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Sample records for bacterial isolate stenotrophomonas

  1. A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles

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    Shekhawat G

    2009-07-01

    Full Text Available Abstract Background The synthesis of gold nanoparticles (GNPs has received considerable attention with their potential applications in various life sciences related applications. Recently, there has been tremendous excitement in the study of nanoparticles synthesis by using some natural biological system, which has led to the development of various biomimetic approaches for the growth of advanced nanomaterials. In the present study, we have demonstrated the synthesis of gold nanoparticles by a novel bacterial strain isolated from a site near the famous gold mines in India. A promising mechanism for the biosynthesis of GNPs by this strain and their stabilization via charge capping was investigated. Results A bacterial isolate capable of gold nanoparticle synthesis was isolated and identified as a novel strain of Stenotrophomonas malophilia (AuRed02 based on its morphology and an analysis of its 16S rDNA gene sequence. After 8 hrs of incubation, monodisperse preparation of gold nanoparticles was obtained. Gold nanoparticles were characterized and found to be of ~40 nm size. Electrophoresis, Zeta potential and FTIR measurements confirmed that the particles are capped with negatively charged phosphate groups from NADP rendering them stable in aqueous medium. Conclusion The process of synthesis of well-dispersed nanoparticles using a novel microorganism isolated from the gold enriched soil sample has been reported in this study, leading to the development of an easy bioprocess for synthesis of GNPs. This is the first study in which an extensive characterization of the indigenous bacterium isolated from the actual gold enriched soil was conducted. Promising mechanism for the biosynthesis of GNPs by the strain and their stabilization via charge capping is suggested, which involves an NADPH-dependent reductase enzyme that reduces Au3+ to Au0 through electron shuttle enzymatic metal reduction process.

  2. A novel bacterial isolate Stenotrophomonas maltophilia as living factory for synthesis of gold nanoparticles.

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    Nangia, Yogesh; Wangoo, Nishima; Goyal, Nisha; Shekhawat, G; Suri, C Raman

    2009-07-20

    The synthesis of gold nanoparticles (GNPs) has received considerable attention with their potential applications in various life sciences related applications. Recently, there has been tremendous excitement in the study of nanoparticles synthesis by using some natural biological system, which has led to the development of various biomimetic approaches for the growth of advanced nanomaterials. In the present study, we have demonstrated the synthesis of gold nanoparticles by a novel bacterial strain isolated from a site near the famous gold mines in India. A promising mechanism for the biosynthesis of GNPs by this strain and their stabilization via charge capping was investigated. A bacterial isolate capable of gold nanoparticle synthesis was isolated and identified as a novel strain of Stenotrophomonas malophilia (AuRed02) based on its morphology and an analysis of its 16S rDNA gene sequence. After 8 hrs of incubation, monodisperse preparation of gold nanoparticles was obtained. Gold nanoparticles were characterized and found to be of ~40 nm size. Electrophoresis, Zeta potential and FTIR measurements confirmed that the particles are capped with negatively charged phosphate groups from NADP rendering them stable in aqueous medium. The process of synthesis of well-dispersed nanoparticles using a novel microorganism isolated from the gold enriched soil sample has been reported in this study, leading to the development of an easy bioprocess for synthesis of GNPs. This is the first study in which an extensive characterization of the indigenous bacterium isolated from the actual gold enriched soil was conducted. Promising mechanism for the biosynthesis of GNPs by the strain and their stabilization via charge capping is suggested, which involves an NADPH-dependent reductase enzyme that reduces Au3+ to Au0 through electron shuttle enzymatic metal reduction process.

  3. Biotransformation of tetracycline by a novel bacterial strain Stenotrophomonas maltophilia DT1.

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    Leng, Yifei; Bao, Jianguo; Chang, Gaofeng; Zheng, Han; Li, Xingxing; Du, Jiangkun; Snow, Daniel; Li, Xu

    2016-11-15

    Although several abiotic processes have been reported that can transform antibiotics, little is known about whether and how microbiological processes may degrade antibiotics in the environment. This work isolated one tetracycline degrading bacterial strain, Stenotrophomonas maltophilia strain DT1, and characterized the biotransformation of tetracycline by DT1 under various environmental conditions. The biotransformation rate was the highest when the initial pH was 9 and the reaction temperature was at 30°C, and can be described using the Michaelis-Menten model under different initial tetracycline concentrations. When additional substrate was present, the substrate that caused increased biomass resulted in a decreased biotransformation rate of tetracycline. According to disk diffusion tests, the biotransformation products of tetracycline had lower antibiotic potency than the parent compound. Six possible biotransformation products were identified, and a potential biotransformation pathway was proposed that included sequential removal of N-methyl, carbonyl, and amine function groups. Results from this study can lead to better estimation of the fate and transport of antibiotics in the environment and has the potential to be utilized in designing engineering processes to remove tetracycline from water and soil. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Comparison of two multimetal resistant bacterial strains: Enterobacter sp. YSU and Stenotrophomonas maltophilia ORO2.

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    Holmes, Andrew; Vinayak, Anubhav; Benton, Cherise; Esbenshade, Aaron; Heinselman, Carlisle; Frankland, Daniel; Kulkarni, Samatha; Kurtanich, Adrienne; Caguiat, Jonathan

    2009-11-01

    The Y-12 plant in Oak Ridge, TN, which manufactured nuclear weapons during World War II and the Cold War, contaminated East Fork Poplar Creek with heavy metals. The multimetal resistant bacterial strain, Stenotrophomonas maltophilia Oak Ridge strain O2 (S. maltophilia O2), was isolated from East Fork Poplar Creek. Sequence analysis of 16s rDNA suggested that our working strain of S. maltophilia O2 was a strain of Enterobacter. Phylogenetic tree analysis and biochemical tests confirmed that it belonged to an Enterobacter species. This new strain was named Enterobacter sp. YSU. Using a modified R3A growth medium, R3A-Tris, the Hg(II), Cd(II), Zn(II), Cu(II), Au(III), Cr(VI), Ag(I), As(III), and Se(IV) MICs for a confirmed strain of S. maltophilia O2 were 0.24, 0.33, 5, 5, 0.25, 7, 0.03, 14, and 40 mM, respectively, compared to 0.07, 0.24, 0.8, 3, 0.05, 0.4, 0.08, 14, and 40 mM, respectively, for Enterobacter sp. YSU. Although S. maltophilia O2 was generally more metal resistant than Enterobacter sp. YSU, in comparison to Escherichia coli strain HB101, Enterobacter sp. YSU was resistant to Hg(II), Cd(II), Zn(II), Au(III), Ag(I), As(III), and Se(IV). By studying metal resistances in these two strains, it may be possible to understand what makes one microorganism more metal resistant than another microorganism. This work also provided benchmark MICs that can be used to evaluate the metal resistance properties of other bacterial isolates from East Fork Poplar Creek and other metal contaminated sites.

  5. Isolation of New Stenotrophomonas Bacteriophages and Genomic Characterization of Temperate Phage S1▿

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    García, Pilar; Monjardín, Cristina; Martín, Rebeca; Madera, Carmen; Soberón, Nora; Garcia, Eva; Meana, Álvaro; Suárez, Juan E.

    2008-01-01

    Twenty-two phages that infect Stenotrophomonas species were isolated through sewage enrichment and prophage induction. Of them, S1, S3, and S4 were selected due to their wide host ranges compared to those of the other phages. S1 and S4 are temperate siphoviruses, while S3 is a virulent myovirus. The genomes of S3 and S4, about 33 and 200 kb, were resistant to restriction digestion. The lytic cycles lasted 30 min for S3 and about 75 min for S1 and S4. The burst size for S3 was 100 virions/cell, while S1 and S4 produced about 75 virus particles/cell. The frequency of bacteriophage-insensitive host mutants, calculated by dividing the number of surviving colonies by the bacterial titer of a parallel, uninfected culture, ranged between 10−5 and 10−6 for S3 and 10−3 and 10−4 for S1 and S4. The 40,287-bp genome of S1 contains 48 open reading frames (ORFs) and 12-bp 5′ protruding cohesive ends. By using a combination of bioinformatics and experimental evidence, functions were ascribed to 21 ORFs. The morphogenetic and lysis modules are well-conserved, but no lysis-lysogeny switch or DNA replication gene clusters were recognized. Two major clusters of genes with respect to transcriptional orientation were observed. Interspersed among them were lysogenic conversion genes encoding phosphoadenosine phosphosulfate reductase and GspM, a protein involved in the general secretion system II. The attP site of S1 may be located within a gene that presents over 75% homology to a Stenotrophomonas chromosomal determinant. PMID:18952876

  6. Survival and growth of Stenotrophomonas maltophilia in free-living amoebae (FLA) and bacterial virulence properties.

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    Denet, Elodie; Vasselon, Valentin; Burdin, Béatrice; Nazaret, Sylvie; Favre-Bonté, Sabine

    2018-01-01

    Stenotrophomonas maltophilia is found ubiquitously in the environment and is an important emerging nosocomial pathogen. S. maltophilia has been recently described as an Amoebae-Resistant Bacteria (ARB) that exists as part of the microbiome of various free-living amoebae (FLA) from waters. Co-culture approaches with Vermamoeba vermiformis demonstrated the ability of this bacterium to resist amoebal digestion. In the present study, we assessed the survival and growth of six environmental and one clinical S. maltophilia strains within two amoebal species: Acanthamoeba castellanii and Willaertia magna. We also evaluated bacterial virulence properties using the social amoeba Dictyostelium discoideum. A co-culture approach was carried out over 96 hours and the abundance of S. maltophilia cells was measured using quantitative PCR and culture approach. The presence of bacteria inside the amoeba was confirmed using confocal microscopy. Our results showed that some S. maltophilia strains were able to multiply within both amoebae and exhibited multiplication rates up to 17.5 and 1166 for A. castellanii and W. magna, respectively. In contrast, some strains were unable to multiply in either amoeba. Out of the six environmental S. maltophilia strains tested, one was found to be virulent. Surprisingly, this strain previously isolated from a soil amoeba, Micriamoeba, was unable to infect both amoebal species tested. We further performed an assay with a mutant strain of S. maltophilia BurA1 lacking the efflux pump ebyCAB gene and found the mutant to be more virulent and more efficient for intra-amoebal multiplication. Overall, the results obtained strongly indicated that free-living amoebae could be an important ecological niche for S. maltophilia.

  7. Survival and growth of Stenotrophomonas maltophilia in free-living amoebae (FLA and bacterial virulence properties.

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    Elodie Denet

    Full Text Available Stenotrophomonas maltophilia is found ubiquitously in the environment and is an important emerging nosocomial pathogen. S. maltophilia has been recently described as an Amoebae-Resistant Bacteria (ARB that exists as part of the microbiome of various free-living amoebae (FLA from waters. Co-culture approaches with Vermamoeba vermiformis demonstrated the ability of this bacterium to resist amoebal digestion. In the present study, we assessed the survival and growth of six environmental and one clinical S. maltophilia strains within two amoebal species: Acanthamoeba castellanii and Willaertia magna. We also evaluated bacterial virulence properties using the social amoeba Dictyostelium discoideum. A co-culture approach was carried out over 96 hours and the abundance of S. maltophilia cells was measured using quantitative PCR and culture approach. The presence of bacteria inside the amoeba was confirmed using confocal microscopy. Our results showed that some S. maltophilia strains were able to multiply within both amoebae and exhibited multiplication rates up to 17.5 and 1166 for A. castellanii and W. magna, respectively. In contrast, some strains were unable to multiply in either amoeba. Out of the six environmental S. maltophilia strains tested, one was found to be virulent. Surprisingly, this strain previously isolated from a soil amoeba, Micriamoeba, was unable to infect both amoebal species tested. We further performed an assay with a mutant strain of S. maltophilia BurA1 lacking the efflux pump ebyCAB gene and found the mutant to be more virulent and more efficient for intra-amoebal multiplication. Overall, the results obtained strongly indicated that free-living amoebae could be an important ecological niche for S. maltophilia.

  8. Studies on hydrocarbon degradation by the bacterial isolate ...

    African Journals Online (AJOL)

    The hydrocarbon utilizing capability of Stenotrophomonas rhizophila (PM-1), isolated from oil contaminated soil composts from Western Ghats region of Karnataka was analyzed. In the bioremediation experiment, ONGC heavy crude oil and poly aromatic hydrocarbons (PAHs) utilization by the bacterial isolate was studied.

  9. An MLSA-based online scheme for the rapid identification of Stenotrophomonas isolates

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    Patrícia Locosque Ramos

    2011-06-01

    Full Text Available An online scheme to assign Stenotrophomonas isolates to genomic groups was developed using the multilocus sequence analysis (MLSA, which is based on the DNA sequencing of selected fragments of the housekeeping genes ATP synthase alpha subunit (atpA, the recombination repair protein (recA, the RNA polymerase alpha subunit (rpoA and the excision repair beta subunit (uvrB. This MLSA-based scheme was validated using eight of the 10 Stenotrophomonas species that have been previously described. The environmental and nosocomial Stenotrophomonas strains were characterised using MLSA, 16S rRNA sequencing and DNA-DNA hybridisation (DDH analyses. Strains of the same species were found to have greater than 95% concatenated sequence similarity and specific strains formed cohesive readily recognisable phylogenetic groups. Therefore, MLSA appeared to be an effective alternative methodology to amplified fragment length polymorphism fingerprint and DDH techniques. Strains of Stenotrophomonas can be readily assigned through the open database resource that was developed in the current study (www.steno.lncc.br/.

  10. The isolation and characterization of two Stenotrophomonas maltophilia bacteriophages capable of cross-taxonomic order infectivity.

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    Peters, Danielle L; Lynch, Karlene H; Stothard, Paul; Dennis, Jonathan J

    2015-09-03

    A rapid worldwide increase in the number of human infections caused by the extremely antibiotic resistant bacterium Stenotrophomonas maltophilia is prompting alarm. One potential treatment solution to the current antibiotic resistance dilemma is "phage therapy", the clinical application of bacteriophages to selectively kill bacteria. Towards that end, phages DLP1 and DLP2 (vB_SmaS-DLP_1 and vB_SmaS-DLP_2, respectively) were isolated against S. maltophilia strain D1585. Host range analysis for each phage was conducted using 27 clinical S. maltophilia isolates and 11 Pseudomonas aeruginosa strains. Both phages exhibit unusually broad host ranges capable of infecting bacteria across taxonomic orders. Transmission electron microscopy of the phage DLP1 and DLP2 morphology reveals that they belong to the Siphoviridae family of bacteriophages. Restriction fragment length polymorphism analysis and complete genome sequencing and analysis indicates that phages DLP1 and DLP2 are closely related but different phages, sharing 96.7 % identity over 97.2 % of their genomes. These two phages are also related to P. aeruginosa phages vB_Pae-Kakheti_25 (PA25), PA73, and vB_PaeS_SCH_Ab26 (Ab26) and more distantly related to Burkholderia cepacia complex phage KL1, which together make up a taxonomic sub-family. Phages DLP1 and DLP2 exhibited significant differences in host ranges and growth kinetics. The isolation and characterization of phages able to infect two completely different species of bacteria is an exciting discovery, as phages typically can only infect related bacterial species, and rarely infect bacteria across taxonomic families, let alone across taxonomic orders.

  11. Identification of Stenotrophomonas maltophilia strains isolated from environmental and clinical samples: a rapid and efficient procedure.

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    Pinot, C; Deredjian, A; Nazaret, S; Brothier, E; Cournoyer, B; Segonds, C; Favre-Bonté, S

    2011-11-01

    Aim of the study is to identify accurately Stenotrophomonas maltophilia isolates recovered from environmental and clinical samples. Recovery of Sten. maltophilia-like isolates from soil samples using the vancomycin, imipenem, amphotericin B (VIA) selective agar medium enabled distinction of various morphotype colonies. A set of soil and clinical isolates was tested for species identification using different methods. 16S rDNA analyses showed the dark green with a blue halo morphotype to be typical Sten. maltophilia strains. The API-20NE, Vitek-2 and Biolog phenotypic analyses typically used for the identification of clinical isolates did not perform well on these soil isolates. The species-specific PCR screening targeting Sten. maltophilia 23S rDNA and the multiplex smeD/ggpS PCR, differentiating Sten. maltophilia from Stenotrophomonas rhizophila, were tested for improvement of these identification schemes. The latter multiplex PCR identified all isolates tested in this study, whatever be their origin. Isolation on VIA medium and confirmation of Sten. maltophilia species membership by smeD PCR is proposed to identify environmental and clinical isolates of Sten. maltophilia. The proposed approach enables isolation and identification of Sten. maltophilia from different environments in an easy and rapid way. This approach will be useful to accurately manage studies on the abundance and distribution of Sten. maltophilia in hospital and nonhospital environments. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  12. Stenotrophomonas maltophilia and Vermamoeba vermiformis relationships: bacterial multiplication and protection in amoebal-derived structures.

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    Cateau, Estelle; Maisonneuve, Elodie; Peguilhan, Samuel; Quellard, Nathalie; Hechard, Yann; Rodier, Marie-Helene

    2014-12-01

    Stenotrophomonas maltophilia, a bacteria involved in healthcare-associated infections, can be found in hospital water systems. Other microorganisms, such as Free Living amoebae (FLA), are also at times recovered in the same environment. Amongst these protozoa, many authors have reported the presence of Vermamoeba vermiformis. We show here that this amoeba enhances S. maltophilia growth and harbors the bacteria in amoebal-derived structures after 28 days in harsh conditions. These results highlight the fact that particular attention should be paid to the presence of FLA in hospital water systems, because of their potential implication in survival and growth of pathogenic bacterial species. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  13. Identification of electrode respiring, hydrocarbonoclastic bacterial strain Stenotrophomonas maltophilia MK2 highlights the untapped potential for environmental bioremediation

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    Krishnaveni Venkidusamy

    2016-12-01

    Full Text Available Electrode respiring bacteria (ERB possess a great potential for many biotechnological applications such as microbial electrochemical remediation systems (MERS because of their exoelectrogenic capabilities to degrade xenobiotic pollutants. Very few ERB have been isolated from MERS, those exhibited a bioremediation potential towards organic contaminants. Here we report once such bacterial strain, Stenotrophomonas maltophilia MK2, a facultative anaerobic bacterium isolated from a hydrocarbon fed MERS, showed a potent hydrocarbonoclastic behavior under aerobic and anaerobic environments. Distinct properties of the strain MK2 were anaerobic fermentation of the amino acids, electrode respiration, anaerobic nitrate reduction and the ability to metabolize n-alkane components (C8-C36 of petroleum hydrocarbons including the biomarkers, pristine and phytane. The characteristic of diazoic dye decolorization was used as a criterion for pre-screening the possible electrochemically active microbial candidates. Bioelectricity generation with concomitant dye decolorization in MERS showed that the strain is electrochemically active. In acetate fed microbial fuel cells, maximum current density of 273±8 mA/m2 (1000Ω was produced (power density 113±7 mW/m2 by strain MK2 with a coulombic efficiency of 34.8 %. Further, the presence of possible alkane hydroxylase genes (alkB and rubA in the strain MK2 indicated that the genes involved in hydrocarbon degradation are of diverse origin. Such observations demonstrated the potential of facultative hydrocarbon degradation in contaminated environments. Identification of such a novel petrochemical hydrocarbon degrading ERB is likely to offer a new route to the sustainable bioremedial process of source zone contamination with simultaneous energy generation through MERS.

  14. The isolation and characterization of Stenotrophomonas maltophilia T4-like bacteriophage DLP6.

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    Danielle L Peters

    Full Text Available Increasing isolation of the extremely antibiotic resistant bacterium Stenotrophomonas maltophilia has caused alarm worldwide due to the limited treatment options available. A potential treatment option for fighting this bacterium is 'phage therapy', the clinical application of bacteriophages to selectively kill bacteria. Bacteriophage DLP6 (vB_SmoM-DLP6 was isolated from a soil sample using clinical isolate S. maltophilia strain D1571 as host. Host range analysis of phage DLP6 against 27 clinical S. maltophilia isolates shows successful infection and lysis in 13 of the 27 isolates tested. Transmission electron microscopy of DLP6 indicates that it is a member of the Myoviridae family. Complete genome sequencing and analysis of DLP6 reveals its richly recombined evolutionary history, featuring a core of both T4-like and cyanophage genes, which suggests that it is a member of the T4-superfamily. Unlike other T4-superfamily phages however, DLP6 features a transposase and ends with 229 bp direct terminal repeats. The isolation of this bacteriophage is an exciting discovery due to the divergent nature of DLP6 in relation to the T4-superfamily of phages.

  15. The isolation and characterization of Stenotrophomonas maltophilia T4-like bacteriophage DLP6.

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    Peters, Danielle L; Stothard, Paul; Dennis, Jonathan J

    2017-01-01

    Increasing isolation of the extremely antibiotic resistant bacterium Stenotrophomonas maltophilia has caused alarm worldwide due to the limited treatment options available. A potential treatment option for fighting this bacterium is 'phage therapy', the clinical application of bacteriophages to selectively kill bacteria. Bacteriophage DLP6 (vB_SmoM-DLP6) was isolated from a soil sample using clinical isolate S. maltophilia strain D1571 as host. Host range analysis of phage DLP6 against 27 clinical S. maltophilia isolates shows successful infection and lysis in 13 of the 27 isolates tested. Transmission electron microscopy of DLP6 indicates that it is a member of the Myoviridae family. Complete genome sequencing and analysis of DLP6 reveals its richly recombined evolutionary history, featuring a core of both T4-like and cyanophage genes, which suggests that it is a member of the T4-superfamily. Unlike other T4-superfamily phages however, DLP6 features a transposase and ends with 229 bp direct terminal repeats. The isolation of this bacteriophage is an exciting discovery due to the divergent nature of DLP6 in relation to the T4-superfamily of phages.

  16. CHROMagar COL-APSE: a selective bacterial culture medium for the isolation and differentiation of colistin-resistant Gram-negative pathogens

    DEFF Research Database (Denmark)

    Abdul Momin, Muhd Haziq F; Bean, David C; Hendriksen, Rene S.

    2017-01-01

    Purpose. A selective chromogenic culture medium for the laboratory isolation and differentiation of colistin resistant Acinetobacter, Pseudomonas, Stenotrophomonas and Enterobacteriaceae spp. (CHROMagar COL-APSE) was developed, evaluated and compared to an existing selective bacterial culture...

  17. A Secreted Ankyrin-Repeat Protein from Clinical Stenotrophomonas maltophilia Isolates Disrupts Actin Cytoskeletal Structure.

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    MacDonald, Logan C; O'Keefe, Sean; Parnes, Mei-Fan; MacDonald, Hanlon; Stretz, Lindsey; Templer, Suzanne J; Wong, Emily L; Berger, Bryan W

    2016-01-08

    Stenotrophomonas maltophilia is an emerging, multidrug-resistant pathogen of increasing importance for the immunocompromised, including cystic fibrosis patients. Despite its significance as an emerging pathogen, relatively little is known regarding the specific factors and mechanisms that contribute to its pathogenicity. We identify and characterize a putative ankyrin-repeat protein (Smlt3054) unique to clinical S. maltophilia isolates that binds F-actin in vitro and co-localizes with actin in transfected HEK293a cells. Smlt3054 is endogenously expressed and secreted from clinical S. maltophilia isolates, but not an environmental isolate (R551-3). The in vitro binding of Smlt3054 to F-actin resulted in a thickening of the filaments as observed by TEM. Ectopic expression of Smlt3054-GFP exhibits strong co-localization with F-actin, with distinct, retrograde F-actin waves specifically associated with Smlt3054 in individual cells as well as formation of dense, internal inclusions at the expense of retrograde F-actin waves. Collectively, our results point to an interaction between Smlt3054 and F-actin. Furthermore, as a potentially secreted protein unique to clinical S. maltophilia isolates, Smlt3054 may serve as a starting point for understanding the mechanisms by which S. maltophilia has become an emergent pathogen.

  18. Levofloxacin Efflux and smeD in Clinical Isolates of Stenotrophomonas maltophilia.

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    Chong, So Young; Lee, Kyungwon; Chung, Hae-Sun; Hong, Seong Geun; Suh, Younghee; Chong, Yunsop

    2017-03-01

    Trimethoprim-sulfamethoxazole is the first-line antimicrobial combination for Stenotrophomonas maltophilia infections. However, allergy or intolerance and increasing resistance limit the use of trimethoprim-sulfamethoxazole. Quinolones can be used as an alternative therapeutic option, but resistance can emerge rapidly during therapy. We analyzed the contribution of SmeABC and SmeDEF efflux pumps to levofloxacin resistance in clinical isolates of S. maltophilia. Nonduplicate clinical isolates of S. maltophilia were collected in 2010 from 11 university hospitals (n = 102). Fifty-five levofloxacin nonsusceptible (minimum inhibitory concentration [MIC] ≥4 μg/ml) and 47 susceptible (MIC ≤2 μg/ml) isolates were tested for efflux pump overexpression. Real-time reverse transcription-PCR was performed for amplification and quantification of smeB, smeC, smeD, and smeF mRNA. To determine which antimicrobials were affected by smeD overexpression, the growth rates of a levofloxacin-susceptible S. maltophilia isolate were compared by measuring absorbance of antimicrobial-supplemented Luria-Bertani broth (LB) cultures with or without triclosan. Significant relationships between sme gene overexpression and resistance were observed for smeD against levofloxacin, smeC and smeF against ceftazidime, and smeC against ticarcillin-clavulanate. The mean MICs of moxifloxacin and tigecycline did not significantly differ for isolates with or without overexpression of smeB, smeC, and smeF, but were significantly higher for isolates with smeD overexpression. The mean MICs of amikacin were significantly higher for smeC or smeF overexpressing isolates. Increased growth of a levofloxacin-susceptible isolate was observed in LB with 1/2 MIC levofloxacin in the presence of triclosan. These data suggest that the expression of smeD plays a role in levofloxacin resistance in S. maltophilia.

  19. Antibiotics resistance of Stenotrophomonas maltophilia strains isolated from various clinical specimens.

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    Çıkman, Aytekin; Parlak, Mehmet; Bayram, Yasemin; Güdücüoğlu, Hüseyin; Berktaş, Mustafa

    2016-03-01

    A limited number of antibiotics are recommended for the therapy of Stenotrophomonas maltophilia infections due to therapy difficulties caused by its numerous mechanisms of resistance. In this study conducted over a period of approximately 5 years we aimed to determine resistance rates of S. maltophilia based on drug classification recommended by Clinical and Laboratory Standards Institute. A total of 118 S. maltophilia strains isolated from various clinical specimens between January 2006 and June 2012 were included in the study. BD Phoenixautomated microbiology system (Becton Dickinson, USA) was utilized for species level identification and antibiotic susceptibility testing. Sixty seven of S. maltophilia strains were isolated from tracheal aspirate isolates, 17 from blood, 10 from sputum, 10 from wound and 14 from other clinical specimens. Levofloxacin was found to be the most effective antibiotic against S. maltophilia strains with resistance rate of 7.6%. The resistance rates to other antibiotics were as follows: chloramphenicol 18.2%, trimethoprim-sulfamethoxazole 20.3% and ceftazidime 72%. The study revealed that S. maltophilia is resistant to many antibiotics. The treatment of infections caused by S. maltophilia should be preferred primarily as levofloxacin, chloramphenicol, and TMP-SXT, respectively.

  20. Isolation and characterization of an endosulfan-degrading strain, Stenotrophomonas sp. LD-6, and its potential in soil bioremediation.

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    Yu, Fang-Bo; Shinawar, Waseem Ali; Sun, Jing-Ya; Luo, Lin-Ping

    2012-01-01

    Aerobic bacteria degrading endosulfan were isolated from contaminated sludge. One of the isolates, LD-6, was identified as Stenotrophomonas sp. The bacterium could utilize endosulfan as the sole source of carbon and sulfur. 100 mg/l endosulfan was completely degraded within 10 days, and endosulfan diol and endosulfan ether were detected as major metabolites with a slight decrease in culture pH. The results indicated that Stenotrophomonas. sp. LD-6 might degrade endosulfan by a non-oxidative pathway. Biodegradation of both isomers was relatively better at a temperature range of 25-35 degrees C, with a maximum at 30 degrees C. In addition, cell crude extract of strain LD-6 could metabolize endosulfan rapidly, and degradative enzymes were intracellular distributed and constitutively expressed. Besides, application of the strain was found to promote the removal of endosulfan in soil. This study might help with the future research in better understanding of the biodegradation.

  1. Genotyping of environmental and clinical Stenotrophomonas maltophilia isolates and their pathogenic potential.

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    Martina Adamek

    Full Text Available Stenotrophomonas maltophilia is a highly versatile species with useful biotechnological potential but also with pathogenic properties. In light of possible differences in virulence characteristics, knowledge about genomic subgroups is therefore desirable. Two different genotyping methods, rep-PCR fingerprinting and partial gyrB gene sequencing were used to elucidate S. maltophilia intraspecies diversity. Rep-PCR fingerprinting revealed the presence of 12 large subgroups, while gyrB gene sequencing distinguished 10 subgroups. For 8 of them, the same strain composition was shown with both typing methods. A subset of 59 isolates representative for the gyrB groups was further investigated with regards to their pathogenic properties in a virulence model using Dictyostelium discoideum and Acanthamoeba castellanii as host organisms. A clear tendency towards accumulation of virulent strains could be observed for one group with A. castellanii and for two groups with D. discoideum. Several virulent strains did not cluster in any of the genetic groups, while other groups displayed no virulence properties at all. The amoeba pathogenicity model proved suitable in showing differences in S. maltophilia virulence. However, the model is still not sufficient to completely elucidate virulence as critical for a human host, since several strains involved in human infections did not show any virulence against amoeba.

  2. Stenotrophomonas maltophilia

    DEFF Research Database (Denmark)

    Hansen, Christine R

    2012-01-01

    Stenotrophomonas maltophilia can cause persistent airway colonization and chronic infection in cystic fibrosis (CF) patients. The clinical effect of chronic S. maltophilia infection is still a matter of debate. The purpose of the review is to summarize studies published during the last 1.5 years...

  3. Genome Sequence of a Multidrug-Resistant Strain of Stenotrophomonas maltophilia with Carbapenem Resistance, Isolated from King Abdullah Medical City, Makkah, Saudi Arabia

    KAUST Repository

    Abdel-Haleem, Alyaa M.

    2015-10-15

    The emergence and spread of multidrug-resistant (MDR) bacteria have been regarded as major challenges among health care-associated infections worldwide. Here, we report the draft genome sequence of an MDR Stenotrophomonas maltophilia strain isolated in 2014 from King Abdulla Medical City, Makkah, Saudi Arabia.

  4. Presence of Stenotrophomonas maltophilia exhibiting high genetic similarity to clinical isolates in final effluents of pig farm wastewater treatment plants.

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    Kim, Young-Ji; Park, Jin-Hyeong; Seo, Kun-Ho

    2018-03-01

    Although the prevalence of community-acquired Stenotrophomonas maltophilia infections is sharply increasing, the sources and likely transmission routes of this bacterium are poorly understood. We studied the significance of the presence of S. maltophilia in final effluents and receiving rivers of pig farm wastewater treatment plants (WWTPs). The loads and antibiotic resistance profiles of S. maltophilia in final effluents were assessed. Antibiotic resistance determinants and biofilm formation genes were detected by PCR, and genetic similarity to clinical isolates was investigated using multilocus sequence typing (MLST). S. maltophilia was recovered from final effluents at two of three farms and one corresponding receiving river. Tests of resistance to antibiotics recommended for S. maltophilia infection revealed that for each agent, at least one isolate was classified as resistant or intermediate, with the exception of minocycline. Furthermore, multidrug resistant S. maltophilia susceptible to antibiotics of only two categories was isolated and found to carry the sul2 gene, conferring trimethoprim/sulfamethoxazole resistance. All isolates carried spgM, encoding a major factor in biofilm formation. MLST revealed that isolates of the same sequence type (ST; ST189) were present in both effluent and receiving river samples, and phylogenetic analysis showed that all of the STs identified in this study clustered with clinical isolates. Moreover, one isolate (ST192) recovered in this investigation demonstrated 99.61% sequence identity with a clinical isolate (ST98) associated with a fatal infection in South Korea. Thus, the pathogenicity of the isolates reported here is likely similar to that of those from clinical environments, and WWTPs may play a role as a source of S. maltophilia from which this bacterium spreads to human communities. To the best of our knowledge, this represents the first report of S. maltophilia in pig farm WWTPs. Our results indicate that

  5. Biosynthesis and structural characterization of silver nanoparticles from bacterial isolates

    Energy Technology Data Exchange (ETDEWEB)

    Zaki, Sahar, E-mail: saharzaki@yahoo.com [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt); El Kady, M.F. [Fabrication Technology Department, Advanced Technology and New Materials Research Institute (ATNMRI), Mubarak City for Scientific Research and Technology Applications, Alexandria (Egypt); Abd-El-Haleem, Desouky [Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, Mubarak City for Scientific Research and Technology Applications, Alexandria, 21934 New Burgelarab City (Egypt)

    2011-10-15

    Graphical abstract: In this study five bacterial isolates belong to different genera were found to be able to biosynthesize silver nanoparticles. Biosynthesis and spectral characterization are reported here. Highlights: {yields} About 300 bacterial isolates were screened for their ability to produce nanosilvers {yields} Five of them were potential candidates for synthesis of silver nanoparticles {yields} Production of silver nanoparticles was examined using UV-Vis, XRD, SEM and EDS. {yields} The presence of nanoparticles with all five bacterial isolates was confirmed. -- Abstract: This study aimed to develop a green process for biosynthesis of silver nanomaterials by some Egyptian bacterial isolates. This target was achieved by screening an in-house culture collection consists of 300 bacterial isolates for silver nanoparticle formation. Through screening process, it was observed that strains belonging to Escherichia coli (S30, S78), Bacillus megaterium (S52), Acinetobacter sp. (S7) and Stenotrophomonas maltophilia (S54) were potential candidates for synthesis of silver nanoparticles. The extracellular production of silver nanoparticles by positive isolates was investigated by UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results demonstrated that UV-visible spectrum of the aqueous medium containing silver ion showed a peak at 420 nm corresponding to the plasmon absorbance of silver nanoparticles. Scanning electron microscopy micrograph showed formation of silver nanoparticles in the range of 15-50 nm. XRD-spectrum of the silver nanoparticles exhibited 2{theta} values corresponding to the silver nanocrystal that produce in hexagonal and cubic crystal configurations with different plane of orientation. In addition, the signals of the silver atoms were observed by EDS-spectrum analysis that confirms the presence of silver nanoparticles (Ag

  6. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

    International Nuclear Information System (INIS)

    Deng, Shuyan; Chen, Yao; Wang, Daosheng; Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong; Hua, Rimao; Tang, Xinyun; Li, Qing X.

    2015-01-01

    Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation

  7. Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Shuyan; Chen, Yao [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Wang, Daosheng [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Hua, Rimao, E-mail: rimaohua@ahau.edu.cn [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Tang, Xinyun [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Li, Qing X. [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East–West Road, Honolulu, HI 957822 (United States)

    2015-10-30

    Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.

