a new strain of Bacillus coagulans CGMCC 9951 isolated from healthy piglet feces.

    Science.gov (United States)

    Gu, Shao-Bin; Zhao, Li-Na; Wu, Ying; Li, Shi-Chang; Sun, Jian-Rui; Huang, Jing-Fang; Li, Dan-Dan

    2015-06-01

    A new strain of Bacillus coagulans CGMCC 9551, which has a broad range of antibacterial activities against six main pathogenic bacteria including Escherichia coli O8, Staphylococcus aureus, Salmonella enterica subsp. enterica serovar enteritidis, Streptococcus suis, Listeria monocytogenes and Pasteurella multocida, was isolated from healthy piglet feces. In adhesion assay, the isolate exhibited a stronger adhesion to pig intestinal mucus than that of B. subtilis JT143 and L. acidophilus LY24 respectively isolated from BioPlus(®)2B and FloraFIT(®) Probiotics (P coagulans CGMCC 9551 was reduced by only 20% at 4 h exposure under 0.9% w/v bile salt. The strain was fully resistant to pH 2 for 2 h with 90.1 ± 3.5% survival and susceptible to 15 antibiotics commonly used in veterinary medicine. Additionally, the bacteria showed amylase, protease and cellulase activities. The safety assessment demonstrated the lack of toxicity potential in B. coagulans CGMCC 9551 by ligated rabbit ileal loop assay, acute and subchronic toxicity test. These results implied that that the new strain of B. coagulans CGMCC 9951 isolated from healthy piglet feces has promising probiotic characteristics and offers desirable opportunities for its successful commercialization as one excellent candidate probiotic.

  11. Biocontrol of Fusarium Crown and Root Rot and Promotion of Growth of Tomato by Paenibacillus Strains Isolated from Soil

    Science.gov (United States)

    Xu, Sheng Jun

    2014-01-01

    In this study, bacterial strains were isolated from soils from 30 locations of Samcheok, Gangwon province. Of the isolated strains, seven showed potential plant growth promoting and antagonistic activities. Based on cultural and morphological characterization, and 16S rRNA gene sequencing, these strains were identified as Paenibacillus species. All seven strains produced ammonia, cellulase, hydrocyanic acid, indole-3-acetic acid, protease, phosphatase, and siderophores. They also inhibited the mycelial growth of Fusarium oxysporum f. sp. radicis-lycopersici in vitro. The seven Paenibacillus strains enhanced a range of growth parameters in tomato plants under greenhouse conditions, in comparison with non-inoculated control plants. Notably, treatment of tomato plants with one identified strain, P. polymyxa SC09-21, resulted in 80.0% suppression of fusarium crown and root rot under greenhouse conditions. The plant growth promoting and antifungal activity of P. polymyxa SC09-21 identified in this study highlight its potential suitability as a bioinoculant. PMID:25071385

  12. Identification of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from burn patients by multiplex PCR.

    Science.gov (United States)

    Montazeri, Effat Abbasi; Khosravi, Azar Dokht; Jolodar, Abbas; Ghaderpanah, Mozhgan; Azarpira, Samireh

    2015-05-01

    Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) as important human pathogens are causes of nosocomial infections worldwide. Burn patients are at a higher risk of local and systemic infections with these microorganisms. A screening method for MRSA by using a multiplex polymerase chain reaction (PCR) targeting the 16S ribosomal RNA (rRNA), mecA, and nuc genes was developed. The aim of the present study was to investigate the potential of this PCR assay for the detection of MRSA strains in samples from burn patients. During an 11-month period, 230 isolates (53.11%) of Staphylococcus spp. were collected from burn patients. The isolates were identified as S. aureus by using standard culture and biochemical tests. DNA was extracted from bacterial colonies and multiplex PCR was used to detect MRSA and MRCoNS strains. Of the staphylococci isolates, 149 (64.9%) were identified as S. aureus and 81 (35.21%) were described as CoNS. Among the latter, 51 (62.97%) were reported to be MRCoNS. From the total S. aureus isolates, 132 (88.6%) were detected as MRSA and 17 (11.4%) were methicillin-susceptible S. aureus (MSSA). The presence of the mecA gene in all isolates was confirmed by using multiplex PCR as a gold standard method. This study presented a high MRSA rate in the region under investigation. The 16S rRNA-mecA-nuc multiplex PCR is a good tool for the rapid characterization of MRSA strains. This paper emphasizes the need for preventive measures and choosing effective antimicrobials against MRSA and MRCoNS infections in the burn units. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  13. Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China.

    Science.gov (United States)

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; Guan, Hong; Li, Machao; Zhu, Bingqing; Shao, Zhujun

    2014-04-01

    Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea.

  14. Relevance of the clustered regularly interspaced short palindromic repeats of Enterococcus faecalis strains isolated from retreatment root canals on periapical lesions, resistance to irrigants and biofilms.

    Science.gov (United States)

    Tong, Zhongchun; Du, Yu; Ling, Junqi; Huang, Lijia; Ma, Jinglei

    2017-12-01

    A high prevalence of Enterococcus faecalis ( E. faecalis ) is observed in teeth with root canal treatment failures. Clustered regularly interspaced short palindromic repeats (CRISPR) are widely distributed in prokaryotes that have adaptive immune systems against mobile elements, including pathogenic genes. The present study investigated the relevance of the CRISPR in E. faecalis strains isolated from retreated root canals on biofilms, periapical lesions and drug resistance. A total of 20 E. faecalis strains were extracted from the root canals of teeth referred for root canal retreatment. CRISPR-Cas loci were identified by two pairs of relevant primers and polymerase chain reaction. The susceptibility of the 20 isolated strains to intracanal irrigants was evaluated by 1- and 5-minute challenges with a mixture of a tetracycline isomer, an acid and a detergent (MTAD), 2% chlorhexidine (CHX) and 5.25% sodium hypochlorite (NaOCl). The microtiter plate assay and crystal violet staining were used to compare the biofilm formation of the E. faecalis isolate strains. Out of the 20 E. faecalis isolate strains, 5 strains that lacked CRISPR-cas determinants exhibited significant periapical lesions. Among the 15 strains containing CRISPR-cas determinants, 8 were isolated from root canals with inadequate fillings and 7 were isolated from root canals without any fillings. The five strains lacking CRISPR-cas loci were observed to be more resistant to MTAD and 2% CHX than the 15 strains that had CRISPR-cas loci. All of the strains exhibited the same susceptibility to 5.25% NaOCl. Furthermore, the 5 strains lacking CRISPR-cas determinants generated more biofilm than the other 15 strains. Thus, the results of the present study suggested that E. faecalis root canal isolates lacking CRISPR-cas exhibit higher resistance to intracanal irrigants, stronger biofilm formation and generate significant periapical lesions.

  15. Isolation and characterization of biosurfactant-producing Alcanivorax strains: hydrocarbon accession strategies and alkane hydroxylase gene analysis.

    Science.gov (United States)

    Olivera, Nelda L; Nievas, Marina L; Lozada, Mariana; Del Prado, Guillermo; Dionisi, Hebe M; Siñeriz, Faustino

    2009-01-01

    Biosurfactant-producing bacteria belonging to the genera Alcanivorax, Cobetia and Halomonas were isolated from marine sediments with a history of hydrocarbon exposure (Aristizábal and Gravina Peninsulas, Argentina). Two Alcanivorax isolates were found to form naturally occurring consortia with strains closely related to Pseudomonas putida and Microbacterium esteraromaticum. Alkane hydroxylase gene analysis in these two Alcanivorax strains resulted in the identification of two novel alkB genes, showing 86% and 60% deduced amino acid sequence identity with those of Alcanivorax sp. A-11-3 and Alcanivorax dieselolei P40, respectively. In addition, a gene homologous to alkB2 from Alcanivorax borkumensis was present in one of the strains. The consortium formed by this strain, Alcanivorax sp. PA2 (98.9% 16S rRNA gene sequence identity with A. borkumensis SK2(T)) and P. putida PA1 was characterized in detail. These strains form cell aggregates when growing as mixed culture, though only PA2 was responsible for biosurfactant activity. During exponential growth phase of PA2, cells showed high hydrophobicity and adherence to hydrocarbon droplets. Biosurfactant production was only detectable at late growth and stationary phases, suggesting that it is not involved in initiating oil degradation and that direct interfacial adhesion is the main hydrocarbon accession mode of PA2. This strain could be useful for biotechnological applications due to its biosurfactant production, catabolic and aggregation properties.

  16. Isolation of thermophilic Desulfotomaculum strains with methanol and sulphite from solfataric mud pools, and characterization of Desulfotomaculum solfataricum

    NARCIS (Netherlands)

    Goorissen, H.P.; Stams, A.J.M.; Hansen, T.A.

    2003-01-01

    Four strains of thermophilic, endospore-forming, sulfate-reducing bacteria were enriched and isolated from hot solfataric fields in the Krafla area of north-east Iceland, using methanol and sulfite as substrates. Morphologically, these strains resembled thermophilic Desulfotomaculum species. The

  17. [VNTR-genotyping of Vibrio cholerae strains isolated from objects in the territory of Russian Federation in 2012].

    Science.gov (United States)

    Vodop'ianov, A S; Mazrukho, A B; Vodop'ianov, S O; Mishan'kin, B N; Kruglikov, V D; Apkhangel'skaia, I V; Oleĭnikov, I P; Zubkova, D A; Monakhova, E V; Grigorenko, L V

    2014-01-01

    VNTR-typing of Vibrio cholerae strains isolated in the territory of Russian Federation in 2012. 71 Vibrio cholerae O3 and 3 V cholerae O1/O139 strains were used in the study. Genotyping was performed by using PCR for 5 VNTR-loci. Multilocus VNTR-typing allowed to group the strains into 31 VNTR-genotypes. Genotypes were divided among 10 discrete clusters by results of a cluster analysis. The presence of tcpA gene is clearly linked with the presence of VcB locus. Each geographic region was characterized by their own VNTR-genotypes. In the course of the carried out VNTR-genotyping of V. cholerae isolated in 2012, 2 types of vibrio population formation were detected. A geographic attachment to specific regions was characteristic for most of the genotypes.

  18. Comparative Transcriptomics of Bacillus mycoides Strains in Response to Potato-Root Exudates Reveals Different Genetic Adaptation of Endophytic and Soil Isolates.

    Science.gov (United States)

    Yi, Yanglei; de Jong, Anne; Frenzel, Elrike; Kuipers, Oscar P

    2017-01-01

    Plant root secreted compounds alter the gene expression of associated microorganisms by acting as signal molecules that either stimulate or repel the interaction with beneficial or harmful species, respectively. However, it is still unclear whether two distinct groups of beneficial bacteria, non-plant-associated (soil) strains and plant-associated (endophytic) strains, respond uniformly or variably to the exposure with root exudates. Therefore, Bacillus mycoides , a potential biocontrol agent and plant growth-promoting bacterium, was isolated from the endosphere of potatoes and from soil of the same geographical region. Confocal fluorescence microscopy of plants inoculated with GFP-tagged B. mycoides strains showed that the endosphere isolate EC18 had a stronger plant colonization ability and competed more successfully for the colonization sites than the soil isolate SB8. To dissect these phenotypic differences, the genomes of the two strains were sequenced and the transcriptome response to potato root exudates was compared. The global transcriptome profiles evidenced that the endophytic isolate responded more pronounced than the soil-derived isolate and a higher number of significant differentially expressed genes were detected. Both isolates responded with the alteration of expression of an overlapping set of genes, which had previously been reported to be involved in plant-microbe interactions; including organic substance metabolism, oxidative reduction, and transmembrane transport. Notably, several genes were specifically upregulated in the endosphere isolate EC18, while being oppositely downregulated in the soil isolate SB8. These genes mainly encoded membrane proteins, transcriptional regulators or were involved in amino acid metabolism and biosynthesis. By contrast, several genes upregulated in the soil isolate SB8 and downregulated in the endosphere isolate EC18 were related to sugar transport, which might coincide with the different nutrient availability

  19. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    OpenAIRE

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different...

  20. Characterization of newly isolated Lactobacillus delbrueckii-like strain MF-07 isolated from chicken and its role in isoflavone biotransformation.

    Science.gov (United States)

    Iqbal, Muhammad Farooq; Zhu, Wei-Yun

    2009-02-01

    Cecal microbiota of chicken was screened for bacteria involved in the biotransformation of isoflavones. A new facultative anaerobic bacterium, capable of deglycosylation of the isoflavone genistin, was isolated and identified as a Lactobacillus delbrueckii-like strain. The isolate MF-07 was Gram-positive, facultatively anaerobic, catalase negative, non-spore-forming, nonmotile and a straight rod. The polyphasic taxonomic data, along with 16S rRNA gene sequence comparison, demonstrated that the isolate MF-07 was most closely related to L. delbrueckii group of the Lactobacillus genus. Considerable amounts of genistein were accumulated with genistin as a substrate within the first 12 h of fermentation. Formononetin and daidzein were not metabolized. The influence of several carbon sources on the growth of the isolate MF-07 and biotransformation of genistin was also investigated. This is the first study in which an anaerobic Lactobacillus bacterium from the chicken intestinal tract that metabolizes genistin to produce its bioactive metabolite was identified and characterized.

  1. Molecular characterization of Plum pox virus Rec isolates from Russia suggests a new insight into evolution of the strain.

    Science.gov (United States)

    Chirkov, Sergei; Ivanov, Peter; Sheveleva, Anna; Kudryavtseva, Anna; Mitrofanova, Irina

    2018-04-01

    Field isolates of Plum pox virus (PPV), belonging to the strain Rec, have been found for the first time in Russia. Full-size genomes of the isolates K28 and Kisl-1pl from myrobalan and plum, respectively, were sequenced on the 454 platform. Analysis of all known PPV-Rec complete genomes using the Recombination Detection Program (RDP4) revealed yet another recombination event in the 5'-terminal region. This event was detected by seven algorithms, implemented in the RDP4, with statistically significant P values and supported by a phylogenetic analysis with the bootstrap value of 87%. A putative PPV-M-derived segment, encompassing the C-terminus of the P1 gene and approximately two-thirds of the HcPro gene, is bordered by breakpoints at positions 760-940 and 1838-1964, depending on the recombinant isolate. The predicted 5'-distal breakpoint for the isolate Valjevka is located at position 2804. The Dideron (strain D) and SK68 (strain M) isolates were inferred as major and minor parents, respectively. Finding of another recombination event suggests more complex evolutionary history of PPV-Rec than previously assumed. Perhaps the first recombination event led to the formation of a PPV-D variant harboring the PPV-M-derived fragment within the 5'-proximal part of the genome. Subsequent recombination of its descendant with PPV-M in the 3'-proximal genomic region resulted in the emergence of the evolutionary successful strain Rec.

  2. STUDY ON THE ANTIBIOTIC-RESISTANCE IN STRAINS OF SALMONELLA ISOLATES IN FOOD FROM 2003 TO 2010

    Directory of Open Access Journals (Sweden)

    F. Capuano

    2012-08-01

    Full Text Available A survey on the antibiotics resistance on salmonella strains of food origin was carried out. Four hundred thirty five different strains of Salmonella detected during eight years since 2003 were tested with the protocols of the National Committee for Clinical Laboratory Standard (NCCLS. One hundred twenty Salmonella strains were of cow origin, 166 from swine, 92 from poultry and the remaining 57 from shellfish. Starting from 2007 a reduction in the resistance was evident on the total isolates.

  3. Isolation and characterization of mutant strains of Escherichia coli altered in H2 metabolism

    International Nuclear Information System (INIS)

    Lee, J.H.; Patel, P.; Sankar, P.; Shanmugam, K.T.

    1985-01-01

    A positive selection procedure is described for the isolation of hydrogenase-defective mutant strains of Escherichia coli. Mutant strains isolated by this procedure can be divided into two major classes. Class II mutants produced hydrogenase activity (determined by using a tritium-exchange assay) and formate hydrogenlyase activity but lacked the ability to reduce benzyl viologen or fumarate with H 2 as the electron donor. Class I mutants failed to produce active hydrogenase and hydrogenase-dependent activities. All the mutant strains produced detectable levels of formate dehydrogenase-1 and -2 and fumarate reductase. The mutation in class I mutants mapped near 65 min of the E. coli chromosome, whereas the mutation in class II mutants mapped between srl and cys operons (58 and 59 min, respectively) in the genome. The class II Hyd mutants can be further subdivided into two groups (hydA and hydB) based on the cotransduction characteristics with cys and srl. These results indicate that there are two hyd operons and one hup operon in the E. coli chromosome. The two hyd operons are needed for the production of active hydrogenase, and all three are essential for hydrogen-dependent growth of the cell

  4. The potential pathogenicity of chlorhexidine-sensitive Acanthamoeba strains isolated from contact lens cases from asymptomatic individuals in Tenerife, Canary Islands, Spain.

    Science.gov (United States)

    Martín-Navarro, Carmen M; Lorenzo-Morales, Jacob; Cabrera-Serra, M Gabriela; Rancel, Fernando; Coronado-Alvarez, Nieves M; Piñero, José E; Valladares, Basilio

    2008-11-01

    Pathogenic strains of the genus Acanthamoeba are causative agents of a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. The prevalence of this infection has risen in the past 20 years, mainly due to the increase in number of contact lens wearers. In this study, the prevalence of Acanthamoeba in a risk group constituted by asymptomatic contact lens wearers from Tenerife, Canary Islands, Spain, was evaluated. Contact lenses and contact lens cases were analysed for the presence of Acanthamoeba isolates. The isolates' genotypes were also determined after rDNA sequencing. The pathogenic potential of the isolated strains was subsequently established using previously described molecular and biochemical assays, which allowed the selection of three strains with high pathogenic potential. Furthermore, the sensitivity of these isolates against two standard drugs, ciprofloxacin and chlorhexidine, was analysed. As the three selected strains were sensitive to chlorhexidine, its activity and IC(50) were evaluated. Chlorhexidine was found to be active against these strains and the obtained IC(50) values were compared to the concentrations of this drug present in contact lens maintenance solutions. It was observed that the measured IC(50) was higher than the concentration found in these maintenance solutions. Therefore, the ineffectiveness of chlorhexidine-containing contact lens maintenance solutions against potentially pathogenic strains of Acanthamoeba is demonstrated in this study.

  5. Potential antagonism of some Trichoderma strains isolated from Moroccan soil against three phytopathogenic fungi of great economic importance

    Directory of Open Access Journals (Sweden)

    Wafaa MOKHTARI

    2017-09-01

    Full Text Available In this study, 17 Trichoderma strains were isolated from different soils (crop fields and Argan forests in Morocco. Purified monospore cultures were identified using molecular methods and tested for their potential antagonism against three phytopathogenic fungi (Fusarium oxyxporum, verticillium dahlia and rhizoctonia solani. After DNA extraction, translation elongation factor (tef1 was amplified in extracts of 17 strains, sequenced and compared with their ex-types. As a result, three species were identified among the strains, which clustered in two different subclades of Trichoderma: the species T. afroharzianum, and T. guizhouense belong to the Harzianum clade, while T. longibrachiatum belongs to the Longibrachiatum clade. Investigation of potential antagonistic effects of these strains against the soil-borne phytopathogens F. oxysporum, R. solani and V. dahliae was conducted in a dual culture plate assay, using 17 promising Trichoderma strains that have been selected based on a polymerase chain reaction (PCR screening approach. In vitro, Trichoderma isolates showed effective antagonistic performance by decreasing soil borne pathogens mycelium radial growth. Trichoderma afroharzianum showed the highest Percentage of Radial Inhibition Growth (PRIG %. The highest PRIG% = 98% was for 8A2.3 isolate against R. solani and the lowest PRIG%= 67% for T9i10 against F. oxysporum. On the other hand, T9i12, which is T. reesei species, led to a high radial inhibition of pathogens’ mycelium.

  6. Esterase activities of intracellular extracts of wild strains of lactic acid bacteria isolated from Serra da Estrela cheese

    OpenAIRE

    Macedo, Angela C.; Tavares, Tânia G.; Malcata, F. Xavier

    2003-01-01

    Lactococcus lactis subsp. lactis strain ESB110019 and Lactobacillus plantarum strain ESB5004, novel strains that were previously isolated from the wild adventitious microflora of certified Serra da Estrela cheeses, were assayed for esterase activity using, as substrates, ortho- and para-nitrophenyl derivatives of fatty acids. Both strains preferentially hydrolyzed short-chain fatty acids; L. lactis ESB110019 exhibited a stronger esterase activity than Lb. plantarum ESB5004 and cleaved the p-n...

  7. Characteristics of Shigatoxin-Producing Escherichia coli Strains Isolated during 2010–2014 from Human Infections in Switzerland

    Directory of Open Access Journals (Sweden)

    Lisa Fierz

    2017-08-01

    Full Text Available Objectives: The aim of this study was to characterize a collection of 95 Shigatoxin-producing E.coli (STEC isolated from human patients in Switzerland during 2010–2014.Methods: We performed O and H serotyping and molecular subtyping.Results: The five most common serogroups were O157, O145, O26, O103, and O146. Of the 95 strains, 35 (36.8% carried stx1 genes only, 43 strains (45.2% carried stx2 and 17 (17.9% harbored combinations of stx1 and stx2 genes. Stx1a (42 strains and stx2a (32 strains were the most frequently detected stx subtypes. Genes for intimin (eae, hemolysin (hly, iron-regulated adhesion (iha, and the subtilase cytotoxin subtypes subAB1, subAB2-1, subAB2-2, or subAB2-3 were detected in 70.5, 83.2, 74.7, and 20% of the strains, respectively. Multilocus sequence typing assigned the majority (58.9% of the isolates to five different clonal complexes (CC, 11, 32, 29, 20, and 165, respectively. CC11 included all O157:[H7] and O55:[H7] isolates. CC32 comprised O145:[H28] isolates, and O145:[H25] belonged to sequence type (ST 342. CC29 contained isolates of the O26:[H11], O111:[H8] and O118:[Hnt] serogroups, and CC20 encompassed isolates of O51:H49/[Hnt] and O103:[H2]. CC165 included isolates typed O80:[H2]-ST301, all harboring stx2d, eae-ξ, hly, and 66.7% additionally harboring iha. All O80:[H2]-ST301 strains harbored at least 7 genes carried by pS88, a plasmid associated with extraintestinal virulence. Compared to data from Switzerland from the years 2000–2009, an increase of the proportion of non-O157 STEC infections was observed as well as an increase of infections due to STEC O146. By contrast, the prevalence of the highly virulent German clone STEC O26:[H11]-ST29 decreased from 11.3% during 2000–2009 to 1.1% for the time span 2010–2014. The detection of O80:[H2]-ST301 harboring stx2d, eae-ξ, hly, iha, and pS88 related genes suggests an ongoing emergence in Switzerland of an unusual, highly pathogenic STEC serotype

  8. Draft Genome Sequence of MCPA-Degrading Sphingomonas sp. Strain ERG5, Isolated from a Groundwater Aquifer in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Tue Kjærgaard; Kot, Witold; Sørensen, Sebastian R

    2015-01-01

    Sphingomonas sp. strain ERG5 was isolated from a bacterial community, originating from a groundwater aquifer polluted with low pesticide concentrations. This bacterium degrades 2-methyl-4-chlorophenoxyacetic acid (MCPA) in a wide spectrum of concentrations and has been shown to function in bioaug......Sphingomonas sp. strain ERG5 was isolated from a bacterial community, originating from a groundwater aquifer polluted with low pesticide concentrations. This bacterium degrades 2-methyl-4-chlorophenoxyacetic acid (MCPA) in a wide spectrum of concentrations and has been shown to function...

  9. Resistance Pattern and Molecular Characterization of Enterotoxigenic Escherichia coli (ETEC Strains Isolated in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Yasmin A Begum

    Full Text Available Enterotoxigenic Escherichia coli (ETEC is a common cause of bacterial infection leading to acute watery diarrhea in infants and young children as well as in travellers to ETEC endemic countries. Ciprofloxacin is a broad-spectrum antimicrobial agent nowadays used for the treatment of diarrhea. This study aimed to characterize ciprofloxacin resistant ETEC strains isolated from diarrheal patients in Bangladesh.A total of 8580 stool specimens from diarrheal patients attending the icddr,b Dhaka hospital was screened for ETEC between 2005 and 2009. PCR and Ganglioside GM1- Enzyme Linked Immuno sorbent Assay (ELISA was used for detection of Heat labile (LT and Heat stable (ST toxins of ETEC. Antimicrobial susceptibilities for commonly used antibiotics and the minimum inhibitory concentration (MIC of nalidixic acid, ciprofloxacin and azithromycin were examined. DNA sequencing of representative ciprofloxacin resistant strains was performed to analyze mutations of the quinolone resistance-determining region of gyrA, gyrB, parC and parE. PCR was used for the detection of qnr, a plasmid mediated ciprofloxacin resistance gene. Clonal variations among ciprofloxacin resistant (CipR and ciprofloxacin susceptible (CipS strains were determined by Pulsed-field gel electrophoresis (PFGE.Among 1067 (12% ETEC isolates identified, 42% produced LT/ST, 28% ST and 30% LT alone. Forty nine percent (n = 523 of the ETEC strains expressed one or more of the 13 tested colonization factors (CFs as determined by dot blot immunoassay. Antibiotic resistance of the ETEC strains was observed as follows: ampicillin 66%, azithromycin 27%, ciprofloxacin 27%, ceftriazone 13%, cotrimaxazole 46%, doxycycline 44%, erythromycin 96%, nalidixic acid 83%, norfloxacin 27%, streptomycin 48% and tetracycline 42%. Resistance to ciprofloxacin increased from 13% in 2005 to 34% in 2009. None of the strains was resistant to mecillinam. The MIC of the nalidixic acid and ciprofloxacin of representative

  10. Variations in biofilm formation, desiccation resistance and Benzalkonium chloride susceptibility among Listeria monocytogenes strains isolated in Canada.

    Science.gov (United States)

    Piercey, Marta J; Ells, Timothy C; Macintosh, Andrew J; Truelstrup Hansen, Lisbeth

    2017-09-18

    Listeria monocytogenes is a pathogenic foodborne microorganism noted for its ability to survive in the environment and food processing facilities. Survival may be related to the phenotype of individual strains including the ability to form biofilms and resist desiccation and/or sanitizer exposure. The objectives of this research were to compare 14 L. monocytogenes strains isolated from blood (3), food (6) and water (5) with respect to their benzalkonium chloride (BAC) sensitivity, desiccation resistance, and ability to form biofilm. Correlations were tested between those responses, and the presence of the SSI-1 (Stress Survival Islet) and LGI1/CC8 (Listeria Genomic Island 1 in a clonal complex 8 background) genetic markers. Genetic sequences from four strains representing different phenotypes were also probed for predicted amino acid differences in biofilm, desiccation, and membrane related genes. The water isolates were among the most desiccation susceptible strains, while strains exhibiting desiccation resistance harboured SSI-1 or both the SSI-1 and LGI1/CC8 markers. BAC resistance was greatest in planktonic LGI1/CC8 cells (relative to non-LGI1/CC8 cells), and higher BAC concentrations were also needed to inhibit the formation of biofilm by LGI1/CC8 strains during incubation for 48h and 6days compared to other strains. Formation of biofilm on stainless steel was not significantly (p>0.05) different among the strains. Analysis of genetic sequence data from desiccation and BAC sensitive (CP4 5-1, CP5 2-3, both from water), intermediate (Lm568, food) and desiccation and BAC resistant (08 5578, blood, human outbreak) strains led to the finding of amino acid differences in predicted functional protein domains in several biofilm, desiccation and peptidoglycan related genes (e.g., lmo0263, lmo0433, lmo0434, lmo0771, lmo0973, lmo1080, lmo1224, lmo1370, lmo1744, and lmo2558). Notably, the LGI1/CC8 strain 08-5578 had a frameshift mutation in lmo1370, a gene previously

  11. Isolation and characterization of an atypical Siberian sturgeon herpesvirus strain in Russia: novel North American Acipenserid herpesvirus 2 strain in Europe?

    Science.gov (United States)

    Doszpoly, A; Kalabekov, I M; Breyta, R; Shchelkunov, I S

    2017-10-01

    Siberian sturgeon herpesvirus (SbSHV) was isolated in Russia for the first time in 2006. Nine SbSHV isolates were recovered from different fish hatcheries producing the same cytopathic effect in cell cultures, the same clinical signs and mortality kinetics in virus-infected fish and the same virus neutralization pattern and shared identical nucleotide sequences. In 2011, a new isolate was recovered from juvenile sturgeon, which caused completely different cytopathic effect. That isolate was not readily neutralized by Siberian sturgeon hyperimmune antisera, and its DNA was not recognized by the routine PCR developed for SbSHV detection. Molecular study of the novel isolate revealed that it was more closely related to North American Acipenserid herpesvirus 2 (AciHV-2) isolates from white sturgeon, while the genome sequences of the former SbSHV isolates showed high similarity to the AciHV-2 isolated from shortnose sturgeon. While clinical signs and mortality caused by the novel isolate in infected Siberian sturgeon were similar to those of the formerly described SbSHV isolates, the incubation period and mean time to death produced by the novel isolate were twice as long. The differences between the former isolates and the recent one suggest that a novel SbSHV strain emerged in Europe and the molecular findings imply its North American origin. © 2017 John Wiley & Sons Ltd.

  12. Isolation and characterization of butachlor-catabolizing bacterial strain Stenotrophomonas acidaminiphila JS-1 from soil and assessment of its biodegradation potential.

    Science.gov (United States)

    Dwivedi, S; Singh, B R; Al-Khedhairy, A A; Alarifi, S; Musarrat, J

    2010-07-01

    Isolation, characterization and assessment of butachlor-degrading potential of bacterial strain JS-1 in soil. Butachlor-degrading bacteria were isolated using enrichment culture technique. The morphological, biochemical and genetic characteristics based on 16S rDNA sequence homology and phylogenetic analysis confirmed the isolate as Stenotrophomonas acidaminiphila strain JS-1. The strain JS-1 exhibited substantial growth in M9 mineral salt medium supplemented with 3.2 mmol l(-1) butachlor, as a sole source of carbon and energy. The HPLC analysis revealed almost complete disappearance of butachlor within 20 days in soil at a rate constant of 0.17 day(-1) and half-life (t((1/2))) of 4.0 days, following the first-order rate kinetics. The strain JS-1 in stationary phase of culture also produced 21.0 microg ml(-1) of growth hormone indole acetic acid (IAA) in the presence of 500 microg ml(-1) of tryptophan. The IAA production was stimulated at lower concentrations of butachlor, whereas higher concentrations above 0.8 mmol l(-1) were found inhibitory. The isolate JS-1 characterized as Stenotrophomonas acidaminiphila was capable of utilizing butachlor as sole source of carbon and energy. Besides being an efficient butachlor degrader, it substantially produces IAA. The bacterial strain JS-1 has a potential for butachlor remediation with a distinctive auxiliary attribute of plant growth stimulation.

  13. Characterisation and biochemical properties of predominant lactic acid bacteria from fermenting cassava for selection as starter cultures.