  8. Biofilm formation by Stenotrophomonas maltophilia isolates from device-associated nosocomial infections Formación de biopelículas por aislamientos de Stenotrophomonas maltophilia recuperados de infecciones nosocomiales asociadas al uso de dispositivos médicos

    Directory of Open Access Journals (Sweden)

    B. Passerini De Rossi

    2007-12-01

    Full Text Available Medical devices are often colonized by bacteria which may cause severe infections. The aim of this work was to evaluate biofilm formation by S. maltophilia isolates from device-associated nosocomial infections. The 13 local isolates exhibited different capacities of biofilm formation on hydrophilic and hydrophobic surfaces. All isolates formed strong biofilms in polystyrene microplates, while strong, moderate or weak biofilms were detected in borosilicate (BS or polypropylene (PP tubes. The proficiency of biofilm formation was better evaluated by the level of crystal violet staining expressed relative to the final culture density. The microscopic analysis of biofilms formed on glass coverslips revealed the presence of a matrix of exopolysaccharides and microcolonies typical of biofilm architecture. Isolates with increased adhesion to BS showed larger microcolonies. According to our results, twitching correlated well with attachment to the three abiotic surfaces tested, while swimming only showed a slight correlation with biofilm formation on PP. Poor correlation was observed between cell surface hydrophobicity and biofilm formation. One of the highest biofilm-producing isolates adhered to urethral catheters of different materials, and exhibited an increased resistance to oxidative stress, one of the common stresses encountered by bacteria during the infection process due to the immune response.El objetivo de este trabajo fue evaluar la formación de biopelículas por parte de aislamientos de Stenotrophomonas maltophilia. Los 13 aislamientos locales evaluados mostraron diferente capacidad de formar biopelículas en superficies hidrofílicas e hidrofóbicas. Todos ellos formaron biopelículas fuertes en microplacas de poliestireno (PS, mientras que se observaron biopelículas fuertes, moderadas o débiles en tubos de borosilicato (BS o polipropileno (PP. La medida del cristal violeta unido a la biopelícula expresada en función de la densidad

  9. In Vitro Antibacterial and Antibiofilm Activities of Chlorogenic Acid against Clinical Isolates of Stenotrophomonas maltophilia including the Trimethoprim/Sulfamethoxazole Resistant Strain

    Science.gov (United States)

    Karunanidhi, Arunkumar; Thomas, Renjan; van Belkum, Alex; Neela, Vasanthakumari

    2013-01-01

    The in vitro antibacterial and antibiofilm activity of chlorogenic acid against clinical isolates of Stenotrophomonas maltophilia was investigated through disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill and biofilm assays. A total of 9 clinical S. maltophilia isolates including one isolate resistant to trimethoprim/sulfamethoxazole (TMP/SMX) were tested. The inhibition zone sizes for the isolates ranged from 17 to 29 mm, while the MIC and MBC values ranged from 8 to 16 μg mL−1 and 16 to 32 μg mL−1. Chlorogenic acid appeared to be strongly bactericidal at 4x MIC, with a 2-log reduction in viable bacteria at 10 h. In vitro antibiofilm testing showed a 4-fold reduction in biofilm viability at 4x MIC compared to 1x MIC values (0.085 chlorogenic acid. The data from this study support the notion that the chlorogenic acid has promising in vitro antibacterial and antibiofilm activities against S. maltophilia. PMID:23509719

  10. Current Situation of Antimicrobial Resistance and Genetic Differences in Stenotrophomonas maltophilia Complex Isolates by Multilocus Variable Number of Tandem Repeat Analysis.

    Science.gov (United States)

    Rhee, Ji Young; Song, Jae Hoon; Ko, Kwan Soo

    2016-12-01

    Stenotrophomonas maltophilia is one of several opportunistic pathogens of growing significance. Several studies on the molecular epidemiology of S. maltophilia have shown clinical isolates to be genetically diverse. A total of 121 clinical isolates tentatively identified as S. malophilia from seven tertiary-care hospitals in Korea from 2007 to 2011 were included. Species and groups were identified using partial gyrB gene sequences and antimicrobial susceptibility testing was performed using a broth microdilution method. Multi locus variable number of tandem repeat analysis (MLVA) surveys are used for subtyping. Based on partial gyrB gene sequences, 118 isolates were identified as belonging to the S. maltophilia complex. For all S. maltophilia isolates, the resistance rates to trimethoprime-sulfamethoxazole (TMP/SMX) and levofloxacin were the highest (both, 30.5%). Resistance rate to ceftazidime was 28.0%. 11.0% and 11.9% of 118 S. maltophilia isolates displayed resistance to piperacillin/tazobactam and tigecycline, respectively. Clade 1 and Clade 2 were definitely distinguished from the data of MLVA with amplification of loci. All 118 isolates were classified into several clusters as its identification. Because of high resistance rates to TMP/SMX and levofloxacin, the clinical laboratory department should consider providing the data about other antimicrobial agents and treatment of S. maltophilia infections with a combination of antimicrobials can be considered in the current practice. The MLVA evaluated in this study provides a fast, portable, relatively low cost genotyping method that can be employed in genotypic linkage or transmission networks comparing to analysis of the gyrB gene.

  11. 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.

  12. Characterization of a salt-activated protease with temperature-dependent secretion in Stenotrophomonas maltophilia FF11 isolated from frozen Antarctic krill.

    Science.gov (United States)

    Wang, Qingling; Ji, Fangling; Wang, Jingyun; Jiang, Bo; Li, Lu; An, Lijia; Li, Yachen; Bao, Yongming

    2016-06-01

    Seafood is sometimes wasted due to the growth of psychrotolerant microbes which secrete proteases and break down proteins. Stenotrophomonas maltophilia FF11, isolated from frozen Antarctic krill, grows at a wide range of temperatures and secretes more proteases at low temperatures. According to zymogram analysis, two kinds of proteases were produced from this strain. A major protease was produced largely at 15 °C, but not at 37 °C. The temperature-dependent secreted protease was purified to homogeneity. Its molecular mass was determined at 37.4 kDa and its amino acid sequence was also obtained. This protease is a member of the subtilase group according to the NCBI blast analysis. The enzyme was highly stable at high salt concentration (4 M). Interestingly, its activity increased about 1.6-fold under high salt condition. The enzyme remains active and stable in different organic solvents (50 %, v/v) such as dimethylsulfoxide, dimethyl formamide, dioxane and acetone. These properties may provide potential applications in quality control for sea foods, in protein degradation at high salt concentration, in biocatalysis and biotransformation within non-aqueous media, such as detergent and transesterification.

  13. Isolation of Stenotrophomonas maltophilia from clinical samples: An investigation of patterns motility and production of melanin pigment

    Directory of Open Access Journals (Sweden)

    Rabeeh Izadi Amoli

    2017-09-01

    Conclusions: The highest percentage of bacteria is isolated of oxygen manometer system and dental suction, yet has not been reported from oxygen manometer system. These bacteria have also been associated with patients who have respiratory problems, so it is essential for staffs of hospitals to draw attention to this source of bacteria.

  14. Hexadecane degradation by bacterial strains isolated from ...

    African Journals Online (AJOL)

    A study was undertaken to detect and monitor the degradation of hexadecane by three potential degrading bacteria (Pseudomonas putida, Rhodococcus erythroplolis and Bacillus thermoleovorans) isolated from contaminated soils in Riyadh, Saudi Arabia. The extraction of the bacterial populations from these polluted soils ...

  15. Structure of Stenotrophomonas maltophilia FeoA complexed with zinc: a unique prokaryotic SH3-domain protein that possibly acts as a bacterial ferrous iron-transport activating factor

    International Nuclear Information System (INIS)

    Su, Yi-Che; Chin, Ko-Hsin; Hung, Hui-Chih; Shen, Gwan-Han; Wang, Andrew H.-J.; Chou, Shan-Ho

    2010-01-01

    The crystal structure of FeoA from Stenotrophomonas maltophilia has been determined to a resolution of 1.7 Å using an Se single-wavelength anomalous dispersion (Se-SAD) approach and revealed a unique dimer cross-linked by two zinc ions and six chloride ions. Iron is vital to the majority of prokaryotes, with ferrous iron believed to be the preferred form for iron uptake owing to its much better solubility. The major route for bacterial ferrous iron uptake is found to be via an Feo (ferrous iron-transport) system comprising the three proteins FeoA, FeoB and FeoC. Although the structure and function of FeoB have received much attention recently, the roles played by FeoA and FeoC have been little investigated to date. Here, the tertiary structure of FeoA from Stenotrophomonas maltophilia (Sm), a vital opportunistic pathogen in immunodepressed hosts, is reported. The crystal structure of SmFeoA has been determined to a resolution of 1.7 Å using an Se single-wavelength anomalous dispersion (Se-SAD) approach. Although SmFeoA bears low sequence identity to eukaryotic proteins, its structure is found to adopt a eukaryotic SH3-domain-like fold. It also bears weak similarity to the C-terminal SH3 domain of bacterial DtxR (diphtheria toxin regulator), with some unique characteristics. Intriguingly, SmFeoA is found to adopt a unique dimer cross-linked by two zinc ions and six anions (chloride ions). Since FeoB has been found to contain a G-protein-like domain with low GTPase activity, FeoA may interact with FeoB through the SH3–G-protein domain interaction to act as a ferrous iron-transport activating factor

  16. CHROMagar COL-APSE: a selective bacterial culture medium for the isolation and differentiation of colistin-resistant Gram-negative pathogens

    DEFF Research Database (Denmark)

    Abdul Momin, Muhd Haziq F; Bean, David C; Hendriksen, Rene S.

    2017-01-01

    Purpose. A selective chromogenic culture medium for the laboratory isolation and differentiation of colistin resistant Acinetobacter, Pseudomonas, Stenotrophomonas and Enterobacteriaceae spp. (CHROMagar COL-APSE) was developed, evaluated and compared to an existing selective bacterial culture...... for the growth of COL-resistant bacterial pathogens. Due to the low limit of detection (101 c.f.u.), it may be useful as a primary isolation medium in the surveillance and recovery of COL-resistant bacteria from complex human, veterinary and environmental samples, especially those with plasmid-mediated MCR-1...... medium (SuperPolymyxin). Methodology. The medium was challenged with 84 isolates, including polymyxin B (POL B)-susceptible and -resistant type strains and colistin (COL)-resistant organisms recovered from human and animal samples. Susceptibility to COL and POL B was determined by agar dilution and broth...

  17. Increasing Incidence of Multidrug Resistance Among Cystic Fibrosis Respiratory Bacterial Isolates.

    Science.gov (United States)

    Rutter, W Cliff; Burgess, Donna R; Burgess, David S

    2017-01-01

    Pseudomonas aeruginosa and Staphylococcus aureus are common pathogens in cystic fibrosis (CF) patients with increasing multidrug resistance (MDR). This study characterized antimicrobial susceptibility trends among organisms isolated from the respiratory tract of CF patients. Microbiological culture and sensitivity results for all CF patients were collected from January 2010 through December 2014. Minimum inhibitory concentrations were obtained using Phoenix ® and Etest ® methods. Clinical and Laboratory Standards Institute guidelines were used to remove duplicate isolates and develop antimicrobial susceptibility reports. MDR was defined as resistance to one agent in three or more antibiotic classes or oxacillin resistance in S. aureus. Overall, 542 bacterial isolates from 376 cultures were analyzed for trends. P. aeruginosa (41%), S. aureus (40%), and Stenotrophomonas maltophilia (8%) were the most commonly isolated organisms. Multidrug-resistant organism isolation increased from 39% to 49% (r = 0.76, p = 0.13), while representing 47.6% of all isolates. Multidrug-resistant P. aeruginosa incidence increased each year from 26% to 43% (r = 0.89, p = 0.046), while P. aeruginosa isolation decreased from 47% to 38% over the study period (r = -0.93, p = 0.02). MRSA accounted for 62.6% of all S. aureus isolated, while overall multidrug-resistant S. aureus incidence was 73.1% in all cultures. MDR among common pathogens in CF continues to increase. Empiric therapy for CF exacerbations should be targeted to previous antimicrobial susceptibility, and P. aeruginosa and S. aureus should be empirically covered.

  18. Identification of a Novel 6′-N-Aminoglycoside Acetyltransferase, AAC(6′)-Iak, from a Multidrug-Resistant Clinical Isolate of Stenotrophomonas maltophilia

    Science.gov (United States)

    Tada, Tatsuya; Miyoshi-Akiyama, Tohru; Dahal, Rajan K.; Mishra, Shyam K.; Shimada, Kayo; Ohara, Hiroshi; Pokhrel, Bharat M.

    2014-01-01

    Stenotrophomonas maltophilia IOMTU250 has a novel 6′-N-aminoglycoside acetyltransferase-encoding gene, aac(6′)-Iak. The encoded protein, AAC(6′)-Iak, consists of 153 amino acids and has 86.3% identity to AAC(6′)-Iz. Escherichia coli transformed with a plasmid containing aac(6′)-Iak exhibited decreased susceptibility to arbekacin, dibekacin, neomycin, netilmicin, sisomicin, and tobramycin. Thin-layer chromatography showed that AAC(6′)-Iak acetylated amikacin, arbekacin, dibekacin, isepamicin, kanamycin, neomycin, netilmicin, sisomicin, and tobramycin but not apramycin, gentamicin, or lividomycin. PMID:25092711

  19. Identification of a novel 6'-N-aminoglycoside acetyltransferase, AAC(6')-Iak, from a multidrug-resistant clinical isolate of Stenotrophomonas maltophilia.

    Science.gov (United States)

    Tada, Tatsuya; Miyoshi-Akiyama, Tohru; Dahal, Rajan K; Mishra, Shyam K; Shimada, Kayo; Ohara, Hiroshi; Kirikae, Teruo; Pokhrel, Bharat M

    2014-10-01

    Stenotrophomonas maltophilia IOMTU250 has a novel 6'-N-aminoglycoside acetyltransferase-encoding gene, aac(6')-Iak. The encoded protein, AAC(6')-Iak, consists of 153 amino acids and has 86.3% identity to AAC(6')-Iz. Escherichia coli transformed with a plasmid containing aac(6')-Iak exhibited decreased susceptibility to arbekacin, dibekacin, neomycin, netilmicin, sisomicin, and tobramycin. Thin-layer chromatography showed that AAC(6')-Iak acetylated amikacin, arbekacin, dibekacin, isepamicin, kanamycin, neomycin, netilmicin, sisomicin, and tobramycin but not apramycin, gentamicin, or lividomycin. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  20. Analysis of sequence variation among smeDEF multi drug efflux pump genes and flanking DNA from defined 16S rRNA subgroups of clinical Stenotrophomonas maltophilia isolates.

    Science.gov (United States)

    Gould, Virginia C; Okazaki, Aki; Howe, Robin A; Avison, Matthew B

    2004-08-01

    To determine the level of variation in the smeDEF efflux pump and smeT transcriptional regulator genes among three defined 16S rRNA sequence subgroups of clinical Stenotrophomonas maltophilia isolates. smeDEF sequencing used a PCR genome walking approach. Determination of the sequence surrounding smeDEF used a flanking primer PCR method and specific primers anchored in smeD or smeF together with random primers. smeDEF is chromosomal and located in the same position in the chromosome in all three subgroups of isolates. Flanking smeD is a gene, smeT, encoding a putative transcriptional repressor for smeDEF. Variation at these loci among the isolates is considerably lower (up to 10%) than at intrinsic beta-lactamase loci (up to 30%) in the same isolates, implying greater functional constraint. The smeD-smeT intergenic region contains a highly conserved section, which maps with previously predicted promoter/operator regions, and a hypervariable untranslated region, which can be used to subgroup clinical isolates. These data provide further evidence that it is possible to group clinical isolates of the inherently variable species, S. maltophilia, based on genotypic properties. Isolate D457, in which most work concerning smeDEF expression has been performed, does not fall into S. maltophilia subgroup A, which is the most typical.

  1. Biodegradation of phenol by a newly isolated marine bacterial strain ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-26

    peptone agar plates with. 1500 mg/L phenol. ... biodegradation of the strain was up to 92.0% under the optimum conditions even when the phenol ... Growth of marine bacterial isolates in various concentration of phenol. Isolate.

  2. Calcite biomineralization by bacterial isolates from the recently discovered pristine karstic herrenberg cave.

    Science.gov (United States)

    Rusznyák, Anna; Akob, Denise M; Nietzsche, Sándor; Eusterhues, Karin; Totsche, Kai Uwe; Neu, Thomas R; Frosch, Torsten; Popp, Jürgen; Keiner, Robert; Geletneky, Jörn; Katzschmann, Lutz; Schulze, Ernst-Detlef; Küsel, Kirsten

    2012-02-01

    Karstic caves represent one of the most important subterranean carbon storages on Earth and provide windows into the subsurface. The recent discovery of the Herrenberg Cave, Germany, gave us the opportunity to investigate the diversity and potential role of bacteria in carbonate mineral formation. Calcite was the only mineral observed by Raman spectroscopy to precipitate as stalactites from seepage water. Bacterial cells were found on the surface and interior of stalactites by confocal laser scanning microscopy. Proteobacteria dominated the microbial communities inhabiting stalactites, representing more than 70% of total 16S rRNA gene clones. Proteobacteria formed 22 to 34% of the detected communities in fluvial sediments, and a large fraction of these bacteria were also metabolically active. A total of 9 isolates, belonging to the genera Arthrobacter, Flavobacterium, Pseudomonas, Rhodococcus, Serratia, and Stenotrophomonas, grew on alkaline carbonate-precipitating medium. Two cultures with the most intense precipitate formation, Arthrobacter sulfonivorans and Rhodococcus globerulus, grew as aggregates, produced extracellular polymeric substances (EPS), and formed mixtures of calcite, vaterite, and monohydrocalcite. R. globerulus formed idiomorphous crystals with rhombohedral morphology, whereas A. sulfonivorans formed xenomorphous globular crystals, evidence for taxon-specific crystal morphologies. The results of this study highlighted the importance of combining various techniques in order to understand the geomicrobiology of karstic caves, but further studies are needed to determine whether the mineralogical biosignatures found in nutrient-rich media can also be found in oligotrophic caves.

  3. Denitrification by cystic fibrosis pathogens - Stenotrophomonas maltophilia is dormant in sputum

    DEFF Research Database (Denmark)

    Kolpen, Mette; Kragh, Kasper Nørskov; Bjarnsholt, Thomas

    2015-01-01

    measurements by absorbance changes and colony counting in isolates from 32 CF patients chronically infected with the highly pathogenic bacteria P. aeruginosa, Achromobacter xylosoxidans, Burkholderia multivorans or the less pathogenic bacterium Stenotrophomonas maltophilia. Consumption of NO3(-) and NO2...

  4. characterisation of bacterial isolates from patients wounds and ...

    African Journals Online (AJOL)

    2013-12-12

    Dec 12, 2013 ... resistance pattern of bacterial isolates from the patient's wounds and ward environment. Conclusion: There is a high incidence of antibiotic resistance of bacterial isolates from samples cultured from patients ... friction/ shear force, pressure or as a result of disease, such as leg ulcers or carcinomas (2,3).

  5. Utilization of chitinolytic bacterial isolates to control anthracnose of ...

    African Journals Online (AJOL)

    Colletotrichum spp. are causal agents of anthracnose in many plant species. Biological control of Colletotrichum spp. utilizing bacterial isolates and fungi has been reported. However, chitinolytic bacterial isolate utilization to control anthracnose of cocoa leaf has not seemingly been studied yet. In this study, we used ...

  6. Quinolone Resistance in Bacterial Isolates from Chicken Carcasses ...

    African Journals Online (AJOL)

    Two hundred bacterial isolates including Escherichia coli (95; 47.5%), Salmonella serotypes (78; 38.0%), Klebsiella (17; 8.5%) and Staphylococcus aureus (12; 6.0%) were isolated from chicken carcasses within the six-year period. On the overall, the isolates were resistant to ciprofloxacin (40.5%), enrofloxacin (21.0%), ...

  7. Immersion Refractometry of Isolated Bacterial Cell Walls

    Science.gov (United States)

    Marquis, Robert E.

    1973-01-01

    Immersion-refractometric and light-scattering measurements were adapted to determinations of average refractive indices and physical compactness of isolated bacterial cell walls. The structures were immersed in solutions containing various concentrations of polymer molecules that cannot penetrate into wall pores, and then an estimate was made of the polymer concentration or the refractive index of the polymer solution in which light scattering was reduced to zero. Because each wall preparation was heterogeneous, the refractive index of the medium for zero light scattering had to be estimated by extrapolation. Refractive indices for walls suspended in bovine serum albumin solutions ranged from 1.348 for walls of the rod form of Arthrobacter crystallopoietes to 1.382 for walls of the teichoic acid deficient, 52A5 strain of Staphylococcus aureus. These indices were used to calculate approximate values for solids content per milliliter, and the calculated values agreed closely with those estimated from a knowledge of dextran-impermeable volumes per gram, dry weight, of the walls. When large molecules such as dextrans or serum albumin were used for immersion refractometry, the refractive indices obtained were for entire walls, including both wall polymers and wall water. When smaller molecules that can penetrate wall pores to various extents were used with Micrococcus lysodeikticus walls, the average, apparent refractive index of the structures increased as the molecular size of probing molecules was decreased. It was possible to obtain an estimate of 1.45 to 1.46 for the refractive index of wall polymers, predominantly peptidoglycans in this case, by extrapolating the curve for refractive index versus molecular radius to a value of 0.2 nm, the approximate radius of a water molecule. This relatively low value for polymer refractive index was interpreted as evidence in favor of the amorphous, elastic model of peptidoglycan structure and against the crystalline, rigid

  8. Stenotrophomonas, Mycobacterium, and Streptomyces in home dust and air: associations with moldiness and other home/family characteristics

    Science.gov (United States)

    Abstract Aims: (1) To investigate the dustborne and airborne bacterial concentrations of three emerging moisture-related bacteria: Stenotrophomonas maltophilia, Streptomyces, and Mycobacterium. (2) To study the association between these bacteria concentrations and Environmenta...

  9. CHROMagar COL-APSE: a selective bacterial culture medium for the isolation and differentiation of colistin-resistant Gram-negative pathogens.

    Science.gov (United States)

    Abdul Momin, Muhd Haziq F; Bean, David C; Hendriksen, Rene S; Haenni, Marisa; Phee, Lynette M; Wareham, David W

    2017-11-01

    A selective chromogenic culture medium for the laboratory isolation and differentiation of colistin resistant Acinetobacter, Pseudomonas, Stenotrophomonas and Enterobacteriaceae spp. (CHROMagar COL-APSE) was developed, evaluated and compared to an existing selective bacterial culture medium (SuperPolymyxin). The medium was challenged with 84 isolates, including polymyxin B (POL B)-susceptible and -resistant type strains and colistin (COL)-resistant organisms recovered from human and animal samples. Susceptibility to COL and POL B was determined by agar dilution and broth microtitre dilution. The lower limit for the detection of COL-resistant organisms was also calculated for both CHROMagar COL-APSE and SuperPolymyxin media. The ability to isolate and correctly differentiate COL-resistant organisms within mixed cultures was also assessed and compared using both media. Using CHROMagar COL-APSE, Gram-negative pathogens (n=71) with intrinsic (n=8) or acquired COL (n=63) resistance were recovered with 100 % specificity down to the lower limit of detection of 10 1 colony-forming units (c.f.u.). The growth on SuperPolymyxin was similar, but notably weaker for COL-resistant non-fermentative bacteria (Acinetobacter, Pseudomonas and Stenotrophomonas). CHROMagar COL-APSE was also more sensitive in supporting the growth of Enterobacteriaceae with COL resistance associated with the carriage of mcr-1. CHROMagar COL-APSE is a sensitive and specific medium for the growth of COL-resistant bacterial pathogens. Due to the low limit of detection (10 1  c.f.u.), it may be useful as a primary isolation medium in the surveillance and recovery of COL-resistant bacteria from complex human, veterinary and environmental samples, especially those with plasmid-mediated MCR-1 or novel mechanisms of polymyxin resistance.

  10. Antimicrobial resistance of bacterial strains isolated from orange ...

    African Journals Online (AJOL)

    The organisms encountered include Saccharomyces cerevisiae, Saccharomyces sp, Rhodotorula sp, Bacillus cereus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes and Micrococcus sp. The resistances of thirty bacterial strains isolated from orange juice products to the commonly used ...

  11. (MDR) Bacterial Activity of Endophytic Fungi Isolated from the

    African Journals Online (AJOL)

    MDR) bacterial potential of culturable endophytes from A. corniculatum in Beibu Gulf, China. Methods: The plant parts were collected from healthy-looking A. corniculatum. The endophytes were isolated and identified by colonial morphology and ...

  12. Antibiotics susceptibility patterns of urine bacterial isolates in Zaria ...

    African Journals Online (AJOL)

    Methods: Urine samples collected from students of Faculty of Pharmaceutical Sciences, Ahmadu Bello University and Kaduna State Polytechnic, Zaria, Nigeria, commercial sex workers, and illiterate men and women in Zaria were cultured and bacterial isolates identified using standard microbiological procedures.

  13. Antimicrobial resistance of bacterial isolates from urinary tract ...

    African Journals Online (AJOL)

    Urinary tract infections are common health problems and vary according to geography and regions. A retrospective analysis was conducted to determine the antimicrobial resistance of bacterial isolates from urine at Felege Hiwot Referral Hospital from September 2003 to June 2008. From 529 urine specimens, bacterial ...

  14. In vitro susceptibility of gram-negative bacterial isolates to ...

    African Journals Online (AJOL)

    In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate. Y Mengistu, W Erge, B Bellete. Abstract. Objective: To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Design: Prospective laboratory study. Setting: Tikur Anbessa Hospital, Addis Ababa, ...

  15. Clinical bacterial isolates from hospital environment as agents of ...

    African Journals Online (AJOL)

    The relationship between bacteria isolated from the hospital environment and those from wounds of operated patients was investigated to determine the causal agents of surgical site nosocomial infections. The study was carried out on bacterial species isolated from the theatre, surgical ward and patients' surgical wounds ...

  16. Bacterial Isolates Associated with Pelvic Inflammatory Disease ...

    African Journals Online (AJOL)

    This situation is not in any way different here in Nigeria and more so in the Federal Capital Territory, Abuja where this research was conducted, there had never been any published report so far on PID. It therefore became pertinent that such studies be carried out to evaluate the bacterial organisms which may be associated ...

  17. AEROBIC BACTERIAL ISOLATES FROM INFECTED WOUNDS

    African Journals Online (AJOL)

    boaz

    Nurs. Times. 1985; 81:16-19. 5. Calvin M. Cutaneous wound repair. Wounds. 1998; 10(1): 12-32. 6. Brook I. Aerobic and anaerobic microbiology of necrotizing fasciitis in children. PediatrDermatol. 1996; 13:281-284. 7. Madsen SM, Westh H, Danielson L,. Rosadahi VT Bacterial colonization and healing of venous leg ulcers.

  18. Genome sequencing and annotation of Stenotrophomonas sp. SAM8

    Directory of Open Access Journals (Sweden)

    Samy Selim

    2015-12-01

    Full Text Available We report draft genome sequence of Stenotrophomonas sp. strain SAM8, isolated from environmental water. The draft genome size is 3,665,538 bp with a G + C content of 67.2% and contains 6 rRNA sequence (single copies of 5S, 16S & 23S rRNA. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. LDAV00000000.

  19. Conjunctival sac bacterial flora isolated prior to cataract surgery

    Directory of Open Access Journals (Sweden)

    Suto C

    2012-01-01

    Full Text Available Chikako Suto1,2, Masahiro Morinaga1,2, Tomoko Yagi1,2, Chieko Tsuji3, Hiroshi Toshida41Department of Ophthalmology, Saiseikai Kurihashi Hospital, Saitama; 2Department of Ophthalmology, Tokyo Women's Medical University, Tokyo; 3Department of Clinical Laboratory, Saiseikai Kurihashi Hospital, Saitama; 4Department of Ophthalmology, Juntendo University Shizuoka Hospital, Izunokuni, Shizuoka, JapanObjective: To determine the trends of conjunctival sac bacterial flora isolated from patients prior to cataract surgery.Subjects and methods: The study comprised 579 patients (579 eyes who underwent cataract surgery. Specimens were collected by lightly rubbing the inferior palpebral conjunctival sac with a sterile cotton swab 2 weeks before surgery, and then cultured for isolation of bacteria and antimicrobial sensitivity testing. The bacterial isolates and percentage of drug-resistant isolates were compared among age groups and according to whether or not patients had diabetes mellitus, hyperlipidemia, dialysis therapy, oral steroid use, dry eye syndrome, or allergic conjunctivitis.Results: The bacterial isolation rate was 39.2%. There were 191 strains of Gram-positive cocci, accounting for the majority of all isolates (67.0%, among which methicillin-sensitive coagulase-negative staphylococci was the most frequent (127 strains, 44.5%, followed by methicillin-resistant coagulase-negative staphylococci (37 strains, 12.7%. All 76 Gram-positive bacillary isolates (26.7% were from the genus Corynebacterium. Among the 16 Gram-negative bacillary isolates (5.9%, the most frequent was Escherichia coli (1.0%. The bacterial isolation rate was higher in patients >60 years old, and was lower in patients with dry eye syndrome, patients under topical treatment for other ocular disorders, and patients with hyperlipidemia. There was no significant difference in bacterial isolation rate with respect to the presence/absence of diabetes mellitus, steroid therapy, dialysis, or

  20. Chitinolytic bactery activity isolated from the mud fields

    Directory of Open Access Journals (Sweden)

    Nuniek Herdyastuti

    2012-01-01

    Full Text Available A chitinolytic microorganism had been isolated from mud fields in Ketintang Surabaya area by using a minimal media containing 0.4% colloidal chitin. Activity assay is based on released N-acetyl-glucosamine which reacted with 3,5 dinitrosalicyclic acid. Mud fields produce 63 bacterial isolates with chitinase activity (TNH1 – TNH63 isolates. The highest activity was shown by TNH11 isolate with specific activity 1.27 U/mg. TNH11 isolates was Gram negative, rod-cocoid cell, has a colony of yellow, round shape, convex elevation, flat margin and the colony diameter 3–5 mm.

  1. Isolation and characterization of a bacterial celluloseproducing ...

    African Journals Online (AJOL)

    year ripened persimmon vinegar, which belonged to the family of Acetobacteracea based on its morphological and physiological characteristics. The phylogenetic position of the isolated strain was most closely related to Gluconacetobacter ...

  2. Antibiogram of bacterial species isolated from canine pyometra

    OpenAIRE

    Madhu Swamy; Varun Bassessar; Yamini Verma

    2013-01-01

    Aim: The aim of the present work was to ascertain the bacterial flora causing pyometra in female dogs and their antibiotic sensitivity. Materials and Methods: A study was conducted to determine the antibiogram of bacterial species isolated from 20 female dogs diagnosed with pyometra. The vaginal discharge was collected by sterile swab and streaked smoothly over Mueller Hinton medium and sensitivity towards antibiotics was determined by measuring the zone of inhibition using a Hi-media scale. ...

  3. Antibiogram of bacterial species isolated from canine pyometra

    Directory of Open Access Journals (Sweden)

    Madhu Swamy

    2013-06-01

    Full Text Available Aim: The aim of the present work was to ascertain the bacterial flora causing pyometra in female dogs and their antibiotic sensitivity. Materials and Methods: A study was conducted to determine the antibiogram of bacterial species isolated from 20 female dogs diagnosed with pyometra. The vaginal discharge was collected by sterile swab and streaked smoothly over Mueller Hinton medium and sensitivity towards antibiotics was determined by measuring the zone of inhibition using a Hi-media scale. Results: The antobiogram showed that Gentamicin was the most sensitive (85% antibiotic followed by Enrofloxacin, Ciprofloxacin and Amoxicillin (65%, 65% and 55%, respectively. The isolates were most resistant to Oxytetracycline (85% followed by Tetracycline, Ampicillin, Chloramphenicol, Cloxacillin and Erythromycin (80%, 80%, 75%, 70% and 70%, respectively. Conclusion: Gentamicin was found to be most effective antibiotic against the bacterial species isolated from canine pyometra. [Vet World 2013; 6(8.000: 546-549

  4. ISOLATION OF 2-METHOXYETHANOL DEGRADING BACTERIAL ...

    African Journals Online (AJOL)

    Morphological, physiological, biochemical and molecular characterization of the isolate showed that the strain, designated VB is of the genus Pseudomonas. 16S rRNA sequence analysis showed that the organism is related to Pseudomonas putida at 99.9% and Pseudomonas plecoglossicida at 99.8% similarity level.

  5. Characterization of biocontrol bacterial strains isolated from a suppressiveness-induced soil after amendment with composted almond shells.

    Science.gov (United States)

    Vida, Carmen; Cazorla, Francisco M; de Vicente, Antonio

    The improvement in soil quality of avocado crops through organic amendments with composted almond shells has a positive effect on crop yield and plant health, and enhances soil suppressiveness against the phytopathogenic fungus Rosellinia necatrix. In previous studies, induced soil suppressiveness against this pathogen was related to stimulation of Gammaproteobacteria, especially some members of Pseudomonas spp. with biocontrol-related activities. In this work, we isolated bacteria from this suppressiveness-induced amended soil using a selective medium for Pseudomonas-like microorganisms. We characterized the obtained bacterial collection to aid in identification, including metabolic profiles, antagonistic responses, hybridization to biosynthetic genes of antifungal compounds, production of lytic exoenzymatic activities and plant growth-promotion-related traits, and sequenced and compared amplified 16S rDNA genes from representative bacteria. The final selection of representative strains mainly belonged to the genus Pseudomonas, but also included the genera Serratia and Stenotrophomonas. Their biocontrol-related activities were assayed using the experimental avocado model, and results showed that all selected strains protected the avocado roots against R. necatrix. This work confirmed the biocontrol activity of these Gammaproteobacteria-related members against R. necatrix following specific stimulation in a suppressiveness-induced soil after a composted almond shell application. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  6. Isolation And Characterization Of The Bacterial Flora Of Soy Milk ...

    African Journals Online (AJOL)

    A total of five bacterial isolates designated A1, A2, A3, A4 and A5 were obtained from twelve locally produced soy milk samples purchased from different locations in Nsukka town. The soy milk samples comprised seven unrefrigerated and five refrigerated samples. All samples were 24h-old according to information ...

  7. Biodegradation of orange G by a novel isolated bacterial strain ...

    African Journals Online (AJOL)

    This research article deals with biodegradation of azo dyes by a newly isolated bacterial strain from soil. Azo dyes are recalcitrant to the conventional modes of treatment due to their complex structure. This article reports decolorization of azo dye by, Gram positive, endospore forming and azo reducing, Bacillus megaterium ...

  8. Profiles of antibiotic susceptibilities of bacterial isolates and physico ...

    African Journals Online (AJOL)

    The Venda region of South Africa is predominantly rural and residents rely on untreated water sources for daily water needs. The physico-chemical quality of these water sources including antibiotic susceptibilities of enteric bacterial isolates which would guide clinicians in the empiric management of diarrhoea have ...

  9. Drug sensitivity patterns of bacterial isolates from septic post ...

    African Journals Online (AJOL)

    Drug sensitivity patterns of bacterial isolates from septic post-operative wounds in a regional referral hospital in Uganda. ... Advances in control of infections have not completely eradicated this problem because of development of drug resistance.Antimicrobial resistance can increase complications and costs associated with ...

  10. Investigation of In vitro Mineral Forming Bacterial Isolates from ...

    African Journals Online (AJOL)

    Aim: Although it is known that bacterial mechanisms are involved in dental calculus formation, which is a predisposing factor in periodontal diseases, there have been few studies of such associations, and therefore, information available is limited. The purpose of this study was to isolate and identify aerobic bacteria ...

  11. Antibiotic Sensitivity Pattern of Bacterial Isolates from the Intensive ...

    African Journals Online (AJOL)

    Antibiotic Sensitivity Pattern of Bacterial Isolates from the Intensive Care Unit of a Tertiary Care Hospital in India. ... Tropical Journal of Pharmaceutical Research ... Methods: Retrospective analysis of the indoor case papers of ICUs from January 2010 to 31st March 2011 was carried out at Department of Pharmacology, Govt.