    Science.gov (United States)

    Kostinek, M; Specht, I; Edward, V A; Pinto, C; Egounlety, M; Sossa, C; Mbugua, S; Dortu, C; Thonart, P; Taljaard, L; Mengu, M; Franz, C M A P; Holzapfel, W H

    2007-03-20

    A total of 375 lactic acid bacteria were isolated from fermenting cassava in South Africa, Benin, Kenya and Germany, and were characterised by phenotypic and genotypic tests. These could be divided into five main groups comprising strains of facultatively heterofermentative rods, obligately heterofermentative rods, heterofermentative cocci, homofermentative cocci and obligately homofermentative rods, in decreasing order of predominance. Most of the facultatively heterofermentative rods were identified by phenotypic tests as presumptive Lactobacillus plantarum-group strains, which also comprised the most predominant bacteria (54.4% of strains) isolated in the study. The next predominant group of lactic acid bacteria (14.1% of total isolates) consisted of obligately heterofermentative rods belonging either to the genus Lactobacillus or Weissella, followed by the heterofermentative cocci (13.9% of isolates) belonging to the genera Weissella or Leuconostoc. Homofermentative cocci were also isolated (13.3% of isolates). Biochemical properties such as production of alpha-amylase, beta-glucosidase, tannase, antimicrobials (presumptive bacteriocin and H(2)O(2)-production), acidification and fermentation of the indigestible sugars raffinose and stachyose, were evaluated in vitro for selection of potential starter strains. A total of 32 strains with one or more desirable biochemical properties were pre-selected and identified using rep-PCR fingerprinting in combination with 16S rRNA sequencing of representative rep-PCR cluster isolates. Of these strains, 18 were identified as L. plantarum, four as Lactobacillus pentosus, two each as Leuconostoc fallax, Weissella paramesenteroides and Lactobacillus fermentum, one each as Leuconostoc mesenteroides subsp. mesenteroides and Weissella cibaria, while two remained unidentified but could be assigned to the L. plantarum-group. These strains were further investigated for clonal relationships, using RAPD-PCR with three primers, and of

  14. Isolation and sequence characterization of DNA-A genome of a new begomovirus strain associated with severe leaf curling symptoms of Jatropha curcas L.

    Science.gov (United States)

    Chauhan, Sushma; Rahman, Hifzur; Mastan, Shaik G; Pamidimarri, D V N Sudheer; Reddy, Muppala P

    2018-07-20

    Begomoviruses belong to the family Geminiviridae are associated with several disease symptoms, such as mosaic and leaf curling in Jatropha curcas. The molecular characterization of these viral strains will help in developing management strategies to control the disease. In this study, J. curcas that was infected with begomovirus and showed acute leaf curling symptoms were identified. DNA-A segment from pathogenic viral strain was isolated and sequenced. The sequenced genome was assembled and characterized in detail. The full-length DNA-A sequence was covered by primer walking. The genome sequence showed the general organization of DNA-A from begomovirus by the distribution of ORFs in both viral and anti-viral strands. The genome size ranged from 2844 bp-2852 bp. Three strains with minor nucleotide variations were identified, and a phylogenetic analysis was performed by comparing the DNA-A segments from other reported begomovirus isolates. The maximum sequence similarity was observed with Euphorbia yellow mosaic virus (FN435995). In the phylogenetic tree, no clustering was observed with previously reported begomovirus strains isolated from J. curcas host. The strains isolated in this study belong to new begomoviral strain that elicits symptoms of leaf curling in J. curcas. The results indicate that the probable origin of the strains is from Jatropha mosaic virus infecting J. gassypifolia. The strains isolated in this study are referred as Jatropha curcas leaf curl India virus (JCLCIV) based on the major symptoms exhibited by host J. curcas. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Identification and statistical optimization of fermentation conditions for a newly isolated extracellular cholesterol oxidase-producing Streptomyces cavourensis strain NEAE-42

    OpenAIRE

    El-Naggar, Noura El-Ahmady; El-Shweihy, Nancy M.; El-Ewasy, Sara M.

    2016-01-01

    Background Due to broad range of clinical and industrial applications of cholesterol oxidase, isolation and screening of bacterial strains producing extracellular form of cholesterol oxidase is of great importance. Results One hundred and thirty actinomycete isolates were screened for their cholesterol oxidase activity. Among them, a potential culture, strain NEAE-42 is displayed the highest extracellular cholesterol oxidase activity. It was selected and identified as Streptomyces cavourensis...

  16. Draft Genome Sequence of Komagataeibacter intermedius Strain AF2, a Producer of Cellulose, Isolated from Kombucha Tea.

    Science.gov (United States)

    Dos Santos, Renato Augusto Corrêa; Berretta, Andresa Aparecida; Barud, Hernane da Silva; Ribeiro, Sidney José Lima; González-García, Laura Natalia; Zucchi, Tiago Domingues; Goldman, Gustavo H; Riaño-Pachón, Diego M

    2015-12-03

    Here, we present the draft genome sequence of Komagataeibacter intermedius strain AF2, which was isolated from Kombucha tea and is capable of producing cellulose, although at lower levels compared to another bacterium from the same environment, K. rhaeticus strain AF1. Copyright © 2015 dos Santos et al.

  17. Distribution and content of class 1 integrons in different Vibrio cholerae O-serotype strains isolated in Thailand

    DEFF Research Database (Denmark)

    Dalsgaard, Anders; Forslund, Anita; Serichantalergs, Oralak

    2000-01-01

    only a single antibiotic resistance gene. Although resistance genes in class 1 integrons were found in strains from the same epidemic, as well as in unrelated non-O1, non-O139 strains isolated from children with diarrhea, they were found to encode only some of the antibiotic resistance expressed...

  18. Genome Sequence of Carbon Dioxide-Sequestering Serratia sp. Strain ISTD04 Isolated from Marble Mining Rocks

    OpenAIRE

    Kumar, Manish; Gazara, Rajesh Kumar; Verma, Sandhya; Kumar, Madan; Verma, Praveen Kumar; Thakur, Indu Shekhar

    2016-01-01

    The Serratia sp. strain ISTD04 has been identified as a carbon dioxide (CO2)-sequestering bacterium isolated from marble mining rocks in the Umra area, Rajasthan, India. This strain grows chemolithotrophically on media that contain sodium bicarbonate (NaHCO3) as the sole carbon source. Here, we report the genome sequence of 5.07?Mb Serratia sp. ISTD04.

  19. Production of anatoxin-a by cyanobacterial strains isolated from Portuguese fresh water systems.

    Science.gov (United States)

    Osswald, Joana; Rellán, Sandra; Gago-Martinez, Ana; Vasconcelos, Vítor

    2009-11-01

    The occurrence of anatoxin-a in several freshwater systems in Portugal and its production by Portuguese cyanobacterial strains, after cultivation in laboratory, were studied. Surface water samples from 9 water bodies, for recreational and human consumption usage, were surveyed for anatoxin-a presence and for obtaining cultures of pure cyanobacterial strains. Anatoxin-a analysis was performed by high performance liquid chromatography (HPLC) with fluorescence detection (FLD) followed by Mass Spectrometry (MS) confirmation. No anatoxin-a was detected in all the natural water samples (limit of detection (LOD) = 25 ng l(-1)) but among the 22 isolated cyanobacterial strains, 13 could produce anatoxin-a in laboratory conditions (LOD = 3 ng g(-1) dw). This proportion of anatoxin-a producing strains (59.1%) in laboratory is discussed considering the hypothesis that anatoxin-a is a more frequent metabolite in cyanobacteria than it was thought before and making its occurrence in Portuguese freshwaters almost certain. Therefore, health and ecological risks caused by anatoxin-a in Portugal, should be seriously considered.

  20. Isolation and characterisation of an enterocin P-producing Enterococcus lactis strain from a fresh shrimp (Penaeus vannamei).

    Science.gov (United States)

    Ben Braïek, Olfa; Ghomrassi, Hamdi; Cremonesi, Paola; Morandi, Stefano; Fleury, Yannick; Le Chevalier, Patrick; Hani, Khaled; Bel Hadj, Omrane; Ghrairi, Taoufik

    2017-06-01

    Screening for lactic acid bacteria (LAB) from fresh shrimp samples (Penaeus vannamei) collected from retail seafood markets in the Tunisian's coast, resulted in the isolation of an Enterococcus strain termed Q1. This strain was selected for its antagonistic activity against pathogenic bacteria such as Listeria monocytogenes, Pseudomonas aeruginosa, Lactococcus garvieae and against fungi (Aspergillus niger and Fusarium equiseti). The Q1 strain was characterised using standard morphological and biochemical tests, growth assays at different temperatures, pH and salinity. 16S rRNA, rpoA and pheS gene sequencing, as well as the 16S-23S rRNA intergenic spacer analyses, were combined to identify strain Q1 as a strain of Enterococcus lactis. The bacteriocin produced by E. lactis Q1 is thermostable, active in the pH range from 4.0 to 9.0 and has a bactericidal mode of action. The enterocin P structural gene was detected by specific PCR in strain E. lactis Q1, which is in good agreement with SDS-PAGE data of the purified bacteriocin. A lack of significant antibiotic resistance genes and virulence determinants was confirmed by specific PCRs. This work provides the first description of an enterocin P producer E. lactis strain isolated from a fresh shrimp. Based on its safety properties (absence of haemolytic activity, virulence factors and antibiotic resistance genes), this strain has the potential to be used as a natural additive or adjunct protective culture in food biopreservation and/or probiotic culture.

  1. Isolation of thermotolerant Vermamoeba vermiformis strains from water sources in Lanzarote Island, Canary Islands, Spain.

    Science.gov (United States)

    Reyes-Batlle, María; Wagner, Carolina; Zamora-Herrera, Jonadab; Vargas-Mesa, Alejandro; Sifaoui, Ines; González, Ana C; López-Arencibia, Atteneri; Valladares, Basilio; Martínez-Carretero, Enrique; Piñero, José E; Lorenzo-Morales, Jacob

    2016-09-01

    In this study, twenty water samples were collected in the island of Lanzarote, Canary Islands, Spain in order to check for the presence of V. vermiformis strains in these samples. Water samples were cultured on 2% Non-Nutrient Agar (NNA) plates covered with a thin layer of heat killed E. coli and checked daily for the presence of Vermamoeba. After a week, V. vermiformis amoebae were observed in 2 of the 20 processed samples (10%) incubated at room temperature and 37°C. Molecular characterization was carried out by amplifying the 18S rDNA gene and DNA sequencing in order to confirm the identity of the isolated amoebic strains. To the best of our knowledge, this is the first report on the presence of FLA in environmental sources in Lanzarote Island and the first report of Vermamoeba vermiformis in water sources in this island. Furthermore, the two strains isolated in this study were collected in recreational areas with close contact with humans and thus awareness should be raised.

  2. Validation of the Abbreviated Brucella AMOS PCR as a Rapid Screening Method for Differentiation of Brucella abortus Field Strain Isolates and the Vaccine Strains, 19 and RB51

    OpenAIRE

    Ewalt, Darla R.; Bricker, Betsy J.

    2000-01-01

    The Brucella AMOS PCR assay was previously developed to identify and differentiate specific Brucella species. In this study, an abbreviated Brucella AMOS PCR test was evaluated to determine its accuracy in differentiating Brucella abortus into three categories: field strains, vaccine strain 19 (S19), and vaccine strain RB51/parent strain 2308 (S2308). Two hundred thirty-one isolates were identified and tested by the conventional biochemical tests and Brucella AMOS PCR. This included 120 isola...

  3. In vitro screening of selected probiotic properties of Lactobacillus strains isolated from traditional fermented cabbage and cucumber.

    Science.gov (United States)

    Zielińska, Dorota; Rzepkowska, Anna; Radawska, Anna; Zieliński, Konrad

    2015-02-01

    Most important during probiotic selection are gastric acid and bile tolerance, the adhesion to the luminal epithelium to colonize the lower gastrointestinal tract of a human and safety for human consumption. The aim of this study was to evaluate the selected probiotic in vitro properties of Lactobacillus spp. Strains isolated from traditional fermented food. A total 38 strains were isolated from the pickled samples and 14 were identified as Lactobacillus spp. The survival of almost all strains after incubation at pH 2.5 did not change markedly, and remained at above 90 % (10(9) CFU/mL). The strains also exhibited a high survival rate at pH 3.5 (>90 %), whereas pH 1.5 all were died. Just four strains could survive 90 min. at pH 1.5 (survival rates of 81-94 % after 24 h, whereas after incubation in 2 and 4 % bile salt solution it was 59-94 %. All tested strains showed very good and good resistance to 0.4 % phenol addition, however only Lb. johnsonii K4 was able to multiply. The hydrophobic nature of the cell surface of the tested strains was moderated recording hydrophobicity of Lb. johnsonii K4 and Lb. rhamnosus K3 above 60 %. Safety evaluation excluded four of tested strains as candidate probiotics, according to antibiotic resistance patterns and certain metabolic activities. On the basis on the results 10 of the selected Lactobacillus strains are safe and can survive under gastrointestinal conditions, which requires them to future in vitro and in vivo probiotic studies.

  4. Development of Antibiotic Resistance Against Ureaplasma urealyticum Strains Isolated from Urogenital Samples

    Directory of Open Access Journals (Sweden)

    Musa Saraçoğlu

    2018-04-01

    Full Text Available Objective: To assess any change in the antibiotic sensitivity of Ureaplasma urealyticum strains isolated from urogenital samples in the course of time. Materials and Methods: Hospital records were retrospectively examined and cases with growth of U. urealyticum in urogenital samples in the years 2008 and 2013 were identified. Furthermore, the change in the course of time was examined by taking into consideration the cases we reported in 2001. Results: Higher rates of sensitivity against tetracycline and doxycycline were observed in 60 patients with isolated U. urealyticum. Higher rates of resistance against ofloxacin and ciprofloxacin were observed. A significant difference was found in resistance against antibiotics when the records of 2008 and 2013 were compared. A statistically significant increase was found in resistance against ofloxacin and ciprofloxacin when the records of 2001 were compared with the records of 2008 and 2013 (p<0.0005. Conclusion: U. urealyticum strains demonstrated high levels of resistance to quinolones. Resistance development is increasing in the course of time. Sensitivity against tetracycline and doxycycline has continued at high rates. It would be beneficial to consider these results during empirical treatment to be applied in cases ineligible for culturing.

  5. Isolation and identification of oedogonium species and strains for biomass applications.

    Directory of Open Access Journals (Sweden)

    Rebecca J Lawton

    Full Text Available Freshwater macroalgae from the genus Oedogonium have recently been targeted for biomass applications; however, strains of Oedogonium for domestication have not yet been identified. Therefore, the objective of this study was to compare the performance of isolates of Oedogonium collected from multiple geographic locations under varying environmental conditions. We collected and identified wild-type isolates of Oedogonium from three geographic locations in Eastern Australia, then measured the growth of these isolates under a range of temperature treatments corresponding to ambient conditions in each geographic location. Our sampling identified 11 isolates of Oedogonium that could be successfully maintained under culture conditions. It was not possible to identify most isolates to species level using DNA barcoding techniques or taxonomic keys. However, there were considerable genetic and morphological differences between isolates, strongly supporting each being an identifiable species. Specific growth rates of species were high (>26% day-1 under 7 of the 9 temperature treatments (average tested temperature range: 20.9-27.7°C. However, the variable growth rates of species under lower temperature treatments demonstrated that some were better able to tolerate lower temperatures. There was evidence for local adaptation under lower temperature treatments (winter conditions, but not under higher temperature treatments (summer conditions. The high growth rates we recorded across multiple temperature treatments for the majority of species confirm the suitability of this diverse genus for biomass applications and the domestication of Oedogonium.