  12. Multiple antimicrobial resistance in bacterial isolates from clinical ...

    African Journals Online (AJOL)

    A total of 545 clinical specimens (pus, blood, urine, and stool) and environmental specimens (air sample, saline solution, nasal swabs etc) were cultured for isolation and identification of aerobic bacteria and antimicrobial susceptibility testing. Out of these, 356(65%) specimens yielded one or more bacterial strains. Frequent ...

  13. Putative radioresistant bacterial isolate from sewage water

    International Nuclear Information System (INIS)

    Ang, April; Chua, Patricia; Perez, Kristine; Rey, April; Rivor Kristel; San Pablo, Czarina; Santos, Ernestine

    2001-01-01

    Sewage water was collected from a stagnant body of water in Balara, Quezon City. approximately 150 ml was aseptically transferred into eight Erlenmeyer flasks. Seven flasks were then subjected to different doses of radiation at the 60 Co irradiation facility, PNRI (Philippine Nuclear Research Institute) which are as follows: 0.01 kGy, 0.1 kGy, 0.5 kGy, 1 kGy, 5 kGy, 10 kGy, and 15 kGy. The remaining flask was used as the control. After irradiation, all the different treatments were subjected to colony count at the culture collection laboratory, NSRI. Results showed that the colonies from sewage water treatments irradiated at 0.01 kGy (treatment A), 0.10 kGy (treatment B), and 0.50 kGy (treatment C) exhibited a decreasing trend with colony counts 4.60 x 10 3 CFU/ml, and 1.30 x 10 3 CFU/ml, and 26 CFU/ml, respectively. Contrastingly, at 1 kGy (treatment D), high colony count of 2.95 x 10 3 CFU/ml was observed which is even higher compared to the control (1.02 x 10 3 CFU/ml). Treatment E that was irradiated at 5 kGy manifested low survival rate (25 CFU/ml) indicating the presence of few putative intermediate radioresistant bacteria. Radiation dose treatments higher than 5 kGy (i.e., 10 kGy and 15 kGy) exhibited no bacterial survival. (Author)

  14. Etiologic significance of bacterial isolates from rams with palpable epididymitis.

    Science.gov (United States)

    Lozano, E A

    1986-05-01

    Identified and partly identified bacterial isolates were obtained from 48 rams of various breeds that had unilateral or bilateral epididymitis. Most of the animals were approximately 1 year of age; a few were older. Brucella ovis, Actinobacillus spp, Corynebacterium spp, Haemophilus spp, Acinetobacter spp, Escherichia coli, Moraxella spp, Staphylococcus spp, Pasteurella spp, Streptococcus spp, and Chlamydia psittaci were isolated. A vaccine strain of B ovis, isolated species of bacteria, and mixtures of isolates of tissue homogenates containing all isolates except B ovis and C psittaci were inoculated via the mucous membranes of the eyes, nares, and prepuce. Palpable epididymitis was not produced by the inoculations. The vaccine strain of B ovis induced complement-fixation reaction in 11 of 20 rams.

  15. High prevalence of biofilm synergy among bacterial soil isolates in cocultures indicates bacterial interspecific cooperation

    DEFF Research Database (Denmark)

    Ren, Dawei; Madsen, Jonas Stenløkke; Sørensen, Søren Johannes

    2015-01-01

    of single-species biofilms, indicating that all the individual strains benefit from inclusion in the multispecies community. Our results show a high prevalence of synergy in biofilm formation in multispecies consortia isolated from a natural bacterial habitat and suggest that interspecific cooperation...

  16. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

    Directory of Open Access Journals (Sweden)

    S. Marasini

    2016-01-01

    Full Text Available Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%, followed by Pseudomonas (21.3%. Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p≤0.05. Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%, cefuroxime (33.3%, and chloramphenicol (94.7% showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51% and ciprofloxacin (98.8% showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres.

  17. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland.

    Science.gov (United States)

    Marasini, S; Swift, S; Dean, S J; Ormonde, S E; Craig, J P

    2016-01-01

    Background. The bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. Objectives. To identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in Auckland, New Zealand, and to investigate in vitro sensitivity to antibiotics. Methods. Hospital admissions for culture-proven bacterial keratitis between January 2013 and December 2014 were identified. Laboratory records of 89 culture positive cases were retrospectively reviewed and antibiotic sensitivity patterns compared with previous studies from other NZ centres. Results. From 126 positive cultures, 35 species were identified. Staphylococcus was identified to be the most common isolate (38.2%), followed by Pseudomonas (21.3%). Over the last decade, infection due to Pseudomonas species, in the same setting, has increased (p ≤ 0.05). Aminoglycosides, cefazolin, ceftazidime, erythromycin, tetracycline, and doxycycline were 100% effective against tested isolates in vitro. Amoxicillin (41.6%), cefuroxime (33.3%), and chloramphenicol (94.7%) showed reduced efficacy against Gram-negative bacteria, whereas penicillin (51%) and ciprofloxacin (98.8%) showed reduced efficacy against Gram-positive bacteria. Conclusions. Despite a shift in the spectrum of bacterial keratitis isolates, antibiotic sensitivity patterns have generally remained stable and show comparability to results within the last decade from NZ centres.

  18. Identification of leptospiral isolates by bacterial restriction endonuclease analysis (Brenda

    Directory of Open Access Journals (Sweden)

    Venkatesha M

    2001-01-01

    Full Text Available DNA samples from 19 reference serovars belonging to 19 different serogroups of Leptospira interrogans and two serovars belonging to Leptospira biflexa were examined by bacterial restriction endonuclease analysis using EcoR I and Hae III enzymes. All the serovars gave unique restriction patterns that differed from each other. DNA from 10 local isolates digested with these enzymes produced patterns which on comparison with the standard patterns produced by reference strains could be identified to serovar level.

  19. Isolation, Characterization and Identification of Environmental Bacterial Isolates with Screening for Antagonism Against Three Bacterial Targets

    Science.gov (United States)

    2017-04-01

    making the broad-spectrum antimicrobial ineffective. When this occurs, the current strategy is to replace an ineffective antimicrobial agent with...Shlae. “Fix the Antibiotic Pipeline ”. Nature 472:32. (2011) Cotter, P.A., C. Hin, and R.P. Ross. “Bacteriocin Developing Innate Immunity for Food...and resistance. Clin. Microbiol. Rev. 12:147—179. (1999) Silver, S. “Bacterial silver resistance: molecular biology and uses and misuses of silver

  20. Molecular cloning of cellulase genes from indigenous bacterial isolates

    International Nuclear Information System (INIS)

    Jong Bor Chyan; Pauline Liew Woan Ying; Mat Rasol Awang

    2006-01-01

    Indigenous cellulolytic bacterial isolates having high activities in degrading carboxymethyl cellulose (CMC) were isolated from local environments. Identification of these isolates were performed by molecular techniques. By using polymerase chain reaction (PCR) techniques, PCR products encoding cellulase gene were amplified from the total genomic DNAs. Purified PCR product was successfully cloned and expressed in Escherichia coli host system. The complete nucleotide sequences of the cellulase genes determined. The analysis of amino acid sequences deduced from the genes indicated that the cloned DNA fragments show high homology to those of endoglucanase genes of family GH5. All cloned genes consist of an N-terminal signal peptide, a catalytic domain of family 5 glycosyl hydrolase and a cellulose-binding domain of family III. (Author)

  1. Frequency of isolation and antibiotic resistance patterns of bacterial isolates from wound infections

    Directory of Open Access Journals (Sweden)

    Stojanović-Radić, Z.

    2016-12-01

    Full Text Available Six hundred and thirteen bacterial strains were isolated from wound swabs and the isolates were identified on the basis of growth on differential and selective media. In order to test the sensitivity of isolated strains to different antibiotics, the disc diffusion method, according to EUCAST protocol v 5.0 was used. The most common species isolated from wound swabs was Staphylococcus epidermidis (18.4%, followed by Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis (16.8%, 12.7% and 10.4%, respectively. The maximum resistance of Gram-positive cocci was observed to penicillin and the lowest to linezolid. Gram-negative bacteria showed the highest resistance to tetracyclines, while the same strains demonstrated the highest sensitivity to polypeptide antibiotics. Comparison of the resistance patterns of Gramnegative and Gram-positive bacterial strains showed significant difference in the tetracycline efficiency.

  2. Stenotrophomonas maltophilia: a new potential biocontrol agent of Ralstonia solanacearum, causal agent of potato brown rot

    NARCIS (Netherlands)

    Messiha, N.A.S.; Diepeningen, van A.D.; Farag, N.S.; Abdallah, S.A.; Janse, J.D.; Bruggen, van A.H.C.

    2007-01-01

    Stenotrophomonas maltophilia was isolated from the rhizosphere of eggplant in the Nile Delta of Egypt, and its antagonistic potential against Ralstonia solanacearum race 3 biovar 2, the causal agent of potato brown rot, was in vitro evaluated on KB agar medium and in vivo on potato plants. In vitro,

  3. Isolation and in vitro evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections.

    Science.gov (United States)

    Pallavali, Roja Rani; Degati, Vijaya Lakshmi; Lomada, Dakshayani; Reddy, Madhava C; Durbaka, Vijaya Raghava Prasad

    2017-01-01

    Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages in vitro as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS), Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested in vitro for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had Pseudomonas aeruginosa as the predominant bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100%) were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. In vitro analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence, our results suggest

  4. Isolation and in vitro evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections.

    Directory of Open Access Journals (Sweden)

    Roja Rani Pallavali

    Full Text Available Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages in vitro as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS, Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested in vitro for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had Pseudomonas aeruginosa as the predominant bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100% were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. In vitro analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence

  5. Isolation of cell-free bacterial inclusion bodies.

    Science.gov (United States)

    Rodríguez-Carmona, Escarlata; Cano-Garrido, Olivia; Seras-Franzoso, Joaquin; Villaverde, Antonio; García-Fruitós, Elena

    2010-09-17

    Bacterial inclusion bodies are submicron protein clusters usually found in recombinant bacteria that have been traditionally considered as undesirable products from protein production processes. However, being fully biocompatible, they have been recently characterized as nanoparticulate inert materials useful as scaffolds for tissue engineering, with potentially wider applicability in biomedicine and material sciences. Current protocols for inclusion body isolation from Escherichia coli usually offer between 95 to 99% of protein recovery, what in practical terms, might imply extensive bacterial cell contamination, not compatible with the use of inclusion bodies in biological interfaces. Using an appropriate combination of chemical and mechanical cell disruption methods we have established a convenient procedure for the recovery of bacterial inclusion bodies with undetectable levels of viable cell contamination, below 10⁻¹ cfu/ml, keeping the particulate organization of these aggregates regarding size and protein folding features. The application of the developed protocol allows obtaining bacterial free inclusion bodies suitable for use in mammalian cell cultures and other biological interfaces.

  6. Antibiotic resistance pattern of bacterial isolates in neonatal care unit

    Directory of Open Access Journals (Sweden)

    S Shrestha

    2010-12-01

    Full Text Available INTRODUCTION: Bacterial infections account for a huge proportion of neonatal deaths worldwide. The problem of antibiotic resistance among common bacterial pathogens mainly the gram negative bacteria is emerging globally which is of more serious concern in developing countries like Nepal. METHODS: A one year retrospective hospital based study was carried out to analyze the results of neonatal blood, cerebrospinal fluid, urine, stool and surface cultures and to look into the sensitivity pattern of the commonly used antibiotics. RESULTS: The positive yield of blood, urine, eye swab and CSF cultures were 19.56%, 38.5%, 60% and 0.36% respectively. The most common isolates in the blood culture were coagulase negative Staphylococcus, Acinetobacter, Enterobacter and non-haemolytic Streptococcus. A significant percent of the isolates were resistant to the first line antibiotics. Among the gram negative isolates more than 30% are resistant to cefotaxime and more than 50% are resistant to gentamicin. During the one year period we had Nursery outbreaks of methicillin resistant Staphylococcus aureus and Salmonella infections. With the help of environmental cultures we were able to trace the source and intervene appropriately. CONCLUSIONS: Continuous surveillance for antibiotic susceptibility, rational use of antibiotics and the strategy of antibiotic cycling can provide some answers to the emerging problem of antibiotic resistance.

  7. Antibiotic resistance pattern of bacterial isolates in neonatal care unit.

    Science.gov (United States)

    Shrestha, S; Adhikari, N; Rai, B K; Shreepaili, A

    2010-01-01

    Bacterial infections account for a huge proportion of neonatal deaths worldwide. The problem of antibiotic resistance among common bacterial pathogens mainly the gram negative bacteria is emerging globally which is of more serious concern in developing countries like Nepal. A one year retrospective hospital based study was carried out to analyze the results of neonatal blood, cerebrospinal fluid, urine, stool and surface cultures and to look into the sensitivity pattern of the commonly used antibiotics. The positive yield of blood, urine, eye swab and CSF cultures were 19.56%, 38.5%, 60% and 0.36% respectively. The most common isolates in the blood culture were coagulase negative Staphylococcus, Acinetobacter, Enterobacter and non-haemolytic Streptococcus. A significant percent of the isolates were resistant to the first line antibiotics. Among the gram negative isolates more than 30% are resistant to cefotaxime and more than 50% are resistant to gentamicin. During the one year period we had Nursery outbreaks of methicillin resistant Staphylococcus aureus and Salmonella infections. With the help of environmental cultures we were able to trace the source and intervene appropriately. Continuous surveillance for antibiotic susceptibility, rational use of antibiotics and the strategy of antibiotic cycling can provide some answers to the emerging problem of antibiotic resistance.

  8. Biosurfactant production by the crude oil degrading Stenotrophomonas sp. B-2: chemical characterization, biological activities and environmental applications.

    Science.gov (United States)

    Gargouri, Boutheina; Contreras, María Del Mar; Ammar, Sonda; Segura-Carretero, Antonio; Bouaziz, Mohamed

    2017-02-01

    In this work, biosurfactant-producing microorganisms were isolated from hydrocarbon-contaminated water collected from Tunisian oilfield. After enrichment and isolation, different bacterial strains were preliminary studied for their biosurfactant/bioemulsifier properties when using crude oil as the unique carbon source. In particular, the isolate strain B-2, a Gram-negative, rod-shaped bacterium, efficiently emulsified crude oil. The extracellular biosurfactant product from this strain presented an emulsification activity above 70% and a hydrophobicity of 71%. In addition, a diameter of 6 cm was observed in the oil displacement test. The characterization of B-2 strain using 16S rDNA sequencing enables us to find a high degree of similarity with various members of the genus Stenotrophomonas (with a percentage of similarity of 99%). The emulsification activity of Stenotrophomonas biosurfactant B-2 was maintained in a wide range of pH (2 to 6), temperature (4 to 55 °C), and salinity (0 to 50 g L -1 ) conditions. It also enhanced the solubility of phenanthrene in water and could be used in the re-mobilization of hydrocarbon-contaminated environment. In addition, this biosurfactant exhibited antimicrobial and antioxidant properties. Infrared spectroscopy suggested potential lipidic and peptidic moieties, and mass spectrometry-based analyses showed that the biosurfactant contains mainly cyclic peptidic structures belonging to the class of diketopiperazines. Therefore, the B-2 strain is a promising biosurfactant-producing microorganism and its derived biosurfactant presents a wide range of industrial applications.

  9. Potential of Polycyclic Aromatic Hydrocarbon-Degrading Bacterial Isolates to Contribute to Soil Fertility.

    Science.gov (United States)

    Bello-Akinosho, Maryam; Makofane, Rosina; Adeleke, Rasheed; Thantsha, Mapitsi; Pillay, Michael; Chirima, George Johannes

    2016-01-01

    Restoration of polycyclic aromatic hydrocarbon- (PAH-) polluted sites is presently a major challenge in agroforestry. Consequently, microorganisms with PAH-degradation ability and soil fertility improvement attributes are sought after in order to achieve sustainable remediation of polluted sites. This study isolated PAH-degrading bacteria from enriched cultures of spent automobile engine-oil polluted soil. Isolates' partial 16S rRNA genes were sequenced and taxonomically classified. Isolates were further screened for their soil fertility attributes such as phosphate solubilization, atmospheric nitrogen fixation, and indoleacetic acid (IAA) production. A total of 44 isolates were obtained and belong to the genera Acinetobacter , Arthrobacter , Bacillus , Flavobacterium , Microbacterium , Ochrobactrum , Pseudomonas , Pseudoxanthomonas , Rhodococcus , and Stenotrophomonas . Data analysed by principal component analysis showed the Bacillus and Ochrobactrum isolates displayed outstanding IAA production. Generalized linear modelling statistical approaches were applied to evaluate the contribution of the four most represented genera ( Pseudomonas , Acinetobacter , Arthrobacter , and Rhodococcus ) to soil fertility. The Pseudomonas isolates were the most promising in all three soil fertility enhancement traits evaluated and all isolates showed potential for one or more of the attributes evaluated. These findings demonstrate a clear potential of the isolates to participate in restorative bioremediation of polluted soil, which will enhance sustainable agricultural production and environmental protection.

  10. A clinical Acanthamoeba isolate harboring two distinct bacterial endosymbionts.

    Science.gov (United States)

    Müller, Anneliese; Walochnik, Julia; Wagner, Martin; Schmitz-Esser, Stephan

    2016-10-01

    Acanthamoebae feed on bacteria but are also frequent hosts of bacterial symbionts. Here, we describe the stable co-occurrence of two symbionts, one affiliated to the genus Parachlamydia and the other to the candidate genus Paracaedibacter (Alphaproteobacteria), within a clinical isolate of Acanthamoeba hatchetti genotype T4. We performed fluorescence in situ hybridization (FISH) and transmission electron microscopy (TEM) to describe this symbiosis. Our study adds to other reports of simultaneous co-occurrence of two symbionts within one Acanthamoeba cell. Copyright © 2016 Elsevier GmbH. All rights reserved.

  11. Validation of hierarchical cluster analysis for identification of bacterial species using 42 bacterial isolates

    Science.gov (United States)

    Ghebremedhin, Meron; Yesupriya, Shubha; Luka, Janos; Crane, Nicole J.

    2015-03-01

    Recent studies have demonstrated the potential advantages of the use of Raman spectroscopy in the biomedical field due to its rapidity and noninvasive nature. In this study, Raman spectroscopy is applied as a method for differentiating between bacteria isolates for Gram status and Genus species. We created models for identifying 28 bacterial isolates using spectra collected with a 785 nm laser excitation Raman spectroscopic system. In order to investigate the groupings of these samples, partial least squares discriminant analysis (PLSDA) and hierarchical cluster analysis (HCA) was implemented. In addition, cluster analyses of the isolates were performed using various data types consisting of, biochemical tests, gene sequence alignment, high resolution melt (HRM) analysis and antimicrobial susceptibility tests of minimum inhibitory concentration (MIC) and degree of antimicrobial resistance (SIR). In order to evaluate the ability of these models to correctly classify bacterial isolates using solely Raman spectroscopic data, a set of 14 validation samples were tested using the PLSDA models and consequently the HCA models. External cluster evaluation criteria of purity and Rand index were calculated at different taxonomic levels to compare the performance of clustering using Raman spectra as well as the other datasets. Results showed that Raman spectra performed comparably, and in some cases better than, the other data types with Rand index and purity values up to 0.933 and 0.947, respectively. This study clearly demonstrates that the discrimination of bacterial species using Raman spectroscopic data and hierarchical cluster analysis is possible and has the potential to be a powerful point-of-care tool in clinical settings.

  12. Potential of Polycyclic Aromatic Hydrocarbon-Degrading Bacterial Isolates to Contribute to Soil Fertility

    Directory of Open Access Journals (Sweden)

    Maryam Bello-Akinosho

    2016-01-01

    Full Text Available Restoration of polycyclic aromatic hydrocarbon- (PAH- polluted sites is presently a major challenge in agroforestry. Consequently, microorganisms with PAH-degradation ability and soil fertility improvement attributes are sought after in order to achieve sustainable remediation of polluted sites. This study isolated PAH-degrading bacteria from enriched cultures of spent automobile engine-oil polluted soil. Isolates’ partial 16S rRNA genes were sequenced and taxonomically classified. Isolates were further screened for their soil fertility attributes such as phosphate solubilization, atmospheric nitrogen fixation, and indoleacetic acid (IAA production. A total of 44 isolates were obtained and belong to the genera Acinetobacter, Arthrobacter, Bacillus, Flavobacterium, Microbacterium, Ochrobactrum, Pseudomonas, Pseudoxanthomonas, Rhodococcus, and Stenotrophomonas. Data analysed by principal component analysis showed the Bacillus and Ochrobactrum isolates displayed outstanding IAA production. Generalized linear modelling statistical approaches were applied to evaluate the contribution of the four most represented genera (Pseudomonas, Acinetobacter, Arthrobacter, and Rhodococcus to soil fertility. The Pseudomonas isolates were the most promising in all three soil fertility enhancement traits evaluated and all isolates showed potential for one or more of the attributes evaluated. These findings demonstrate a clear potential of the isolates to participate in restorative bioremediation of polluted soil, which will enhance sustainable agricultural production and environmental protection.

  13. Isolation and development of bioluminescent reporter phages for bacterial dysentery.

    Science.gov (United States)

    Schofield, D A; Wray, D J; Molineux, I J

    2015-02-01

    Shigellosis is a significant cause of morbidity and mortality worldwide, most notably amongst children. Moreover, there is a global increase in the occurrence of multidrug-resistant isolates, including the epidemic and pandemic Shigella dysenteriae type 1 strain. We developed a bioluminescent reporter phage assay to facilitate detection and simultaneously determine antibiotic susceptibility. A Shigella flexneri phage (Shfl25875) was isolated from environmental wastewater and characterized by DNA sequencing. Shfl25875 is T4-like, harbors a 169,062-bp genome, and grows on most (28/29) S. flexneri strains and all 12 S. dysenteriae type 1 strains tested. The genes encoding bacterial luciferase were integrated into the Shfl25875 genome to create a "light-tagged" phage capable of transducing a bioluminescent phenotype to infected cells. Shfl25875::luxAB rapidly detects cultured isolates with high sensitivity. Specificity experiments indicate that the reporter does not respond to Shigella boydii, non-type 1 S. dysenteriae strains, and most non-Shigella Enterobacteriaceae. Shfl25875::luxAB generates ampicillin and ciprofloxacin susceptibility profiles that are similar to the standard Clinical and Laboratory Standards Institute (CLSI) growth microdilution method, but in a significantly shorter time. In addition, the reporter phage detects Shigella in mock-infected stool. This new reporter phage shows promise as a tool for the detection of cultured isolates or complex clinical samples.

  14. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

    Directory of Open Access Journals (Sweden)

    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  15. Identification of swine influenza A virus and Stenotrophomonas maltophilia co-infection in Chinese pigs

    Directory of Open Access Journals (Sweden)

    Hou Dongjun

    2012-08-01

    Full Text Available Abstract Background Influenza virus virulence can be exacerbated by bacterial co-infections. Swine influenza virus (SIV infection together with some bacteria is found to enhance pathogenicity. Methods SIV-positive samples suspected of containing bacteria were used for bacterial isolation and identification. Antimicrobial susceptibility testing was performed by disc diffusion methods. To investigate the interaction of SIV and the bacteria in vitro, guinea pigs were used as mammalian hosts to determine the effect on viral susceptibility and transmissibility. Differences in viral titers between groups were compared using Student’s t-test. Results During surveillance for SIV in China from 2006 to 2009, seven isolates (24.14% of 29 influenza A viruses were co-isolated with Stenotrophomonas maltophilia from nasal and tracheal swab samples of pigs. Antimicrobial susceptibility testing showed that the bacteria possessed a high level of resistance towards clinically used antibiotics. To investigate the interaction between these two microorganisms in influencing viral susceptibility and transmission in humans, guinea pigs were used as an infection model. Animals were inoculated with SIV or S. maltophilia alone or co-infected with SIV and S. maltophilia. The results showed that although no transmission among guinea pigs was observed, virus–bacteria co-infections resulted in higher virus titers in nasal washes and trachea and a longer virus shedding period. Conclusions This is the first report of influenza virus co-infection with S. maltophilia in the Chinese swine population. Increased replication of virus by co-infection with multidrug resistant bacteria might increase the infection rate of SIV in humans. The control of S. maltophilia in clinics will contribute to reducing the spread of SIV in pigs and humans.

  16. Antibiotics resistance of Stenotrophomonas maltophilia strains ...

    African Journals Online (AJOL)

    Introduction. Stenotrophomonas maltophilia is a resistant pathogen that can cause bacteremia, endocarditis, respiratory system, central nervous system and urinary tract infections in patients with risk factors like malignancy or neutrope- nia, use of broad-spectrum antibiotics like carbapenem or long-term hospitalization1,2.

  17. Antimicrobial resistance of bacterial enteropathogens isolated from stools in Madagascar.

    Science.gov (United States)

    Randrianirina, Frederique; Ratsima, Elisoa Hariniana; Ramparany, Lova; Randremanana, Rindra; Rakotonirina, Hanitra Clara; Andriamanantena, Tahiry; Rakotomanana, Fanjasoa; Rajatonirina, Soatiana; Richard, Vincent; Talarmin, Antoine

    2014-02-25

    Diarrheal diseases are a major public health problem in developing countries, and are one of the main causes of hospital admissions in Madagascar. The Pasteur Institute of Madagascar undertook a study to determine the prevalence and the pathogenicity of bacterial, viral and protozoal enteropathogens in diarrheal and non-diarrheal stools of children aged less than 5 years in Madagascar. We present here the results of the analysis of antimicrobial susceptibility of the bacteria isolated during this study. The study was conducted in the community setting in 14 districts of Madagascar from October 2008 to May 2009. Conventional methods and PCR were used to identify the bacteria; antimicrobial susceptibility was determined using an agar diffusion method for enterobacteriaceae and MICs were measured by an agar dilution method for Campylobacter sp. In addition to the strains isolated during this study, Salmonella sp and Shigella sp isolated at the Pasteur Institute of Madagascar from 2005 to 2009 were included in the analysis to increase the power of the study. Twenty-nine strains of Salmonella sp, 35 strains of Shigella sp, 195 strains of diarrheagenic E. coli, 203 strains of C. jejuni and 71 strains of C. coli isolated in the community setting were tested for antibiotic resistance. Fifty-five strains of Salmonella sp and 129 strains of Shigella sp isolated from patients referred to the Pasteur Institute of Madagascar were also included in the study. Many E. coli and Shigella isolates (around 80%) but fewer Salmonella isolates were resistant to ampicillin and trimethoprim/sulfamethoxazole. A small proportion of strains of each species were resistant to ciprofloxacin and only 3% of E. coli strains presented a resistance to third generation cephalosporins due to the production of extended-spectrum beta-lactamases. The resistance of Campylobacter sp to ampicillin was the most prevalent, whereas less than 5% of isolates were resistant to each of the other antibiotics. The

  18. Isolation of human spontaneous killer lymphocytes by bacterial adherence.

    Science.gov (United States)

    Kleinman, R; De Boer, K P; Teodorescu, M

    1980-01-01

    Human lymphocyte subpopulations (B, T1, T2, T3, and T4 our denomination) have been identified previously by bacterial adherence and differences between them in mitogen responses and specific cytotoxic activity have been found. In this study another aspect has been investigated in order to find functions associated with these subpopulations, namely the spontaneous killing (SK) ability. Freshly isolated human peripheral blood lymphocytes (PBL) were separated into adherent and non-adherent cells following centrifugation against various bact:rial monolayers. The PBL and the resulting subpopulations of PBL were tested alone or in combination as effector cells in a 4 hr cytotoxicity assay against human lymphoblastoid cel- lines of B or T cell origin. The T3 + T4 cells or T4 cells alone showed a significantly higher SK activity against both B and T target cell lines when compared with unseparated PBL, T1 + T2, or T3 cells alone. Whe Fc portion of IgG, contain the lymphocytes responsible for SK activity and that SK cells can be purified by negative selection using bacterial adherence. PMID:7389207

  19. Isolation of amoebic-bacterial consortia capable of degrading trichloroethylene

    International Nuclear Information System (INIS)

    Tyndall, R.L.; Ironside, K.; Little, C.D.; Katz, S.; Kennedy, J.

    1990-01-01

    Groundwater from a waste disposal site contaminated with chlorinated alkenes was examined for the presence of amoebic-bacterial consortia capable of degrading the suspected carcinogen, trichloroethylene (TCE). Consortia were readily isolated from all of four test wells. They contained free-living amoebae, and heterotrophic and methylotrophic bacteria. Electron microscopic examination showed bacteria localized throughout the amoebic cytoplasm and an abundance of hyphomicrobium, but not Type I methanotrophs. The presence of Type II methanotrophs was indirectly indicated by lipid analysis of one consortium. The consortia have been passaged for over two years on mineral salts media in a methane atmosphere, which would not be expected to maintain the heterotrophs or amoebae separately. The methanotrophic bacteria apparently provided a stable nutrient source, allowing the persistence of the various genera. By use of 14 C-radiotracer techniques, the degradation of TCE by the consortia was observed with 14 C eventuating predominantly in CO 2 and water-soluble products. In a more detailed examination of one consortia, the amoebae and heterotrohic components did not degrade TCE, while a mixed culture of heterotrophs and methanotrophs did degrade TCE, suggesting the latter component was the primary cause for the consortium's ability to degrade TCE. Amoebic-bacterial consortia may play a role in stabilizing and preserving methylotrophic bacteria in hostile environments

  20. Evaluation in Cellulolytic Activity of Stenotrophomonas sp. in Cellulose Nitrogen Free Mineral Medium

    International Nuclear Information System (INIS)

    Honey Thet Paing Htway; San San Yu; Zaw Ko Latt

    2011-12-01

    Three bacterial strains were isolated from rice rhizospheric soil and their nitrogen fixing activity was determined in nitrogen free mineral medium and broth with glucose and cellulose as carbon sources and they produced ammonium concentration (above 3ppm) in G-NFFMM and (2-3ppm) in C-NFMM. Moreover, their cellulolytic activity was determined by DNS mothod and strain H3 having the cellulolytic activity was selected. Then, cellulose, carboxymethyl cellulose, baggasse, pea haulm, corn stem, rice straw were used as substrates and determined its reducing sugar concentration. After detection of the cellulolytic activity, the bacteria produced the highest concentration of reducing sugar on cellulose substrate at 12 day incubation period with the reducing sugar amount of 0.12mg/ml and 0.298mg/ml on CMC substrates. In the study of argicultral wastes as substrates, the selected strain, H3, produced in the reducing sugar concentration with 0.12, 0.116,0.103 and 0.098mg/ml respectively. The selected strain was identified by biochemical characterists and 16s ribosomal DNA analysis and it was Stenotrophomonas sp.

  1. 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.

  2. Denitrification by cystic fibrosis pathogens - Stenotrophomonas maltophilia is dormant in sputum.

    Science.gov (United States)

    Kolpen, Mette; Kragh, Kasper Nørskov; Bjarnsholt, Thomas; Line, Laura; Hansen, Christine Rønne; Dalbøge, Christina Schjellerup; Hansen, Nana; Kühl, Michael; Høiby, Niels; Jensen, Peter Østrup

    2015-01-01

    Chronic Pseudomonas aeruginosa lung infection is the most severe complication for cystic fibrosis (CF) patients. Infected endobronchial mucus of CF patients contains anaerobic zones mainly due to the respiratory burst of polymorphonuclear leukocytes. We have recently demonstrated ongoing denitrification in sputum from patients infected with P. aeruginosa. Therefore we aimed to investigate, whether the pathogenicity of several known CF pathogens is correlated to their ability to perform denitrification. We measured denitrification with N(2)O microsensors in concert with anaerobic growth measurements by absorbance changes and colony counting in isolates from 32 CF patients chronically infected with the highly pathogenic bacteria P. aeruginosa, Achromobacter xylosoxidans, Burkholderia multivorans or the less pathogenic bacterium Stenotrophomonas maltophilia. Consumption of NO(3)(-) and NO(2)(-) was estimated by the Griess Assay. All isolates were assayed during 2 days of incubation in anaerobic LB broth with NO(3)(-) or NO(2)(-). PNA FISH staining of 16S rRNA was used to estimate the amount of ribosomes per bacterial cells and thereby the in situ growth rate of S. maltophilia in sputum. Supplemental NO(3)(-) caused increased production of N(2)O by P. aeruginosa, A. xylosoxidans and B. multivorans and increased growth for all pathogens. Growth was, however, lowest for S. maltophilia. NO(3)(-) was metabolized by all pathogens, but only P. aeruginosa was able to remove NO(2)(-). S. maltophilia had limited growth in sputum as seen by the weak PNA FISH staining. All four pathogens were able to grow anaerobically by NO(3)(-) reduction. Denitrification as demonstrated by N(2)O production was, however, not found in S. maltophilia isolates. The ability to perform denitrification may contribute to the pathogenicity of the infectious isolates since complete denitrification promotes faster anaerobic growth. The inability of S. maltophilia to proliferate by denitrification and

  3. Effect of isolate of ruminal fibrolytic bacterial culture supplementation on fibrolytic bacterial population and survivability of inoculated bacterial strain in lactating Murrah buffaloes

    Directory of Open Access Journals (Sweden)

    Brishketu Kumar

    2013-02-01

    Full Text Available Aim: The present study was conducted to evaluate the effect of bacterial culture supplementation on ruminal fibrolytic bacterial population as well as on survivability of inoculated bacterial strain in lactating Murrah buffaloes kept on high fibre diet. Materials and Methods: Fibrolytic bacterial strains were isolated from rumen liquor of fistulated Murrah buffaloes and live bacterial culture were supplemented orally in treatment group of lactating Murrah buffaloes fed on high fibre diet to see it's effect on ruminal fibrolytic bacterial population as well as to see the effect of survivability of the inoculated bacterial strain at three different time interval in comparison to control group. Results: It has been shown by real time quantification study that supplementation of bacterial culture orally increases the population of major fibre degrading bacteria i.e. Ruminococcus flavefaciens, Ruminococcus albus as well as Fibrobacter succinogenes whereas there was decrease in secondary fibre degrading bacterial population i.e. Butyrivibrio fibrisolvens over the different time periods. However, the inoculated strain of Ruminococcus flavefaciens survived significantly over the period of time, which was shown in stability of increased inoculated bacterial population. Conclusion: The isolates of fibrolytic bacterial strains are found to be useful in increasing the number of major ruminal fibre degrading bacteria in lactating buffaloes and may act as probiotic in large ruminants on fibre-based diets. [Vet World 2013; 6(1.000: 14-17

  4. Orbital abscess bacterial isolates and in vitro antimicrobial susceptibility patterns in dogs and cats.

    Science.gov (United States)

    Wang, Annie L; Ledbetter, Eric C; Kern, Thomas J

    2009-01-01

    To determine bacterial populations, in vitro antimicrobial susceptibility patterns, and sources of microorganisms for dogs and cats with orbital abscess. In total, 34 dogs and 7 cats with orbital abscess participated in the study. Medical records of dogs and cats with a clinical diagnosis of orbital abscess, confirmed by cytologic or histopathologic evaluation of orbital specimens, were reviewed from the years 1990 to 2007. Animal signalment, presumptive source of microorganisms and mechanism of orbital introduction, bacterial isolates, and aerobic bacterial in vitro antimicrobial susceptibility test results were recorded. Percentages of susceptible aerobic bacterial isolates were compared among antimicrobials. Twenty dogs and five cats had positive culture results. The most frequent bacterial genera isolated from dogs were Staphylococcus, Escherichia, Bacteroides, Clostridium and Pasteurella. The most frequent bacterial genera isolated from cats were Pasteurella and Bacteroides. Aerobic bacterial isolates from dogs had the highest percentage of susceptibility to amikacin, ceftiofur, gentamicin, imipenem, ticarcillin and trimethoprim-sulfamethoxazole. Aerobic bacterial isolates from dogs had the lowest percentage of susceptibility to ampicillin, clindamycin, erythromycin and penicillin. Antimicrobial resistance was uncommon among feline aerobic bacterial isolates. The most commonly identified routes of orbital bacteria introduction were extension from adjacent anatomical structures, penetrating exogenous trauma, and foreign bodies. Mixed aerobic and anaerobic bacterial infections of the orbit occur commonly in dogs and cats. On the basis of aerobic and anaerobic bacterial isolates and in vitro susceptibility testing of aerobic bacterial isolates, cephalosporins, extended-spectrum penicillins, potentiated-penicillins and carbapenems are recommended for initial antimicrobial therapy of orbital abscess in dogs and cats.

  5. Antibiotic resistance profile of bacterial isolates from food sold on a ...

    African Journals Online (AJOL)

    The antibiotic resistance profile of bacterial isolates from cooked food samples sold in different eateries on the campus of the University of Ado-Ekiti was investigated. A total of seventy-eight bacterial isolates belonging to six genera were encountered in the following proportion: Escherichia coli (29.5%), Klebsiella spp.

  6. Aflatoxin B1 Degradation by Stenotrophomonas Maltophilia and Other Microbes Selected Using Coumarin Medium

    Directory of Open Access Journals (Sweden)

    Tiangui Niu

    2008-08-01

    Full Text Available Aflatoxin B1 (AFB1 is one of the most harmful mycotoxins in animal production and food industry. A safe, effective and environmentally sound detoxification method is needed for controlling this toxin. In this study, 65 samples were screened from various sources with vast microbial populations using a newly developed medium containing coumarin as the sole carbon source. Twenty five single-colony bacterial isolates showing AFB1 reduction activity in a liquid culture medium were selected from the screen. Isolate 35-3, obtained from tapir feces and identified to be Stenotrophomonas maltophilia, reduced AFB1 by 82.5% after incubation in the liquid medium at 37 °C for 72 h. The culture supernatant of isolate 35-3 was able to degrade AFB1 effectively, whereas the viable cells and cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Activity was reduced to 60.8% and 63.5% at 20 °C and 30 °C, respectively, from 78.7% at 37 °C. The highest degradation rate was 84.8% at pH 8 and the lowest was only 14.3% at pH 4.0. Ions Mg2+ and Cu2+ were activators for AFB1 degradation, howeverï��Œion Zn2+ was a strong inhibitor. Treatments with proteinase K, proteinase K plus SDS and heating significantly reduced or eradicated the degradation activity of the culture supernatant. The results indicated that the degradation of AFB1 by S. maltophilia 35-3 was enzymatic and could have a great potential in industrial applications.

  7. Synthesis of Chitin Oligosaccharides Using Dried Stenotrophomonas maltophilia Cells Containing a Transglycosylation Reaction-Catalyzing β-N-Acetylhexosaminidase as a Whole-Cell Catalyst.

    Science.gov (United States)

    Uehara, Asaki; Takahashi, Narumi; Moriyama, Mei; Hirano, Takako; Hakamata, Wataru; Nishio, Toshiyuki

    2018-02-01

    Bacterial strain NYT501, which we previously isolated from soil, was identified as Stenotrophomonas maltophilia, and it was confirmed that this strain produces an intracellular β-N-acetylhexosaminidase exhibiting transglycosylation activity. Several properties of this enzyme were characterized using a partially purified enzyme preparation. Using N,N'-diacetylchitobiose (GlcNAc) 2 and N,N',N″-triacetylchitotriose (GlcNAc) 3 as substrates and dried cells of this bacterium as a whole-cell catalyst, chitin oligosaccharides of higher degrees of polymerization were synthesized. (GlcNAc) 3 was generated from (GlcNAc) 2 as the major transglycosylation product, and a certain amount of purified sample of the trisaccharide was obtained. By contrast, in the case of the reaction using (GlcNAc) 3 as a substrate, the yield of higher-degree polymerization oligosaccharides was comparatively low.

  8. Bacterial isolates from equine infections in western Canada (1998–2003)

    OpenAIRE

    Clark, Chris; Greenwood, Sarah; Boison, Joe O.; Chirino-Trejo, Manuel; Dowling, Patricia M.

    2008-01-01

    All bacterial samples of equine origin submitted to the diagnostic laboratory at the Western College of Veterinary Medicine from January 1998 to December 2003 from either “in-clinic” or Field Service cases were accessed (1323 submissions). The most common bacterial isolates from specific presenting signs were identified, along with their in vitro antimicrobial susceptibility patterns. The most common site from which significant bacterial isolates were recovered was the respiratory tract, foll...

  9. Drug resistance analysis of bacterial strains isolated from burn patients.

    Science.gov (United States)

    Wang, L F; Li, J L; Ma, W H; Li, J Y

    2014-01-22

    This study aimed to analyze the spectrum and drug resistance of bacteria isolated from burn patients to provide a reference for rational clinical use of antibiotics. Up to 1914 bacterial strain specimens isolated from burn patients admitted to hospital between 2001 and 2010 were subjected to resistance monitoring by using the K-B paper disk method. Retrospective analysis was performed on drug resistance analysis of burn patients. The top eight bacterium strains according to detection rate. A total of 1355 strains of Gram-negative (G(-)) bacteria and 559 strains of Gram-positive (G(+)) bacteria were detected. The top eight bacterium strains, according to detection rate, were Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Staphylococcus epidermidis, Klebsiella pneumoniae, Enterobacter cloacae, and Enterococcus. Drug resistance rates were higher than 90% in A. baumannii, P. aeruginosa, S. epidermidis, and S. aureus, which accounted for 52.2, 21.7, 27.8, and 33.3%, respectively, of the entire sample. Those with drug resistance rates lower than 30% accounted for 4.3, 30.4, 16.7, and 16.7%, respectively. Multidrug-resistant S. aureus (MRSA) and methicillin-resistant S. epidermidis (MRSE) accounted for 49.2 and 76.4% of the S. epidermis and S. aureus resistance, respectively. Antibacterial drugs that had drug resistance rates to MRSE and MRSA higher than 90% accounted for 38.9 and 72.2%, respectively, whereas those with lower than 30% drug resistance rates accounted for 11.1 and 16.7%, respectively. The burn patients enrolled in the study were mainly infected with G(-) bacteria. These results strongly suggest that clinicians should practice rational use of antibiotics based on drug susceptibility test results.

  10. Glyphosate Utilization as the Source of Carbon: Isolation and Identification of new Bacteria

    Directory of Open Access Journals (Sweden)

    M. Mohsen Nourouzi

    2011-01-01

    Full Text Available Mixed bacteria from oil palm plantation soil (OPS were isolated to investigate their ability to utilize glyphosate as carbon source. Results showed that approximately all of the glyphosate was converted to aminomethyl-phosphonic acid (AMPA (99.5%. It is worthy to note that mixed bacteria were able to degrade only 2% of AMPA to further metabolites. Two bacterial strains i.e. Stenotrophomonas maltophilia and Providencia alcalifaciens were obtained from enrichment culture. Bacterial isolates were cultured individually on glyphosate as a sole carbon source. It was observed that both isolates were able to convert glyphosate to AMPA.

  11. Identification, Characterization and Antibiotic Resistance of Bacterial Isolates Obtained from Waterpipe Device Hoses

    Directory of Open Access Journals (Sweden)

    Majed M. Masadeh

    2015-05-01

    Full Text Available The general lack of knowledge about the health effects of waterpipe smoking is among the reasons for its global spread. In this study, bacterial contamination of waterpipe hoses was investigated. Twenty hoses were collected from waterpipe cafés and screened for bacterial pathogens using standard culture and isolation techniques. Additionally, resistance of isolated bacteria to common antibiotics was determined by identifying the minimum inhibitory concentration (MIC of each isolate. Forty eight bacterial isolates were detected. Isolates included both Gram-positive and Gram-negative pathogens from species that included Micrococcus (12, Corynebacterium (13 and Bacillus (9. In addition, some of the detected pathogens were found to be resistant to aztreonam (79%, cefixime (79%, norfloxacin, amoxicillin (47%, clarithromycin (46% and enrofloxacin (38%. In conclusion, the hose of the waterpipe device is a good environment for the growth of bacterial pathogens, which can then be transmitted to users.

  12. Identification, characterization and antibiotic resistance of bacterial isolates obtained from waterpipe device hoses.

    Science.gov (United States)

    Masadeh, Majed M; Hussein, Emad I; Alzoubi, Karem H; Khabour, Omar; Shakhatreh, Muhamad Ali K; Gharaibeh, Mahmoud

    2015-05-13

    The general lack of knowledge about the health effects of waterpipe smoking is among the reasons for its global spread. In this study, bacterial contamination of waterpipe hoses was investigated. Twenty hoses were collected from waterpipe cafés and screened for bacterial pathogens using standard culture and isolation techniques. Additionally, resistance of isolated bacteria to common antibiotics was determined by identifying the minimum inhibitory concentration (MIC) of each isolate. Forty eight bacterial isolates were detected. Isolates included both Gram-positive and Gram-negative pathogens from species that included Micrococcus (12), Corynebacterium (13) and Bacillus (9). In addition, some of the detected pathogens were found to be resistant to aztreonam (79%), cefixime (79%), norfloxacin, amoxicillin (47%), clarithromycin (46%) and enrofloxacin (38%). In conclusion, the hose of the waterpipe device is a good environment for the growth of bacterial pathogens, which can then be transmitted to users.

  13. Pseudomonas floridensis sp. nov., a bacterial pathogen isolated from tomato.

    Science.gov (United States)

    Timilsina, Sujan; Minsavage, Gerald V; Preston, James; Newberry, Eric A; Paret, Matthews L; Goss, Erica M; Jones, Jeffrey B; Vallad, Gary E

    2018-01-01

    An unusual fluorescent pseudomonad was isolated from tomato exhibiting leaf spot symptoms similar to bacterial speck. Strains were fluorescent, oxidase- and arginine-dihydrolase-negative, elicited a hypersensitive reaction on tobacco and produced a soft rot on potato slices. However, the strains produced an unusual yellow, mucoid growth on media containing 5 % sucrose that is not typical of levan. Based on multilocus sequence analysis using 16S rRNA, gap1, gltA, gyrB and rpoD, these strains formed a distinct phylogenetic group in the genus Pseudomonas and were most closely related to Pseudomonas viridiflava within the Pseudomonassyringae complex. Whole-genome comparisons, using average nucleotide identity based on blast, of representative strain GEV388 T and publicly available genomes representing the genus Pseudomonas revealed phylogroup 7 P. viridiflava strain UASW0038 and P. viridiflava type strain ICMP 2848 T as the closest relatives with 86.59 and 86.56 % nucleotide identity, respectively. In silico DNA-DNA hybridization using the genome-to-genome distance calculation method estimated 31.1 % DNA relatedness between GEV388 T and P. viridiflava ATCC 13223 T , strongly suggesting the strains are representatives of different species. These results together with Biolog GEN III tests, fatty acid methyl ester profiles and phylogenetic analysis using 16S rRNA and multiple housekeeping gene sequences demonstrated that this group represents a novel species member of the genus Pseudomonas. The name Pseudomonas floridensis sp. nov. is proposed with GEV388 T (=LMG 30013 T =ATCC TSD-90 T ) as the type strain.

  14. Microbial Observatory (ISS-MO): Study of BSL-2 bacterial isolates from the International Space Station

    Data.gov (United States)

    National Aeronautics and Space Administration — In an on-going Microbial Observatory experimental investigation on the International Space Station (ISS) multiple bacterial isolates of Biosafety Level 2 (BSL-2)...

  15. Isolation of the bacterial causes of tonsillitis in dogs

    Directory of Open Access Journals (Sweden)

    B. Al-Mufti

    2014-06-01

    Full Text Available The study was performed to identify the bacterial causes of tonsillitis in dogs. Twelve clinical cases of dogs (5 males and 7 females of different ages and breeds were observed. Tonsils swabs were taken from all the dogs, then cultured on different agars and bacterial smears prepared from all cultures and Gram stains were done. The study confirmed that the most bacterial causes of tonsillitis in dogs were Escherichia coli, Staphylococcus aureus, Staphylococcus intermedius, Staphylococcus albus, Streptococcus pyogenes, Klebsiella spp. and Pasteurella spp.

  16. Chemically synthesized silver nanoparticles as cell lysis agent for bacterial genomic DNA isolation

    Science.gov (United States)

    Goswami, Gunajit; Boruah, Himangshu; Gautom, Trishnamoni; Jyoti Hazarika, Dibya; Barooah, Madhumita; Boro, Robin Chandra

    2017-12-01

    Silver nanoparticles (AgNPs) have seen a recent spurt of use in varied fields of science. In this paper, we showed a novel application of AgNP as a promising microbial cell-lysis agent for genomic DNA isolation. We utilized chemically synthesized AgNPs for lysing bacterial cells to isolate their genomic DNA. The AgNPs efficiently lysed bacterial cells to yield good quality DNA that could be subsequently used for several molecular biology works.

  17. Evolutionary Genetic Analysis Uncovers Multiple Species with Distinct Habitat Preferences and Antibiotic Resistance Phenotypes in the Stenotrophomonas maltophilia Complex

    Directory of Open Access Journals (Sweden)

    Luz E. Ochoa-Sánchez

    2017-08-01

    Full Text Available The genus Stenotrophomonas (Gammaproteobacteria has a broad environmental distribution. Stenotrophomonas maltophilia is its best known species because it is a globally emerging, multidrug-resistant (MDR, opportunistic pathogen. Members of this species are known to display high genetic, ecological and phenotypic diversity, forming the so-called S. maltophilia complex (Smc. Heterogeneous resistance and virulence phenotypes have been reported for environmental Smc isolates of diverse ecological origin. We hypothesized that this heterogeneity could be in part due to the potential lumping of several cryptic species in the Smc. Here we used state-of-the-art phylogenetic and population genetics methods to test this hypothesis based on the multilocus dataset available for the genus at pubmlst.org. It was extended with sequences from complete and draft genome sequences to assemble a comprehensive set of reference sequences. This framework was used to analyze 108 environmental isolates obtained in this study from the sediment and water column of four rivers and streams in Central Mexico, affected by contrasting levels of anthropogenic pollution. The aim of the study was to identify species in this collection, defined as genetically cohesive sequence clusters, and to determine the extent of their genetic, ecological and phenotypic differentiation. The multispecies coalescent, coupled with Bayes factor analysis was used to delimit species borders, together with population genetic structure analyses, recombination and gene flow estimates between sequence clusters. These analyses consistently revealed that the Smc contains at least 5 significantly differentiated lineages: S. maltophilia and Smc1 to Smc4. Only S. maltophilia was found to be intrinsically MDR, all its members expressing metallo-β-lactamases (MBLs. The other Smc lineages were not MDR and did not express MBLs. We also obtained isolates related to S. acidaminiphila, S. humi and S. terrae. They

  18. Bacterial communities in petroleum oil in stockpiles.

    Science.gov (United States)

    Yoshida, Nobuyuki; Yagi, Kazuhiro; Sato, Daisuke; Watanabe, Noriko; Kuroishi, Takeshi; Nishimoto, Kana; Yanagida, Akira; Katsuragi, Tohoru; Kanagawa, Takahiro; Kurane, Ryuichiro; Tani, Yoshiki

    2005-02-01

    Bacterial communities in crude-oil samples from Japanese oil stockpiles were investigated by 16S rRNA gene cloning, followed by denaturing gradient gel electrophoresis (DGGE) analysis. 16S rRNA genes were successfully amplified by PCR after isooctane treatment from three kinds of crude-oil sample collected at four oil stockpiles in Japan. DGGE profiles showed that bacteria related to Ochrobactrum anthropi, Burkholderia cepacia, Stenotrophomonas maltophilia, Propionibacterium acnes, and Brevundimonas diminuta were frequently detected in most crude-oil samples. The bacterial communities differed in the sampling time and layer. Among the predominant bacteria detected in the crude oil, only three species were found for bacteria isolated on agar plates and were related to Burkholderia, Stenotrophomonas, and Propionibacterium, while Ochrobactrum sp. could not be isolated although this species seemed to be the most abundant bacterium in crude oil from the DGGE profiles. Using an archaea-specific primer set, methanogens were found in crude-oil sludge but not in crude-oil samples, indicating that methanogens might be involved in sludge formation in oil stockpiles.

  19. Antibacterial activity of some disinfectants, essential oils and radiation against some bacterial isolates

    International Nuclear Information System (INIS)

    Ramadan, A.B.; Abo-State, M.A.M.; Ghaly, M.F.; Ezzat, S.M.; Hefni, H.M.I.

    2006-01-01

    Nosocomial bacteria has been considered problems for all hospitals. Bacterial isolates of the present study were isolated from Sharkia Hospitals, Egypt. The isolates were S. aureus, P. aeruginosa, E. coli, Klebsiella spp., Citrobacter spp., Enterobacter spp., Proteus spp., Serratia spp. and S. epidermidis. Two disinfectants (savlon and phenolics) were examined against all the bacterial isolates at the hospitals recommended concentrations to determine the most resistance bacterial isolates. Twelve essential oils, ultraviolet radiation, Gamma radiation and laser were tested against the most resistant bacterial isolates to disinfectants and antiseptics. These bacterial isolates were S. aureus and P. aeruginosa. The most effective concentration of savlon was 2%, while that of phenolics were 4 and 5% . Fumigation of essential oils of Eugenia caryophyllata L., Marjorum hortensis L., Foeniculum vulgare L., Rosmarinus officinalis L. and Thymus vulgaris L. had high effects against these bacterial isolates. Rosmarinus officinalis L., Marjorum hortensis L., Eugenia caryophyllata L. and Thymus vulgaris L. essential oils had high effects on bacterial isolates by disc diffusion method. Matricaria chamomilla L. and Eucalyptus spp. oils had no effects against P. aeruginosa. Both essential oils of Jasminum gradiflocum L. and Jasminum sambac L. had no effects by fumigation and diffused essential oils. Ultraviolet irradiation had lethal effect on S. aureus when it exposed to ultraviolet for 10 minutes at a distance of 20 cm, while it had a lethal effect on P. aeruginosa when exposed to the rays for 7 minutes at the same distance. Gamma irradiation had lethal effect on P. aeruginosa and S. aureus at 2.5 and 3 KGy, respectively. Laser had a lethal effect on P. aeruginosa and S. aureus after 14 and 15 minutes of exposure, respectively

  20. Isolation, identification and characterization of Bacillus amyloliquefaciens BZ-6, a bacterial isolate for enhancing oil recovery from oily sludge.

    Science.gov (United States)

    Liu, Wuxing; Wang, Xiaobing; Wu, Longhua; Chen, Mengfang; Tu, Chen; Luo, Yongming; Christie, Peter

    2012-06-01

    Over 100 biosurfactant-producing microorganisms were isolated from oily sludge and petroleum-contaminated soil from Shengli oil field in north China. Sixteen of the bacterial isolates produced biosurfactants and reduced the surface tension of the growth medium from 71 to identification, isolate BZ-6 was identified as Bacillus amyloliquefaciens. The biosurfactant produced by isolate BZ-6 was purified and analyzed by high performance liquid chromatography-electrospray ionization tandem mass spectrometry. There were four ion peaks representing four different fengycin A homologues. Copyright © 2012. Published by Elsevier Ltd.

  1. The role indigenous bacterial isolates for bioremediation agent in the uranium contaminated aquatic environment

    International Nuclear Information System (INIS)

    Mochd Yazid

    2014-01-01

    A Research on the role of indigenous bacterial isolates for bio-remediation agent of the uranium contaminated in the aquatic environment has been conducted. The objective of the research is to study the role of Pseudomonas sp and Bacillus sp. have been isolated from low level uranium waste for bioremediation agent in their environment, such as the determination of efficiency of the uranium binding compared by the non indigenous bacterial, location of these binding and the influences of added acethyl acid stimulant. The uranium reduction studied was measured by weighting bacterial biomass and uranium concentration was measured by spectrophotometer. The acethyl acid stimulant addition has been done with the variation of concentration and volume. The efficiency of the uranium reduction by indigenous bacterial isolate such as Pseudomonas sp were 84.99 % and Bacillus sp were 52.70 %, so the reduction efficiency by non indigenous bacterial such as Pseudomonas aerogenes were 78.47 % and Bacillus subtilis were 45.22 % for 54 hours incubation time. The result of this research can be concluded that Pseudomonas sp and Bacillus sp. Indigenous bacterial have been isolates from the liquid uranium waste can contributed in bioremediation agent for uranium radionuclide in the environment for 60 ppm concentration with reduction efficiency 52.70 %-84.99 %, that is higher non indigenous bacterial for 54 hours incubation time, the stimulant addition of acethyl acid, the efficiency can be increased up to 99.8 %. (author)

  2. Characterization of copper-resistant bacteria and bacterial communities from copper-polluted agricultural soils of central Chile

    Directory of Open Access Journals (Sweden)

    Altimira Fabiola

    2012-09-01

    Full Text Available Abstract Background Copper mining has led to Cu pollution in agricultural soils. In this report, the effects of Cu pollution on bacterial communities of agricultural soils from Valparaiso region, central Chile, were studied. Denaturing gradient gel electrophoresis (DGGE of the 16S rRNA genes was used for the characterization of bacterial communities from Cu-polluted and non-polluted soils. Cu-resistant bacterial strains were isolated from Cu-polluted soils and characterized. Results DGGE showed a similar high number of bands and banding pattern of the bacterial communities from Cu-polluted and non-polluted soils. The presence of copA genes encoding the multi-copper oxidase that confers Cu-resistance in bacteria was detected by PCR in metagenomic DNA from the three Cu-polluted soils, but not in the non-polluted soil. The number of Cu-tolerant heterotrophic cultivable bacteria was significantly higher in Cu-polluted soils than in the non-polluted soil. Ninety two Cu-resistant bacterial strains were isolated from three Cu-polluted agricultural soils. Five isolated strains showed high resistance to copper (MIC ranged from 3.1 to 4.7 mM and also resistance to other heavy metals. 16S rRNA gene sequence analyses indicate that these isolates belong to the genera Sphingomonas, Stenotrophomonas and Arthrobacter. The Sphingomonas sp. strains O12, A32 and A55 and Stenotrophomonas sp. C21 possess plasmids containing the Cu-resistance copA genes. Arthrobacter sp. O4 possesses the copA gene, but plasmids were not detected in this strain. The amino acid sequences of CopA from Sphingomonas isolates (O12, A32 and A55, Stenotrophomonas strain (C21 and Arthrobacter strain (O4 are closely related to CopA from Sphingomonas, Stenotrophomonas and Arthrobacter strains, respectively. Conclusions This study suggests that bacterial communities of agricultural soils from central Chile exposed to long-term Cu-pollution have been adapted by acquiring Cu genetic determinants

  3. ANTIBIOTIC RESISTANCE IN THE OPPORTUNISTIC PATHOGEN STENOTROPHOMONAS MALTOPHILIA

    Directory of Open Access Journals (Sweden)

    María Blanca Sánchez

    2015-06-01

    Full Text Available Stenotrophomonas maltophilia is an environmental bacterium found in the soil, associated with plants and animals, and in aquatic environments. It is also an opportunistic pathogen now causing an increasing number of nosocomial infections. The treatment of S. maltophilia is quite difficult given its intrinsic resistance to a number of antibiotics, and because it is able to acquire new resistances via horizontal gene transfer and mutations. Certainly, strains resistant to quinolones, cotrimoxale and/or cephalosporins - antibiotics commonly used to treat S. maltophilia infections - have emerged. The increasing number of available S. maltophilia genomes has allowed the identification and annotation of a large number of antimicrobial and heavy metal resistance genes. Most encode inactivating enzymes and efflux pumps, but information on their role in intrinsic and acquired resistance is limited. Non-typical antibiotic resistance mechanisms that also form part of the intrinsic resistome have been identified via mutant library screening. These include non-typical antibiotic resistance genes, such as bacterial metabolism genes, and non-inheritable resistant phenotypes, such as biofilm formation and persistence. Their relationships with resistance are complex and require further study.

  4. Bacterial Profile and Antimicrobial Susceptibility Pattern of Isolates ...

    African Journals Online (AJOL)

    Frequent isolates were S. aureus, (34.04%), and P. aeruginosa, (31.8%). About 82.16% of the isolates showed multiple resistances. In light of our findings, regular antibiotic resistance test has to be done for each patient in order to select an appropriate antimicrobial agent. Keywords: Bacteraemia, Burn, Sepsis, Thermal ...

  5. DNA fingerprinting of spore-forming bacterial isolates, using Bacillus ...

    African Journals Online (AJOL)

    User

    Bc-repetitive extragenic palindromic polymerase chain reaction (Bc-Rep PCR) analysis was conducted on seven Bacillus thuringiensis isolates accessed from the Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ) culture collection and on five local isolates of entomopathogenic spore- forming bacteria.

  6. Degradation of petroleum hydrocarbons by oil field isolated bacterial ...

    African Journals Online (AJOL)

    A mixed consortium was prepared with 15 bacteria isolated by enrichment technique from the sample collected from an oil contaminated site. This consortium was incubated with crude oil to investigate the metabolic capability of bacteria. The degradation efficiency of the isolates in consortium was checked with 2% crude oil ...

  7. DNA fingerprinting of spore-forming bacterial isolates, using Bacillus ...

    African Journals Online (AJOL)

    Bc-repetitive extragenic palindromic polymerase chain reaction (Bc-Rep PCR) analysis was conducted on seven Bacillus thuringiensis isolates accessed from the Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ) culture collection and on five local isolates of entomopathogenic spore-forming bacteria.

  8. Isolation of Enterobacter cowanii from Eucalyptus showing symptoms of bacterial blight and dieback in Uruguay.

    Science.gov (United States)

    Brady, C L; Venter, S N; Cleenwerck, I; Engelbeen, K; de Vos, P; Wingfield, M J; Telechea, N; Coutinho, T A

    2009-10-01

    This study was performed to identify bacterial strains isolated simultaneously with Pantoea species from Eucalyptus trees showing symptoms of bacterial blight and dieback in Uruguay. Several molecular techniques including 16S rRNA and rpoB gene sequencing and DNA-DNA hybridization were used to characterize the gram-negative, facultatively anaerobic, slime-producing bacterial strains isolated along with Pantoea species from Eucalyptus. Hypersensitivity reactions (HR) and pathogenicity tests were performed on tobacco and Eucalyptus seedlings, respectively. The isolates clustered closely with the type strain of Enterobacter cowanii in both phylogenetic trees constructed. The DNA-DNA similarity between the isolates and the type strain of Ent. cowanii ranged from 88% to 92%. A positive HR was observed on the tobacco seedlings, but no disease symptoms were visible on the inoculated Eucalyptus seedlings. Enterobacter cowanii was isolated from trees with symptoms of bacterial blight although strains of this bacterial species do not appear to be the causal agent of the disease. This study provides the first report of Ent. cowanii isolated from Eucalyptus. Its presence in Eucalyptus tissue suggests that it is an endophyte in trees showing symptoms of blight.

  9. Stenotrophomonas maltophilia: From trivial to grievous

    Directory of Open Access Journals (Sweden)

    Lipika Singhal

    2017-01-01

    Full Text Available Stenotrophomonas maltophilia, once regarded as an organism of low virulence, has evolved as a significant opportunistic pathogen causing severe human infections in both hospital and community settings, especially amongst highly debilitated patients. Globally, S. maltophilia ranks third amongst the four most common pathogenic non-fermenting Gram-negative bacilli (NFGNBs, others being Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia complex (Bcc. The worth of accurate identification of S. maltophilia comes to the forefront as it needs to be differentiated from other NFGNBs such as Acinetobacter, P. aeruginosa and Bcc due to its inherently contrasting antibiotic susceptibility pattern. Consequently, its correct identification is essential as no single drug is amply effective against all NFGNBs, which hinders initiation of appropriate empirical treatment resulting in increased morbidity and mortality.

  10. An isolated bacterial consortium for crude oil biodegradation

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... designed using DesignExpert 6.0.8 software by optimizing the amount of crude oil, microbial inoculum and sludge which are initially ... Key words: Crude oil, bacterial consortium, kinetics, bioremediation, biostimulation, natural attenuation. ... For the preparation of the consortiums, colonies were plated on.

  11. Drug resistance patterns of bacterial isolates from infected wounds ...

    African Journals Online (AJOL)

    unhcc

    Conclusions: High frequency of mono and multi-drug resistant bacterial pathogens were documented. Thus, an alternative method to the causative agent and antimicrobial susceptibility testing surveillance in areas where there is no culture facility is needed to assist health professionals for the selection of appropriate ...

  12. Bacterial Isolates andAntibiotic Sensitivity in Community Acquired ...

    African Journals Online (AJOL)

    Objective: The objective of the studywas to determine bacterial causes of community acquired pneumonia and their antibiotic sensitivity pattern amongst patients admitted intomedicalwards inAminu Kano Teaching Hospital, Kano, Nigeria Methods: The study incorporated patients aged fifteen years and above admitted into ...

  13. Sensitivity pattern of bacterial isolates in childhood sepsis in clinical ...

    African Journals Online (AJOL)

    To determine the commonest organism cultured from the blood of children suspected to have bacterial sepsis and their antibiogram sensitivity using the commonly used antibiotics in a private practice and see if there are differences from established data from other areas. Children beyond neonatal age presenting to a ...

  14. Antibiogram of bacterial pathogens isolated from subclinical mastitis ...

    African Journals Online (AJOL)

    The present investigation was carried out to study the prevalence of bacterial pathogens responsible for subclinical mastitis in cattle and their antibiogram pattern to selected antibiotics. The study was carried out on lactating cows in small holder dairy farms in and around Kombolcha, South Wollo, Amhara region, Ethiopia.

  15. Comparison of protease production from newly isolated bacterial ...

    African Journals Online (AJOL)

    Fermentation medium (by using sub-merged fermentation technique) was incubated for 48 h at 37°C temperature and agitation speed of 200 rpm. The protease was partially purified with 70% ammonium sulphate. Four different supports were used for the immobilization of the bacterial protease by physical adsorption ...

  16. Investigation of In vitro Mineral Forming Bacterial Isolates from ...

    African Journals Online (AJOL)

    2018-01-30

    Jan 30, 2018 ... bacterial colony in the oral cavity is important in calculus formation because bacteria have a direct effect on the pH ... Department of Biology,. Faculty of Science, Atatürk. University, 1Department of ... performed with oral bacteria in environments with high ion levels, and thus, their findings have very limited.

  17. Antibiotic Activity Assessment of Bacterial Strains Isolated from Urine ...

    African Journals Online (AJOL)

    Urinary tract infections (UTI) are common worldwide and affect all sexes and age groups. An estimated 20% or more of the female population suffers from some form of UTIs in their lifetime. Although antibiotics are the first choice of treatment for many urinary tract infections, antibiotic-resistant strains of bacterial species ...

  18. Antibacterial and cytotoxic efficacy of extracellular silver nanoparticles biofabricated from chromium reducing novel OS4 strain of Stenotrophomonas maltophilia.

    Directory of Open Access Journals (Sweden)

    Mohammad Oves

    Full Text Available Biofabricated metal nanoparticles are generally biocompatible, inexpensive, and ecofriendly, therefore, are used preferably in industries, medical and material science research. Considering the importance of biofabricated materials, we isolated, characterized and identified a novel bacterial strain OS4 of Stenotrophomonas maltophilia (GenBank: JN247637.1. At neutral pH, this Gram negative bacterial strain significantly reduced hexavalent chromium, an important heavy metal contaminant found in the tannery effluents and minings. Subsequently, even at room temperature the supernatant of log phase grown culture of strain OS4 also reduced silver nitrate (AgNO3 to generate nanoparticles (AgNPs. These AgNPs were further characterized by UV-visible, Nanophox particle size analyzer, XRD, SEM and FTIR. As evident from the FTIR data, plausibly the protein components of supernatant caused the reduction of AgNO3. The cuboid and homogenous AgNPs showed a characteristic UV-visible peak at 428 nm with average size of ~93 nm. The XRD spectra exhibited the characteristic Bragg peaks of 111, 200, 220 and 311 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. From the nanoparticle release kinetics data, the rapid release of AgNPs was correlated with the particle size and increasing surface area of the nanoparticles. A highly significant antimicrobial activity against medically important bacteria by the biofabricated AgNPs was also revealed as decline in growth of Staphylococcus aureus (91%, Escherichia coli (69% and Serratia marcescens (66% substantially. Additionally, different cytotoxic assays showed no toxicity of AgNPs to liver function, RBCs, splenocytes and HeLa cells, hence these particles were safe to use. Therefore, this novel bacterial strain OS4 is likely to provide broad spectrum benefits for curing chromium polluted sites, for biofabrication of AgNPs and ultimately in the

  19. Transfer of Pseudomonas pictorum Gray and Thornton 1928 to genus Stenotrophomonas as Stenotrophomonas pictorum comb. nov., and emended description of the genus Stenotrophomonas.

    Science.gov (United States)

    Ouattara, Aboubakar Sidiki; Le Mer, Jean; Joseph, Manon; Macarie, Hervé

    2017-06-01

    A polyphasic taxonomic approach including analysis of phenotypic, physiological and genotypic characteristics, 16S rRNA gene sequence and DNA-DNA hybridization analysis was used to determine the most consistent affiliation of Pseudomonas pictorum. Pseudomonas pictorum ATCC 23328T exhibited phenotypic traits of members of the genus Stenotrophomonas including cellular fatty acid composition, quinone and limited range of substrates that could be used. Antibiotic susceptibility and physiological characteristics were determined. The DNA G+C content was 65.7 mol%. Phylogenetic analysis revealed that the type strains of Stenotrophomonas terrae, Stenotrophomonashumi, Stenotrophomonasnitritireducens and Stenotrophomonasacidaminiphila were the nearest relatives (16S rRNA gene sequence similarity of 98.0 to 98.8 %). All the other type strains of species of the genus Stenotrophomonas showed high 16S rRNA gene sequence similarities (96.8 to 97.2 %). DNA-DNA hybridizations revealed 31.0, 32.0, 43.3 and 43.6 % reassociation between Pseudomonas pictorum ATCC 23328T and the type strains of S. terrae, S. humi, S. nitritireducens and S. acidaminiphila, respectively. Our overall results indicate that Pseudomonas pictorum should be transferred to the genus Stenotrophomonas as a novel species of this genus, Stenotrophomonas pictorum comb. nov. Since the original description of the genus Stenotrophomonaswas made with only one species (Stenotrophomonasmaltophilia), an emendation of the genus description is proposed in order to match better with the characteristics of the eleven novel species assigned to this genus since then.

  20. MALDI-TOF mass spectrometry proteomic based identification of clinical bacterial isolates

    Directory of Open Access Journals (Sweden)

    Ashutosh Panda

    2014-01-01

    Full Text Available Background & objectives: Pathogenic bacteria often cause life threatening infections especially in immunocompromised individuals. Therefore, rapid and reliable species identification is essential for a successful treatment and disease management. We evaluated a rapid, proteomic based technique for identification of clinical bacterial isolates by protein profiling using matrix-assisted laser desorption-ionization time - of - flight mass spectrometry (MALDI-TOF MS. Methods: Freshly grown bacterial isolates were selected from culture plates. Ethanol/formic acid extraction procedure was carried out, followed by charging of MALDI target plate with the extract and overlaying with α-cyano-4 hydroxy-cinnamic acid matrix solution. Identification was performed using the MALDI BioTyper 1.1, software for microbial identification (Bruker Daltonik GmbH, Bremen, Germany. Results: A comparative analysis of 82 clinical bacterial isolates using MALDI -TOF MS and conventional techniques was carried out. Amongst the clinical isolates, the accuracy at the species level for clinical isolates was 98.78%. One out of 82 isolates was not in accordance with the conventional assays because MALDI-TOF MS established it as Streptococcus pneumoniae and conventional methods as Streptococcus viridans. Interpretation & conclusions: MALDI - TOF MS was found to be an accurate, rapid, cost-effective and robust system for identification of clinical bacterial isolates. This innovative approach holds promise for earlier therapeutic intervention leading to better patient care.