  6. Determination Pattern of Antibiotic Resistance in Entropathogenic Escherichia coli Strains Isolated from Children with Diarrhea

    Directory of Open Access Journals (Sweden)

    P. Karami

    2012-04-01

    Full Text Available Introduction & Objective: Diarrheal diseases are considered a major health problem, especially in children. Enteropathogenic Escherichia coli (EPEC strains are the common cause of diarrhea in children especially in developing countries. Because of undesirable effects of diarrhea and its interference with children's growth, in some cases antibiotic treatment is recommended. In recent years, resistance toward common and effective antibiotics in the treatment of infectious diseases became one of the most important challenges in medical society, for this purpose, antibiotic sensitivity and resistance of strains in every geographical zone must be determined. So in this study, of antibiotic patterns of these bacteria were examined.Materials & Methods: This cross-sectional study was performed on 192 strains of Enteropathogen Escherichia coli isolated from children who were suffering from diarrhea in 1389-1390 in the microbiology laboratory of Hamadan University of medical sciences. To identify these strains, standard biochemical and serology tests were used. The antibiotic sensitivity test of these isolates was carried out with disc diffusion agar method according to the CLSI standards for 14 different antibiotics disc. Resistance toward 3 or more than 3 classes of antibiotics were defined as multidrug resistance.Results: The result of this study shows EPEC strains had the highest resistance to cefpodoxime (97%, trimethoprim (60.7%, tetracycline (58.4% and ampicillin (45.8%. Multidrug resistance was 68.7 percent. These strains also showed the highest sensitivity against imipenem, ceftriaxone, and ciprofloxacin antibiotics.Conclusion: EPEC strains that were studied with resistance to ampicillin, tetracycline and convenient sensitivity against fluoroquinolones are one of the major factors in children’s diarrhea. A result of this research suggests that antimicrobial resistance in Escherichia coli strains are high and prescribing and antibiotic is not

  7. Isolation, screening and molecular identification of novel bacterial strain removing methylene blue from water solutions

    Science.gov (United States)

    Kilany, Mona

    2017-11-01

    The potentially deleterious effects of methylene blue (MB) on human health drove the interest in its removal promptly. Bioremediation is an effective and eco friendly for removing MB. Soil bacteria were isolated and examined for their potential to remove MB. The most potent bacterial candidate was characterized and identified using 16S rRNA sequence technique. The evolutionary history of the isolate was conducted by maximum likelihood method. Some physiochemical parameters were optimized for maximum decolorization. Decolorization mechanism and microbial toxicity study of MB (100 mg/l) and by-products were investigated. Participation of heat killed bacteria in color adsorption have been investigated too. The bacterial isolate was identified as Stenotrophomonas maltophilia strain Kilany_MB 16S ribosomal RNA gene with 99% sequence similarity. The sequence was submitted to NCBI (Accession number = KU533726). Phylogeny depicted the phylogenetic relationships between 16S ribosomal RNA gene, partial sequence (1442 bp), of the isolated strain and other strains related to Stenotrophomonas maltophilia in the GenBank database. The optimal conditions were investigated to be pH 5 at 30 °C, after 24 h using 5 mg/l MB showing optimum decolorization percentage (61.3%). Microbial toxicity study demonstrated relative reduction in the toxicity of MB decolorized products on test bacteria. Mechanism of color removal was proved by both biosorption and biodegradation, where heat-killed and live cells showed 43 and 52% of decolorization, respectively, as a maximum value after 24-h incubation. It was demonstrated that the mechanism of color removal is by adsorption. Therefore, good performance of S maltophilia in MB color removal reinforces the exploitation of these bacteria in environmental clean-up and restoration of the ecosystem.

  8. Identification of yeast strains isolated from marcha in Sikkim, a microbial starter for amylolytic fermentation.

    Science.gov (United States)

    Tsuyoshi, Naoko; Fudou, Ryosuke; Yamanaka, Shigeru; Kozaki, Michio; Tamang, Namrata; Thapa, Saroj; Tamang, Jyoti P

    2005-03-15

    Marcha or murcha is a traditional amylolytic starter used to produce sweet-sour alcoholic drinks, commonly called jaanr in the Himalayan regions of India, Nepal, Bhutan, and Tibet (China). The aim of this study was to examine the microflora of marcha collected from Sikkim in India, focusing on yeast flora and their roles. Twenty yeast strains were isolated from six samples of marcha and identified by genetic and phenotypic methods. They were first classified into four groups (Group I, II, III, and IV) based on physiological features using an API test. Phylogenetic, morphological, and physiological characterization identified the isolates as Saccharomyces bayanus (Group I); Candida glabrata (Group II); Pichia anomala (Group III); and Saccharomycopsis fibuligera, Saccharomycopsis capsularis, and Pichia burtonii (Group IV). Among them, the Group I, II, and III strains produced ethanol. The isolates of Group IV had high amylolytic activity. Because all marcha samples tested contained both starch degraders and ethanol producers, it was hypothesized that all four groups of yeast (Group I, II, III, and IV) contribute to starch-based alcohol fermentation.

  9. Characterization of cefalexin degradation capabilities of two Pseudomonas strains isolated from activated sludge.

    Science.gov (United States)

    Lin, Bokun; Lyu, Jinling; Lyu, Xian-jin; Yu, Han-qing; Hu, Zhong; Lam, James C W; Lam, Paul K S

    2015-01-23

    Pharmaceuticals have recently been regarded as contaminants of emerging concern. To date, there is limited knowledge about antibiotic-degrading microorganisms in conventional activated sludge treatment systems and their characteristics toward antibiotic degradation especially in the presence of a pharmaceutical mixture. As such, antibiotic-degrading microorganisms were investigated and isolated from the activated sludge, and their degradation capabilities were evaluated. Two strains of cefalexin-degrading bacteria CE21 and CE22 were isolated and identified as Pseudomonas sp. in the collected activated sludge. Strain CE22 was able to degrade over 90% of cefalexin, while CE21 was able to remove 46.7% of cefalexin after incubation for 24h. The removal efficiency of cefalexin by CE22, different from that of CE21, was not significantly affected by an increase in cefalexin concentration, even up to 10ppm, however the presence of 1ppm of other pharmaceuticals had a significant effect on the degradation of cefalexin by CE22, but no significant effect on CE21. The degradation product of cefalexin by the two strains was identified to be 2-hydroxy-3-phenyl pyrazine. Our results also indicated that CE21 and CE22 were able to degrade caffeine, salicylic acid and chloramphenicol. Moreover, CE21 was found to be capable of eliminating sulfamethoxazole and naproxen. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Clinical isolates of Enterococcus faecium exhibit strain-specific collagen binding mediated by Acm, a new member of the MSCRAMM family.

    Science.gov (United States)

    Nallapareddy, Sreedhar R; Weinstock, George M; Murray, Barbara E

    2003-03-01

    A collagen-binding adhesin of Enterococcus faecium, Acm, was identified. Acm shows 62% similarity to the Staphylococcus aureus collagen adhesin Cna over the entire protein and is more similar to Cna (60% and 75% similarity with Cna A and B domains respectively) than to the Enterococcus faecalis collagen-binding adhesin, Ace, which shares homology with Acm only in the A domain. Despite the detection of acm in 32 out of 32 E. faecium isolates, only 11 of these (all clinical isolates, including four vancomycin-resistant endocarditis isolates and seven other isolates) exhibited binding to collagen type I (CI). Although acm from three CI-binding vancomycin-resistant E. faecium clinical isolates showed 100% identity, analysis of acm genes and their promoter regions from six non-CI-binding strains identified deletions or mutations that introduced stop codons and/or IS elements within the gene or the promoter region in five out of six strains, suggesting that the presence of an intact functional acm gene is necessary for binding of E. faecium strains to CI. Recombinant Acm A domain showed specific and concentration-dependent binding to collagen, and this protein competed with E. faecium binding to immobilized CI. Consistent with the adherence phenotype and sequence data, probing with Acm-specific IgGs purified from anti-recombinant Acm A polyclonal rabbit serum confirmed the surface expression of Acm in three out of three collagen-binding clinical isolates of E. faecium tested, but in none of the strains with a non-functional pseudo acm gene. Introduction of a functional acm gene into two non-CI-binding natural acm mutant strains conferred a CI-binding phenotype, further confirming that native Acm is sufficient for the binding of E. faecium to CI. These results demonstrate that acm, which encodes a potential virulence factor, is functional only in certain infection-derived clinical isolates of E. faecium, and suggest that Acm is the primary adhesin responsible for the

  11. Capsular polysaccharide typing of domestic mastitis-causing Staphylococcus aureus strains and its potential exploration of bovine mastitis vaccine development. I. Capsular polysaccharide typing, isolation and purification of the strains.

    Science.gov (United States)

    Han, H R; Pak, S I; Kang, S W; Jong, W S; Youn, C J

    2000-06-01

    One hundred seven isolates of Staphylococcus aureus from bovine mastitis were investigated for colony morphology in serum-soft agar (SSA), autoagglutination in salt, and capsular serotype. Capsular polysaccharide (CP) was purified and quantified from the extracts of clinical isolates. Overall, 89 isolates (83.2%) were diffuse in the SSA, without any difference in the proportion of diffuse colony between type 5 and type 8 strains. Some strains exhibited compact colonies in the SSA and expressed CP as determined by an enzyme-linked immunosorbent assay, indicating that compact morphology does not exclude encapsulation. The majority of the strains (11/12) showed autoagglutination in the salt aggregation test. The serotype 336 accounted for 46.7% of the isolates followed by serotype 5 (12.1%) and serotype 8 (12.1%). Particularly, twenty-six (24.3%) isolates reacted with two serotypes; 7 for type 8/336 and 19 for type 5/336. Five isolates (4.7%) were nontypeable with monoclonal antibodies specific for CP serotype 5, 8, or 336. The CP concentration in culture supernatants varied with the serotypes, and the total amount of CP produced by cells grown in a liquid medium was much less than that produced by cells grown on a solid medium. The Western blotting indicated that the CP bands of S. aureus serotype 5 and 8 were ranged in the molecular mass of 58-84 kilodalton (kDa), with additional bands in the region of approximately >/= 48 or

  12. Typing clinical and animal environment Aspergillus fumigatus gliotoxin producer strains isolated from Brazil by PCR-RFLP markers.

    Science.gov (United States)

    Soleiro, C A; Pena, G A; Cavaglieri, L R; Coelho, I; Keller, L M; Dalcero, A M; Rosa, C A R

    2013-12-01

    Aspergillus fumigatus, a well-known human and animal pathogen causing aspergillosis, has been historically identified by morphological and microscopic features. However, recent studies have shown that species identification on the basis of morphology alone is problematic. The aim of this work was to confirm the taxonomic state at specie level of a set of clinical (human and animal) and animal environment A. fumigatus strains identified by morphological criteria applying a PCR-RFLP assay by an in silico and in situ analysis with three restriction enzymes. The A. fumigatus gliotoxin-producing ability was also determined. Previous to the in situ PCR-RFLP analysis, an in silico assay with BccI, MspI and Sau3AI restriction enzymes was carried out. After that, these enzymes were used for in situ assay. All A. fumigatus strains isolated from corn silage, human aspergillosis and bovine mastitis and high per cent of the strains isolated from cereals, animal feedstuff and sorghum silage were able to produce high gliotoxin levels. Also, all these strains identified by morphological criteria as A. fumigatus, regardless of its isolation source, had band patterns according to A. fumigatus sensu stricto by PCR-RFLP markers. Aspergillus fumigatus is a well-known human and animal pathogen causing aspergillosis. In this study, clinical (human and animal) and animal environment strains were able to produce high gliotoxin levels and had band profiles according to A. fumigatus sensu stricto by PCR-RFLP markers. The results obtained here suggest that strains involved in human and animal aspergillosis could come from the animal environment in which A. fumigatus is frequently found. Its presence in animal environments could affect animal health and productivity; in addition, there are risks of contamination for rural workers during handling and storage of animal feedstuffs. © 2013 The Society for Applied Microbiology.

  13. Genetic diversity and virulence genes in Streptococcus uberis strains isolated from bovine mastitis

    Directory of Open Access Journals (Sweden)

    Rafael Ambrósio Loures

    2017-08-01

    Full Text Available Mastitis is one of the most common and costly infectious diseases in dairy cattle worldwide. This is a multifactorial illness caused by different microorganisms, including virus, yeasts, algae, parasites, and several species of bacteria. Among these bacteria, Streptococcus uberis is an important environmental pathogen that is responsible for a large range of clinical and subclinical mammary infections, especially in intensively managed herds. Despite the increasing importance of this pathogen in the etiology of bovine mastitis, data on its virulence and diversity in Brazilian dairy herds are scarce. The aims of the present study were to investigate the virulence characteristics of S. uberis isolated from bovine mastitis and to assess the molecular epidemiology of the Brazilian isolates using pulsed-field gel electrophoresis (PFGE. In this work, 46 strains of S. uberis isolated from bovine mastitis from 26 Brazilian dairy herds were evaluated regarding their genetic diversity by PFGE using with the SmaI enzyme. Additionally, the presence of the virulence genes skc and pauA, which encode plasminogen activators, and the gene sua, which encodes an adhesion molecule in mammary epithelial cells, were assessed by PCR. Our results showed a high genetic diversity in the population, displaying many different patterns in the PFGE analysis. A high proportion of strains was positive for virulence genes in the sampled population (sua [100%], pauA [91%], and skc [91%]. The high frequency of skc, pauA, and sua genes among the studied strains suggests the importance of these virulence factors, possibly helping S. uberis in the colonization of the bovine mammary gland. Surveys of the genetic and molecular characteristics of this pathogen can improve our knowledge of bacterial activity and identify molecules that have roles in the establishment of the infection. This might help in the development of more effective measures to control and prevent bovine mastitis.

  14. Cellulase and xylanase productions by isolated Amazon Bacillus strains using soybean industrial residue based solid-state cultivation

    Directory of Open Access Journals (Sweden)

    Heck Júlio X.

    2002-01-01

    Full Text Available In Brazil, a large amount of a fibrous residue is generated as result of soybean (Glycine max protein production. This material, which is rich in hemicellulose and cellulose, can be used in solid state cultivations for the production of valuable metabolites and enzymes. In this work, we studied the bioconversion of this residue by bacteria strains isolated from water and soil collected in the Amazon region. Five strains among 87 isolated bacteria selected for their ability to produce either celullases or xylanases were cultivated on the aforementioned residue. From strain BL62, identified as Bacillus subtilis, it was obtained a preparation showing the highest specific cellulase activity, 1.08 UI/mg protein within 24 hours of growth. Concerning xylanase, the isolate BL53, also identified as Bacillus subtilis, showed the highest specific activity for this enzyme, 5.19 UI/mg protein within 72 hours of cultivation. It has also been observed the production of proteases that were associated with the loss of cellulase and xylanase activities. These results indicated that the selected microorganisms, and the cultivation process, have great biotechnological potential.

  15. Synergistic effect of eugenol with Colistin against clinical isolated Colistin-resistant Escherichia coli strains

    Directory of Open Access Journals (Sweden)

    Yi-ming Wang

    2018-01-01

    Full Text Available Abstract Background Bacterial infections have become more challenging to treat due to the emergence of multidrug-resistant pathogenic bacteria. Combined antibiotics prove to be a relatively effective method to control such resistant strains. This study aim to investigate synergistic activity of eugenol combined with colistin against a collection of clinical isolated Escherichia coli (E.coli strains, and to evaluate potential interaction. Methods Antimicrobial susceptibility, minimum inhibitory concentration (MIC and fractional inhibitory concentration index (FICI of the bacteria were determined by disk diffusion assay, broth microdilution method and checkerboard assay, respectively. The mcr-1 mRNA expression was measured by Real-time PCR. To predict possible interactions between eugenol and MCR-1, molecular docking assay was taken. Results For total fourteen strains including eight colistin-resistant strains, eugenol was determined with MIC values of 4 to 8 μg/mL. Checkerboard dilution test suggested that eugenol exhibited synergistic activity when combined with colistin (FICI ranging from 0.375 to 0.625. Comparison analysis of Real-time PCR showed that synergy could significantly down-regulate expression of mcr-1 gene. A metal ion coordination bond with catalytic zinc atom and a hydrogen bond with crucial amino acid residue Ser284 of MCR-1 were observed after molecular docking, indicating antibacterial activity and direct molecular interactions of eugenol with MCR-1 protein. Conclusions Our results demonstrated that eugenol exhibited synergistic effect with colistin and enhanced its antimicrobial activity. This might further contribute to the antibacterial actions against colistin-resistant E.coli strains. Graphical abstract Synergistic effect of eugenol with colistin against colistin-resistant Escherichia coli isolates.