  1. An isolated bacterial consortium for crude oil biodegradation

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    ) and tested for their ability to degrade COCS. ... Environmental pollution, especially with hydrocarbons is a major environmental ..... Rhodochrous Isolated from Soil and Marine Environments in Kuwait. Environ. Pollut. 65: 1-17 ...

  2. Phylogenetic distribution of virulence-associated genes among Escherichia coli isolates associated with neonatal bacterial meningitis in the Netherlands

    NARCIS (Netherlands)

    Johnson, James R.; Oswald, Eric; O'Bryan, Timothy T.; Kuskowski, Michael A.; Spanjaard, Lodewijk

    2002-01-01

    Seventy cerebrospinal fluid Escherichia coli isolates from infants with neonatal bacterial meningitis (NBM), as submitted to the Netherlands Reference Laboratory for Bacterial Meningitis from 1989 through 1997, were assessed for phylogenetic background and extended virulence genotypes, in comparison

  3. Isolation, Screening and Development of Local Bacterial Consortia With Azo Dyes Decolourising Capability

    Directory of Open Access Journals (Sweden)

    Khadijah, O.

    2009-01-01

    Full Text Available A total of 1540 bacterial isolates were isolated and screened for their ability to degrade selected azo dyes. Of these, nine isolates were chosen for further studies based on their ability to degrade a wide spectrum of dyes efficiently and rapidly. Several microbial consortia were developed and tested for their effectiveness. Overall the consortia were able to degrade 70 - 100% colour within 72 hours compared to 60 – 97% colour removed by individual isolates. A microbial consortium labelled C15 showed good growth in agitation culture but the colour removal was best in static culture with 80 - 100% colour removed in less than 72 hours. Based on the 16S rRNA sequencing, two of the bacterial isolates in C15 belong to the Chryseobacterium genus while the other one belongs to Flavobacterium genus.

  4. Resistance of Stenotrophomonas maltophilia to Fluoroquinolones: Prevalence in a University Hospital and Possible Mechanisms.

    Science.gov (United States)

    Jia, Wei; Wang, Jiayuan; Xu, Haotong; Li, Gang

    2015-05-13

    The purpose of this study was to investigate the clinical distribution and genotyping of Stenotrophomonas maltophilia, its resistance to antimicrobial agents, and the possible mechanisms of this drug resistance. S. maltophilia isolates were collected from clinical specimens in a university hospital in Northwestern China during the period between 2010 and 2012, and were identified to the species level with a fully automated microbiological system. Antimicrobial susceptibility testing was performed for S. maltophilia with the Kirby-Bauer disc diffusion method. The minimal inhibitory concentrations (MICs) of norfloxacin, ofloxacin, chloramphenicol, minocycline, ceftazidime, levofloxacin and ciprofloxacin against S. maltophilia were assessed using the agar dilution method, and changes in the MIC of norfloxacin, ciprofloxacin and ofloxacin were observed after the addition of reserpine, an efflux pump inhibitor. Fluoroquinolone resistance genes were detected in S. maltophilia using a polymerase chain reaction (PCR) assay, and the expression of efflux pump smeD and smeF genes was determined using a quantitative fluorescent (QF)-PCR assay. Pulsed-field gel electrophoresis (PFGE) was employed to genotype identified S. maltophilia isolates. A total of 426 S. maltophilia strains were isolated from the university hospital from 2010 to 2012, consisting of 10.1% of total non-fermentative bacteria. The prevalence of norfloxacin, ciprofloxacin and ofloxacin resistance was 32.4%, 21.9% and 13.2% in the 114 S. maltophilia isolates collected from 2012, respectively. Following reserpine treatment, 19 S. maltophilia isolates positive for efflux pump were identified, and high expression of smeD and smeF genes was detected in two resistant isolates. gyrA, parC, smeD, smeE and smeF genes were detected in all 114 S. maltophilia isolates, while smqnr gene was found in 25.4% of total isolates. Glu-Lys mutation (GAA-AAA) was detected at the 151th amino acid of the gyrA gene, while Gly

  5. Resistance of Stenotrophomonas maltophilia to Fluoroquinolones: Prevalence in a University Hospital and Possible Mechanisms

    Directory of Open Access Journals (Sweden)

    Wei Jia

    2015-05-01

    Full Text Available Objective: The purpose of this study was to investigate the clinical distribution and genotyping of Stenotrophomonas maltophilia, its resistance to antimicrobial agents, and the possible mechanisms of this drug resistance. Methods: S. maltophilia isolates were collected from clinical specimens in a university hospital in Northwestern China during the period between 2010 and 2012, and were identified to the species level with a fully automated microbiological system. Antimicrobial susceptibility testing was performed for S. maltophilia with the Kirby-Bauer disc diffusion method. The minimal inhibitory concentrations (MICs of norfloxacin, ofloxacin, chloramphenicol, minocycline, ceftazidime, levofloxacin and ciprofloxacin against S. maltophilia were assessed using the agar dilution method, and changes in the MIC of norfloxacin, ciprofloxacin and ofloxacin were observed after the addition of reserpine, an efflux pump inhibitor. Fluoroquinolone resistance genes were detected in S. maltophilia using a polymerase chain reaction (PCR assay, and the expression of efflux pump smeD and smeF genes was determined using a quantitative fluorescent (QF-PCR assay. Pulsed-field gel electrophoresis (PFGE was employed to genotype identified S. maltophilia isolates. Results: A total of 426 S. maltophilia strains were isolated from the university hospital from 2010 to 2012, consisting of 10.1% of total non-fermentative bacteria. The prevalence of norfloxacin, ciprofloxacin and ofloxacin resistance was 32.4%, 21.9% and 13.2% in the 114 S. maltophilia isolates collected from 2012, respectively. Following reserpine treatment, 19 S. maltophilia isolates positive for efflux pump were identified, and high expression of smeD and smeF genes was detected in two resistant isolates. gyrA, parC, smeD, smeE and smeF genes were detected in all 114 S. maltophilia isolates, while smqnr gene was found in 25.4% of total isolates. Glu-Lys mutation (GAA-AAA was detected at the 151th

  6. Resistance of Stenotrophomonas maltophilia to Fluoroquinolones: Prevalence in a University Hospital and Possible Mechanisms

    Science.gov (United States)

    Jia, Wei; Wang, Jiayuan; Xu, Haotong; Li, Gang

    2015-01-01

    Objective: The purpose of this study was to investigate the clinical distribution and genotyping of Stenotrophomonas maltophilia, its resistance to antimicrobial agents, and the possible mechanisms of this drug resistance. Methods: S. maltophilia isolates were collected from clinical specimens in a university hospital in Northwestern China during the period between 2010 and 2012, and were identified to the species level with a fully automated microbiological system. Antimicrobial susceptibility testing was performed for S. maltophilia with the Kirby-Bauer disc diffusion method. The minimal inhibitory concentrations (MICs) of norfloxacin, ofloxacin, chloramphenicol, minocycline, ceftazidime, levofloxacin and ciprofloxacin against S. maltophilia were assessed using the agar dilution method, and changes in the MIC of norfloxacin, ciprofloxacin and ofloxacin were observed after the addition of reserpine, an efflux pump inhibitor. Fluoroquinolone resistance genes were detected in S. maltophilia using a polymerase chain reaction (PCR) assay, and the expression of efflux pump smeD and smeF genes was determined using a quantitative fluorescent (QF)-PCR assay. Pulsed-field gel electrophoresis (PFGE) was employed to genotype identified S. maltophilia isolates. Results: A total of 426 S. maltophilia strains were isolated from the university hospital from 2010 to 2012, consisting of 10.1% of total non-fermentative bacteria. The prevalence of norfloxacin, ciprofloxacin and ofloxacin resistance was 32.4%, 21.9% and 13.2% in the 114 S. maltophilia isolates collected from 2012, respectively. Following reserpine treatment, 19 S. maltophilia isolates positive for efflux pump were identified, and high expression of smeD and smeF genes was detected in two resistant isolates. gyrA, parC, smeD, smeE and smeF genes were detected in all 114 S. maltophilia isolates, while smqnr gene was found in 25.4% of total isolates. Glu-Lys mutation (GAA-AAA) was detected at the 151th amino acid of the

  7. Studies on antibiotic resistance of some bacterial isolates from ...

    African Journals Online (AJOL)

    Sachet water samples of different brands were collected from several retail outlets in Nsukka, Nigeria and analysed microbiologically to determine their bacteriological quality and antimicrobial susceptibility of the isolates. A brand of the sachet water samples tested negative for the presence of bacteria while a total of 61 ...

  8. Microbiological Assessment of Bacterial Isolates from Ear, Nose And ...

    African Journals Online (AJOL)

    Samples from patients who reported to in-patient ENT unit of Aminu Kano Teaching Hospital, Kano were isolated for further microbiological assessment. One hundred (100) from both male and female patients comprising 55 ear swabs, 30 and 15 throat and nose swabs respectively were screened between February and ...

  9. Antibiotics susceptibility patterns of urine bacterial isolates in Zaria ...

    African Journals Online (AJOL)

    Purpose: The prevalence of E. coli, Ps. aeruginosa and Staph aureus isolates from urine of selected residents in Zaria was investigated. This was an attempt to elucidate the antibiotic susceptibility profiles of these bacteria commonly implicated in urinary tact infection. Methods: Urine samples collected from students of ...

  10. Manganese oxidation by bacterial isolates from the Indian Ridge System

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, S.O.; Krishnan, K.P.; Khedekar, V.D; LokaBharathi, P.A.

    ) observations of both isolates revealed free-living cells in clustered matrices apprrox. 2 Mu diameter. Energy dispersive spectrum of the cell matrix of CR35 cultured in 1 mM Mn detected 30%Mn, while the cell aggregates of CR48 harbored 7 -10% Mn. The relatively...

  11. Incidence and Antibiotic Susceptibility Pattern of Bacterial Isolates ...

    African Journals Online (AJOL)

    Purpose: To investigate the incidence of different bacteria isolates in 150 wound infections in Aminu Kano Teaching Hospital, Kano, Nigeria and their antibacterial susceptibility patterns. Methods: Wound swab samples were collected from general culture bench of the Microbiology Department, after obtaining consent from ...

  12. Bacterial isolates of tonsillitis and pharyngitis in a paediatric casualty ...

    African Journals Online (AJOL)

    BHS and S. aureus showed 100% sensitivity to cefuroxine, azithromycin, ceftazidine and genticin. All the isolates had little or no sensitivity to ampicillin and cotrimoxazole. BHS is a significant cause of pharyngitis and tonsillitis in our environment and therefore poses a potential danger of rheumatic fever and rheumatic heart ...

  13. Incidence and Antibiotic Susceptibility Pattern of Bacterial Isolates ...

    African Journals Online (AJOL)

    Purpose: To investigate the incidence of different bacteria isolates in 150 wound infections in Aminu Kano Teaching Hospital, Kano, ... antibiotic-resistant bacteria are present in the wound sites. Keywords: Wound infection , Antibiotic, ... and injections, but post-operative wound infections in hospital are most common. Some.

  14. Increasing incidence of bacterial resistance to antibiotics by isolates ...

    African Journals Online (AJOL)

    Antibiotic sensitivity testing was performed on sensitivity test agar (Biotec, UK) using the disc diffusion method in accordance with the National Committee for Clinical Laboratory Standards (5). The results were compared with a previous study in 1993. A total of 336 urinary isolates were identified, with the coliforms being the ...

  15. The Prevalent Bacterial Isolates Of Dental Caries In School Age ...

    African Journals Online (AJOL)

    The study was conducted at the dental clinic of Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife. A total of 100 carious samples were collected from children of varying age and sexes. The bacteria isolated were S. mutans: 45.6%, Lactobacillus spp: 41.2% and S. aureus: 13.2%. Out of the 100 samples, 88(5) ...

  16. EFFECT OT KUNNU-ZAKI ON CLINICAL BACTERIAL ISOLATES

    African Journals Online (AJOL)

    omidiji

    2012-03-08

    Mar 8, 2012 ... antimicrobial effect represents another property for Kunun-zaki and obviates the possibility of public health risk in its consumption. Key words: Kunnu-zaki, clinical isolates, antibiotic sensitivity. INTRODUCTION. Kunnu-zaki is a cereal food drink that has become a popular refreshing non-alcoholic beverage ...

  17. Production of bacterial amylase by Bacillus species isolated from ...

    African Journals Online (AJOL)

    Optimum pH activity was obtained at 4.0 with a concentration of 0.376 mg/ml. Bacillus licheniformis has the greatest potential for producing amylase than the other isolates and rice husk can be exploited for amylase production. The B. licheniformis strain produced thermostable alpha-amylase with characteristics suitable for ...

  18. Isolation, Characterization and Application of Bacterial Population From Agricultural Soil at Sohag Province, Egypt

    Directory of Open Access Journals (Sweden)

    Bahig, A. E.

    2008-01-01

    Full Text Available Forty soil samples of agriculture soil were collected from two different sites in Sohag province, Egypt, during hot and cold seasons. Twenty samples were from soil irrigated with canal water (site A and twenty samples were from soil irrigated with wastewater (site B. This study aimed to compare the incidence of plasmids in bacteria isolated from soil and to investigate the occurrence of metal and antibiotic resistance bacteria, and consequently to select the potential application of these bacteria in bioremediation. The total bacterial count (CFU/gm in site (B was higher than that in site (A. Moreover, the CFU values in summer were higher than those values in winter at both sites. A total of 771 bacterial isolates were characterized as Bacillus, Micrococcus, Staphylococcus, Pseudomonas, Eschershia, Shigella, Xanthomonas, Acetobacter, Citrobacter, Enterobacter, Moraxella and Methylococcus. Minimum inhibitory concentrations (MICs of Pb+2, Cu+2, Zn+2, Hg+2, Co+2, Cd+2, Cr+3, Te+2, As+2 and Ni+2 for plasmid-possessed bacteria were determined and the highest MICs were 1200 µg/mL for lead, 800 µg/mL for both Cobalt and Arsenate, 1200 µg/mL for Nickel, 1000 µg/ml for Copper and less than 600 µg/mL for other metals. Bacterial isolates from both sites A and B showed multiple heavy metal resistance. A total of 337 bacterial isolates contained plasmids and the incidence of plasmids was approximately 25-50% higher in bacteria isolated from site (B than that from site (A. These isolates were resistance to different antibiotics. Approximately, 61% of the bacterial isolates were able to assimilate insecticide, carbaryl, as a sole source of carbon and energy. However, the Citrobacter AA101 showed the best growth on carbaryl.

  19. Bacterial isolates from Nsukka meat market: a zoonotic appraisal.

    Science.gov (United States)

    Uche, U E; Agbo, J A

    1985-06-01

    Swabs collected from butchers hands, knives, tables and meat displayed for sale at Nsukka meat market showed that every item screened was contaminated. Bacteria isolated include Streptococcus faecalis, coagulase positive Staphylococcus, Clostridium perfringens, Brucella species, Corynebacterium haemolyticum, Proteus mirabilis, P. vulgaris, Escherichia coli, Salmonella enteritidis, Enterobacter aerogenes, Pseudomonas multophilia, P. rubescens and beta-haemolytic Streptococci. The zoonotic or public health implications of such contaminations, their probable sources and possible ways of minimizing them are discussed.

  20. Bacterial Endophytes Isolated from Plants in Natural Oil Seep Soils with Chronic Hydrocarbon Contamination.

    Science.gov (United States)

    Lumactud, Rhea; Shen, Shu Yi; Lau, Mimas; Fulthorpe, Roberta

    2016-01-01

    The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum, and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species. The isolates were identified by partial 16S rDNA sequence analysis, with class Actinobacteria as the dominant group in all species except S. canadensis, which was dominated by Gammaproteobacteria. Microbacterium foliorum and Plantibacter flavus were present in all the plants, with M. foliorum showing predominance in D. glomerata and both endophytic bacterial species dominated T. aureum. More than 50% of the isolates demonstrated degradative capabilities for octanol, toluene, naphthalene, kerosene, or motor oil based on sole carbon source growth screens involving the reduction of tetrazolium dye. P. flavus isolates from all the sampled plants showed growth on all the petroleum hydrocarbons (PHCs) substrates tested. Mineralization of toluene and naphthalene was confirmed using gas-chromatography. 16S based terminal restriction fragment length polymorphism analysis revealed significant differences between the endophytic bacterial communities showing them to be plant host specific at this site. To our knowledge, this is the first account of the degradation potential of bacterial endophytes in these commonly occurring pioneer plants that were not previously known as phytoremediating plants.

  1. Preliminary screening of bacterial isolates from mining wastes

    Directory of Open Access Journals (Sweden)

    Rodino S.,

    2016-05-01

    Full Text Available Developing innovative biotechnology for obtaining new resources of high tech critical metals is strongly influenced by the need to reduce the potential risk of shortages, to support the development of industry at European level. To set up these new technologies is essential to isolate strains with high potential in bioleaching of ore, tailings and mine wastes and bioaccumulation of high tech critical metals. Microorganisms are capable of mediating metal and mineral bioprecipitation. In this paper are presented preliminary studies performed for the isolation of strains existing in mining residues containing high tech critical metals. Were used samples collected from various depths in an area of mining wastes containing high tech critical metals. The samples were fine grounded and the powder was washed with sterile saline water. Exact quantities of samples were dispersed in sterile saline water, shaken for a period of 60 minutes, diluted and plated in triplicate on selective agar. After several steps were isolated 3 strains of gram negative bacteria.

  2. Oviposition responses of Aedes mosquitoes to bacterial isolates from attractive bamboo infusions.

    Science.gov (United States)

    Ponnusamy, Loganathan; Schal, Coby; Wesson, Dawn M; Arellano, Consuelo; Apperson, Charles S

    2015-09-23

    The mosquitoes Aedes aegypti and Aedes albopictus are vectors of pathogenic viruses that cause major human illnesses including dengue, yellow fever and chikungunya. Both mosquito species are expanding their geographic distributions and now occur worldwide in temperate and tropical climates. Collection of eggs in oviposition traps (ovitraps) is commonly used for monitoring and surveillance of container-inhabiting Aedes populations by public health agencies charged with managing mosquito-transmitted illness. Addition of an organic infusion in these traps increases the number of eggs deposited. Gravid females are guided to ovitraps by volatile chemicals produced from the breakdown of organic matter by microbes. We previously isolated and cultured 14 species of bacteria from attractive experimental infusions, made from the senescent leaves of canebrake bamboo (Arundinaria gigantea). Cultures were grown for 24 h at 28 °C with constant shaking (120 rpm) and cell densities were determined with a hemocytometer. Behavioral responses to single bacterial isolates and to a mix of isolates at different cell densities were evaluated using two-choice sticky-screen bioassay methods with gravid Ae. aegypti and Ae. albopictus. In behavioral assays of a mix of 14 bacterial isolates, significantly greater attraction responses were exhibited by Ae. aegypti and Ae. albopictus to bacterial densities of 10(7) and 10(8) cells/mL than to the control medium. When we tested single bacterial isolates, seven isolates (B1, B2, B3, B5, B12, B13 and B14) were significantly attractive to Ae. aegypti, and six isolates (B1, B5, B7, B10, B13 and B14) significantly attracted Ae. albopictus. Among all the isolates tested at three different cell densities, bacterial isolates B1, B5, B13 and B14 were highly attractive to both Aedes species. Our results show that at specific cell densities, some bacteria significantly influence the attraction of gravid Ae. aegypti and Ae. albopictus females to

  3. Bacterial Endophytes Isolated from Plants in Natural Oil Seep Soils with Chronic Hydrocarbon Contamination

    OpenAIRE

    Lumactud, Rhea; Shen, Shu Yi; Lau, Mimas; Fulthorpe, Roberta

    2016-01-01

    The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species....

  4. MICROFLUIDIC MODULES FOR ISOLATION OF RECOMBINANT CYTOKINE FROM BACTERIAL LYSATES

    Energy Technology Data Exchange (ETDEWEB)

    Retterer, Scott T [ORNL; Doktycz, Mitchel John [ORNL

    2014-01-01

    The portability and personalization of health-care diagnostics and treatments benefits from advancements and applications of micro and nanotechnology. Modularization and miniaturization of standardized biochemical processes and tests facilitates the advancement and customization of analyte detection and diagnosis on-chip. The goal of our work here is to develop modular platforms for on-chip biochemical processing of synthesized biologics for a range of on-demand applications. Our report focuses on the initial development, characterization and application of microfluidic size exclusion/gel filtration and ion exchange protein concentration modules for cytokine isolation from spiked cell extracts.

  5. Isolation and Purification of Bacterial Strains from Treatment Plants for Effective and Efficient Bioconversion of Domestic Wastewater Sludge

    OpenAIRE

    K. C.A. Jalal; Md. Z.   Alam; Suleyman A.   Muyibi; P. Jamal

    2006-01-01

    Forty six bacterial strains were isolated from nine different sources in four treatment plants namely Indah Water Konsortium (IWK) sewage treatment plant, International Islamic University Malaysia (IIUM) treatment plant-1,-2 and 3 to evaluate the bioconversion process in terms of efficient biodegradation and bioseparation. The bacterial strains isolated were found to be 52.2% (24 isolates) and 47.8% (22 isolates) in the IWK and IIUM treatment plants respectively. The results showed that the h...

  6. 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.

  7. Isolation of Biosurfactant–Producing Bacteria with Antimicrobial Activity against Bacterial Pathogens

    Directory of Open Access Journals (Sweden)

    Siripun Sarin

    2011-01-01

    Full Text Available The aims of this research were to study biosurfactant producing bacteria isolated from soil and to determine their property and efficiency as biosurfactants in order to inhibit bacterial pathogens. The result showed that there were 8 bacterial isolates out of 136 isolates of the total biosurfactant producing bacteria screened that exhibited the diameter of clear zone more than 1.5 cm. in the oil spreading test. The highest potential of emulsifying activity (%EA24 of 54.4 and the maximum additive concentration, (%MAC of 24.2 was obtained from the fermentation broth of the G7 isolate which the G7 isolate was later identified as Pseudomonas fluorescens. Escherichia coli, Staphylococcus aureus and Psuedomonas aeruginosa were the tested bacterial pathogens that were most sensitive to the acid precipitated biosurfactant obtained from P. fluorescens G7 with the lowest minimum inhibitory concentration (MIC of 41.6 mg/ml and minimum bactericidal concentration (MBC of 41.6 mg/ml compared with the acid precipitated bisurfactants of the other isolates used in the antimicrobial activity test. The type of the separated crude biosurfactant produced by P. fluorescens G7 analyzed later by using the rhamose test, TLC and FT-IR techniques was rhamnolipid.

  8. Isolation and characterization of novel bacterial strains exhibiting ligninolytic potential

    Directory of Open Access Journals (Sweden)

    Bandounas Luaine

    2011-10-01

    Full Text Available Abstract Background To expand on the range of products which can be obtained from lignocellulosic biomass, the lignin component should be utilized as feedstock for value-added chemicals such as substituted aromatics, instead of being incinerated for heat and energy. Enzymes could provide an effective means for lignin depolymerization into products of interest. In this study, soil bacteria were isolated by enrichment on Kraft lignin and evaluated for their ligninolytic potential as a source of novel enzymes for waste lignin valorization. Results Based on 16S rRNA gene sequencing and phenotypic characterization, the organisms were identified as Pandoraea norimbergensis LD001, Pseudomonas sp LD002 and Bacillus sp LD003. The ligninolytic capability of each of these isolates was assessed by growth on high-molecular weight and low-molecular weight lignin fractions, utilization of lignin-associated aromatic monomers and degradation of ligninolytic indicator dyes. Pandoraea norimbergensis LD001 and Pseudomonas sp. LD002 exhibited best growth on lignin fractions, but limited dye-decolourizing capacity. Bacillus sp. LD003, however, showed least efficient growth on lignin fractions but extensive dye-decolourizing capacity, with a particular preference for the recalcitrant phenothiazine dye class (Azure B, Methylene Blue and Toluidene Blue O. Conclusions Bacillus sp. LD003 was selected as a promising source of novel types of ligninolytic enzymes. Our observations suggested that lignin mineralization and depolymerization are separate events which place additional challenges on the screening of ligninolytic microorganisms for specific ligninolytic enzymes.

  9. A standard bacterial isolate set for research on contemporary dairy spoilage.

    Science.gov (United States)

    Trmčić, A; Martin, N H; Boor, K J; Wiedmann, M

    2015-08-01

    Food spoilage is an ongoing issue that could be dealt with more efficiently if some standardization and unification was introduced in this field of research. For example, research and development efforts to understand and reduce food spoilage can greatly be enhanced through availability and use of standardized isolate sets. To address this critical issue, we have assembled a standard isolate set of dairy spoilers and other selected nonpathogenic organisms frequently associated with dairy products. This publicly available bacterial set consists of (1) 35 gram-positive isolates including 9 Bacillus and 15 Paenibacillus isolates and (2) 16 gram-negative isolates including 4 Pseudomonas and 8 coliform isolates. The set includes isolates obtained from samples of pasteurized milk (n=43), pasteurized chocolate milk (n=1), raw milk (n=1), cheese (n=2), as well as isolates obtained from samples obtained from dairy-powder production (n=4). Analysis of growth characteristics in skim milk broth identified 16 gram-positive and 13 gram-negative isolates as psychrotolerant. Additional phenotypic characterization of isolates included testing for activity of β-galactosidase and lipolytic and proteolytic enzymes. All groups of isolates included in the isolate set exhibited diversity in growth and enzyme activity. Source data for all isolates in this isolate set are publicly available in the FoodMicrobeTracker database (http://www.foodmicrobetracker.com), which allows for continuous updating of information and advancement of knowledge on dairy-spoilage representatives included in this isolate set. This isolate set along with publicly available isolate data provide a unique resource that will help advance knowledge of dairy-spoilage organisms as well as aid industry in development and validation of new control strategies. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Antibiotic resistance among cultured bacterial isolates from bioethanol fermentation facilities across the United States.

    Science.gov (United States)

    Murphree, Colin A; Heist, E Patrick; Moe, Luke A

    2014-09-01

    Bacterial contamination of fuel ethanol fermentations by lactic acid bacteria (LAB) can have crippling effects on bioethanol production. Producers have had success controlling bacterial growth through prophylactic addition of antibiotics to fermentors, yet concerns have arisen about antibiotic resistance among the LAB. Here, we report on mechanisms used by 32 LAB isolates from eight different US bioethanol facilities to persist under conditions of antibiotic stress. Minimum inhibitory concentration assays with penicillin, erythromycin, and virginiamycin revealed broad resistance to each of the antibiotics as well as high levels of resistance to individual antibiotics. Phenotypic assays revealed that antibiotic inactivation mechanisms contributed to the high levels of individual resistances among the isolates, especially to erythromycin and virginiamycin, yet none of the isolates appeared to use a β-lactamase. Biofilm formation was noted among the majority of the isolates and may contribute to persistence under low levels of antibiotics. Nearly all of the isolates carried at least one canonical antibiotic resistance gene and many carried more than one. The erythromycin ribosomal methyltransferase (erm) gene class was found in 19 of 32 isolates, yet a number of these isolates exhibit little to no resistance to erythromycin. The erm genes were present in 15 isolates that encoded more than one antibiotic resistance mechanism, suggestive of potential genetic linkages.

  11. ‘Tidjanibacter massiliensis’ gen. nov., sp. nov., a new bacterial species isolated from human colon

    Directory of Open Access Journals (Sweden)

    M. Mailhe

    2017-05-01

    Full Text Available We report the summary of main characteristics of Tidjanibacter massiliensis strain Marseille-P3084T, a new bacterial species isolated from the liquid sample of the colon of a patient with a history of irritable bowel syndrome.

  12. Antibiotic resistance profile of bacterial isolates from food sold on a ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-02

    Nov 2, 2009 ... Table 1. Distribution and proportion of bacterial contaminants in food. Isolates Identified. Prevalence. E. coli. 23 (29.4%). Klebsiella spp. 20 (25.64%). Proteus spp. 14 (17.95%). Pseudomonas spp. 9 (11.54%). Salmonella spp. 19 (12.82%) analysed from February to July 2005. The food items sampled were.

  13. Bacterial endophytes isolated from plants in natural oil seep soils with chronic hydrocarbon contamination

    Directory of Open Access Journals (Sweden)

    Rhea eLumactud

    2016-05-01

    Full Text Available The bacterial endophytic communities of four plants growing abundantly in soils highly contaminated by hydrocarbons were analyzed through culturable and and culture-independent means. Given their tolerance to the high levels of petroleum contamination at our study site, we sought evidence that Achillea millefolium, Solidago canadensis, Trifolium aureum and Dactylis glomerata support high levels of hydrocarbon degrading endophytes. A total of 190 isolates were isolated from four plant species. The isolates were identified by partial 16S rDNA sequence analysis, with class Actinobacteria as the dominant group in all species except Solidago canadensis, which was dominated by Gammaproteobacteria. Microbacterium foliorum and Plantibacter flavus were present in all the plants, with M. foliorum showing predominance in D. glomerata and both endophytic bacterial species dominated T. aureum. More than 50% of the isolates demonstrated degradative capabilities for octanol, toluene, naphthalene, kerosene or motor oil based on sole carbon source growth screens involving the reduction of tetrazolium dye. P. flavus isolates from all the sampled plants showed growth on all the petroleum hydrocarbons substrates tested. Mineralization of toluene and naphthalene was confirmed using gas-chromatography. 16S based terminal restriction fragment length polymorphism analysis revealed significant differences between the endophytic bacterial communities showing them to be plant host specific at this site. To our knowledge, this is the first account of the degradation potential of bacterial endophytes in these commonly occurring pioneer plants that were not previously known as phytoremediating plants.

  14. Bacterial Isolates from the Urine of Women in Ilorin and their ...

    African Journals Online (AJOL)

    Bacterial Isolates from the Urine of Women in Ilorin and their Antibiotic Susceptibility Patterns. ... Methods: Urine samples of women suspected to have UTI were sent for microscopy, culture and sensitivity tests. The results were analyzed and the differences between the results of pregnant and non-pregnant patients were ...

  15. Endophytic and rhizospheric bacterial communities isolated from the medicinal plants Echinacea purpurea and Echinacea angustifolia.

    Science.gov (United States)

    Chiellini, Carolina; Maida, Isabel; Emiliani, Giovanni; Mengoni, Alessio; Mocali, Stefano; Fabiani, Arturo; Biffi, Sauro; Maggini, Valentina; Gori, Luigi; Vannacci, Alfredo; Gallo, Eugenia; Firenzuoli, Fabio; Fani, Renato

    2014-09-01

    In this work we analyzed the composition and structure of cultivable bacterial communities isolated from the stem/leaf and root compartments of two medicinal plants, Echinacea purpurea (L.) Moench and Echinacea angustifolia (DC.) Hell, grown in the same soil, as well as the bacterial community from their rhizospheric soils. Molecular PCR-based techniques were applied to cultivable bacteria isolated from the three compartments of the two plants. The results showed that the two plants and their respective compartments were characterized by different communities, indicating a low degree of strain sharing and a strong selective pressure within plant tissues. Pseudomonas was the most highly represented genus, together with Actinobacteria and Bacillus spp. The presence of distinct bacterial communities in different plant species and among compartments of the same plant species could account for the differences in the medicinal properties of the two plants. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  16. Isolation and functional characterization of bacterial endophytes from Carica papaya fruits.

    Science.gov (United States)

    Krishnan, P; Bhat, R; Kush, A; Ravikumar, P

    2012-08-01

    To isolate and characterize the endophytes from papaya fruits and to determine the fermentative potential of the strains. Endophytes provide potential sources for novel natural products for the use in agriculture and nutrition. There is very limited information on isolation and characterization of bacterial endophytes from papaya. We describe isolation and characterization of eighteen endophytes of papaya fruit from four economically important papaya varieties viz 'Red lady', 'Solo', 'Coorg Honey' and 'Bangalore'. The phylogenetic analysis based on the 16S rRNA sequence revealed that isolated endophytes are genetically distinct and cluster as discrete clades in the dendrogram. The Bacillus species is a predominant bacterial endophyte across papaya varieties. The seeds and the endocarp of papaya fruits harbour Kocuria, Acinetobacter and Enterobacter species. The Staphylococcus species were detected in the fruit mesocarp of two papaya varieties used in the study. The endophytes isolated from papaya fruits were capable of producing extracellular enzymes like amylase, cellulase, pectinase and xylanase. Three isolates, Bacillus (PE-LR-1 and PE-LR-3) and Kocuria (PE-LR-2), were selected for fruit fermentation, and antioxidant potential of the fermented product was evaluated. PE-LR-3 fermented product has the free radical scavenging activity of 61·2% and a microbial cocktail of PE-LR-3 with Saccharomyces cerevisiae MTCC 2918 enhances the antioxidant potential to 75·7%. These findings suggest that different parts of papaya fruits harbour an array of bacterial endophytes that could be important agents in attributing the high nutritive status to the fruit and can serve as potent microbial cocktails for developing value-added fermented products of this important fruit. This study describes isolation of a bacterial endophyte from papaya fruit that is capable of improving the antioxidant potential of raw papaya after fermentation. No claim to Indian Government works Journal

  17. Isolation and identification of bacterial pathogen from mastitis milk in Central Java Indonesia

    Science.gov (United States)

    Harjanti, D. W.; Ciptaningtyas, R.; Wahyono, F.; Setiatin, ET

    2018-01-01

    Mastitis is a multi-etiologic disease of the mammary gland characterized mainly by reduction in milk production and milk quality due to intramammary infection by pathogenic bacteria. Nearly 83% of lactating dairy cows in Indonesia are infected with mastitis in various inflammation degrees. This study was conducted to isolate and identify the pathogen in milk collected from mastitis-infected dairy cows. The study was carried out in ten smallholder dairy farms in Central Java Indonesia based on animal examination, California mastitis test, isolation bacterial pathogens, Gram staining, Catalase and Coagulase test, and identification of bacteria species using Vitek. Bacteriological examination of milk samples revealed 15 isolates where Streptococcus was predominant species (73.3%) and the coagulase negative Staphylococcus species was identified at the least bacteria (26.7%). The Streptococcus bacteria found were Streptococcus uberis (2 isolates), Streptococcus sanguinis(6 isolates), Streptococcus dysgalactiaessp dysgalactiae(1 isolate) , Streptococcus mitis (1 isolate) and Streptococcus agalactiae (1 isolate). The Staphylococcus isolates comprising of Staphylococcus simulans (1 isolate) and Staphylococcus chromogens (3 isolates). Contamination of raw milkwith pathogenic bacteria can cause outbreaks of human disease (milk borne disease). Thus, proper milk processing method that couldinhibit the growth or kill these pathogenic bacteria is important to ensure the safety of milk and milk products.

  18. Exploration, Isolation, and Identification of Carotenoid from Bacterial Symbiont of Sponge Callyspongia vaginalis

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    Iqna Kamila Abfa

    2017-06-01

    Full Text Available During the past two decades research on marine bacteria has highlighted the tremendous potential of symbiotic-microorganisms as a source of bioactive secondary. One of the potential of the bacterial symbionts is producing a natural pigment, and these organisms can be used as a sustainable source of natural pigments. Carotenoid is one of the most important pigments that has important roles in physiological and molecular processes of microorganisms, as well as for human health. The objective of this study is to analyze carotenoid pigments from marine bacterial symbionts from sponge and to identify bacterial symbionts that produce carotenoid pigments. Pigment analysis was performed by a UV-VIS spectrophotometer and High Performance Liquid Chromatography (HPLC. Molecular bacterial identification was performed based on 16S rDNA sequence. The isolation of bacterial symbionts from C. vaginalison Zobell 2216E medium resulted in one bacterium, CB-SP5, positively synthesized carotenoids. By reverse phase HPLC analysis, the carotenoid pigments in the bacterial symbionts were identified as diadinoxanthin, fucoxanthin, neoxanthin, dinoxanthin, anddiadinochrome. CB-SP5 shared the highest level of 16S rDNA gene sequence similarity with Psychrobacter celer (99%.   Keywords : carotenoid, sponge, bacterial symbiont, 16S rDNA.

  19. Biodegradation of carcinogenic textile azo dyes using bacterial isolates of mangrove sediment

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    Guru Prasad Srinivasan

    2014-02-01

    Full Text Available Objective: To evaluate the biodegrading property against carcinogenic azo dyes using bacterial isolates of mangrove sediment. Methods: The bacterial isolates were subjected to submerged fermentation and their growth kinetics were studied. The potential strain was characterized using 16S rDNA sequencing. Results: In the present study, dye degrading bacterial colonies were isolated from the mangrove sediment samples of Parangipettai estuarine area, Tamil Nadu. Of the 30 morphologically different strains isolated, 5 showed antagonistic property. The growth kinetics of the two strains, P1 and G1, which showed potent activity were calculated. One particular isolate (P1 showing promising dye degrading potential in the submerged fermentation was further characterized. The strain was identified as Paenibacillus sp. by 16S rDNA sequencing. Conclusions: This study reveals the less explored microflora of mangrove sediments. The novel strain may further be analyzed and used in the treatment of effluent from dye industry so as to reduce the impact of carcinogenic contaminants.

  20. Trends of Bacterial Keratitis Culture Isolates in Jerusalem; a 13- Years Analysis.

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    Michael Politis

    Full Text Available To describe the trends in pathogens and antibacterial resistance of corneal culture isolates in infectious keratitis during a period of 13 years at Hadassah-Hebrew University Medical Center.A Retrospective analysis of bacterial corneal isolates was performed during the months of January 2002 to December 2014 at Hadassah Hebrew University Medical Center. Demographics, microbiological data and antibiotic resistance and sensitivity were collected.A total of 943 corneal isolates were analyzed during a 13 year period. A total of 415 positive bacterial cultures and 37 positive fungal cultures were recovered, representing 48% of the total cultures. The Annual incidence was 34.78 ± 6.54 cases. The most common isolate was coagulase-negative staphylococcus (32%, which had a significant decrease in trend throughout the study period (APC = -8.1, p = 0.002. Methicillin-resistant Staphylococcus aureus (MRSA appears to have a decrease trend (APC = -31.2, P = 0.5. There was an increase in the resistance trend of coagulase-negative staphylococci to penicillin (APC = 5.0, P = <0.001. None of the pathogens had developed any resistance to Vancomycin. (P = 0.88.Coagulase negative staphylococci were the predominant bacteria isolated from patients with keratitis. There was no significant change in the annual incidence of cases of bacterial keratitis seen over the past 13 years. Keratitis caused by MRSA appeared to decrease in contrast to the reported literature.

  1. Biodegradation of Ochratoxin A by Bacterial Strains Isolated from Vineyard Soils

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    Palmira De Bellis

    2015-11-01

    Full Text Available Ochratoxin A (OTA is a mycotoxin with a main nephrotoxic activity contaminating several foodstuffs. In the present report, five soil samples collected from OTA-contaminated vineyards were screened to isolate microorganisms able to biodegrade OTA. When cultivated in OTA-supplemented medium, OTA was converted in OTα by 225 bacterial isolates. To reveal clonal relationships between isolates, molecular typing by using an automated rep-PCR system was carried out, thus showing the presence of 27 different strains (rep-PCR profiles. The 16S-rRNA gene sequence analysis of an isolate representative of each rep-PCR profiles indicated that they belonged to five bacterial genera, namely Pseudomonas, Leclercia, Pantoea, Enterobacter, and Acinetobacter. However, further evaluation of OTA-degrading activity by the 27 strains revealed that only Acinetobacter calcoaceticus strain 396.1 and Acinetobacter sp. strain neg1, consistently conserved the above property; their further characterization showed that they were able to convert 82% and 91% OTA into OTα in six days at 24 °C, respectively. The presence of OTα, as the unique OTA-degradation product was confirmed by LC-HRMS. This is the first report on OTA biodegradation by bacterial strains isolated from agricultural soils and carried out under aerobic conditions and moderate temperatures. These microorganisms might be used to detoxify OTA-contaminated feed and could be a new source of gene(s for the development of a novel enzymatic detoxification system.

  2. Isolation and identification of bacterial causes of clinical mastitis in cattle in Sulaimania region

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    S. A. Hussein

    2008-01-01

    Full Text Available A total of 51 cases of bovine clinical mastitis in Sulaimani district were investigated for their bacteriological causative agents; 76 milk samples were cultured on primary and selective media and the isolated bacteria were tested for their susceptibility to antimicrobial agents used in commercial intramammary infusion products. Eighty two bacterial isolates were obtained and further identified using biochemical tests. Escherichia coli was the most common bacteria followed by Staphylococcus aureus, Streptococcus agalactia and coagulase–negative staphylococci. Two other bacterial species (Pseudomonas aeruginosa and Streptococcucs uberis were also isolated but in a lower proportion. Antibacterial susceptibility testing showed that the use of florfenicol, cephalexin and gentamicin may be useful for the treatment of clinical mastitis cases in cows.

  3. Aislamientos bacterianos de muestras respiratorias de pacientes pediátricos con fibrosis quística y su distribución por edades Bacterial isolates from respiratory samples of pediatric patients with cystic fibrosis and their distribution by ages

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    Natalia P Busquets

    2013-03-01

    Full Text Available Se investigaron los microorganismos aislados de muestras respiratorias de 50 pacientes pediátricos con fibrosis quística. Se analizó la distribución por edades y se examinó la resistencia a los antimicrobianos, la intermitencia de los aislamientos y la presencia de coinfecciones. Se aisló Staphylococcus aureus en el 72 % de los pacientes, seguido de Pseudomonas aeruginosa (58 %, Haemophilus influenzae (56 % y complejo Burkholderia cepacia (12 %. Encontramos baja frecuencia de aislamientos de P. aeruginosa resistentes a los antibióticos p-lactámicos (13,8 %. El 50,0 % de S. aureus fue resistente a la meticilina. El 57,1 % de H. influenzae fue resistente a la ampicilina por producción de ß-lactamasa. En niños menores de 4 años predominó S. aureus, seguido de P. aeruginosa y H. influenzae. Este orden se observó en todos los grupos etarios analizados, excepto en el de los niños de 10 a 14 años. Los aislamientos de Stenotrophomonas maltophilia y Achromobacter xylosoxidans fueron intermitentes y estuvieron acompañados por otros microorganismos. En suma, en este estudio observamos una gran variedad de especies bacterianas, lo que impone la necesidad de realizar rigurosos estudios microbiológicos en los materiales respiratorios de estos pacientes.The bacterial isolates from respiratory samples of 50 pediatric patients with cystic fibrosis, their distribution by ages and antimicrobial resistance pattern as well as the intermittence of isolations and coinfections, were investigated. Staphylococcus aureus was isolated in 72 % of patients, followed by Pseudomonas aeruginosa (58 %, Haemophilus. influenzae (56 %, and the Burkholderia cepacia complex (12 %. The frequency of resistance of P. aeruginosa isolates to ß-lactam antibiotics was low (13.8 %. Fifty percent of S. aureus isolates was methicillin-resistant, and 57.1 % of H. influenza was ampicillin-resistant due to ß-lactamase production. In children under 4 years-old, S. aureus was

  4. Genotypic and Phenotypic Characterization of Stenotrophomonas maltophilia Strains from a Pediatric Tertiary Care Hospital in Serbia.

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    Haowa Madi

    Full Text Available Stenotrophomonas maltophilia is an environmental bacterium and an opportunistic pathogen usually associated with healthcare-associated infections, which has recently been recognized as a globally multi-drug resistant organism. The aim of this study was genotyping and physiological characterization of Stenotrophomonas maltophilia isolated in a large, tertiary care pediatric hospital in Belgrade, Serbia, hosting the national reference cystic fibrosis (CF center for pediatric and adult patients.We characterized 42 strains of cystic fibrosis (CF and 46 strains of non-cystic fibrosis (non-CF origin isolated from 2013 to 2015 in order to investigate their genetic relatedness and phenotypic traits. Genotyping was performed using sequencing of 16S rRNA gene, Pulse Field Gel Electrophoresis (PFGE and Multi locus sequencing typing (MLST analysis. Sensitivity to five relevant antimicrobial agents was determined, namely trimethoprim/sulfamethoxazole (TMP/SMX, chloramphenicol, ciprofloxacin, levofloxacin and tetracycline. Surface characteristics, motility, biofilm formation and adhesion to mucin were tested in all strains. Statistical approach was used to determine correlations between obtained results.Most of the isolates were not genetically related. Six new sequence types were determined. Strains were uniformly sensitive to all tested antimicrobial agents. The majority of isolates (89.8% were able to form biofilm with almost equal representation in both CF and non-CF strains. Swimming motility was observed in all strains, while none of them exhibited swarming motility. Among strains able to adhere to mucin, no differences between CF and non-CF isolates were observed.High genetic diversity among isolates implies the absence of clonal spread within the hospital. Positive correlation between motility, biofilm formation and adhesion to mucin was demonstrated. Biofilm formation and motility were more pronounced among non-CF than CF isolates.

  5. Inhibitory Effect of Lactobacillus reuteri on Some Pathogenic Bacteria Isolated From Women With Bacterial Vaginosis

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    Eslami

    2014-08-01

    Full Text Available Background Considering the high prevalence of bacterial vaginosis and its association with urinary tract infection in women and treatment of gynecologic problems occur when a high recurrence of bacterial vaginosis is often treated with antibiotics. Objectives The purpose of this study was to investigate the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria isolated from women with bacterial vaginosis. Materials and Methods Ninety-six samples were obtained from vaginal discharge of women with bacterial vaginosis by a gynecologist with a Dacron swab and put in sterile tubes containing TSB broth and Thioglycollate broth. Then were immediately sent to the laboratory in cold chain for further assessment. Afterward, culture was transferred on blood agar, EMB, Palcam and differential diagnosis environments. Then cultures were incubated for 24 hours at 37 °C. Lactobacillus reuteri strains were cultured in MRS environment and transferred to laboratory. After purification of pathogenic bacteria, Lactobacillus reuteri inhibitory effect on pathogenic bacteria was evaluated by minimum inhibitory concentration (MIC and antibiogram. Statistical analysis was performed using SPSS software v.16. Results The results of this study demonstrated the inhibitory effect of Lactobacillus reuteri on some pathogenic bacteria that cause bacterial, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus agalactiae, Enterococcus, Listeria monocytogenes and E. coli. Microscopic examination of stained smears of most Lactobacillus and pathogenic bacteria showed reduced. The prevalence of abnormal vaginal discharge, history of drug use, contraceptive methods and douching were 61%, 55%, 42% and 13%, respectively. Significant difference was observed between the use and non-use of IUD in women with bacterial. Conclusions Our findings indicated the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria that

  6. In-vitro efficacy of antibacterials against bacterial isolates from corneal ulcers.

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    Bharathi Jayahar

    2002-01-01

    Full Text Available PURPOSE: To analyse the in-vitro efficacy of commonly used antibacterials against bacterial pathogens from corneal ulcers. METHODS: We evaluated 596 patients seen over 18 months, period, September 1999 through March 2001. Corneal scrapings were subjected to microscopy and cultures using standard protocols. Antibacterial susceptibility of isolated bacteria were determined by the Kirby-Bauer disc-diffusion method. RESULTS: 626 bacterial pathogens were isolated from 596 corneal ulcer cases. 411(65.65% were gram positive cocci Streptococcus pneumoniae (41.85% was the predominant bacterial species. The antibacterial susceptibility was: 451(72.04% to cefazolin, 471(75.24% to chloramphenicol; 321(51.28% to cephaloridine; 430(68.69% to vancomycin; 564(90.09% to ciprofloxacin; 429(68.53% to norfloxacin; 464(74.12% to gentamicin and 202(32.27% to co.trimoxazole. CONCLUSION: This study provides information on the efficacy of ocular antibacterials commonly used against bacterial pathogens of keratitis. It is hoped that this information will help decision-making in empiric initial treatment of bacterial keratitis.

  7. Novel bacterial consortia isolated from plastic garbage processing areas demonstrated enhanced degradation for low density polyethylene.

    Science.gov (United States)

    Skariyachan, Sinosh; Manjunatha, Vishal; Sultana, Subiya; Jois, Chandana; Bai, Vidya; Vasist, Kiran S

    2016-09-01

    This study aimed to formulate novel microbial consortia isolated from plastic garbage processing areas and thereby devise an eco-friendly approach for enhanced degradation of low-density polyethylene (LDPE). The LDPE degrading bacteria were screened and microbiologically characterized. The best isolates were formulated as bacterial consortia, and degradation efficiency was compared with the consortia formulated using known isolates obtained from the Microbial Culture Collection Centre (MTCC). The degradation products were analyzed by FTIR, GC-FID, tensile strength, and SEM. The bacterial consortia were characterized by 16S ribosomal DNA (rDNA) sequencing. The formulated bacterial consortia demonstrated 81 ± 4 and 38 ± 3 % of weight reduction for LDPE strips and LDPE pellets, respectively, over a period of 120 days. However, the consortia formulated by MTCC strains demonstrated 49 ± 4 and 20 ± 2 % of weight reduction for LDPE strips and pellets, respectively, for the same period. Furthermore, the three isolates in its individual application exhibited 70 ± 4, 68 ± 4, and 64 ± 4 % weight reduction for LDPE strips and 21 ± 2, 28 ± 2, 24 ± 2 % weight reduction for LDPE pellets over a period of 120 days (p waste management of LDPE and similar types of plastic garbage.

  8. Trends of Bacterial Keratitis Culture Isolates in Jerusalem; a 13- Years Analysis

    Science.gov (United States)

    Politis, Michael; Wajnsztajn, Denise; Rosin, Boris; Block, Colin; Solomon, Abraham

    2016-01-01

    Purpose To describe the trends in pathogens and antibacterial resistance of corneal culture isolates in infectious keratitis during a period of 13 years at Hadassah-Hebrew University Medical Center. Methods A Retrospective analysis of bacterial corneal isolates was performed during the months of January 2002 to December 2014 at Hadassah Hebrew University Medical Center. Demographics, microbiological data and antibiotic resistance and sensitivity were collected. Results A total of 943 corneal isolates were analyzed during a 13 year period. A total of 415 positive bacterial cultures and 37 positive fungal cultures were recovered, representing 48% of the total cultures. The Annual incidence was 34.78 ± 6.54 cases. The most common isolate was coagulase-negative staphylococcus (32%), which had a significant decrease in trend throughout the study period (APC = -8.1, p = 0.002). Methicillin-resistant Staphylococcus aureus (MRSA) appears to have a decrease trend (APC = -31.2, P = 0.5). There was an increase in the resistance trend of coagulase-negative staphylococci to penicillin (APC = 5.0, P = keratitis. There was no significant change in the annual incidence of cases of bacterial keratitis seen over the past 13 years. Keratitis caused by MRSA appeared to decrease in contrast to the reported literature. PMID:27893743

  9. Initial nitrogen enrichment conditions determines variations in nitrogen substrate utilization by heterotrophic bacterial isolates.

    Science.gov (United States)

    Ghosh, Suchismita; Ayayee, Paul A; Valverde-Barrantes, Oscar J; Blackwood, Christopher B; Royer, Todd V; Leff, Laura G

    2017-04-04

    The nitrogen (N) cycle consists of complex microbe-mediated transformations driven by a variety of factors, including diversity and concentrations of N compounds. In this study, we examined taxonomic diversity and N substrate utilization by heterotrophic bacteria isolated from streams under complex and simple N-enrichment conditions. Diversity estimates differed among isolates from the enrichments, but no significant composition were detected. Substrate utilization and substrate range of bacterial assemblages differed within and among enrichments types, and not simply between simple and complex N-enrichments. N substrate use patterns differed between isolates from some complex and simple N-enrichments while others were unexpectedly similar. Taxonomic composition of isolates did not differ among enrichments and was unrelated to N use suggesting strong functional redundancy. Ultimately, our results imply that the available N pool influences physiology and selects for bacteria with various abilities that are unrelated to their taxonomic affiliation.

  10. Label-free isolation and deposition of single bacterial cells from heterogeneous samples for clonal culturing

    OpenAIRE

    J. Riba; T. Gleichmann; S. Zimmermann; R. Zengerle; P. Koltay

    2016-01-01

    The isolation and analysis of single prokaryotic cells down to 1??m and less in size poses a special challenge and requires micro-engineered devices to handle volumes in the picoliter to nanoliter range. Here, an advanced Single-Cell Printer (SCP) was applied for automated and label-free isolation and deposition of bacterial cells encapsulated in 35?pl droplets by inkjet-like printing. To achieve this, dispenser chips to generate micro droplets have been fabricated with nozzles 20??m in size....

  11. Bacterial isolates from burn wound infections and their antibiograms: A eight-year study

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    Mehta Manjula

    2007-01-01

    Full Text Available Background: Infection is an important cause of mortality in burns. Rapidly emerging nosocomial pathogens and the problem of multi-drug resistance necessitates periodic review of isolation patterns and antibiogram in the burn ward. Aim: Keeping this in mind, the present retrospective study from wounds of patients admitted to burns unit was undertaken to determine the bacteriological profile and the resistance pattern from the burn ward over a period of three years (June 2002 to May 2005 and was compared with the results obtained during the previous five years (June 1997-May 2002, to ascertain any change in the bacteriological profile and antimicrobial resistance pattern. Materials and Methods: Bacterial isolates from 268 wound swabs taken from burn patients were identified by conventional biochemical methods and antimicrobial susceptibility was performed. Statistical comparison of bacterial isolates and their resistance pattern with previous five years data was done using c2 test. Results and Conclusions: During the period from 2002 to 2005 Pseudomonas species was the commonest pathogen isolated (51.5% followed by Acinetobacter species (14.28%, Staph. aureus (11.15%, Klebsiella species (9.23% and Proteus species (2.3%. When compared with the results of the previous five years i.e., 1997 to 2002, Pseudomonas species was still the commonest pathogen in the burns unit. However, the isolation of this organism and other gram-negative organisms had decreased in comparison to previous years. Newer drugs were found to be effective.

  12. Changes In Protein Abundance Are Observed In Bacterial Isolates from a Natural Host

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    Megan Anne Rees

    2015-10-01

    Full Text Available Bacterial proteomic studies frequently use strains cultured in synthetic liquid media over many generations. It is uncertain whether bacterial proteins expressed under these conditions will be the same as the repertoire found in natural environments, or when bacteria are infecting a host organism. Thus, genomic and proteomic characterisation of bacteria derived from the host environment in comparison to reference strains grown in the lab, should aid understanding of pathogenesis. Isolates of Corynebacterium pseudotuberculosis were obtained from the nodes of three naturally infected sheep and compared to a laboratory reference strain using bottom-up proteomics, after whole genome sequencing of each of the field isolates. These comparisons were performed following growth in liquid media that allowed us to reach the required protein amount for proteomic analysis. Over 1350 proteins identified in the isolated strains, from which unique proteome features were revealed. Several of the identified proteins demonstrated a significant abundance difference in the field isolates compared to the reference strain even though there were no obvious differences in the DNA sequence of the corresponding gene or in nearby non-coding DNA. Higher abundance in the field isolates was observed for proteins related to hypoxia and nutrient deficiency responses as well as to thiopeptide biosynthesis.

  13. Changes in protein abundance are observed in bacterial isolates from a natural host.

    Science.gov (United States)

    Rees, Megan A; Stinear, Timothy P; Goode, Robert J A; Coppel, Ross L; Smith, Alexander I; Kleifeld, Oded

    2015-01-01

    Bacterial proteomic studies frequently use strains cultured in synthetic liquid media over many generations. It is uncertain whether bacterial proteins expressed under these conditions will be the same as the repertoire found in natural environments, or when bacteria are infecting a host organism. Thus, genomic and proteomic characterization of bacteria derived from the host environment in comparison to reference strains grown in the lab, should aid understanding of pathogenesis. Isolates of Corynebacterium pseudotuberculosis were obtained from the lymph nodes of three naturally infected sheep and compared to a laboratory reference strain using bottom-up proteomics, after whole genome sequencing of each of the field isolates. These comparisons were performed following growth in liquid media that allowed us to reach the required protein amount for proteomic analysis. Over 1350 proteins were identified in the isolated strains, from which unique proteome features were revealed. Several of the identified proteins demonstrated a significant abundance difference in the field isolates compared to the reference strain even though there were no obvious differences in the DNA sequence of the corresponding gene or in nearby non-coding DNA. Higher abundance in the field isolates was observed for proteins related to hypoxia and nutrient deficiency responses as well as to thiopeptide biosynthesis.

  14. 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)

  15. MICROBIAL PROFILE AND ANTIBIOTIC RESISTANCE PATTERN OF THE BACTERIAL ISOLATES IN A TERTIARY CARE PSYCHIATRY HOSPITAL

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    Jyoti

    2015-11-01

    Full Text Available BACKGROUND: Antibiotic resistance is a challenge for effective management of infections as it increases the morbidity, mortality and costs of treating infectious diseases. AIMS: This study was aimed to obtain the profile of the bacterial isolates and their antibiotic resistance pattern. SETTINGS AND DESIGN: It is a cross sectional study carried out in a tertiary care psychiatry hospital in India. MATERIALS AND METHODS: Isolation and identification of the isolates were done by standard methods. Susceptibility patterns were checked by Kirby Bauer disc diffusion method. STATISTICAL ANALYSIS USED: Statistical analysis was done by using SPSS 16.0 version to calculate the frequencies as well as for cross tabulation. RESULTS: Significant bacterial growth observed in 43(25.6% samples, of which 39(90.7% showed resistant to at least one of the antibiotics used and 36(83.7% were multi-drug resistant. Gram negative organism accounted for the 25(58.14% of total significant isolates, Escherichia coli being the highest (76% in this group. Among multi-drug resistant (MDR isolates E.coli was the highest (44.4% and imipenem resistance was also observed in 1(5.3% of 19 E.coli isolates. Among the 43 isolates 18(41.86% were Gram positive with Streptococcus spp. showing incidence of 41.7% among the total MDR isolates. CONCLUSION: Increasing incidence of MDR strains seen in the population requires continuous monitoring and a restricted use of antibiotics to keep a check on resistance pattern, for effective treatment plan.

  16. Culturable bacterial endophytes isolated from Mangrove tree (Rhizophora apiculata Blume) enhance seedling growth in Rice.

    Science.gov (United States)

    Deivanai, Subramanian; Bindusara, Amitraghata Santhanam; Prabhakaran, Guruswamy; Bhore, Subhash Janardhan

    2014-07-01

    Endophytic bacteria do have several potential applications in medicine and in other various sectors of biotechnology including agriculture. Bacterial endophytes need to be explored for their potential applications in agricultural biotechnology. One of the potential applications of bacterial endophytes in agricultural is to enhance the growth of the agricultural crops. Hence, this study was undertaken to explore the plant growth promoting potential application of bacterial endophytes. The objective of this study was to examine the effect of endophytic bacteria from mangrove tree (Rhizophora apiculata Blume) for their efficacy in promoting seedling growth in rice. Eight endophytic bacterial isolates (EBIs) isolated from twig and petiole tissues of the mangrove were identified based on their 16S ribosomal ribonucleic acid (rRNA) gene sequence homology. Separately, surface sterilized paddy seeds were treated with cell-free broth and cell suspension of the EBIs. Rice seedlings were analyzed by various bioassays and data was recorded. The gene sequences of the isolates were closely related to two genera namely, Bacillus and Pantoea. Inoculation of EBIs from R. apiculata with rice seeds resulted in accelerated root and shoot growth with significant increase in chlorophyll content. Among the isolates, Pantoea ananatis (1MSE1) and Bacillus amyloliquefaciens (3MPE1) had shown predominance of activity. Endophytic invasion was recognized by the non-host by rapid accumulation of reactive oxygen species (ROS) and was counteracted by the production of hydrogen peroxide (H2O2) and lipid peroxide. The results demonstrated that EBIs from mangrove tree can increase the fitness of the rice seedlings under controlled conditions. These research findings could be useful to enhance the seedling growth and could serve as foundation in further research on enhancing the growth of the rice crop using endophytic bacteria.

  17. Assessment of biofilm formation in device-associated clinical bacterial isolates in a tertiary level hospital

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    Summaiya A Mulla

    2011-01-01

    Full Text Available Background: Biofilm formation is a developmental process with intercellular signals that regulate growth. Biofilms contaminate catheters, ventilators, and medical implants; they act as a source of disease for humans, animals, and plants. Aim: In this study we have done quantitative assessment of biofilm formation in device-associated clinical bacterial isolates in response to various concentrations of glucose in tryptic soya broth and with different incubation time. Materials and Methods: The study was carried out on 100 positive bacteriological cultures of medical devices, which were inserted in hospitalized patients. The bacterial isolates were processed as per microtitre plate method with tryptic soya broth alone and with varying concentrations of glucose and were observed in response to time. Results: Majority of catheter cultures were positive. Out of the total 100 bacterial isolates tested, 88 of them were biofilm formers. Incubation period of 16-20 h was found to be optimum for biofilm development. Conclusions: Availability of nutrition in the form of glucose enhances the biofilm formation by bacteria. Biofilm formation depends on adherence of bacteria to various surfaces. Time and availability of glucose are important factors for assessment of biofilm progress.

  18. General and specialized media routinely employed for primary isolation of bacterial pathogens of fishes

    Science.gov (United States)

    Starliper, C.E.

    2008-01-01

    There are a number of significant diseases among cultured and free-ranging freshwater fishes that have a bacterial etiology; these represent a variety of gram-negative and gram-positive genera. Confirmatory diagnosis of these diseases involves primary isolation of the causative bacterium on bacteriologic media. Frequently used "general" bacteriologic media simply provide the essential nutrients for growth. For most of the major pathogens, however, there are differential and/or selective media that facilitate primary recovery. Some specialized media are available as "ready-to-use" from suppliers, while others must be prepared. Differential media employ various types of indicator systems, such as pH indicators, that allow diagnosticians to observe assimilation of selected substrates. An advantage to the use of differential media for primary isolation is that they hasten bacterial characterization by yielding the appropriate positive or negative result for a particular substrate, often leading to a presumptive identification. Selective media also incorporate agent(s) that inhibit the growth of contaminants typically encountered with samples from aquatic environments. Media that incorporate differential and/or selective components are ideally based on characters that are unique to the targeted bacterium, and their use can reduce the time associated with diagnosis and facilitate early intervention in affected fish populations. In this review, the concepts of general and differential/selective bacteriologic media and their use and development for fish pathogens are discussed. The media routinely employed for primary isolation of the significant bacterial pathogens of fishes are presented. ?? Wildlife Disease Association 2008.

  19. Characterization of CCN and IN activity of bacterial isolates collected in Atlanta, GA

    Science.gov (United States)

    Purdue, Sara; Waters, Samantha; Karthikeyan, Smruthi; Konstantinidis, Kostas; Nenes, Athanasios

    2016-04-01

    Characterization of CCN activity of bacteria, other than a few select types such as Pseudomonas syringae, is limited, especially when looked at in conjunction with corresponding IN activity. The link between these two points is especially important for bacteria as those that have high CCN activity are likely to form an aqueous phase required for immersion freezing. Given the high ice nucleation temperature of bacterial cells, especially in immersion mode, it is important to characterize the CCN and IN activity of many different bacterial strains. To this effect, we developed a droplet freezing assay (DFA) which consists of an aluminum cold plate, cooled by a continuous flow of an ethylene glycol-water mixture, in order to observe immersion freezing of the collected bacteria. Here, we present the initial results on the CCN and IN activities of bacterial samples we have collected in Atlanta, GA. Bacterial strains were collected and isolated from rainwater samples taken from different storms throughout the year. We then characterized the CCN activity of each strain using a DMT Continuous Flow Streamwise Thermal Gradient CCN Counter by exposing the aerosolized bacteria to supersaturations ranging from 0.05% to 0.6%. Additionally, using our new DFA, we characterized the IN activity of each bacterial strain at temperatures ranging from -20oC to 0oC. The combined CCN and IN activity gives us valuable information on how some uncharacterized bacteria contribute to warm and mixed-phase cloud formation in the atmosphere.

  20. Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

    Science.gov (United States)

    Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

    2016-02-01

    We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

  1. A molecular biological protocol to distinguish potentially human pathogenic Stenotrophomonas maltophilia from plant-associated Stenotrophomonas rhizophila.

    Science.gov (United States)

    Ribbeck-Busch, Kathrin; Roder, Anja; Hasse, Dirk; de Boer, Wietse; Martínez, José Luis; Hagemann, Martin; Berg, Gabriele

    2005-11-01

    In recent years, the importance of the Gram-negative bacterium Stenotrophomonas as an opportunistic pathogen as well as in biotechnology has increased. The aim of the present study was to develop new methods for distinguishing between strains closely related to the potentially human pathogenic Stenotrophomonas maltophilia and those closely related to the plant-associated Stenotrophomonas rhizophila. To accomplish this, 58 strains were characterized by 16S rDNA sequencing and amplified ribosomal DNA restriction analysis (ARDRA), and the occurrence of specific functional genes. Based on 16S rDNA sequences, an ARDRA protocol was developed which allowed differentiation between strains of the S. maltophilia and the S. rhizophila group. As it was known that only salt-treated cells of S. rhizophila were able to synthesize the compatible solute glucosylglycerol (GG), the ggpS gene responsible for GG synthesis was used for differentiation between both species and it was confirmed that it only occurred in S. rhizophila strains. As a further genetic marker the smeD gene, which is part of the genes coding for the multidrug efflux pump SmeDEF from S. maltophilia, was used. Based on the results we propose a combination of fingerprinting techniques using the 16S rDNA and the functional genes ggpS and smeD to distinguish both Stenotrophomonas species.

  2. A molecular biological protocol to distinguish potentially human pathogenic Stenotrophomonas maltophilia from plant-associated Stenotrophomonas rhizophila

    NARCIS (Netherlands)

    Ribbeck-Busch, K.; Roder, A.; Hasse, D.; De Boer, W.; Martinez, J.L.; Hagemann, M.; Berg, G.

    2005-01-01

    In recent years, the importance of the Gram-negative bacterium Stenotrophomonas as an opportunistic pathogen as well as in biotechnology has increased. The aim of the present study was to develop new methods for distinguishing between strains closely related to the potentially human pathogenic

  3. COMPARATIVE EVALUATION OF CULTURE MEDIA FOR PATHOGEN ISOLATION OF PURULENT BACTERIAL MENINGITIS

    Directory of Open Access Journals (Sweden)

    Ya. V. Podkopaev

    2016-01-01

    Full Text Available The State Research Center for Applied Microbiology and Biotechnology has designed two nutrient media — chocolate agar and PBM-agar to isolate pathogens of purulent bacterial meningitis (PBM. In our previous research using collected microbial strains the media were shown to be highly susceptible and to provide the growth of Neisseria meningiti-dis, Streptococcus pneumoniae and Haemophilus influenzae strains, when inoculated with microbial suspensions containing single cells. When isolating Haemophilus influenzae, meningococci, and pneumococci the use of selective additives in both media assures selective isolation of required microorganisms, inhibiting contaminants. The objective of this research was to assess the media in bacteriological tests of clinical samples collected from the upper and lower respiratory tract in humans. The bacteriological plating of throat smear specimens (n = 90 from children and adults at the age of 0 to 66 with disorder of the upper respiratory tract on chocolate agar, PBM-agar and on a control medium in the absence of selective additives resulted in the equal amount of microbial cultures isolated. Of 154 isolated cultures 2, 23 and 9 were attributed to Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae, respectively. The plating of throat smears (n = 10 from healthy people at the age of 30 to 55 on the analyzable and control media in the presence of additives allowed us to selectively isolate Haemophilus influenzae and Streptococcus pneumoniae cultures without a quantitative loss, with contaminants inhibited. By their growth characteristics chocolate agar and PBM-agar were highly competitive with reference media being used in clinical practice for isolating main causative agents of purulent bacterial meningitis.

  4. Proteolysis produced within biofilms of bacterial isolates from raw milk tankers.

    Science.gov (United States)

    Teh, Koon Hoong; Flint, Steve; Palmer, Jon; Andrewes, Paul; Bremer, Phil; Lindsay, Denise

    2012-06-15

    In this study, six bacterial isolates that produced thermo-resistant enzymes isolated from the internal surfaces of raw milk tankers were evaluated for their ability to produce proteolysis within either single culture biofilms or co-culture biofilms. Biofilms were formed in an in vitro model system that simulated the upper internal surface of a raw milk tanker during a typical summer's day of milk collection in New Zealand. The bacterial isolates were further evaluated for their ability to form biofilms at 25, 30 and 37°C. Mutual and competitive effects were observed in some of the co-culture biofilms, with all isolates being able to form biofilms in either single culture or co-culture at the three temperatures. The proteolysis was also evaluated in both biofilms and corresponding planktonic cultures. The proteolysis per cell decreased as the temperature of incubation (20-37°C) increased. Furthermore, mutualistic interactions in terms of proteolysis were observed when cultures were grown as co-culture biofilms. This is the first study to show that proteolytic enzymes can be produced in biofilms on the internal surfaces of raw milk tankers. This has important implications for the cleaning and the temperature control of raw milk transport tankers. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Biodegradation of fenvalerate and 3-phenoxybenzoic acid by a novel Stenotrophomonas sp. strain ZS-S-01 and its use in bioremediation of contaminated soils.

    Science.gov (United States)

    Chen, Shaohua; Yang, Liu; Hu, Meiying; Liu, Jingjing

    2011-04-01

    A bacterial strain ZS-S-01, newly isolated from activated sludge, could effectively degrade fenvalerate and its hydrolysis product 3-phenoxybenzoic acid (3-PBA). Based on the morphology, physiological biochemical characteristics, and 16 S rDNA sequence, strain ZS-S-01 was identified as Stenotrophomonas sp. Strain ZS-S-01 could also degrade and utilize deltamethrin, beta-cypermethrin, beta-cyfluthrin, and cyhalothrin as substrates for growth. Strain ZS-S-01 was capable of degrading fenvalerate rapidly without a lag phase over a wide range of pH and temperature, even in the presence of other carbon sources, and metabolized it to yield 3-PBA, then completely degraded it. No persistent accumulative product was detected by HPLC and GC/MS analysis. Studies on biodegradation in various soils showed that strain ZS-S-01 demonstrated efficient degradation of fenvalerate and 3-PBA (both 50 mg·kg(-1)) with a rate constant of 0.1418-0.3073 d(-1), and half-lives ranged from 2.3 to 4.9 days. Compared with the controls, the half-lives for fenvalerate and 3-PBA reduced by 16.9-156.3 days. These results highlight strain ZS-S-01 may have potential for use in bioremediation of pyrethroid-contaminated environment. © Springer-Verlag 2010

  6. ‘Colibacter massiliensis’ gen. nov., sp. nov., a new bacterial species isolated from human left colon

    Directory of Open Access Journals (Sweden)

    M. Mailhe

    2017-05-01

    Full Text Available We present here the main characteristics of the strain Marseille-P2911 (= CSUR P2911=DSMZ 103304, a bacterial species isolated from the left colon liquid sample of a 60-year-old man.