  16. Genome Sequence of Carbon Dioxide-Sequestering Serratia sp. Strain ISTD04 Isolated from Marble Mining Rocks.

    Science.gov (United States)

    Kumar, Manish; Gazara, Rajesh Kumar; Verma, Sandhya; Kumar, Madan; Verma, Praveen Kumar; Thakur, Indu Shekhar

    2016-10-20

    The Serratia sp. strain ISTD04 has been identified as a carbon dioxide (CO 2 )-sequestering bacterium isolated from marble mining rocks in the Umra area, Rajasthan, India. This strain grows chemolithotrophically on media that contain sodium bicarbonate (NaHCO 3 ) as the sole carbon source. Here, we report the genome sequence of 5.07 Mb Serratia sp. ISTD04. Copyright © 2016 Kumar et al.

  17. Biodiversity among Lactobacillus helveticus Strains Isolated from Different Natural Whey Starter Cultures as Revealed by Classification Trees

    Science.gov (United States)

    Gatti, Monica; Trivisano, Carlo; Fabrizi, Enrico; Neviani, Erasmo; Gardini, Fausto

    2004-01-01

    Lactobacillus helveticus is a homofermentative thermophilic lactic acid bacterium used extensively for manufacturing Swiss type and aged Italian cheese. In this study, the phenotypic and genotypic diversity of strains isolated from different natural dairy starter cultures used for Grana Padano, Parmigiano Reggiano, and Provolone cheeses was investigated by a classification tree technique. A data set was used that consists of 119 L. helveticus strains, each of which was studied for its physiological characters, as well as surface protein profiles and hybridization with a species-specific DNA probe. The methodology employed in this work allowed the strains to be grouped into terminal nodes without difficult and subjective interpretation. In particular, good discrimination was obtained between L. helveticus strains isolated, respectively, from Grana Padano and from Provolone natural whey starter cultures. The method used in this work allowed identification of the main characteristics that permit discrimination of biotypes. In order to understand what kind of genes could code for phenotypes of technological relevance, evidence that specific DNA sequences are present only in particular biotypes may be of great interest. PMID:14711641

  18. Complete Genome Sequences of Zika Virus Strains Isolated from the Blood of Patients in Thailand (2014) and Philippines (2012)

    Science.gov (United States)

    2016-03-09

    Complete genome sequences of Zika Virus strains isolated from the blood of patients in 1 Thailand (2014) and Philippines (2012). 2 Ellison,D.W.1...Institute, Seoul, Republic of Korea. 20 21 Running Head: Zika Virus Genomes 22 23 ABSTRACT 24 ZIKV is an arbovirus and member of the family...genome sequences of two Zika Virus (ZIKV) strains, Zika virus /H.sapiens-27 tc/THA/2014/SV0127-14 and Zika virus /H.sapiens-tc/PHL/2012/CPC-0740, isolated

  19. Identification of bacterial strains isolated from the Mediterranean Sea exhibiting different abilities of biofilm formation.

    Science.gov (United States)

    Brian-Jaisson, Florence; Ortalo-Magné, Annick; Guentas-Dombrowsky, Linda; Armougom, Fabrice; Blache, Yves; Molmeret, Maëlle

    2014-07-01

    The Mediterranean Sea has rarely been investigated for the characterization of marine bacteria as compared to other marine environments such as the Atlantic or Pacific Ocean. Bacteria recovered from inert surfaces are poorly studied in these environments, when it has been shown that the community structure of attached bacteria can be dissimilar from that of planktonic bacteria present in the water column. The objectives of this study were to identify and characterize marine bacteria isolated from biofilms developed on inert surfaces immersed in the Mediterranean Sea and to evaluate their capacity to form a biofilm in vitro. Here, 13 marine bacterial strains have been isolated from different supports immersed in seawater in the Bay of Toulon (France). Phylogenetic analysis and different biological and physico-chemical properties have been investigated. Among the 13 strains recovered, 8 different genera and 12 different species were identified including 2 isolates of a novel bacterial species that we named Persicivirga mediterranea and whose genus had never been isolated from the Mediterranean Sea. Shewanella sp. and Pseudoalteromonas sp. were the most preponderant genera recovered in our conditions. The phenotypical characterization revealed that one isolate belonging to the Polaribacter genus differed from all the other ones by its hydrophobic properties and poor ability to form biofilms in vitro. Identifying and characterizing species isolated from seawater including from Mediterranean ecosystems could be helpful for example, to understand some aspects of bacterial biodiversity and to further study the mechanisms of biofilm (and biofouling) development in conditions approaching those of the marine environment.

  20. Evaluation of Drug Resistance Pattern of Escherichia coli Strains Isolated from Fasa Vali-e-Asr Hospital Patients

    Directory of Open Access Journals (Sweden)

    Sara Abdollahi Kheirabadi

    2013-03-01

    Full Text Available Background & Objective: Antibiotic resistance due to the widespread use of antibiotics is one of the major causes of failure in antibiotic treatment. The aim of this study was to investigate the rates of antibiotic resistance among Escherichia coli isolates from Fasa Vali-e-Asr Hospital patients.   Materials & Methods : In total, 234 isolates of Escherichia coli strains, obtained from inpatients and outpatients, were studied. The identity of the isolated strains was confirmed by bacteriologic methods. T he drug sensitivity definition test to 17 antibiotics was done via the disk diffusion antibiogram method. Minimum inhibitory concentration (MIC of the resistant isolates to Ciprofloxacin and Imipenem was measured using the s erial dilution method according to the CLSI standards.   Results : The resistance rates of the isolates to Ciprofloxacin and Imipenem by disk diffusion antibiogram method were 22.65% and 11.11% and by serial dilution method were 19.66 % and 9.4% of all the isolates, respectively.   Conclusion: These results show higher resistance of Escherichia coli to Ciprofloxacin and Imipenem as compared to the results in previous studies. Further investigation will shed light on how to more effectively battle antibiotic resistance of virulent microorganisms.

  1. Phylogenetic analysis of Tomato spotted wilt virus (TSWV) NSs protein demonstrates the isolated emergence of resistance-breaking strains in pepper.

    Science.gov (United States)

    Almási, Asztéria; Csilléry, Gábor; Csömör, Zsófia; Nemes, Katalin; Palkovics, László; Salánki, Katalin; Tóbiás, István

    2015-02-01

    Resurgence of Tomato spotted wilt virus (TSWV) worldwide as well as in Hungary causing heavy economic losses directed the attention to the factors contributing to the outbreak of this serious epidemics. The introgression of Tsw resistance gene into various pepper cultivars seemed to solve TSWV control, but widely used resistant pepper cultivars bearing the same, unique resistance locus evoked the rapid emergence of resistance-breaking (RB) TSWV strains. In Hungary, the sporadic appearance of RB strains in pepper-producing region was first observed in 2010-2011, but in 2012 it was detected frequently. Previously, the non-structural protein (NSs) encoded by small RNA (S RNA) of TSWV was verified as the avirulence factor for Tsw resistance, therefore we analyzed the S RNA of the Hungarian RB and wild type (WT) isolates and compared to previously analyzed TSWV strains with RB properties from different geographical origins. Phylogenetic analysis demonstrated that the different RB strains had the closest relationship with the local WT isolates and there is no conserved mutation present in all the NSs genes of RB isolates from different geographical origins. According to these results, we concluded that the RB isolates evolved separately in geographic point of view, and also according to the RB mechanism.

  2. Occurrence Of Virulence Factors And Antimicrobial Resistance In Pasteurella Multocida Strains Isolated From Slaughter Cattle In Iran

    Directory of Open Access Journals (Sweden)

    Faham eKhamesipour

    2014-10-01

    Full Text Available A total of 30 Pasteurella multocida strains isolated from 333 pneumonic and apparently health slaughter cattle were examined for capsule biosynthesis genes and 23 virulence associated genes by polymerase chain reaction. The disc diffusion technique was used to determine antimicrobial resistance profiles among the isolates. Of the isolates, 23 belonged to capsular type A, 5 to capsular type D and two isolates were untypeable. The distribution of the capsular types in pneumonic lungs and in apparently health lungs was statistically similar. All virulence genes tested were detected among the isolates derived from pneumonic lungs; whereas isolates derived from apparently health lungs carried 16 of the 23 genes. The frequently detected genes among isolates from pneumonic lungs were exbD, hgbA, hgbB, ompA, ompH, oma87 and sodC; whereas tadD, toxA and pmHAS genes occurred less frequently. Most of the adhesins and superoxide dismutases; and all of the iron acquisition and protectin proteins occurred at significantly (p≤0.05 higher frequencies in isolates from pneumonic lungs. Isolates from apparently healthy lungs didn’t carry the following genes; hsf-1, hsf-2, tadD, toxA, nanB, nanH and pmHAS. One adhesion (hsf-1 and two iron acquisition (exbD and tonB genes occurred at significantly (p≤0.05 higher frequencies among capA isolates. All the P. multocida isolates were susceptible to ciprofloxacin, co-trimoxazole, doxycycline, enrofloxacin, nitrofurantoin and tetracyclines. Different proportions of the isolates were however resistant to ampicillin, amoxicillin, erythromycin, lincomycin, penicillin, rifampin, streptomycin and florfenicol. Our results reveal presence of virulence factors in P. multocida strains isolated from symptomatic and asymptomatic bovids. A higher frequency of the factors among isolates from symptomatic study animals may suggest their role in pathogenesis of P. multocida-associated bovine respiratory disease. The results further

  3. Technological and safety properties of newly isolated GABA-producing Lactobacillus futsaii strains.

    Science.gov (United States)

    Sanchart, C; Rattanaporn, O; Haltrich, D; Phukpattaranont, P; Maneerat, S

    2016-09-01

    To evaluate the technological and safety properties of Lactobacillus futsaii CS3 and CS5 isolated from Thai fermented shrimp products (Kung-Som) in order to develop a valuable gamma-aminobutyric acid (GABA)-producing starter culture. Both strains showed a high GABA-producing ability (>8 mg ml(-1) ) in MRS broth containing 20 mg ml(-1) monosodium glutamate (MSG) for 120 h. They also exhibited inhibitory activity against foodborne pathogens and spoilage bacteria. Cell surface hydrophobicity and proteolytic activity were observed in both strains. Strain CS3 survived better under simulated gastrointestinal tract conditions with only 1·5 log-units cell decrease over 8 h. Both strains showed the ability to deconjugate taurocholate and taurodeoxycholate acid. Neither virulence genes nor biogenic amine production was detected. Strain CS3 exhibited susceptibility to all tested antibiotics with the exception of vancomycin, while strain CS5 showed resistance to vancomycin, ampicillin and chloramphenicol. Based on the results obtained, Lact. futsaii CS3 is very promising as a GABA-producing and potentially probiotic starter culture strain for applications in functional fermented foods. This study focuses on the technological and safety characteristics of Lact. futsaii CS3 and CS5 including their high GABA-producing capacity for the first time. This provides a way of replacing chemical GABA by natural GABA using a GABA-producing starter culture candidate, at the same time offering the consumer new attractive food products. © 2016 The Society for Applied Microbiology.

  4. Potential probiotic characterization of Lactobacillus plantarum strains isolated from Inner Mongolia "Hurood" cheese.

    Science.gov (United States)

    Zhang, Jian; Zhang, Xue; Zhang, Li; Zhao, Yujuan; Niu, Chunhua; Yang, Zhennai; Li, Shengyu

    2014-02-28

    Total 121 lactic acid bacteria were isolated from homemade Inner Mongolia extra hard Hurood cheese. Seven of these strains, identified as Lactobacillus plantarum, were studied for probiotic characteristics. All seven strains survived at pH 3.0 for 3 h, or in the presence of oxgall at 0.3% or 0.6% for 4 h, but their viabilities were affected to different extents at pH 2.0 for 3 h. Strains C37 and C51 showed better adherence to Caco-2 cells, and higher hydrophobicity. The seven L. plantarum strains were different in in vitro free radical scavenging activities and cholesterolreducing ability. In vivo evaluation of the influence of L. plantarum C37 on the intestinal flora in a mouse model showed strain C37 could increase the viable counts of lactobacilli in feces of mice and decrease the viable counts of enterococci. When L. plantarum C37 was used to prepare probiotic Hurood cheese, it was able to maintain high viable counts (>7.8 log CFU/g) during the whole storage period, but the composition of the cheese was not changed. These results indicate that L. plantarum C37 could be considered as a promising probiotic strain.

  5. Closed Genome Sequence of Phytopathogen Biocontrol Agent Bacillus velezensis Strain AGVL-005, Isolated from Soybean.

    Science.gov (United States)

    Pylro, Victor Satler; Dias, Armando Cavalcante Franco; Andreote, Fernando Dini; Morais, Daniel Kumazawa; Varani, Alessandro de Mello; Andreote, Cristiane Cipolla Fasanella; Bernardo, Eduardo Roberto de Almeida; Zucchi, Tiago

    2018-02-15

    We report here the closed and near-complete genome sequence and annotation of Bacillus velezensis strain AGVL-005, a bacterium isolated from soybean seeds in Brazil and used for phytopathogen biocontrol. Copyright © 2018 Pylro et al.

  6. The isolation and preliminary characterization of native cyanobacterial and microalgal strains from lagoons contaminated with petroleum oil in Khark Island

    Directory of Open Access Journals (Sweden)

    Mostafa Noroozi

    2017-01-01

    Full Text Available Introduction: Algae has many applications in terms of ecology, biodiversity, agriculture, medicine, biotechnology, industry, etc. They are potent organisms in bio-active compound production, bioremediation and primary producer. Therefore, it is important to discover local strains with biotechnological and ecological applications. Materials and methods: Soil and water samples were collected from different sites of Khark Island (Persian Gulf. The samples were cultivated and purified using different techniques. Seven different antibiotics together with other physical methods used to purify the isolates. Results: Throughout the project 7 strains including 2 eukaryotic algae and 5 cyanobacteria have been isolated. Imipenem and cycloheximide were the best antibiotics for purification of cultures. Three of isolates were morphologically similar to Arthronema africanum, Pseudanabaena teremula, Anabaenopsis sp. However, they have some different characteristics which according to the present identification keys it is not possible to identify their identity (they have nominated Kh.C.d2, Kh.T.1 and Kh.T.2. Discussion and conclusion: According to the results, isolated strains were identified at the genus level based on morphology characters; therefore the complementary examinations such as molecular identification, ITS, 18s rRNA, 16s rRNA and sequencing can help to approve the strains identity. Upon approval of the new strains account for morphological traits are necessary for their easy identification. The Imipenem antibiotic is the best for eukaryotic algae purification and Cycloheximide is suitable for prokaryotic algae (cyanobacteria purification.

  7. Genome Sequences of Shewanella baltica and Shewanella morhuae Strains Isolated from the Gastrointestinal Tract of Freshwater Fish.