  7. Chlorhexidine Digluconate Effects on Planktonic Growth and Biofilm Formation in Some Field Isolates of Animal Bacterial Pathogens

    Science.gov (United States)

    Ebrahimi, Azizollah; Hemati, Majid; Habibian Dehkordi, Saeed; Bahadoran, Shahab; Khoshnood, Sheida; Khubani, Shahin; Dokht Faraj, Mahdi; Hakimi Alni, Reza

    2014-01-01

    Background: To study chlorhexidine digluconate disinfectant effects on planktonic growth and biofilm formation in some bacterial field isolates from animals. Objectives: The current study investigated chlorhexidine digluconate effects on planktonic growth and biofilm formation in some field isolates of veterinary bacterial pathogens. Materials and Methods: Forty clinical isolates of Escherichia coli, Salmonella serotypes, Staphylococcus. aureus and Streptococcus agalactiae (10 isolates for each) were examined for chlorhexidine digluconate effects on biofilm formation and planktonic growth using microtiter plates. In all of the examined strains in the presence of chlorhexidine digluconate, biofilm development and planktonic growth were affected at the same concentrations of the disinfectant. Results: Chlorhexidine digluconate inhibited the planktonic growth of different bacterial species at sub-MICs. But they were able to induce biofilm development of the E. coli, Salmonella spp., S. aureus and Str. agalactiae strains. Conclusions: Bacterial resistance against chlorhexidine is increasing. Sub-MIC doses of chlorhexidine digluconate can stimulate the formation of biofilm strains. PMID:24872940

  8. Plant growth-promoting activities for bacterial and fungal endophytes isolated from medicinal plant of Teucrium polium L.

    OpenAIRE

    Hassan, Saad El-Din

    2017-01-01

    Bacterial and fungal endophytes are widespread inhabitants inside plant tissues and have been shown to assist plant growth and health. However, little is known about plant growth-promoting endophytes (PGPE) of medicinal plants. Therefore, the aims of this study were to identify bacterial and fungal endophytes of Teucrium polium and to characterize plant growth-promoting (PGP) properties of these endophytes. Seven bacterial endophytes were isolated and identified as Bacillus cereus and Bacillu...

  9. Inhibitory effect of Lactobacillus rhamnosus on pathogenic bacteria isolated from women with bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    Gita Eslami

    2014-06-01

    Full Text Available Background: Considering the high prevalence of bacterial vaginosis and its association with urinary tract infection in women and treatment of gynecologic problems occur when a high recurrence of bacterial vaginosis is often treated with antibiotics. The purpose of this study is to investigate the inhibitory effect of Lactobacillus rhamnosus on pathogenic bacteria isolated from women with bacterial vaginosis, respectively.Materials and Methods: 96 samples from women with bacterial vaginosis discharge referred to health centers dependent Shahid Beheshti University in 91-92 were taken by a gynecologist with a dacron swab and put in sterile tubes containing TSB broth and Thioglycollate broth and were immediately sent to the lab location in cold chain for the next stages of investigation. From Thioglycollate and TSB medium was cultured on blood agar and EMB and Palkam and Differential diagnosis environments, and then incubated for 24 h at 37°C. Strains of Lactobacillus rhamnosus were cultured in MRSA environment and were transfered to the lab. After purification of pathogenic bacteria, MIC methods and antibiogram, Lactobacillus rhamnosus inhibitory effect on pathogenic bacteria is checked. Statistical analysis was done by SPSS software v.16.Results: The results of this study show the inhibitory effect of Lactobacillus rhamnosus on some pathogenic bacteria that cause bacterial vaginosis, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus agalactiae, Entrococcus, Listeria monocytogenes and E.Coli. Microscopic examination of stained smears of the large number of Lactobacillus and pathogenic bacteria showed reduced. The prevalence of abnormal vaginal discharge, history of drug use means of preventing pregnancy and douching, respectively, 61%, 55%, 42% and 13% respectively. Significant difference was observed between the use and non-use of IUD in women with bacterial vaginosis infection

  10. Radiation resistance of bacterial populations, isolated from the environment of the radiation sterilization plant type JS-6900, Debrecen

    International Nuclear Information System (INIS)

    Gazso, L.; Igali, S.; Daroczy, E.

    1978-01-01

    The radiation resistance of bacterial populations isolated from the air of an industrial sterilization plant loaded with an activity of 250000 Ci was investigated before loading and a year after loading with 60 Co. The mean D 10 value of the 23 strains isolated before loading was 73 krad with a maximum of 173 krad. The mean D 10 value of the 26 strains isolated a year after loading was 32 krad with a maximum of 156 krad. It was not possible to detect any increase in radiation resistance of bacterial populations isolated from the irradiation room after one year of running radiation sterilization of disposable medical supplies. (author)

  11. Antibiotics resistance of Stenotrophomonas maltophilia strains ...

    African Journals Online (AJOL)

    BD Phoenixautomated microbiology system (Becton Dickinson, USA) was utilized for species level identification and antibiotic susceptibility testing. Results: Sixty seven of S. maltophilia strains were isolated from tracheal aspirate isolates, 17 from blood, 10 from sputum, 10 from wound and 14 from other clinical specimens.

  12. Efficacy of a marine bacterial nuclease against biofilm forming microorganisms isolated from chronic rhinosinusitis.

    Directory of Open Access Journals (Sweden)

    Robert C Shields

    Full Text Available BACKGROUND: The persistent colonization of paranasal sinus mucosa by microbial biofilms is a major factor in the pathogenesis of chronic rhinosinusitis (CRS. Control of microorganisms within biofilms is hampered by the presence of viscous extracellular polymers of host or microbial origin, including nucleic acids. The aim of this study was to investigate the role of extracellular DNA in biofilm formation by bacteria associated with CRS. METHODS/PRINCIPAL FINDINGS: Obstructive mucin was collected from patients during functional endoscopic sinus surgery. Examination of the mucous by transmission electron microscopy revealed an acellular matrix punctuated occasionally with host cells in varying states of degradation. Bacteria were observed in biofilms on mucosal biopsies, and between two and six different species were isolated from each of 20 different patient samples. In total, 16 different bacterial genera were isolated, of which the most commonly identified organisms were coagulase-negative staphylococci, Staphylococcus aureus and α-haemolytic streptococci. Twenty-four fresh clinical isolates were selected for investigation of biofilm formation in vitro using a microplate model system. Biofilms formed by 14 strains, including all 9 extracellular nuclease-producing bacteria, were significantly disrupted by treatment with a novel bacterial deoxyribonuclease, NucB, isolated from a marine strain of Bacillus licheniformis. Extracellular biofilm matrix was observed in untreated samples but not in those treated with NucB and extracellular DNA was purified from in vitro biofilms. CONCLUSION/SIGNIFICANCE: Our data demonstrate that bacteria associated with CRS form robust biofilms which can be reduced by treatment with matrix-degrading enzymes such as NucB. The dispersal of bacterial biofilms with NucB may offer an additional therapeutic target for CRS sufferers.

  13. [Bacterial endosymbiosis within the cytoplasm of Acanthamoeba lugdunensis isolated from a contact lens storage case].

    Science.gov (United States)

    Chung, D I; Kong, H H; Kim, T H; Hwang, M Y; Yu, H S; Yun, H C; Seol, S Y

    1997-06-01

    Transmission electron microscopy of an Acanthamoeba isolate (KA/L5) from a contact lens case revealed bacterial endosymbionts within cytoplasm of the amoebae. The Acanthamoeba isolate belonged to the morphological group II. Based on the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) of 18S ribosomal RNA coding DNA (rDNA), the isolate was identified as A. lugdunensis. Strain typing by isoenzyme analysis using isoelectric focusing (IEF) and mitochondrial (Mt) DNA RFLP revealed that the isolate was closely related with KA/L1, the most predominant type of isolates from contact lens storage cases, KA/E2, a clinical isolate, KA/W4, previously reported to host endosymbionts, and L3a strains of A. lugdunensis. The endosymbionts were similar to those of KA/W4 in aspects that they were randomly distributed in both trophozoites and cysts, and were rod-shaped bacteria measuring approximately 1.38 x 0.50 microns. But the number of endosymbionts per amoeba was significantly lower than that of KA/W4. They were neither limited by phagosomal membranes nor included in lacunaelike structure.

  14. Biosynthesis of Bio surfactant by Egyptian Local Bacterial Isolates Using Different Agricultural Wastes

    International Nuclear Information System (INIS)

    El-Shahawy, M.R.

    2014-01-01

    Fifteen bacterial isolates were isolated from sea water from the coast of the General Petroleum Company on Suez Gulf. They were screened for bio surfactant production using emulsification activity and haemolytic activity. The most potent isolate B11 were selected according to two parameters: The ability to grow and produce surfactant and its haemolytic activity on blood agar plates. The isolate B11 was characterized and identified as Bacillus licheniformis according to API system. The isolate was subjected to different doses of gamma irradiation in a trial to improve its ability for bio surfactant production which resulted in a passive effect on bio surfactant production. Three types of agricultural wastes (Rice straw, Cane Bagasse, Corn straw) were used as fertilizers for bio surfactant biosynthesis by the promising isolate in concentrations of 1, 2, 3, 4, 5 g/l. At five g/l concentration cane bagasse gave high production of bio surfactant with maximum capacity at (32%) flowed by rice straw at 18% and corn straw at 9.8 %.

  15. Application of silica magnetite nanocomposites to the isolation of ultrapure plasmid DNA from bacterial cells

    Science.gov (United States)

    Chiang, Chen-Li; Sung, Ching-Shan; Chen, Chuh-Yean

    2006-10-01

    The aim of this study was to develop a simple and rapid method for purification of ultrapure plasmid DNA with high yields from bacterial cultures. Nanosized superparamagnetic nanoparticles (Fe 3O 4) were prepared by chemical precipitation method using Fe 2+, Fe 3+ salt, and ammonium hydroxide under a nitrogen atmosphere. Silica-magnetite nanocomposites were prepared by the method of acid hydrolysis of tetraethoxysilane (TEOS) to coat the silica onto magnetite nanoparticles. DNA was adsorbed to the support under high salt conditions, and recovered directly in water for immediate downstream application, without the need for precipitation. We demonstrated that a useful plasmid, pRSETB-EGFP, encoding for the green fluorescent protein with T7 promoter, could be amplified in Escherichia coli of DE3 strain. Up to approximately 43 μg of high-purity ( A260/ A280 ratio=1.75) plasmid DNA was isolated from 3 ml of an overnight bacterial culture. The eluted plasmid DNA was used directly for restriction enzyme digestion, bacterial cell transformation and polymerase chain reaction (PCR) amplification with success. The protocol, starting from the preparation of bacterial lysate and ending with purified plasmid takes less than 8 min. The silica-magnetite nanocomposites deliver significant time-savings, overall higher yields, lower RNA contamination, and better PCR amplification compared to commercial available silica-based and other methods.

  16. Bacteriophages isolated from Lake Michigan demonstrate broad host-range across several bacterial phyla.

    Science.gov (United States)

    Malki, Kema; Kula, Alex; Bruder, Katherine; Sible, Emily; Hatzopoulos, Thomas; Steidel, Stephanie; Watkins, Siobhan C; Putonti, Catherine

    2015-10-09

    The study of bacteriophages continues to generate key information about microbial interactions in the environment. Many phenotypic characteristics of bacteriophages cannot be examined by sequencing alone, further highlighting the necessity for isolation and examination of phages from environmental samples. While much of our current knowledge base has been generated by the study of marine phages, freshwater viruses are understudied in comparison. Our group has previously conducted metagenomics-based studies samples collected from Lake Michigan - the data presented in this study relate to four phages that were extracted from the same samples. Four phages were extracted from Lake Michigan on the same bacterial host, exhibiting similar morphological characteristics as shown under transmission electron microscopy. Growth characteristics of the phages were unique to each isolate. Each phage demonstrated a host-range spanning several phyla of bacteria - to date, such a broad host-range is yet to be reported. Genomic data reveals genomes of a similar size, and close similarities between the Lake Michigan phages and the Pseudomonas phage PB1, however, the majority of annotated genes present were ORFans and little insight was offered into mechanisms for host-range. The phages isolated from Lake Michigan are capable of infecting several bacterial phyla, and demonstrate varied phenotypic characteristics despite similarities in host preference, and at the genomic level. We propose that such a broad host-range is likely related to the oligotrophic nature of Lake Michigan, and the competitive benefit that this characteristic may lend to phages in nature.

  17. Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis

    Directory of Open Access Journals (Sweden)

    Abdjad Asih Nawangsih

    2011-04-01

    Full Text Available Xanthomonas oryzae pv oryzae the Causal Agent of Bacterial Leaf Blight of rice: Isolation, Characterization, and Study of Transposon Mutagenesis. X. oryzae pv. oryzae (Xoo causes bacterial leaf blight (BLB of rice (Oryza sativa L., a major disease that constrains production of the staple crop in many countries of the world. Identification of X. oryzae pv. oryzae (Xoo was conducted based on the disease symptoms, pathogenicity, morphological, physiological, and genetic characteristics of bacterial cultures isolated from the infected plants. Fifty bacterial isolates predicted as Xoo have been successfully isolated. They are aerobic, rod shaped, and Gram negative bacteria. The isolates were evaluated for their hypersensitivity in tobacco and pathogenicity in rice plant. Fifty isolates induced hypersensitive reaction in tobacco and showed pathogenicity symptom in rice in different length. Based on physiological test, hypersensitivity and pathogenicity reactions, three bacterial isolates strongly predicted as Xoo, i.e. STG21, STG42, and STG46, were non indole formation, non pigment fluorescent, hydrolyzed casein, catalase activity positive, but negative oxidase. Partial sequencing of 16S rRNA genes of STG21 and STG42 showed 80% and 82% homology with X. oryzae, respectively, while STG46 showed 84% homology with X. campestris. Mini-Tn5 transposon mutagenesis of STG21 generated one of the mutants (M5 lossed it’s ability to induce hypersensitive reaction in tobacco plant and deficient in pathogenicity on rice. The lesion length of rice leaf caused by the mutant M5 decreased up to 80%.

  18. NORMAL VAGINAL BACTERIAL FLORA OF GIANT PANDAS (AILUROPODA MELANOLEUCA) AND THE ANTIMICROBIAL SUSCEPTIBILITY PATTERNS OF THE ISOLATES.

    Science.gov (United States)

    Yang, Xin; Yang, Jiang; Wang, Hongning; Li, Caiwu; He, Yongguo; Jin, SenYan; Zhang, Hemin; Li, Desheng; Wang, Pengyan; Xu, Yuesong; Xu, Changwen; Fan, Chengyun; Xu, Lulai; Huang, Shan; Qu, Chunmao; Li, Guo

    2016-06-01

    To study the typical vaginal bacterial flora of giant pandas (Ailuropoda melanoleuca), we took vaginal swabs for the sake of bacterial isolation, from 24 healthy female giant pandas. A total of 203 isolates were identified, representing a total of 17 bacterial species. The most common bacteria isolated were Lactobacillus spp. (54.2%, 13/24), followed by Staphylococcus epidermidis (41.7%, 10/24) and Escherichia coli (33.3%, 8/24). Some opportunistic pathogenic bacteria, such as Peptostreptococcus spp., Klebsiella pneumoniae , and Proteus mirabilis , were also isolated but showed no pathology. Antimicrobial susceptibility testing of aerobic bacterial isolates was performed with the disk diffusion method. Of the 152 isolates, resistance was most frequently observed with chloramphenicol (17.8%), followed by tetracycline (14.5%), ciprofloxacin (12.5%), streptomycin (11.8%), and florfenicol (11.8%), whereas 7.2% were multidrug resistant. This is the first report of the normal culturable vaginal bacterial flora of giant pandas and the antimicrobial susceptibility patterns of the isolates.

  19. Antimicrobial drug resistance among clinically relevant bacterial isolates in sub-Saharan Africa: a systematic review.

    Science.gov (United States)

    Leopold, Stije J; van Leth, Frank; Tarekegn, Hayalnesh; Schultsz, Constance

    2014-09-01

    Little is known about the prevalence of antimicrobial resistance (AMR) amongst bacterial pathogens in sub-Saharan Africa (sSA), despite calls for continent-wide surveillance to inform empirical treatment guidelines. We searched PubMed and additional databases for susceptibility data of key pathogens for surveillance, published between 1990 and 2013. Extracted data were standardized to a prevalence of resistance in populations of isolates and reported by clinical syndrome, microorganism, relevant antimicrobial drugs and region. We identified 2005 publications, of which 190 were analysed. Studies predominantly originated from east sSA (61%), were hospital based (60%), were from an urban setting (73%) and reported on isolates from patients with a febrile illness (42%). Quality procedures for susceptibility testing were described in resistance to chloramphenicol in Enterobacteriaceae, isolated from patients with a febrile illness, ranged between 31.0% and 94.2%, whilst MP of resistance to third-generation cephalosporins ranged between 0.0% and 46.5%. MP of resistance to nalidixic acid in Salmonella enterica Typhi ranged between 15.4% and 43.2%. The limited number of studies providing prevalence data on AMR in Gram-positive pathogens or in pathogens isolated from patients with a respiratory tract infection, meningitis, urinary tract infection or hospital-acquired infection suggested high prevalence of resistance to chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline and low prevalence to third-generation cephalosporins and fluoroquinolones. Our results indicate high prevalence of AMR in clinical bacterial isolates to antimicrobial drugs commonly used in sSA. Enhanced approaches for AMR surveillance are needed to support empirical therapy in sSA. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Bacterial succession during curing process of a skate (Dipturus batis) and isolation of novel strains.

    Science.gov (United States)

    Reynisson, E; Thornór Marteinsson, V; Jónsdóttir, R; Magnússon, S H; Hreggvidsson, G O

    2012-08-01

    To study the succession of cultivated and uncultivated microbes during the traditional curing process of skate. The microbial diversity was evaluated by sequencing 16Sr RNA clone libraries and cultivation in variety of media from skate samples taken periodically during a 9-day curing process. A pH shift was observed (pH 6·64-9·27) with increasing trimethylamine (2·6 up to 75·6 mg N per 100 g) and total volatile nitrogen (TVN) (from 58·5 to 705·8 mg N per 100 g) but with relatively slow bacterial growth. Uncured skate was dominated by Oceanisphaera and Pseudoalteromonas genera but was substituted after curing by Photobacterium and Aliivibrio in the flesh and Pseudomonas on the skin. Almost 50% of the clone library is derived from putative undiscovered species. Cultivation and enrichment strategies resulted in isolation of putatively new species belonging to the genera Idiomarina, Rheinheimera, Oceanisphaera, Providencia and Pseudomonas. The most abundant genera able to hydrolyse urea to ammonia were Oceanisphaera, Psychrobacter, Pseudoalteromonas and isolates within the Pseudomonas genus. The curing process of skate is controlled and achieved by a dynamic bacterial community where the key players belong to Oceanisphaera, Pseudoalteromonas, Photobacterium, Aliivibrio and Pseudomonas. For the first time, the bacterial population developments in the curing process of skate are presented and demonstrate a reservoir of many yet undiscovered bacterial species. No Claim to Norwegian Government works Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  1. Determination of the hydrocarbon-degrading metabolic capabilities of tropical bacterial isolates

    Energy Technology Data Exchange (ETDEWEB)

    Marquez-Rocha, F.J.; Olmos-Soto, J. [Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, San Diego, CA (United States). Departamento de Biotecnologia Marina; Rosano-Hernandez, M.A.; Muriel-Garcia, M. [Instituto Mexicano del Petroleo, CD Carmen Camp (Mexico). Zona Marina/Tecnologia Ambiental

    2005-01-01

    Of more than 20 bacteria isolated from a tropical soil using minimal medium supplemented with hydrocarbons, 11 grew well on diesel as sole carbon source, and another 11 grew in the presence of polynuclear aromatic hydrocarbons (PAHs). Ten isolates were identified phenotypically as Pseudomonas sp. and eight as Bacillus sp. Gene sequences representing the catabolic genes (alkM, todM, ndoM, and xylM) and 16S rRNA gene sequences characteristic for Pseudomona and Bacillus were amplified by PCR, using DNA recovered from the supernatant of hydrocarbon-contaminated soil suspensions. Based on their rapid growth characteristics in the presence of hydrocarbons and the formation of PCR products for the catabolic genes alkM and ndoM six isolates were selected for biodegradation assays. After 30 days a mixed culture of two isolates achieved close to 70% hydrocarbon removal and apparent mineralization of 16% of the hydrocarbons present in the soil. Biodegradation rates varied from 275 to 387 mg hydrocarbon kg{sup -1} day{sup -1}. Several bacterial isolates obtained in this study have catabolic capabilities for the biodegradation of alkanes and aromatic hydrocarbons including PAHs. (author)

  2. Impact of in Situ Isolated Bacterial Strains on Nitrogen Fixation in Alfalfa

    Directory of Open Access Journals (Sweden)

    Carmen Dragomir

    2013-05-01

    Full Text Available Symbiosis relationships among legumes and nitrogen fixing bacteria play a crucial role in agriculture since they provide the opportunity of converting atmospheric molecular nitrogen into an ammonia form of nitrogen that the plants can use in protein formation. To enhance this process we have selected nitrogen fixing bacterial strains commercialised under different forms depending on the cultivation technologies in legume species. In our research, we have pointed out the efficacy of in situ isolated nitrogen fixing bacteria in alfalfa in two ways: rhizobia taken directly from the nodosities on the alfalfa roots and rhizobia taken from the alfalfa root system.

  3. Distribution, antibiotic susceptibility and tolerance of bacterial isolates in culture-positive cases of endocarditis in The Netherlands

    NARCIS (Netherlands)

    van der Meer, J. T.; van Vianen, W.; Hu, E.; van Leeuwen, W. B.; Valkenburg, H. A.; Thompson, J.; Michel, M. F.

    1991-01-01

    During a two-year period data were collected nationwide in The Netherlands on 438 episodes of bacterial endocarditis (BE) in 432 patients. Of the strains isolated in these patients 419 were available for analysis. Of these, 326 were isolated in native valve endocarditis (NVE) and 93 in prosthetic

  4. Susceptibility of different bacterial species isolated from food animals to copper sulphate, zinc chloride and antimicrobial substances used for disinfection

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Hasman, Henrik

    2004-01-01

    A total of 569 different bacterial isolates (156 Salmonella, 202 E. coli, 43 S. aureus, 38 S. hyicus, 52 E. faecalis, 78 E faecium) were tested for susceptibility to copper sulphate, benzalkonium chloride, hydrogen peroxide and chlorhexidine using MIC determinations. A total of 442 isolates were...

  5. Evidence for dose-dependent effects on plant growth by Stenotrophomonas strains from different origins.

    Science.gov (United States)

    Suckstorff, I; Berg, G

    2003-01-01

    To assess the influence of Stenotrophomonas on plants, the interaction of 16 Stenotrophomonas strains from clinical and environmental sources with strawberry plant seedlings was analysed. In vitro, all Stenotrophomonas strains influenced plant growth when applied to seedlings. Whereas most of the Stenotrophomonas strains promoted root growth and hair development, a statistically significantly negative influence on the length of stem was found. Although strains from a clinical origin also showed statistically significant effects on plants, this was generally lower when compared with environmental strains. For three selected strains, a strong dose-dependent effect was observed for all parameters. In vitro, a correlation was found between plant growth promotion and production of a plant growth hormone, indole-3-acetic acid (IAA). Xanthomonas campestris, a phylogenetically very closely related species to Stenotrophomonas, was used as a phytopathogenic control. It too confirmed the reduction of plant growth in this in vitro system. Independent of their origin, Stenotrophomonas strains can produce IAA in vitro and subsequently, influence plant growth. The effect of Stenotrophomonas presence on plants was dose-dependent. The dose-dependent effect of Stenotrophomonas, a bacterium of both biotechnological and medical interest, is of great interest for biocontrol applications of plant-associated strains. This paper is the first report that clearly demonstrates the phytopathogenic capacity of Stenotrophomonas.

  6. Occurrence and antibacterial susceptibility pattern of bacterial pathogens isolated from diarrheal patients in Pakistan

    Directory of Open Access Journals (Sweden)

    Muhammad H. Rasool

    2016-03-01

    Full Text Available Objective: To determine the occurrence of bacterial pathogens responsible for diarrhea and to engender information regarding the effectiveness of commonly used antibiotic against diarrhea. Methods: This cross-sectional study was conducted between April and July 2014. Samples were collected from the Divisional Headquarter and Allied Hospital, Faisalabad, Pakistan. The differential and selective media were used to isolate bacterial pathogens, which were identified through cultural characteristics, microscopy, and biochemical tests. Disc diffusion assay was carried out using Muller Hinton agar medium, and minimum inhibitory concentration was determined using broth dilution method against isolated pathogens. Results: One hundred and forty-one (100% samples were positive for some bacteria. Frequency of occurrence was Bacillus cereus (B. cereus (66%, Escherichia coli (E. coli (48.5%, Salmonella typhi (S. Typhi (27.7%, Pseudomonas aeruginosa (P. aeruginosa (8.5%, and Staphylococcus aureus (S. aureus (4.3%. Single pathogen was detected in 20 (14.2% samples whereas combinations were found in 121 (85.8% samples. Bacillus cereus and E. coli were the most frequently detected pathogens followed by the S. Typhi, P. aeruginosa, and Staph. aureus. The percentage occurrence of isolated pathogens was 31% in B. cereus, 31% in E. coli, 18% in S. Typhi, 5% in P. aeruginosa, and 3% in Staph. aureus. Conclusion: Pseudomonas aeruginosa showed resistance against Amoxicillin and Cefotaxime, whereas S. aureus was found resistant against Cefotaxime. Statistical analysis using one way Analysis of Variance revealed that Ofloxacin and Gentamicin had significant (p<0.05 differences against all isolates as compared with other antibiotics used in this study.

  7. Chitosanase purified from bacterial isolate Bacillus licheniformis of ruined vegetables displays broad spectrum biofilm inhibition.

    Science.gov (United States)

    Muslim, Sahira Nsayef; Al-Kadmy, Israa M S; Hussein, Nadheema Hammood; Mohammed Ali, Alaa Naseer; Taha, Buthainah Mohammed; Aziz, Sarah Naji; Kheraif, Abdulaziz Abdullah Al; Divakar, Darshan Devang; Ramakrishnaiah, Ravikumar

    2016-11-01

    A number of bacterial species produces chitosanases which has variety of applications because of its high biodegradability, non-toxicity and antimicrobial assets. In the present study chitosanase is purified from new bacterial species Bacillus licheniformis from spoiled vegetable. This novel strain of Bacillus licheniformis isolated from spoilt cucumber and pepper samples has the ability to produce the chitosanase enzyme when grown on chitosan substrate. Study also examined its antibiofilm properties against diverse bacterial species with biofilm forming ability. The purified chitosanase inhibited the biofilm formation ability for all Gram-negative and Gram-positive biofilm-forming bacteria [biofilm producers] tested in this study in congo red agar and microtiter plate's methods. Highly antibiofilm activity of chitosanase was recorded against Pseudomonas aeruginosa followed by Klebsiella pneumoniae with reduction of biofilm formation upto 22 and 29%, respectively compared with [100] % of control. Biofilm formation has multiple role including ability to enhance resistance and self-protection from external stress. This chitosanase has promising benefit as antibiofilm agent against biofilm forming pathogenic bacteria and has promising application as alternative antibiofilm agents to combat the growing number of multidrug resistant pathogen-associated infections, especially in situation where biofilms are involved. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Dark fermentative biohydrogen production by mesophilic bacterial consortia isolated from riverbed sediments

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Sneha; Sudhakaran, Anu K.; Sarma, Priyangshu Manab; Subudhi, Sanjukta; Mandal, Ajoy Kumar; Lal, Banwari [Environmental and Industrial Biotechnology Division, The Energy and Resources Institute (TERI), Habitat Place, Darbari Seth Block, Lodhi Road, New Delhi 110003 (India); Gandham, Ganesh [Hindustan Petroleum Corporation Limited, Mumbai Refinery, B. D. Patil Marg, Mahul, Mumbai 400074 (India)

    2010-10-15

    Dark fermentative bacterial strains were isolated from riverbed sediments and investigated for hydrogen production. A series of batch experiments were conducted to study the effect of pH, substrate concentration and temperature on hydrogen production from a selected bacterial consortium, TERI BH05. Batch experiments for fermentative conversion of sucrose, starch, glucose, fructose, and xylose indicated that TERI BH05 effectively utilized all the five sugars to produce fermentative hydrogen. Glucose was the most preferred carbon source indicating highest hydrogen yields of 22.3 mmol/L. Acetic and butyric acid were the major soluble metabolites detected. Investigation on optimization of pH, temperature, and substrate concentration revealed that TERI BH05 produced maximum hydrogen at 37 C, pH 6 with 8 g/L of glucose supplementation and maximum yield of hydrogen production observed was 2.0-2.3 mol H{sub 2}/mol glucose. Characterization of TERI BH05 revealed the presence of two different bacterial strains showing maximum homology to Clostridium butyricum and Clostridium bifermentans. (author)

  9. Characterization of corrosive bacterial consortia isolated from petroleum-product-transporting pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Rajasekar, Aruliah; Ting, Yen-Peng [National Univ. of Singapore (Singapore). Dept. of Chemical and Biomolecular Engineering; Anandkumar, Balakrishnan [Sourashtra Coll., Madurai (India). Dept. of Biotechnology; Maruthamuthu, Sundaram [Central Electrochemical Research Inst., Karaikudi (India). Biocorrosion Group; Rahman, Pattanathu K.S.M. [Teesside Univ., Tees Valley (United Kingdom). Chemical and Bioprocess Engineering Group

    2010-01-15

    Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species in biofilm formation and steel corrosion is discussed. (orig.)

  10. In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate.

    Science.gov (United States)

    Mengistu, Y; Erge, W; Bellete, B

    1999-05-01

    To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Prospective laboratory study. Tikur Anbessa Hospital, Addis Ababa, Ethiopia. Clinical specimens from 443 hospital patients. Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis. Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniae (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to 1%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC or = 0.1%). Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.

  11. Cadmium Bio sorption by Some Bacterial Isolates and Their Mutants Induced by gamma Radiation

    International Nuclear Information System (INIS)

    Tawfik, Z.S.; Elsonbaty, S.M.; Abdalla, N.M.

    1999-01-01

    Cadmium bio sorption by bacterial cells is recognized as a potential alternative to existing recovery technologies. Bacterial strains under investigation were isolated from air surrounding gamma industrial facility Co 60 source of the NCRRT, Cairo. The effect of different concentrations of cadmium on the growth was determined for the spore forming bacteria B.coagulans, B.megaterium, B.pumilus, B.pantothenticus, and also for Staphylo coccus aureus, the reference standard strain used in these study for comparison was B.subtilis MERK 10646. The results indicated that, B.pantothenticus was the most tolerant isolate, and it can resist up to 400 ppm. Cadmium capacity for B.subtilis parent strain was increased through the influence of different doses of gamma radiation, selected mutant of B.subtilis show enhanced level of cadmium accumulation. The effect of environmental parameters as ph, temperature and also the effect of biomass factor on cadmium uptake by B.pantothenticus and B.subtilis (m) was traced

  12. Occurrence of plasmid linked multiple drug resistance in bacterial isolates of tannery effluent.

    Science.gov (United States)

    Naraian, R; Ram, S; Kaistha, S D; Srivastava, J

    2012-12-22

    Effluents of three different tanneries (T-1, T-2, & T-3) were investigated to isolate and scrutinize antibiotic, chromate and salinity resistant bacteria. Total 18 isolates of 9 different bacterial genera were screened out and identified; some strains established in all effluents. Amongst the three effluents tested; T-1 exhibited largest population of all isolates compared to T-2 and T-3 effluents. The T-1 effluent contained largest 4.4 x10(6) cfu/ml population of Pseudomonas aeruginosa followed by 3.9 x10(6) cfu/ml in T-2 effluent. The lowest 0.7 x10(6) cfu/ml count of Aeromonas spp. was recorded in T-3 effluent. Furthermore, antibiotic susceptibility tests were performed with 7 antibiotics which include ampicillin, sulfafurazole, ciprofloxacin, norfloxacin, tetracycline and amikacin. Three strains of P. aeruginosa and one strain of Escherichia coli deserved as multiple drug resistant (MDR). The P. aeruginosaT-3 and E. coliT-1 showed strongest MDR feature for 5 antibiotics. The response of chromate (50, 100, 200, 250 and 300 μg/ml) and NaCl concentrations (20, 40, 60 and 80 g/l) was incredible for 4 MDR isolates. Nearly each strain showed tolerance up to 300 μg/ml of chromate and 80 g/l of NaCl. The P. aeruginosaT-1, P. aeruginosaT-2, P. aeruginosaT-3 and E. coliT-1 were most tolerant isolates. Plasmid profiling of resistant strains was conducted with agarose gel electrophoresis. As consequence, plasmids from two strains of P. aeruginosa and E. coliT-1 represented different bands. At least for confirmation of plasmids nature; these were transformed and transformants were screened on medium having antibiotics. The study of plasmid transformation has confirmed the plasmid mediated resistance in isolates.

  13. Nematode-trapping fungi and fungus-associated bacteria interactions: the role of bacterial diketopiperazines and biofilms on Arthrobotrys oligospora surface in hyphal morphogenesis.

    Science.gov (United States)

    Li, Lei; Yang, Min; Luo, Jun; Qu, Qing; Chen, Ying; Liang, Lianming; Zhang, Keqin

    2016-11-01

    In soil, nematode-trapping fungi and bacteria often share microhabitats and interact with each other, but effects of fungus-associated bacteria on its trap formation are underestimated. We have ascertained the presence of Stenotrophomonas and Rhizobium genera associated with A. oligospora GJ-1. After A. oligospora GJ-1 without associated bacteria (cured Arthrobotrys) was co-cultivated with Stenotrophomonas and its supernatant extract, microscopic study of hyphae from co-cultivation indicated that bacterial biofilm formation on hyphae was related to trap formation in fungi and Stenotrophomonas supernatant extract. Four diketopiperazines (DKPs) were purified from Stenotrophomonas supernatant extract that could not induce traps in the cured Arthrobotrys. When cured Arthrobotrys was cultured with Stenotrophomonas and one of DKPs, polar attachment, bacterial biofilms on hyphae and trap formation in fungi were observed. After cured Arthrobotrys with bacterial biofilms was consecutively transferred several times on nutrient poor medium, trap formation disappeared with the disappearance of bacterial biofilms on hyphae. DKPs could facilitate chemotaxis of Stenotrophomonas towards fungal extract which was suggested to contribute to bacterial biofilms on hyphae. Furthermore, when cured Arthrobotrys was cultured with Stenotrophomonas and DKPs in soil, trap formation in fungi and bacterial biofilms on hyphae were also observed, and the fungal activity against nematode was enhanced. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  14. Bacterial isolates associated with pelvic inflammatory disease among female patients attending some hospitals in abuja, Nigeria.