    Science.gov (United States)

    Castillo, Daniel; Gram, Lone; Dailey, Frank E

    2018-06-21

    We present here the genome sequences of Shewanella baltica strain CW2 and Shewanella morhuae strain CW7, isolated from the gastrointestinal tract of Salvelinus namaycush (lean lake trout) and Coregonus clupeaformis (whitefish), respectively. These genome sequences provide insights into the niche adaptation of these specific species in freshwater systems. Copyright © 2018 Castillo et al.

  8. Characterization of two recent Japanese field isolates of canine distemper virus and examination of the avirulent strain utility as an attenuated vaccine.

    Science.gov (United States)

    Takenaka, Akiko; Yoneda, Misako; Seki, Takahiro; Uema, Masashi; Kooriyama, Takanori; Nishi, Toshiya; Fujita, Kentaro; Miura, Ryuichi; Tsukiyama-Kohara, Kyoko; Sato, Hiroki; Kai, Chieko

    2014-12-05

    Recently, several new strains of canine distemper virus (CDV) have been isolated in Japan. To investigate their pathogenesis in dogs, the Yanaka and Bunkyo-K strains were investigated by infecting dogs and determining clinical signs, amount of virus, and antibody responses. The Yanaka strain is avirulent and induced an antibody response. The Bunkyo-K strain induced typical CDV clinical signs in infected dogs and virulence was enhanced by brain passage. Molecular and phylogenetic analyses of H genes demonstrated the Bunkyo-K strains were of a different lineage from Asia-1 group including the Yanaka strain and Asia-2 group that contain recent Japanese isolates, which were recently identified as major prevalent strains worldwide but distinct from old vaccine strains. Based on these data, we tested the ability of the Yanaka strain for vaccination. Inoculation with the Yanaka strain efficiently induced CDV neutralizing antibodies with no clinical signs, and the protection effects against challenge with either old virulent strain or Bunkyo-K strain were equal or greater when compared with vaccination by an original vaccine strain. Thus, the Yanaka strain is a potential vaccine candidate against recent prevalent CDV strains. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Biosorption of Cd, Cr, Mn, and Pb from aqueous solutions by Bacillus sp strains isolated from industrial waste activate sludge

    OpenAIRE

    García, Rocío; Campos, Juan; Cruz, Julio Alfonso; Calderón, Ma. Elena; Raynal, Ma. Elena; Buitrón, Germán

    2016-01-01

    Abstract The microorganisms are capable of accumulating heavy metal ions from water as biosorbent agents, offering a potential alternative for the detoxification and recovery of toxic/precious metals in industrial wastewater. In the present work, metal-resistant bacterial strains were isolated and identified from activated sludge of a waste treatment plant in the Municipality of Santa Rosa Jauregui, Querétaro. To obtain bacteria tolerant to metals, 37 bacterial strains and two isolates were s...

  10. [Vitamin B12-independent strains of Methylophaga marina isolated from Red Sea algae].

    Science.gov (United States)

    Li, Ts D; Doronina, N V; Ivanova, E G; Trotsenko, Iu A

    2007-01-01

    Two strains (KM3 and KM5) of halophilic methylobacteria isolated from Red Sea algae do not require vitamin B12 for growth and can use methanol, methylamine, dimethylamine, trimethylamine, dimethyl sulfide, and fructose as sources of carbon and energy. The cells of these strains are gram-negative motile monotrichous (strain KM3) or peritrichous (strain KM5) rods. The strains are strictly aerobic and require Na+ ions but not growth factors for growth. They are oxidase- and catalase-positive and reduce nitrates to nitrites. Both strains can grow in a temperature range of 4 to 37 degrees C (with optimal growth at 29-34 degrees C), at pH between 5.5 and 8.5 (with optimal growth at pH 7.5-8.0), and in a range of salt concentrations between 0.5 and 15% NaCl (with optimal growth at 5-9% NaCl). The phospholipids of these strains are dominated by phosphatidylethanolamine and phosphatidylglycerol and also include phosphatidylcholine, phosphatidylserine, and cardiolipin. The dominant fatty acids are C(16:1omega7c) and C(16:0). The major ubiquinone is Q8. The cells accumulate ectoin, glutamate, and sucrose as intracellular osmoprotectants. The strains implement the 2-keto-3-deoxy-6-phosphogluconate-dependent variant of the ribulose monophosphate pathway. The G+C content of the DNA is 44.4-44.7 mol %. Analysis of the 16S rRNA genes showed that both strains belong to Gammaproteobacteria and have a high degree of homology (99.4%) to Methylophaga marina ATCC 35842T . Based on the data of polyphasic taxonomy, strains KM3 and KM5 are identified as new strains M. marina KM3 (VKM B-2386) and M. marina KM5 (VKM B-2387). The ability of these strains to produce auxins (indole-3-acetic acid) suggests their metabolic association with marine algae.

  11. An investigation of vancomycin minimum inhibitory concentration creep among methicillin-resistant Staphylococcus aureus strains isolated from pediatric patients and healthy children in Northern Taiwan

    Directory of Open Access Journals (Sweden)

    Chia-Ning Chang

    2017-06-01

    Conclusion: Vancomycin MIC creeps existed in both clinical MRSA isolates and colonized MRSA strains. Great diversity of PFGE typing was in both strains collected. There was no association between the clinical and colonized MRSA isolates with vancomycin MIC creep.

  12. Draft genome sequence of Streptococcus equi subsp. zooepidemicus strain S31A1, isolated from equine infectious endometritis

    DEFF Research Database (Denmark)

    da Piedade, Isabelle; Skive, Bolette; Christensen, Henrik

    2013-01-01

    We present the draft genome sequence of Streptococcus equi subsp. zooepidemicus S31A1, a strain isolated from equine infectious endometritis in Denmark. Comparative analyses of this genome were done with four published reference genomes: S. zooepidemicus strains MGCS10565, ATCC 35246, and H70 and S...

  13. Study of strains of Candida spp. Isolated from catheters in UHC of Oran (Algeria): Identification and antifungal susceptibility.

    Science.gov (United States)

    Bendjelloul, M; Boucherit-Otmani, Z; Boucherit, K

    2016-09-01

    The increasing incidence of Candida spp., and the vital prognosis often compromise for patients with Candida species make urgent the exact knowledge of their distribution worldwide and exhaust action antifungals currently used in clinical. That why we carry out an epidemiological study of Candida species and testing their susceptibility against two antifungals: amphotericin B and caspofungin. Samplings of peripheral venous catheters (PVC) were carried out from during 8months on the services of Internal medicine, Surgery A and Neonatology of Oran's University Hospital Center (UHC). The study of the susceptibility of Candida species to antifungal agents was performed according to the Clinical Laboratory Standards Institute (CLSI 2008). From 300 samples, 25 yeasts were isolated. The rate of colonization PVC was 8.33% by Candida spp. The most isolated strains were Candida parapsilosis with 64% of cases, followed by Candida albicans (12%) then 8% for Candida glabrata and Candida krusei. However, only 4% of isolates were Candida famata or Candida lusitaniae. Furthermore all isolated strains were susceptible to amphotericin B with Minimum Inhibitory Concentrations (MIC) ranging from 0.25 to 1μg/mL. MIC obtained with caspofungin vary from 0.0625 to 2μg/mL for all strains. Moreover, one strain of C. krusei is resistant to caspofungin with a MIC superior to 8μg/mL. All though caspofungin is at least as effective as amphotericin B, it is better tolerated for the treatment of invasive fungal infections. Copyright © 2016. Published by Elsevier Masson SAS.

  14. Molecular Strain Typing of Clinical Isolates, Trichophyton rubrum using Non Transcribed Spacer (NTS) Region as a Molecular Marker.

    Science.gov (United States)

    Ramaraj, Vijayakumar; Vijayaraman, Rajyoganandh S; Elavarashi, Elangovan; Rangarajan, Sudha; Kindo, Anupma Jyoti

    2017-05-01

    Dermatophytes are a group of fungi which infect keratinized tissues and causes superficial mycoses in humans and animals. The group comprises of three major genera, Trichophyton , Microsporum and Epidermophyton . Among them Trichophyton rubrum is a predominant anthropophilic fungi which causes chronic infections. Although, the infection is superficial and treatable, reinfection/coinfection causes inflation in the treatment cost. Identifying the source and mode of transmission is essential to prevent its transmission. Accurate discrimination is required to understand the clinical (relapse or reinfection) and epidemiological implications of the genetic heterogeneity of this species. Polymorphism in the Non Transcribed Spacer (NTS) region of ribosomal DNA (rDNA) clusters renders an effective way to discriminate strains among T. rubrum . To carry out the strain typing of the clinical isolates, Trichophyton rubrum using NTS as a molecular marker. Seventy T.rubrum clinical isolates obtained from April-2011-March 2013, from Sri Ramachandra Medical Centre, Chennai, Tamil Nadu, India, were identified by conventional phenotypic methods and included in this prospective study. The isolates were then subjected to Polymerase Chain Reaction (PCR) targeting two subrepeat elements (SREs), TRS-1 and TRS-2 of the NTS region. Strain-specific polymorphism was observed in both subrepeat loci. Total, nine different strains were obtained on combining both TRS-1 and TRS-2, SREs. The outcome has given a strong representation for using NTS region amplification in discriminating the T. rubrum clinical isolates. The method can be adapted as a tool for conducting epidemiology and population based study in T. rubrum infections. This will help in future exploration of the epidemiology of T. rubrum .

  15. A cross strain Plasmodium falciparum microarray optimized for the transcriptome analysis of Plasmodium falciparum patient derived isolates

    KAUST Repository

    Subudhi, Amit

    2016-07-20

    Malarial parasite P. falciparum, an apicomplexan protozoan has a 23.3 MB nuclear genome and encodes ~ 5600 transcripts. The genetic diversity of the parasite within and across geographical zones is a challenge to gene expression studies which are essential for understanding of disease process, outcome and developing markers for diagnostics and prognostics. Here, we describe the strategy involved in designing a custom P. falciparum 15K array using the Agilent platform and Genotypic\\'s Right Design methodology to study the transcriptome of Indian field isolates for which genome sequence information is limited. The array contains probes representing genome sequences of two distinct geographical isolates (i.e. 3D7 and HB3) and sub-telomeric var gene sequences of a third isolate (IT4) known to adhere in culture condition. Probes in the array have been selected based on their efficiency to detect transcripts through a 244K array experimentation. Array performance for the 15K array, was evaluated and validated using RNA materials from P. falciparum clinical isolates. A large percentage (91%) of the represented transcripts was detected from Indian P. falciparum patient isolates. Replicated probes and multiple probes representing the same gene showed perfect correlation between them suggesting good probe performance. Additional transcripts could be detected due to inclusion of unique probes representing HB3 strain transcripts. Variant surface antigen (VSA) transcripts were detected by optimized probes representing the VSA genes of three geographically distinct strains. The 15K cross strain P. falciparum array has shown good efficiency in detecting transcripts from P. falciparum parasite samples isolated from patients. The low parasite loads and presence of host RNA makes arrays a preferred platform for gene expression studies over RNA-Seq.

  16. A cross strain Plasmodium falciparum microarray optimized for the transcriptome analysis of Plasmodium falciparum patient derived isolates

    KAUST Repository

    Subudhi, Amit; Boopathi, P.A.; Middha, Sheetal; Acharya, Jyoti; Rao, Sudha Narayana; Mugasimangalam, Raja C.; Sirohi, Paramendra; Kochar, Sanjay K.; Kochar, Dhanpat K.; Das, Ashis

    2016-01-01

    Malarial parasite P. falciparum, an apicomplexan protozoan has a 23.3 MB nuclear genome and encodes ~ 5600 transcripts. The genetic diversity of the parasite within and across geographical zones is a challenge to gene expression studies which are essential for understanding of disease process, outcome and developing markers for diagnostics and prognostics. Here, we describe the strategy involved in designing a custom P. falciparum 15K array using the Agilent platform and Genotypic's Right Design methodology to study the transcriptome of Indian field isolates for which genome sequence information is limited. The array contains probes representing genome sequences of two distinct geographical isolates (i.e. 3D7 and HB3) and sub-telomeric var gene sequences of a third isolate (IT4) known to adhere in culture condition. Probes in the array have been selected based on their efficiency to detect transcripts through a 244K array experimentation. Array performance for the 15K array, was evaluated and validated using RNA materials from P. falciparum clinical isolates. A large percentage (91%) of the represented transcripts was detected from Indian P. falciparum patient isolates. Replicated probes and multiple probes representing the same gene showed perfect correlation between them suggesting good probe performance. Additional transcripts could be detected due to inclusion of unique probes representing HB3 strain transcripts. Variant surface antigen (VSA) transcripts were detected by optimized probes representing the VSA genes of three geographically distinct strains. The 15K cross strain P. falciparum array has shown good efficiency in detecting transcripts from P. falciparum parasite samples isolated from patients. The low parasite loads and presence of host RNA makes arrays a preferred platform for gene expression studies over RNA-Seq.

  17. Drug Resistance and Population Structure of Mycobacterium tuberculosis Beijing Strains Isolated in Poland.

    Science.gov (United States)

    Kozińska, Monika; Augustynowicz-Kopeć, Ewa

    2015-01-01

    In total, 1095 Mycobacterium tuberculosis clinical isolates from 282 patients with drug-resistant and 813 with drug-sensitive tuberculosis (TB) in Poland during 2007-2011 were analysed. Seventy-one (6.5%) patients were found to have strains of Beijing genotype as defined by spoligotyping. The majority of patients were Polish-born; among foreign-born a large proportion came from Chechnya and Vietnam. Analysis showed strong associations between Beijing genotype infection and MDR, pre-XDR and XDR resistance, with a considerable relative risk among new patients, suggesting that this is due to increased spread of drug-resistant strains rather than acquisition of resistance during treatment.

  18. Screening of medicinal plants for antibacterial activities on Staphylococcus aureus strains isolated from bovine mastitis

    Directory of Open Access Journals (Sweden)

    Marisa A. N. Diaz

    2010-08-01

    Full Text Available Staphylococcus aureus is the main causative agent of bovine mastitis. The activity of several extracts from ten medicinal plants traditionally used in Brazil as antiseptic was investigated against fifteen strains of Staphylococcus aureus isolated from animals with mastitis manifestation by the disc diffusion method and broth microdilution assay. The interference of the extracts on cell in the form of adherent colonies was also evaluated. MIC values ranged from 0.5 mg/mL to 1.0 mg/mL and biofilm inhibitory concentration (BIC were between 0.25 mg/mL and 0.8 mg/mL. Results revealed the potential of extracts of Senna macranthera, Artemisia absinthium, Cymbopogon nardus and Baccharis dracunculifolia as antibacterial agents against S. aureus strains isolated from bovine mastitis and support the possible use of these phytotherapic agents in the clinical management of the disease.

  19. Isolation and identification of biosurfactant-producing strains from the genus Pseudomonas aeruginosa and antibacterial effects of biosurfactant production in vitro

    Directory of Open Access Journals (Sweden)

    Salman Ahmady-Asbchin

    2013-01-01

    Full Text Available Introduction: Biosurfactants are amphiphilic biological compounds produced extracellularly or as part of the cell membranes by a variety of microorganisms. Because of their use in various industries, they are of a particular importance. The aim of this study was to identify a strain of bacteria of the genus Pseudomonas aeruginosa biosurfactant producers. Materials and methods: In this study, different samples of oil, water and soil contaminated with oil were prepared. Hemolytic activity, emulsification activity and measurement of surface tension were used and selected strains were identified by biochemical tests. The nature and effect of antibacterial biosurfactant was evaluated for strain selection.Results: In this study, eighty eight bacterial strains were isolated. Twenty four strains were isolated from the isolated strains with hemolytic activity. Among which, 14 strains have emulsification activity more than 70% and at last four strains reached surface tension to be less than 40 mN/m. Selected strain based on biochemical tests was recognized as a Pseudomonas aeruginosa. The nature of biosurfactant was determined by TLC, and proved to be of glycolipid kind. Therefore, the produced biosurfactant of the selected strain had antibacterial activity against six bacterial infectious. Sensitive bacteria to the effects of biosurfactant extract of Pseudomonas aeruginosa83, was Staphylococcus aureus and the most resistant bacteria to these extract, was the Proteus mirabilis. The results of MIC, MBC showed that MIC of the extract in concentration of 63 and 125 mg/ml on Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus respectively. Also, the MBC were extract in concentration of 63 and 125mg/ml on Staphylococcus epidermidis and Staphylococcus aureus respectively.Discussion and conclusion: Pseudomonas aeruginosa had high potential in reducing the surface tension and biosurfactant extracted had high antibacterial effects. Therefore, it

  20. Characterization of antimicrobial resistance in Salmonella enterica strains isolated from Brazilian poultry production.

    Science.gov (United States)

    Mattiello, Samara P; Drescher, Guilherme; Barth, Valdir C; Ferreira, Carlos A S; Oliveira, Sílvia D

    2015-11-01

    Antimicrobial resistance profiles and presence of resistance determinants and integrons were evaluated in Salmonella enterica strains from Brazilian poultry. The analysis of 203 isolates showed that those from the poultry environment (88 isolates) were significantly more resistant to antimicrobials than isolates from other sources, particularly those isolated from poultry by-product meal (106 isolates). Thirty-seven isolates were resistant to at least three antimicrobial classes. Class 1 integrons were detected in 26 isolates, and the analysis of the variable region between the 5' conserved segment (CS) and 3' CS of each class 1 integron-positive isolate showed that 13 contained a typical 3' CS and 14 contained an atypical 3' CS. One Salmonella Senftenberg isolate harbored two class 1 integrons, showing both typical and atypical 3' CSs. The highest percentage of resistance was found to sulfonamides, and sul genes were detected in the majority of the resistant isolates. Aminoglycoside resistance was detected in 50 isolates, and aadA and aadB were present in 28 and 32 isolates, respectively. In addition, strA and strB were detected in 78.1 and 65.6% isolates resistant to streptomycin, respectively. Twenty-one isolates presented reduced susceptibility to β-lactams and harbored bla(TEM), bla(CMY), and/or bla(CTX-M). Forty isolates showed reduced susceptibility to tetracycline, and most presented tet genes. These results highlight the importance of the environment as a reservoir of resistant Salmonella, which may enable the persistence of resistance determinants in the poultry production chain, contributing, therefore, to the debate regarding the impacts that antimicrobial use in animal production may exert in human health.

  1. Evaluation of Antibacterial Activity of Satureja Khuzestanica J. Essential Oil against Standard and Isolated Strains of Listeria monocytogenes

    Directory of Open Access Journals (Sweden)

    Sheida Akbari-Shahabi

    2014-10-01

    Full Text Available Background: The purpose of this study was to determine antibacterial activity of essential oil of Satureja khuzestanica against Listeria monocytogenes (PTCC1295 and strains isolated from breast milk show that. Materials and Methods: In this descriptive-analytic study, Essence of leave’s plant was extracted and identified its compounds and then carvacrol was isolated. Antibacterial activities were examined by agar dilution method against L. monocytogenes. Minimum inhibitory concentration (MIC and minimum bacterial concentration (MBC were carried out by micro dilution method. Then bacterial suspension injected the BALB/c mice. Forty-eight h after seeing the listeriosis disease signs were started the treatment. Ampicillin (10 μg/disc and trimethoprim (5 g were used as controls. Results: The results showed that the inhibitory zone diameter standard and essential oils for strains isolated species were respectively 59 and 50 mm. This amount was determined by carvacrol, respectively, 60 and 48 mm. Inhibition zone diameter measurements for standard strains of ampicillin and trimethoprim tedious strains, respectively, 21, 40, 18 and 33 mm, respectively. The minimum inhibitory concentration of essential oils, carvacrol and ampicillin than standard strains, respectively 1.56, 1.56 and 155×10˗8 μg/mL and MBC 3.125, 3.125 and 125×10-7 μg/mL was determined by the ratio of the strain 3.125, 3.125 and 0.0062 μg/mL and MBC was 6.25, 6.25 and 0.025 μg/mL. Conclusion: This study showed that bacterial cleansing properties of essential oil of this plant have a strong and effective combination that is carvacrol.

  2. A study of single nucleotide polymorphism in the ystB gene of Yersinia enterocolitica strains isolated from various wild animal species.

    Science.gov (United States)

    Bancerz-Kisiel, Agata; Szczerba-Turek, Anna; Platt-Samoraj, Aleksandra; Michalczyk, Maria; Szweda, Wojciech

    2017-03-01

    Y. enterocolitica is the causative agent of yersiniosis. The objective of the article was a study of single nucleotide polymorphism in the ystB gene of Y. enterocolitica strains isolated from various wild animal species. High-resolution melting (HRM) analysis was applied to identify single nucleotide polymorphism (SNP) of ystB gene fragments of 88 Y. enterocolitica biotype 1A strains isolated from wild boar, roe deer, red deer and wild ducks. HRM analysis revealed 14 different melting profiles - 4 of them were defined as regular genotypes (G1, G2, G3, G4), whereas 10 as variations. 24 of the examined Y. enterocolitica strains were classified as G1, 18 strains as a G2, 21 strains as a G3, and 15 strains as a G4. Nucleotide sequences classified as G1 revealed 100% similarity with the Y. enterocolitica D88145.1 sequence (NCBI). Analysis of G2 revealed one point mutation - transition T111A. One mutation was also found in G3, but SNP was placed in a different gene region - transition G193A. Two SNPs - transitions G92C and T111A - were identified in G4. Direct sequencing of 10 variations revealed 5 new variants of the ystB nucleotide sequence: V1 - transition G129A (3 strains); V2 - transitions T111A and G193A (2 strains); V3 - transitions C118T and G193A (1 strain); V4 - transitions C141A and G193A (2 strains); and V5 characterized by 19 SNPs: G83A, T93A, A109G, G114T, C116T, A123G, T134C, T142G, T144C, A150C, G162A, T165G, T170G, T174A, T177G, G178A, A179G, A184G and G193A (2 strains). The predominant genotype in isolates from wild ducks was G1; in red deer G2; in wild boar G3; in roe deer G1 and G4. The proposed HRM method could be used to analyze Y. enterocolitica biotype 1A strains isolated from different sources, including humans.

  3. Detection and Characterization of Histamine-Producing Strains of Photobacterium damselae subsp. damselae Isolated from Mullets

    Directory of Open Access Journals (Sweden)

    Marcello Trevisani

    2017-06-01

    Full Text Available Photobacterium damselae subsp. damselae (Pdd is considered to be an emerging pathogen of marine fish and has also been implicated in cases of histamine food poisoning. In this study, eight strains isolated from mullets of the genera Mugil and Liza captured in the Ligurian Sea were characterized, and a method to detect histamine-producing Pdd from fish samples was developed. The histamine-producing potential of the strains was evaluated in culture media (TSB+ using a histamine biosensor. Subsequently, two strains were used to contaminate mackerel fillets (4 or 40 CFU/g, simulating a cross-contamination on the selling fish stalls. Sample homogenates were enriched in TSB+. The cultures were then inoculated on thiosulfate-citrate-bile salts-sucrose agar (TCBS and the dark green colonies were cultured on Niven agar. The violet isolates were characterized using specific biochemical and PCR based tests. All Pdd strains were histamine producers, yielding concentration varying from 167 and 8977 µg/mL in TSB+ cultures incubated at 30 °C for 24 h. Pdd colonies were detected from the inoculated mackerel samples and their histidine decarboxylase gene was amplified using species-specific primer pairs designed for this study. The results indicate that mullets can be source of Pdd and the fish retailers needs to evaluate the risk posed by cross-contamination on the selling fish stalls.

  4. Evaluating the probiotic and therapeutic potentials of Saccharomyces cerevisiae strain (OBS2) isolated from fermented nectar of toddy palm.

    Science.gov (United States)

    Srinivas, Banoth; Rani, Ganapathiwar Swarupa; Kumar, Bhukya Kiran; Chandrasekhar, Banoth; Krishna, Kommalapati Vamsi; Devi, Tangutur Anjana; Bhima, Bhukya

    2017-12-01

    The purpose of this study is to evaluate the probiotic characteristics of 15 yeast strains isolated from nectar of toddy palm. Initially, the collected samples were inoculated on yeast extract peptone dextrose agar plates and the colonies so obtained were culturally and morphologically characterized. Commercial probiotic yeast, Saccharomyces boulardii served as the control in these experiments. Of the 15 yeast strains, the isolates that were resistant to antibiotics and worked synergistically with other cultures were considered for further evaluation. Selected isolates were evaluated in vitro for tolerance to simulated gastrointestinal conditions such as temperature, pH, bile and gastric juice. Further the yeast isolates were evaluated for their pathogenicity and adherence to intestinal epithelial cells. The 2 yeast isolates with efficient probiotic properties were finally characterized by sequencing their 5.8 S rRNA and partial sequences of internal transcribed spacer 1 and 2. The sequences were BLAST searched in the National Center for Biotechnology Information, nucleic acid database for sequence similarity of organisms and phylogenetic evolutionary analysis was carried out. Based on maximum similarity of basic local alignment search tool results, organisms were characterized as Pichia kudriavzevii OBS1 (100%) and Saccharomyces cerevisiae OBS2 (96%) and sequences were finally deposited in the GenBank data library. Among these two isolates, S. cerevisiae OBS2 displayed slight/moderate antioxidant and anticancer property. Hence, strain OBS2 can be utilized and explored as a potential probiotic for therapeutic applications.

  5. Phenotypes and genotypes of erythromycin-resistant Streptococcus pyogenes strains isolated from invasive and non-invasive infections from Mexico and the USA during 1999–2010

    Science.gov (United States)

    Villaseñor-Sierra, Alberto; Katahira, Eva; Jaramillo-Valdivia, Abril N.; de los Angeles Barajas-García, María; Bryant, Amy; Morfín-Otero, Rayo; Márquez-Díaz, Francisco; Tinoco, Juan Carlos; Sánchez-Corona, José; Stevens, Dennis L.

    2012-01-01

    Summary Objective To compare the prevalence, phenotypes, and genes responsible for erythromycin resistance among Streptococcus pyogenes isolates from Mexico and the USA. Methods Eighty-nine invasive and 378 non-invasive isolates from Mexico, plus 148 invasive, 21 non-invasive, and five unclassified isolates from the USA were studied. Susceptibilities to penicillin, erythromycin, clindamycin, ceftriaxone, and vancomycin were evaluated according to Clinical and Laboratory Standards Institute (CLSI) standards. Phenotypes of erythromycin resistance were identified by triple disk test, and screening for mefA, ermTR, and ermB genes was carried out by PCR. Results All isolates were susceptible to penicillin, ceftriaxone, and vancomycin. Erythromycin resistance was found in 4.9% of Mexican strains and 5.2% of USA strains. Phenotypes in Mexican strains were 95% M and 5% cMLS; in strains from the USA, phenotypes were 33.3% iMLS, 33.3% iMLS-D, and 33.3% M. Erythromycin resistance genes in strains from Mexico were mefA (95%) and ermB (5%); USA strains harbored ermTR (56%), mefA (33%), and none (11%). In Mexico, all erythromycin-resistant strains were non-invasive, whereas 89% of strains from the USA were invasive. Conclusions Erythromycin resistance continues to exist at low levels in both Mexico and the USA, although the genetic mechanisms responsible differ between the two nations. These genetic differences may be related to the invasive character of the S. pyogenes isolated. PMID:22217469

  6. Identification of Echinococcus Granulosus Strains in Isolated Hydatid Cyst Specimens from Animals by PCR-RFLP Method in West Azerbaijan – Iran

    Directory of Open Access Journals (Sweden)

    Haleh Hanifian

    2013-09-01

    Full Text Available Background: The aim of this study was DNA extraction from protosco­lecses of Echinococcus granulosus and identification of these strains in West-Azerbai­jan Province, north western Iran.Methods: Thirty one livestock isolates from sheep and cattle were collected from abattoirs of the province. To investigate the genetic variation of the isolates, after DNA extraction by Glass beads-phenol chloroform method; PCR-RLFP analysis of rDNA-ITS1 was performed using three different restric­tion enzymes of Taq 1, Rsa 1 and Alu 1.Result: Amplified PCR products for all isolates were 1000bp band which is expected band in sheep strains (G1-G3 complex. The results of RFLP analy­sis also were the same for all isolates. PCR-RFLP patterns restriction en­zymes were identical as follows, Rsa1 bands under UV showed two bands approximately 655bp and 345bp. Alu1 bands were as follows: two approx­imately 800bp and 200bp and Taq1 did not cut any region and bands were approximately 1000 bp in all samples.Conclusions: Based on PCR-RFLP patterns of ITS1 fragment produced with endonucleases enzyme digestion in animal isolates, it can be concluded that a single strain of E. granulosus (sheep strain or G1-G3 complex is domi­nant genotype in this province

  7. Light affects fumonisin production in strains of Fusarium fujikuroi, Fusarium proliferatum, and Fusarium verticillioides isolated from rice.

    Science.gov (United States)

    Matić, Slavica; Spadaro, Davide; Prelle, Ambra; Gullino, Maria Lodovica; Garibaldi, Angelo

    2013-09-16

    Three Fusarium species associated with bakanae disease of rice (Fusarium fujikuroi, Fusarium proliferatum, and Fusarium verticillioides) were investigated for their ability to produce fumonisins (FB1 and FB2) under different light conditions, and for pathogenicity. Compared to darkness, the conditions that highly stimulated fumonisin production were yellow and green light in F. verticillioides strains; white and blue light, and light/dark alternation in F. fujikuroi and F. proliferatum strains. In general, all light conditions positively influenced fumonisin production with respect to the dark. Expression of the FUM1 gene, which is necessary for the initiation of fumonisin production, was in accordance with the fumonisin biosynthetic profile. High and low fumonisin-producing F. fujikuroi strains showed typical symptoms of bakanae disease, abundant fumonisin-producing F. verticillioides strains exhibited chlorosis and stunting of rice plants, while fumonisin-producing F. proliferatum strains were asymptomatic on rice. We report that F. fujikuroi might be an abundant fumonisin producer with levels comparable to that of F. verticillioides and F. proliferatum, highlighting the need of deeper mycotoxicological analyses on rice isolates of F. fujikuroi. Our results showed for the first time the influence of light on fumonisin production in isolates of F. fujikuroi, F. proliferatum, and F. verticillioides from rice. © 2013 Elsevier B.V. All rights reserved.

  8. Isolation, identification, and the growth promoting effects of two antagonistic actinomycete strains from the rhizosphere of Mikania micrantha Kunth.

    Science.gov (United States)

    Han, Dandan; Wang, Lanying; Luo, Yanping

    2018-03-01

    Actinomycetes are an important group of gram-positive bacteria that play an essential role in the rhizosphere ecosystem. The confrontation culture and Oxford cup method were used to evaluate the antagonistic activities of strains, which were isolated from the rhizosphere soil of Mikania micrantha. The two isolates were identified using morphological and physiological tests combined with 16S rRNA-based molecular analysis, respectively. The type I polyketone synthase (PKS-I) was amplified. The constituents of fermentation metabolites were analyzed by gas chromatography mass spectrometry. The plant growth promoting effect was determined. Finally, the growth of wheat seedlings was assessed using the Petri dish method. Overall, of the isolated twelve strains, WZS1-1 and WZS2-1 could significantly inhibit target fungi. Isolate WZS1-1 was identified as Streptomyces rochei, and WZS2-1 was identified as Streptomyces sundarbansensis. In particular, Fusarium graminearum (FG) from wheat was inhibited by more than 80%, and the inhibitory bandwidths against FG were 31 ± 0.3 mm and 19 ± 0.5 mm, respectively. The genes PKS-I were successfully amplified, confirming that these strains are capable of producing biosynthetic secondary metabolites. Major component analysis revealed aliphatic ketones, carboxylic acids, and esters, with n-hexadecanoic acid being the most abundant compound. Plant growth promoting test indicated that both strains produced IAA, presented with orange loops on CAS plates, dissolved phosphorus and potassium, fixed nitrogen, but did not generate organic acids; both strains colonized in soil, while only WZS1-1 colonized in wheat roots. Additionally, the fermentation broth significantly promoted the growth of wheat. Copyright © 2018 Elsevier GmbH. All rights reserved.

  9. Genomic, transcriptomic, and proteomic approaches towards understanding the molecular mechanisms of salt tolerance in Frankia strains isolated from Casuarina trees.

    Science.gov (United States)

    Oshone, Rediet; Ngom, Mariama; Chu, Feixia; Mansour, Samira; Sy, Mame Ourèye; Champion, Antony; Tisa, Louis S

    2017-08-18

    Soil salinization is a worldwide problem that is intensifying because of the effects of climate change. An effective method for the reclamation of salt-affected soils involves initiating plant succession using fast growing, nitrogen fixing actinorhizal trees such as the Casuarina. The salt tolerance of Casuarina is enhanced by the nitrogen-fixing symbiosis that they form with the actinobacterium Frankia. Identification and molecular characterization of salt-tolerant Casuarina species and associated Frankia is imperative for the successful utilization of Casuarina trees in saline soil reclamation efforts. In this study, salt-tolerant and salt-sensitive Casuarina associated Frankia strains were identified and comparative genomics, transcriptome profiling, and proteomics were employed to elucidate the molecular mechanisms of salt and osmotic stress tolerance. Salt-tolerant Frankia strains (CcI6 and Allo2) that could withstand up to 1000 mM NaCl and a salt-sensitive Frankia strain (CcI3) which could withstand only up to 475 mM NaCl were identified. The remaining isolates had intermediate levels of salt tolerance with MIC values ranging from 650 mM to 750 mM. Comparative genomic analysis showed that all of the Frankia isolates from Casuarina belonged to the same species (Frankia casuarinae). Pangenome analysis revealed a high abundance of singletons among all Casuarina isolates. The two salt-tolerant strains contained 153 shared single copy genes (most of which code for hypothetical proteins) that were not found in the salt-sensitive(CcI3) and moderately salt-tolerant (CeD) strains. RNA-seq analysis of one of the two salt-tolerant strains (Frankia sp. strain CcI6) revealed hundreds of genes differentially expressed under salt and/or osmotic stress. Among the 153 genes, 7 and 7 were responsive to salt and osmotic stress, respectively. Proteomic profiling confirmed the transcriptome results and identified 19 and 8 salt and/or osmotic stress-responsive proteins in the

  10. Serological characterization of Actinobacillus pleuropneumoniae biotype 2 strains isolated from pigs in two Danish herds

    DEFF Research Database (Denmark)

    Nielsen, R.; Andresen, Lars Ole; Plambeck, Tamara

    1997-01-01

    Eight Actinobacillus pleuropneumoniae biotype 2 strains were isolated in pure culture from lungs of pigs originating from two Danish herds with growing and finishing pigs. The antigenic properties were studied by indirect haemagglutination (IHA) and immunodiffusion (ID) tests using soluble surface...

  11. Molecular investigation of virulence factors of Brucella melitensis and Brucella abortus strains isolated from clinical and non-clinical samples.

    Science.gov (United States)

    Mirnejad, Reza; Jazi, Faramarz Masjedian; Mostafaei, Shayan; Sedighi, Mansour

    2017-08-01

    Brucella is zoonotic pathogen that induces abortion and sterility in domestic mammals and chronic infections in humans called Malta fever. It is a facultative intracellular potential pathogen with high infectivity. The virulence of Brucella is dependent upon its potential virulence factors such as enzymes and cell envelope associated virulence genes. The aim of this study was to investigate the Brucella virulence factors among strains isolated from humans and animals in different parts of Iran. Seventy eight strains of Brucella species isolated from suspected human and animal cases from several provinces of Iran during 2015-2016 and identified by phenotypic and molecular methods. The multiplex-PCR (M-PCR) assay was performed in order to detect the ure, wbkA, omp19, mviN, manA and perA genes by using gene specific primers. Out of 78 isolates of Brucella spp., 57 (73%) and 21 (27%) isolates were detected as B. melitensis and B. abortus, respectively, by molecular method. The relative frequency of virulence genes ure, wbkA, omp19, mviN, manA and perA were 74.4%, 89.7%, 93.6%, 94.9%, 100% and 92.3%, respectively. Our results indicate that the most of Brucella strains isolated from this region possess high percent of virulence factor genes (ure, wbkA, omp19, mviN, manA and perA) in their genome. So, each step of infection can be mediated by a number of virulence factors and each strain may have a unique combination of these factors that affected the rate of bacterial pathogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. [Isolation of a methanol-utilizing strain and its application for determining methanol].

    Science.gov (United States)

    Guo, Jun; Gao, Wei; Zhang, Qiang; Qu, Fei; Lu, Dongtao; Zheng, Jun; Pang, Jinmei; Yang, Yujing

    2013-08-04

    To isolate and characterize bacteria that can be used todevelop microbial biosensor for methanol (MeOH) determination. We used selective medium and streak plate to isolate bacteria. Morphological, physiological characteristics and 16S rDNA sequence analysis were used to identify the strain. An MeOH biosensor was then developed by immobilizing M211 along with dissolved oxygen (O2) sensor. An MeOH utilizing bacterium was isolated from biogas-producing tank using methanol as the sole carbon source, and identified as Methylobacteriumorganophilium. Decrease of O2 concentration is linearly related to the MeOH concentration in the range from 0.02% to 1%, with the MeOH detection limit of 0.27 mg/L. The response time of the biosensor is within 20 min. Furthermore, the result of interference test and the detection of methanol sample are both satisfactory. Good results are obtained in interference test and the detection of methanol sample. The proposed method seems very attractive in monitoring methanol.

  13. Molecular characterization and phylogenetic analysis of highly pathogenic Vibrio alginolyticus strains isolated during mortality outbreaks in cultured Ruditapes decussatus juvenile.

    Science.gov (United States)

    Mechri, Badreddine; Monastiri, Abir; Medhioub, Amel; Medhioub, Mohamed Nejib; Aouni, Mahjoub

    2017-10-01

    In the summer of 2008 and 2009, a series of mortalities in growing out seeds of R. decussatus juveniles were occurred in the eastern Tunisian littoral. Nine predominant bacterial strains were isolated from dead and moribund juveniles and characterized as Vibrio alginolyticus. These isolates were subjected to biochemical and molecular characterization. All the Vibrio strains were tested for their susceptibility against the most widely used antibiotic in aquaculture as well as, the assessment of the presence of erythromycin (emrB) and tetracycline (tetS) resistance genes among the tested bacteria. The degree of genetic relatedness between V. alginolyticus strains was evaluated on the basis of the Entero-Bacterial Repetitive Intergenic Consensus (ERIC) and the Random Amplification of Polymorphic DNA-PCR (RAPD-PCR) approaches. We also looked for siderophore activity and the ability to grow under iron limitation. Furthermore, the pathogenic potential of the tested isolates was evaluated using R. decussatus larva and juveniles as infection models. On antimicrobial susceptibility test, Vibrio strains exhibited total resistance to at least four antibiotics. The MICs data revealed that flumequine and oxolinic acid were the most effective antibiotics to control the studied bacteria. Results also showed that studied antibiotics resistance genes were widely disseminated in the genome of V. alginolyticus strains. Both ERIC and RAPD-PCR fingerprinting showed the presence of genetic variation among Vibrio isolates. However, RAPD typing exhibited a higher discriminative potential than ERIC-PCR. Besides, we reported here for the first time the co-production of catechol and hydroxamte by V. alginolyticus species. The challenge experiment showed that most of Vibrio isolates caused high mortality rates for both larva and juveniles at 48-h post-exposure to a bacterial concentration of 10 6  CFU/ml. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. GyrA and/or ParC alterations of Haemophilus influenzae strains isolated from the urethra of men with acute urethritis.

    Science.gov (United States)

    Kondo, Hiromi; Ito, Shin; Hatazaki, Kyoko; Horie, Kengo; Nakane, Keita; Mizutani, Kosuke; Tsuchiya, Tomohiro; Yasuda, Mitsuru; Yokoi, Shigeaki; Nakano, Masahiro; Deguchi, Takashi

    2018-03-01

    Of 73 clinical strains of Haemophilus influenzae isolated from the urethra of men with urogenital infections, we enrolled 6 strains (8.2%) with levofloxacin (LVFX) minimum inhibitory concentrations (MICs) of ≥0.03 μg/ml in this study. All the strains were isolated from non-gonococcal urethritis (NGU). We amplified the quinolone resistance-determining region of the gyrA gene and the analogous region of the parC gene from bacterial DNAs by PCR and sequenced the PCR products. Two strains with a LVFX MIC of 0.03 μg/ml had an amino acid change of Asp88 to Gly in GyrA. One with a LVFX MIC of 0.06 μg/ml had a change of Asp88 to Tyr in GyrA. Two with respective LVFX MICs of 0.12 and 0.25 μg/ml had a change of Ser84 to Leu in GyrA. One with a LVFX MIC of 1 μg/ml had changes of Ser84 to Leu in GyrA and of Ser84 to Ile in ParC. Multilocus sequence typing showed two strains with a change of Asp88 to Gly in GyrA had the same sequence type, but the others had sequence types different from each other. Single amino acid changes in GyrA alone or single changes in both GyrA and ParC could contribute to decreased susceptibility to fluoroquinolones in H. influenzae isolates from NGU. Most of the isolates with GyrA and/or ParC alterations would be multiclonal. The prevalence of such isolates would be relatively low, and they would still be susceptible to fluoroquinolones commonly prescribed for treatment of NGU. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  15. Examination of the technological properties of newly isolated strains of the genus Lactobacillus and possibilities for their application in the composition of starters

    OpenAIRE

    Denkova, Rositsa; Ilieva, Svetla; Denkova, Zapryana; Georgieva, Ljubka; Krastanov, Albert

    2014-01-01

    The ability of four Lactobacillus strains ? Lactobacillus brevis LBRZ7 (isolated from fermented cabbage), Lactobacillus plantarum LBRZ12 (isolated from fermented cabbage), Lactobacillus fermentum LBRH9 (of human origin) and Lactobacillus casei ssp. rhamnosus LBRC11 (isolated from home-made cheese) ? to grow in flour/water environment and to accumulate high concentrations of viable cells was examined. Two starters for sourdough were created for lab-scale production of wheat bread: a two-strain...

  16. Genome Sequence of Vibrio campbellii Strain UMTGB204, a Marine Bacterium Isolated from a Green Barrel Tunicate

    Science.gov (United States)

    Gan, Huan You; Noor, Mohd Ezhar Mohd; Saari, Nur Azna; Musa, Najiah; Mustapha, Baharim; Usup, Gires

    2015-01-01

    Vibrio campbellii strain UMTGB204 was isolated from a green barrel tunicate. The genome of this strain comprises 5,652,224 bp with 5,014 open reading frames, 9 rRNAs, and 116 tRNAs. It contains genes related to virulence and environmental tolerance. Gene clusters for the biosynthesis of nonribosomal peptides and bacteriocin were also identified. PMID:25814609

  17. Classification of varieties of pasteurella pestis strains isolated in the interior of the state of Pernambuco-Brazil

    Directory of Open Access Journals (Sweden)

    Dalva A. Mello

    1969-01-01

    Full Text Available Studies were made on the biochemical behavior of 100 strains of P.pestis isolated in Northeastern Brazil with regard to production of nitrous acid, reduction of nitrates to nitrltes, and aciáification of glycerol. Results showed that 98 strains can be classified as "orientalis variety", while the remaining two could not be included in any of the existing "varieties".

  18. Influence of gamma-rays and some cultural conditions on the enhancement of cellulase production by some fungal strains isolated from cellulosic wastes

    International Nuclear Information System (INIS)

    Aziz, N.H.; Abo-State, M.A.; Girigs, A.M.P.; Youssef, Kh.A.; El-Mahalawy, A.A.

    2010-01-01

    In the present study, out of 51 fungal strains isolated from the cellulosic wastes, only 19 were CMCase-producers. Aspergillus, Fusarium and Penicillium were the most common fungal genera isolated from the cellulosic wastes. Fusarium neoceras, Aspergillus fumigatus and Fusarium oxysporium produced CMCase activity than Trichoderma viride. Out of 23 gamma-irradiated survivors from A.fumigatus and F. neoceras showing CMCase production, only two mutant strains A.fumigatus 8G-2 and F. neoceras 4G-2 produced the highest levels of CMCase than the parent strains. The results indicated that the maximum level of of CMCase activity was produced by A.fumigatus and F. neoceras strains under optiminizing conditions.

  19. Antigenic specificity and morphologic characteristics of Chlamydia trachomatis, strain SFPD, isolated from hamsters with proliferative ileitis.

    Science.gov (United States)

    Fox, J G; Stills, H F; Paster, B J; Dewhirst, F E; Yan, L; Palley, L; Prostak, K

    1993-10-01

    Profound diarrhea associated with proliferating intestinal cells containing intraepithelial campylobacter-like organisms (ICLO) occurs in a variety of mammalian hosts, particularly swine and hamsters. Recently, intracellular bacteria were isolated from proliferative intestinal tissue of hamsters and propagated in intestine cell line 407. Oral inoculation of hamsters with cell culture lysates containing these organisms reproduced the disease in susceptible hamsters. In the present study, an intracellular bacterium from the INT 407 cell line was shown by a variety of techniques to be a member of the genus Chlamydia and has been designated Chlamydia sp. strain SFPD. McCoy cells infected with Chlamydia sp. strain SFPD demonstrated bright fluorescent-stained intracytoplasmic inclusions when examined with fluorescein-labeled species-specific C. trachomatis monoclonal antibodies. The organism also reacted to fluorescein-labeled polyclonal but not monoclonal ICLO "omega" antisera. Ultrastructural examination of the Chlamydia sp. strain SFPD from McCoy cells revealed electrondense elementary bodies and a less electron-dense reticulate-like body that was circular; both features are consistent in morphology to developmental forms of Chlamydia and do not conform to ICLO morphology. Molecular studies, 16S ribosomal sequence analysis, and sequencing of the outer membrane protein confirmed that the isolate is a C. trachomatis closely related to the mouse pneumonitis strain of C. trachomatis.

  20. Complete genome sequence of Vibrio anguillarum strain NB10, a virulent isolate from the Gulf of Bothnia.

    Science.gov (United States)

    Holm, Kåre Olav; Nilsson, Kristina; Hjerde, Erik; Willassen, Nils-Peder; Milton, Debra L

    2015-01-01

    Vibrio anguillarum causes a fatal hemorrhagic septicemia in marine fish that leads to great economical losses in aquaculture world-wide. Vibrio anguillarum strain NB10 serotype O1 is a Gram-negative, motile, curved rod-shaped bacterium, isolated from a diseased fish on the Swedish coast of the Gulf of Bothnia, and is slightly halophilic. Strain NB10 is a virulent isolate that readily colonizes fish skin and intestinal tissues. Here, the features of this bacterium are described and the annotation and analysis of its complete genome sequence is presented. The genome is 4,373,835 bp in size, consists of two circular chromosomes and one plasmid, and contains 3,783 protein-coding genes and 129 RNA genes.