    Science.gov (United States)

    Spencer, T H I; Umeh, P O; Irokanulo, E; Baba, M M; Spencer, B B; Umar, A I; Ardzard, S A; Oderinde, S; Onoja, O

    2014-01-01

    Pelvic inflammatory disease refers to any infection in the female lower reproductive tract that spreads to the upper reproductive tract. The disease comprises a spectrum of inflammatory disorders of the upper female genital tract, including any combination of endometritis, salpingitis, tubo-ovarian abscess and pelvic peritonitis. PID is not a notifiable disease in most countries, so accurate statistics are not available. This situation is not in any way different here in Nigeria and more so in the Federal Capital Territory, Abuja where this research was conducted, there had never been any published report so far on PID. It therefore became pertinent that such studies be carried out to evaluate the bacterial organisms which may be associated with the disease in this part of Nigeria so that health care providers could take a better look at this affliction in women. Endocervical swabs totalling 100 were aseptically collected from patients with confirmed Pelvic Inflammatory Disease (PID), attending some hospitals in Abuja, Nigeria for detection of bacterial pathogens based on cultural and biochemical characterisation tests. Antibiogram was also conducted on the identified bacterial isolates. Out of the 100 samples analysed, 43% yielded pure cultures of bacterial isolates, 2% yielded mixed cultures while no bacterial growths were recorded from the remaining 55% samples. Organisms encountered were Staphylococcus aureus (16%), Escherichia coli (10%), Streptococcus faecalis (8%), Pseudomonas aeruginosa (4%), Streptococcus pyogenes (3%), Klebsiella pneumoniae (3%), Proteus rettgeri (2%) and Proteus mirabilis (1%). The highest percentage occurrence of pathogenic isolates was observed in polygamous married patients (90%). The age group most affected falls within the mean age 30.5 years (68%) while the least affected group falls within the mean age 40.5 years (5%). There was a significant difference in the acquisition of PID in relation to marital status (P disease with

  15. Propionibacterium acnes bacteriophages display limited genetic diversity and broad killing activity against bacterial skin isolates.

    Science.gov (United States)

    Marinelli, Laura J; Fitz-Gibbon, Sorel; Hayes, Clarmyra; Bowman, Charles; Inkeles, Megan; Loncaric, Anya; Russell, Daniel A; Jacobs-Sera, Deborah; Cokus, Shawn; Pellegrini, Matteo; Kim, Jenny; Miller, Jeff F; Hatfull, Graham F; Modlin, Robert L

    2012-01-01

    Investigation of the human microbiome has revealed diverse and complex microbial communities at distinct anatomic sites. The microbiome of the human sebaceous follicle provides a tractable model in which to study its dominant bacterial inhabitant, Propionibacterium acnes, which is thought to contribute to the pathogenesis of the human disease acne. To explore the diversity of the bacteriophages that infect P. acnes, 11 P. acnes phages were isolated from the sebaceous follicles of donors with healthy skin or acne and their genomes were sequenced. Comparative genomic analysis of the P. acnes phage population, which spans a 30-year temporal period and a broad geographic range, reveals striking similarity in terms of genome length, percent GC content, nucleotide identity (>85%), and gene content. This was unexpected, given the far-ranging diversity observed in virtually all other phage populations. Although the P. acnes phages display a broad host range against clinical isolates of P. acnes, two bacterial isolates were resistant to many of these phages. Moreover, the patterns of phage resistance correlate closely with the presence of clustered regularly interspaced short palindromic repeat elements in the bacteria that target a specific subset of phages, conferring a system of prokaryotic innate immunity. The limited diversity of the P. acnes bacteriophages, which may relate to the unique evolutionary constraints imposed by the lipid-rich anaerobic environment in which their bacterial hosts reside, points to the potential utility of phage-based antimicrobial therapy for acne. Propionibacterium acnes is a dominant member of the skin microflora and has also been implicated in the pathogenesis of acne; however, little is known about the bacteriophages that coexist with and infect this bacterium. Here we present the novel genome sequences of 11 P. acnes phages, thereby substantially increasing the amount of available genomic information about this phage population

  16. 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

  17. Microbiological and molecular identification of bacterial species isolated from nasal and oropharyngeal mucosa of fuel workers in Riyadh, Saudi Arabia.

    Science.gov (United States)

    AlWakeel, Suaad S

    2017-09-01

    This study aimed to determine the bacterial species colonizing the nasal and oropharyngeal mucosa of fuel workers in Central Riyadh, Saudi Arabia on a microbiological and molecular level. Throat and nasal swab samples were obtained from 29 fuel station attendants in the period of time extending from March to May 2014 in Riyadh, Saudi Arabia. Microbiological identification techniques were utilized to identify the bacterial species isolated. Antibiotic sensitivity was assessed for each of the bacterial isolates. Molecular identification techniques based on PCR analysis of specific genomic sequences was conducted and was the basis on which phylogeny representation was done for 10 randomly selected samples of the isolates. Blood was drawn and a complete blood count was conducted to note the hematological indices for each of the study participants. Nineteen bacterial species were isolated from both the nasal cavity and the oropharynx including Streptococcus thoraltensis , alpha-hemolytic streptococci, Staphylococcus hominis , coagulase-negative staphylococci, Leuconostoc mesenteroides , Erysipelothrix rhusiopathiae and several others. We found 100% sensitivity of the isolates to ciprofloxacin, cefuroxime and gentamicin. Whereas cefotaxime and azithromycin posted sensitivities of 85.7% and 91.4%, respectively. Low sensitivities (fuel products may be a contributing factor to bacterial colonization of the respiratory tract in fuel workers.

  18. Trends in antibiotic resistance in bacterial keratitis isolates from South India.

    Science.gov (United States)

    Lalitha, Prajna; Manoharan, Geetha; Karpagam, Rajaram; Prajna, Namperumalsamy V; Srinivasan, Muthiah; Mascarenhas, Jeena; Das, Manoranjan; Porco, Travis C; Lietman, Thomas M; Cevallos, Vicky; Keenan, Jeremy D

    2017-02-01

    To report trends in antibiotic resistance in cases of bacterial keratitis from a large eye hospital in South India. In this retrospective cross-sectional study, the microbiology laboratory records of patients with infectious keratitis diagnosed at an eye hospital in South India from 2002 to 2013 were reviewed to determine the proportion with antibiotic non-susceptibility. 3685 bacterial isolates had susceptibility testing performed over the 12-year period. The two most common organisms with resistance were Streptococcus pneumoniae (n=1204) and Pseudomonas aeruginosa (n=894). Antibiotic non-susceptibility was generally uncommon for these two organisms and no significant trends were detected over the course of the study. In contrast, Staphylococcus aureus (N=211) isolates demonstrated a significant increase in fluoroquinolone non-susceptibility over the 12-year study period. This coincided with a significant increase in methicillin-resistant S. aureus (MRSA) during the study period, though the increase in fluoroquinolone resistance was likewise seen in methicillin-sensitive S. aureus (MSSA). For example, ofloxacin resistance in MSSA increased from 11.1% in 2002 to 66.7% in 2013 (p=0.002). No trends were apparent for the aminoglycosides, cefazolin or vancomycin, for which in vitro non-susceptibility generally appeared to be low. Resistance to antibiotics was generally stable for infectious keratitis isolates from a large eye hospital in South India, except for S. aureus, which experienced a significant increase in fluoroquinolone resistance from 2002 to 2013. Fluoroquinolone antibiotics currently have poor in vitro activity against both MRSA and MSSA in South India and are therefore not the ideal therapy for Staphylococcal corneal ulcers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. Antimicrobial activity of endophytic bacterial populations isolated from medical plants of Iran.

    Science.gov (United States)

    Beiranvand, Maryam; Amin, Mansour; Hashemi-Shahraki, Abdolrazag; Romani, Bizhan; Yaghoubi, Sajad; Sadeghi, Parisa

    2017-02-01

    Endophytic actinobacteria colonize inside the plant tissues without causing damages to the host plant. Since these microorganisms colonize in the different parts of plants and can stop plant disease, they have been applied as biological agents for controlling human diseases. The aim of this study was molecular identification and measuring the antimicrobial activity of endophytic Actinomycete s isolated from medicinal plants of Iran. The total of 23 medicinal plant samples were collected, sterilized, and crushed. Small pieces of the crushed samples were then cultured directly on three selective media. Grown colonies were identified by 16S rRNA gene sequencing method. Each isolate was cultured in TSB medium and then antimicrobial compound was extracted using ethyl acetate and tested against the target bacteria. Sixteen out of 23 bacterial isolates (69%) exhibited antimicrobial activity against the selected pathogenic bacteria, such as Bacillus cereus, Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Citrobacter freundii, Proteus mirabilis, Shigella flexneri and Escherichia coli. Our Study showed a high phylogenetic diversity and the potent antibiotic activity of endophytic bacteria in medicinal plants of Iran.

  20. Antimicrobial activity of endophytic bacterial populations isolated from medical plants of Iran

    Science.gov (United States)

    Beiranvand, Maryam; Amin, Mansour; Hashemi-Shahraki, Abdolrazag; Romani, Bizhan; Yaghoubi, Sajad; Sadeghi, Parisa

    2017-01-01

    Background and Objectives: Endophytic actinobacteria colonize inside the plant tissues without causing damages to the host plant. Since these microorganisms colonize in the different parts of plants and can stop plant disease, they have been applied as biological agents for controlling human diseases. The aim of this study was molecular identification and measuring the antimicrobial activity of endophytic Actinomycetes isolated from medicinal plants of Iran. Materials and Methods: The total of 23 medicinal plant samples were collected, sterilized, and crushed. Small pieces of the crushed samples were then cultured directly on three selective media. Grown colonies were identified by 16S rRNA gene sequencing method. Each isolate was cultured in TSB medium and then antimicrobial compound was extracted using ethyl acetate and tested against the target bacteria. Results: Sixteen out of 23 bacterial isolates (69%) exhibited antimicrobial activity against the selected pathogenic bacteria, such as Bacillus cereus, Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Citrobacter freundii, Proteus mirabilis, Shigella flexneri and Escherichia coli. Conclusion: Our Study showed a high phylogenetic diversity and the potent antibiotic activity of endophytic bacteria in medicinal plants of Iran. PMID:28775818

  1. Characterization of boron tolerant bacteria isolated from a fly ash dumping site for bacterial boron remediation.

    Science.gov (United States)

    Edward Raja, Chellaiah; Omine, Kiyoshi

    2013-08-01

    Boron is an essential micronutrient for plants, but can above certain concentrations be toxic to living organisms. A major environmental concern is the removal of boron from contaminated water and fly ash. For this purpose, the samples were collected from a fly ash dumping site, Nagasaki prefecture, Japan. The chemical characteristics and heavy metal concentration of the samples were performed by X-ray fluorescent analysis and leaching test. For bacterial analysis, samples were collected in sterile plastic sheets and isolation was carried out by serial dilution method. The boron tolerant isolates that showed values of maximum inhibitory concentration toward boron ranging from 100 to 260 mM level were screened. Based on 16S rRNA sequencing and phylogenetic analysis, the isolates were most closely related to the genera Bacillus, Lysinibacillus, Microbacterium and Ralstonia. The boron tolerance of these strains was also associated with resistant to several heavy metals, such as As (III), Cr (VI), Cd, Cu, Pb, Ni, Se (III) and Zn. Indeed, these strains were arsenic oxidizing bacteria confirmed by silver nitrate test. These strains exhibited their salt resistances ranging from 4 to 15 % were determined in Trypticase soy agar medium. The boron tolerant strains were capable of removing 0.1-2.0 and 2.7-3.7 mg l(-1) boron from the medium and fly ash at 168 h. Thus, we have successfully identified the boron tolerant and removal bacteria from a fly ash dumping site for boron remediation.

  2. Amylase production potentials of bacterial isolates obtained from the gut of Oryctes rhinoceros larvae

    Science.gov (United States)

    Aryati, P. C.; Pangastuti, A.; Sari, S. L. A.

    2017-04-01

    Amylase is one of the main enzymes used in industry, such as food, detergent, textile, and pharmaceutical industry. Amylase can be produced by plants, animals, and microorganisms. However, bacterial and fungal amylases have dominated application in industries. This research was aimed to determine amylolytic activity of bacteria isolated from the gut of Oryctes rhinoceros larvae. Based on clear zone formation, 9 from 11 isolates showed amylolytic activity. Isolates with the widest clear zone, i.e Bacillus subtilis GOR1, Bacillus cereus GOR3, and Bacillus pumilus GOR2, were screened for amylolytic activity based on reduction sugar production. The result showed that Bacillus subtilis GOR1 was the most potential as amylase producer, showed by the widest clear zone 5.224 cm2 and highest reduction sugar production 0.0235 mg/ml. Highest amylase specific activity (0.1447 U/mg protein) was obtained at 60°C and pH 7. Amylase activity was stable for 3 hours at 60°C with residual activity respectively was 59.7%.

  3. Antimicrobial Activity of Monoramnholipids Produced by Bacterial Strains Isolated from the Ross Sea (Antarctica

    Directory of Open Access Journals (Sweden)

    Pietro Tedesco

    2016-04-01

    Full Text Available Microorganisms living in extreme environments represent a huge reservoir of novel antimicrobial compounds and possibly of novel chemical families. Antarctica is one of the most extraordinary places on Earth and exhibits many distinctive features. Antarctic microorganisms are well known producers of valuable secondary metabolites. Specifically, several Antarctic strains have been reported to inhibit opportunistic human pathogens strains belonging to Burkholderia cepacia complex (Bcc. Herein, we applied a biodiscovery pipeline for the identification of anti-Bcc compounds. Antarctic sub-sea sediments were collected from the Ross Sea, and used to isolate 25 microorganisms, which were phylogenetically affiliated to three bacterial genera (Psychrobacter, Arthrobacter, and Pseudomonas via sequencing and analysis of 16S rRNA genes. They were then subjected to a primary cell-based screening to determine their bioactivity against Bcc strains. Positive isolates were used to produce crude extracts from microbial spent culture media, to perform the secondary screening. Strain Pseudomonas BNT1 was then selected for bioassay-guided purification employing SPE and HPLC. Finally, LC-MS and NMR structurally resolved the purified bioactive compounds. With this strategy, we achieved the isolation of three rhamnolipids, two of which were new, endowed with high (MIC < 1 μg/mL and unreported antimicrobial activity against Bcc strains.

  4. Antibiotic Resistance Pattern of Bacterial Pathogens Isolated from Cow Dung Used to Fertilize Nigerian Fish Ponds

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    Funso S. OMOJOWO

    2013-02-01

    Full Text Available This study was carried out to isolate and identify antibiotic resistant bacteria from cow dung used for pond fertilization. Cow dung from over 200 cows in NIFFR integrated farms, New-Bussa, Nigeria were collected. Six bacterial pathogens; Escherichia coli, E. coli O157:H7, Shigella dysentariae, Staphylococcus aureus, Salmonella typhi, and Aeromonas hydrophila were isolated. Antibiotic susceptibility testing by the disk diffusion method was conducted using ofloxacin, amoxicillin, tetracycline, ampicillin, erythromycin, gentamicin, nalidixic acid and chloramphenicol. All the isolated organisms were 100% sensitive to ofloxacin. The multiple resistance patterns revealed that 100% were resistant to tetracycline, ampicillin (85.6%, amoxicillin (83.3%, chloramphenicol (66%, gentamicin (47.6%, erythromycin (44.4% and nalidixic acid (18.3%. The Public Health risks posed by the cow dung manure include proliferation of ponds with these organisms that are pathogenic to fish and man, contamination of the environment and the possible retention of these organisms in the table size fish.

  5. Disinfectant and antibiotic activities: a comparative analysis in Brazilian hospital bacterial isolates

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    Guimarães Márcia Aparecida

    2000-01-01

    Full Text Available Nosocomial infections are an important cause of morbidity and mortality all over the world. It has been shown that appropriate environmental hygienic and disinfection practices can be very helpful to hospital infection control. The purpose of this study was to evaluate the bactericidal activity of some disinfectants against antibiotic-susceptible and antibiotic-resistant hospital bacterial isolates. The susceptibility of 27 clinical isolates to disinfectants and antibiotics was determined by the Association of Official Analytical Chemist?s (AOAC Use-Dilution method and by the Kirby-Bauer method, respectively. All strains tested were susceptible to sodium hypochlorite, glutaraldehyde and to the association quaternary ammonium - formaldehyde - ethyl alcohol disinfectants. However, the susceptibility of strains to phenol and to one quaternary ammonium compound was variable. Among twenty-one antibiotic-multiresistant strains (methicillin-resistant staphylococci, Enterococcus spp, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Serratia marcescens and Escherichia coli eleven (52% and eight (38% strains were resistant to the quaternary ammonium and phenol compounds, respectively. Among six isolates that demonstrated susceptibility to antibiotics (staphylococci, Enterococcus spp, P. mirabilis, E. cloacae and E. coli two strains (33% showed resistance to these disinfectants. The results demonstrated the lack of correlation between antibiotic-susceptibility and susceptibility to disinfectants in hospital strains.

  6. Isolation and characterization of gut bacterial proteases involved in inducing pathogenicity of Bacillus thuringiensis toxin in cotton bollworm, Helicoverpa armigera

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    Visweshwar Regode

    2016-10-01

    Full Text Available Bacillus thuringiensis (Bt toxin proteins are deployed in transgenic plants for pest management. The present studies were aimed at characterization of gut bacterial proteases involved in activation of inactive Cry1Ac protoxin (pro-Cry1Ac to active toxin in Helicoverpa armigera. Bacterial strains were isolated from H. armigera midgut and screened for their proteolytic activation towards pro-Cry1Ac. Among twelve gut bacterial isolates seven isolates showed proteolytic activity, and proteases from three isolates (IVS1, IVS2 and IVS3 were found to be involved in the proteolytic conversion of pro-Cry1Ac into active toxin. The proteases from IVS1, IVS2 and IVS3 isolates were purified to 11.90-, 15.50- and 17.20-fold, respectively. The optimum pH and temperature for gut bacterial protease activity was 8.0 and 40 oC. Maximum inhibition of total proteolytic activity was exerted by PMSF followed by EDTA. Fluorescence zymography revealed that proteases from IVS1, IVS2, and IVS3 were chymotrypsin-like and showing protease band at ~15, 65 and 15 kDa, respectively. Active Cry1Ac formed from processing pro-Cry1Ac by gut bacterial proteases exhibited toxicity towards H. armigera. The gut bacterial isolates IVS1, IVS2 and IVS3 showed homology with Bacillus thuringiensis (CP003763.1, Vibrio fischeri (CP000020.2 and Escherichia coli (CP011342.1, respectively. Proteases produced by midgut bacteria are involved in proteolytic processing of Bt protoxin and play a major role in inducing pathogenicity of Bt toxins in H. armigera.

  7. Microbiological and biochemical response of certain proteolytic bacterial isolates to varying levels of gamma irradiation

    International Nuclear Information System (INIS)

    El-Hifnawi, H.M.N.E.A.

    1997-01-01

    Amniotic membrane allo - and xeno grafts prepared from human foetal placenta, and their potential replacement of skin autotransplant, would significantly contribute to the success of clinical treatment of skin burns. Allo-and xenografts of human amniotic membrane should be ensured for their sterility, bio-mechanics and tissue antigenicity. The present study has been focused on sterilization and sterility assurance of the membrane grafts. Physico-chemical properties and antigenicity of the grafts await investigation. In the present study the isolation and identification of the bacteria contaminating the amniotic membrane allo-and xenografts prepared from human foetal placenta and the effect of gamma irradiation on it has been investigated. The proteolytic activity of these bacteria and the role of gamma irradiation in the control of bacterial activity were similarly investigated

  8. 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)

  9. Profiling of antibiotic resistance of bacterial species recovered from routine clinical isolates in Ethiopia.

    Science.gov (United States)

    Ten Hove, Robert-Jan; Tesfaye, Melaku; Ten Hove, Witold Frederik; Nigussie, Mesfin

    2017-06-26

    With the alarming rise in antibiotic resistance in African countries, the need for a surveillance system in the region has become pressing. The rapid expansion of data networks makes it possible to set up healthcare applications that can be both cost-efficient and effective. Large data sets are available for assessment of current antibiotic resistance among Ethiopian patients. Based on the data-presentation, a practical approach is proposed on how diagnostic laboratories can participate remedial action against antibiotic resistance in Ethiopia. In Addis Ababa (Ethiopia), raw data comprising bacterial species name, specimen type and antibiograms covering the period January 2014 to May 2015 was accessed from the laboratory information management system. Using R code, the data was read and fitted into data-frames and analyzed to assess antibiotic resistance in the Ethiopian patient population. Susceptibility to an antibiotic was tested with 14.983 cultures of 54 different bacterial species or subgroups, isolated from 16 types of specimen. Half of the cultures (n = 6444) showed resistance to an antibiotic. Resistance against penicillin was highest with, on average, 91.1% of 79 bacterial cultures showing resistance. Very high resistance rates were also observed for ampicillin, whereas resistance was lowest with cefoxitin. Extraction and analysis of raw-data from the laboratory database is relatively simple and can provide valuable insight into the relationships between type of sample and drug-resistance in countries where such data is still scarce. With the largest number of antibiotic resistance tests described for Ethiopia, a tool is proposed for consistent data collection with specified core variables. Trends in antibiotic resistance can be revealed and treatment failures avoided when used as an easy accessible reference application for healthcare providers.

  10. Respiratory bacterial infections in cystic fibrosis

    DEFF Research Database (Denmark)

    Ciofu, Oana; Hansen, Christine R; Høiby, Niels

    2013-01-01

    PURPOSE OF REVIEW: Bacterial respiratory infections are the main cause of morbidity and mortality in patients with cystic fibrosis (CF). Pseudomonas aeruginosa remains the main pathogen in adults, but other Gram-negative bacteria such as Achromobacter xylosoxidans and Stenotrophomonas maltophilia...

  11. Crude bacterial extracts of two new Streptomyces sp. isolates as bio-colorants for textile dyeing.

    Science.gov (United States)

    Kramar, Ana; Ilic-Tomic, Tatjana; Petkovic, Milos; Radulović, Niko; Kostic, Mirjana; Jocic, Dragan; Nikodinovic-Runic, Jasmina

    2014-08-01

    Renewed demand for incorporation of natural dyes (bio-colorants) in textile industry could be met through biotechnological production of bacterial pigments. Two new Streptomyces strains (NP2 and NP4) were isolated for the remarkable ability to produce diffusible deep blue and deep red pigment into fermentation medium. Crude mycelial extracts of both strains were used as bio-colorants in conventional textile dyeing procedures avoiding downstream purification procedures. The yields of bio-colorants obtained in this way were 62 and 84 mg per g of mycelia for Streptomyces sp. NP2 and Streptomyces sp. NP4, respectively. Through nuclear magnetic resonance analysis of crude extracts before and after dyeing procedures, it was shown that both extracts contained prodigiosin-like family of compounds that exhibited different dyeing capabilities towards different textile fibers. Polyamide and acrylic fibers were colored to the deepest shade, polyester and triacetate fibers to a noticeable, but much lower shade depth, while cotton and cellulosic fibers stained weakly. These results confirmed that crude bacterial extracts had the characteristics similar to those of ionic and disperse dyes, which was consistent with the identified polypyrrolic prodigiosin-like structures.

  12. Comparative Antibacterial Efficacy of Vitellaria paradoxa (Shea Butter Tree Extracts Against Some Clinical Bacterial Isolates

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    Kamoldeen Abiodun AJIJOLAKEWU

    2015-09-01

    Full Text Available The antibacterial activities of the ethanolic extracts of seed, leaf and stem bark of Vitellaria paradoxa were investigated. The extracts were tested against three clinical bacterial pathogens, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae using the agar diffusion and the broth dilution techniques. Ethanolic extracts of the plant parts showed activity against all the bacterial pathogens tested. At the highest extract concentration (200 mg/ml, the leaf extract exhibited the highest antimicrobial activity, while no activity was detected at the lowest concentration (3.13 mg/ml against the tested isolates. Escherichia coli and Staphylococcus aureus were more susceptible to all extracts of V. paradoxa, while Klebsiella pneumoniae showed the least sensitivity. The efficacy of ethanolic extracts of Vitellaria paradoxa was compared to a commercial antibiotic streptomycin. There were differences in the minimum inhibitory concentration (MIC of all the Vitellaria paradoxa ethanolic extracts with respect to the type of organism. All extracts exhibited bacteriostatic effects against the tested organisms at the experimented concentrations. Qualitative phytochemical screening of the extracts revealed the presence of saponins, tannins and alkaloids as the active principles of Vitellaria paradoxa's antimicrobial activity. V. paradoxa could be used as a potential source of antibiotic substance for a drug development.

  13. Bacterial Agents Andantibiogram of Most Common Isolated Organisms from Hands of Surgical Team Members after Scrubbing

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    PS Mohseni- Meybodi

    2008-04-01

    Full Text Available Introduction: Many post-surgical wound infections in hospitals cause morbidity and morality of patients and these are usually transmitted via hands of surgical personnel. The aim of the present study was to detect and antibiogram the bacterial agents following scrubbing of hands of surgical personnel before operation. Methods: Hands of 134 personnels of operation room were swabbed following scrubbing with antiseptic Betadine solution. Swab samples were inoculated on selective and differential media such as blood ager, McConky and manitol salt agar(MSA. Following incubation of media at 37c° for 24hr, bacterial species were identified using differential related tests. The isolated species were than antibiogramed and the results together with other data was analysed by SPSS software program. Results: Of the total of 134 cases, 81(60.4% were male and 53(39.6% female. The mean scrub time for each person was (206.1+/-103.2 seconds; 6 to 60 seconds base change. Increasing time of scrub was significantly correlated with decreasing rate of bacteria (P=0.003, (R=-0.254. Contamination was present in 129(96.3% cases following scrubbing. Maximum contamination was observed in nails (92.5%. Average number of bacteria for each individual was between 0 and 159. 62.6% of isolated bacteria were non- staphylococci and 7.7% were S. aureus. Vancomycin and ceftizoxim were the most sensitive, while penicillin was the least sensitive antibiotic. Conclusion: Results revealed that hand contamination was more than the expected standard level. Therefore, regarding the critical task of surgical personnel, training of all operation room staff is highly recommended to minimize the rate of contamination.

  14. Erwinia teleogrylli sp. nov., a Bacterial Isolate Associated with a Chinese Cricket.

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    Bo Liu

    Full Text Available A bacterial isolate (SCU-B244T was obtained in China from crickets (Teleogryllus occipitalis living in cropland deserted for approximately 10 years. The isolated bacteria were Gram-negative, facultatively anaerobic, oxidase-negative rods. A preliminary analysis of the 16S rRNA gene sequence indicated that the strain belongs to either the genus Erwinia or Pantoea. Analysis of multilocus sequence typing based on concatenated partial atpD, gyrB and infB gene sequences and physiological and biochemical characteristics indicated that the strain belonged to the genus Erwinia, as member of a new species as it was distinct from other known Erwinia species. Further analysis of the 16S rRNA gene showed SCU-B244T to have 94.71% identity to the closest species of that genus, Erwinia oleae (DSM 23398T, which is below the threshold of 97% used to discriminate bacterial species. DNA-DNA hybridization results (5.78±2.52% between SCU-B244T and Erwinia oleae (DSM 23398T confirmed that SCU-B244T and Erwinia oleae (DSM 23398T represent different species combined with average nucleotide identity values which range from 72.42% to 74.41. The DNA G+C content of SCU-B244T was 55.32 mol%, which also differs from that of Erwinia oleae (54.7 to 54.9 mol%. The polyphasic taxonomic approach used here confirmed that the strain belongs to the Erwinia group and represents a novel species. The name Erwinia teleogrylli sp. nov. is proposed for this novel taxon, for which the type strain is SCU-B244T (= CGMCC 1.12772T = DSM 28222T = KCTC 42022T.

  15. Isolation of Vermamoeba vermiformis and associated bacteria in hospital water.

    Science.gov (United States)

    Pagnier, Isabelle; Valles, Camille; Raoult, Didier; La Scola, Bernard

    2015-03-01

    To detect new potential pathogens in hospital water, we isolated free-living amoebae in water samples taken from three different hospitals in Marseille (France). The samples were inoculated in media containing saline buffer and various bacteria as nutrient sources. The isolated amoebae were identified by gene sequencing. Among the 105 water samples, taken from 19 sites, we isolated 14 amoebae, of which 9 Vermamoeba vermiformis and 5 Acanthamoeba sp. None of the amoebae showed the presence of obligate bacterial endosymbionts. Because V. vermiformis was most commonly isolated, we used an axenic collection strain to isolate amoeba-resistant bacteria from the same sites. The isolated bacterial species included Stenotrophomonas maltophilia and Legionella sp. Legionella taurinensis was isolated for the first time in association with amoebae. A strict intracellular bacterium was isolated, that may represent a new genus among the Chlamydiales. We propose that it be named "Candidatus Rubidus massiliensis". Our study shows that the isolation and identification of new pathogens associated with amoebae, which were previously performed using Acanthamoeba sp., should instead use V. vermiformis because this organism is more commonly associated with humans and is an essential complement of Acanthamoeba sp. co-culture to study the ecology of hospital water supplies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Potential of biosynthesized silver nanoparticles using Stenotrophomonas sp. BHU-S7 (MTCC 5978) for management of soil-borne and foliar phytopathogens.

    Science.gov (United States)

    Mishra, Sandhya; Singh, Braj Raj; Naqvi, Alim H; Singh, H B

    2017-03-27

    Stenotrophomonas sp. is emerging as a popular microbe of global concern with various potential ecological roles. Biosynthesis of gold and silver nanoparticles (AgNPs) using this bacterial strain has shown promising applications in life sciences. However, there is no report on efficient agricultural applications of biosynthesized AgNPs using Stenotrophomonas sp. In this regard, successful biosynthesis of AgNPs using Stenotrophomonas sp. BHU-S7 (MTCC 5978) was monitored by Uv-visible spectrum showing surface plasmon resonance (SPR) peak at 440 nm. The biosynthesized AgNPs were spherical with an average mean size of ~12 nm. The antifungal efficacy of biosynthesized AgNPs against foliar and soil-borne phytopathogens was observed. The inhibitory impact of AgNPs (2, 4, 10 μg/ml) on conidial germination was recorded under in vitro conditions. Interestingly, sclerotia of Sclerotium rolfsii exposed to AgNPs failed to germinate on PDA medium and in soil system. Moreover, AgNPs treatment successfully managed collar rot of chickpea caused by S. rolfsii under greenhouse conditions. The reduced sclerotia germination, phenolic acids induction, altered lignification and H 2 O 2 production was observed to be the probable mechanisms providing protection to chickpea against S. rolfsii. Our data revealed that AgNPs treated plants are better equipped to cope with pathogen challenge pointing towards their robust applications in plant disease management.

  17. Promising Biological Indicator of Heavy Metal Pollution: Bioluminescent Bacterial Strains Isolated and Characterized from Marine Niches of Goa, India.

    Science.gov (United States)

    Thakre, Neha A; Shanware, Arti S

    2015-09-01

    In present study, several marine water samples collected from the North Goa Beaches, India for isolation of luminescent bacterial species. Isolates obtained labelled as DP1-5 and AB1-6. Molecular characterization including identification of a microbial culture using 16S rRNA gene based molecular technique and phylogenetic analysis confirmed that DP3 & AB1 isolates were Vibrio harveyi. All of the isolates demonstrated multiple metal resistances in terms of growth, with altered luminescence with variable metal concentration. Present investigations were an attempt towards exploring and reporting an updated diversity of bioluminescent bacterial species from various sites around the Goa, India which would be explored in future for constructing luminescence based biosensor for efficiently monitoring the level of hazardous metals in the environment.

  18. Microbiological and molecular identification of bacterial species isolated from nasal and oropharyngeal mucosa of fuel workers in Riyadh,

    Directory of Open Access Journals (Sweden)

    Suaad S. AlWakeel

    2017-09-01

    Full Text Available This study aimed to determine the bacterial species colonizing the nasal and oropharyngeal mucosa of fuel workers in Central Riyadh, Saudi Arabia on a microbiological and molecular level. Throat and nasal swab samples were obtained from 29 fuel station attendants in the period of time extending from March to May 2014 in Riyadh, Saudi Arabia. Microbiological identification techniques were utilized to identify the bacterial species isolated. Antibiotic sensitivity was assessed for each of the bacterial isolates. Molecular identification techniques based on PCR analysis of specific genomic sequences was conducted and was the basis on which phylogeny representation was done for 10 randomly selected samples of the isolates. Blood was drawn and a complete blood count was conducted to note the hematological indices for each of the study participants. Nineteen bacterial species were isolated from both the nasal cavity and the oropharynx including Streptococcus thoraltensis, alpha-hemolytic streptococci, Staphylococcus hominis, coagulase-negative staphylococci, Leuconostoc mesenteroides, Erysipelothrix rhusiopathiae and several others. We found 100% sensitivity of the isolates to ciprofloxacin, cefuroxime and gentamicin. Whereas cefotaxime and azithromycin posted sensitivities of 85.7% and 91.4%, respectively. Low sensitivities (<60% sensitivity to the antibiotics ampicillin, erythromycin, clarithromycin and norfloxacin were observed. Ninety-seven percent similarity to the microbial bank species was noted when the isolates were compared to it. Most hematological indices recorded were within the normal range. In conclusion, exposure to toxic fumes and compounds within fuel products may be a contributing factor to bacterial colonization of the respiratory tract in fuel workers.

  19. Isolation, identification, and pathological effects of beach sand bacterial extract on human skin keratinocytesin vitro.

    Science.gov (United States)

    Subhan, Fazli; Shahzad, Raheem; Tauseef, Isfahan; Haleem, Kashif Syed; Rehman, Atta-Ur; Mahmood, Sajid; Lee, In-Jung

    2018-01-01

    Beaches are recreational spots for people. However, beach sand contains harmful microbes that affect human health, and there are no established methods for either sampling and identifying beach-borne pathogens or managing the quality of beach sand. This study was conducted with the aim of improving human safety at beaches and augmenting the quality of the beach experience. Beach sand was used as a resource to isolate bacteria due to its distinctive features and the biodiversity of the beach sand biota. A selected bacterial isolate termed FSRS was identified as Pseudomonas stutzeri using 16S rRNA sequencing and phylogenetic analysis, and the sequence was deposited in the NCBI GenBank database under the accession number MF599548. The isolated P. stutzeri bacterium was cultured in Luria-Bertani growth medium, and a crude extract was prepared using ethyl acetate to examine the potential pathogenic effect of P. stutzeri on human skin. A human skin keratinocyte cell line (HaCaT) was used to assess cell adhesion, cell viability, and cell proliferation using a morphological analysis and a WST-1 assay. The crude P. stutzeri extract inhibited cell adhesion and decreased cell viability in HaCaT cells. We concluded that the crude extract of P. stutzeri FSRS had a strong pathological effect on human skin cells. Beach visitors frequently get skin infections, but the exact cause of the infections is yet to be determined. The beach sand bacterium P. stutzeri may, therefore, be responsible for some of the dermatological problems experienced by people visiting the beach.

  20. Prevalence and antibiotic resistance of bacterial pathogens isolated from childhood diarrhoea in four provinces of Kenya.

    Science.gov (United States)

    Sang, Willie Kipkemboi; Oundo, Valerie; Schnabel, David

    2012-07-23

    Diarrhoea is one of the main causes of morbidity and mortality among children in sub-Saharan Africa, and one of the main causes of hospital admissions in rural areas of Kenya. In Kenya, antimicrobial resistance surveillance has been conducted only at the institutional levels, with limited sharing of information and analysis of data. As a result, the actual scale of regional or national antimicrobial drug resistance is not well defined. Stool samples were collected between 1 October 2007 and 30 September 2008 from a total of 651 outpatients with diarrhoea who were under five years of age in four provinces of Kenya.  Conventional, biochemical methods, multiplex PCR and antimicrobial susceptibility were conducted to identify the bacterial causes and virulence factors in the isolates, respectively.  Of the 651 patients screened, we identified the causes of 115 cases (17.7%) as follows: Pathogenic E. coli (11.2%) [enteroaggregative (8.9%), enterotoxigenic (1.2%), enteroinvasive (0.6%), shigatoxigenic (0.5%)], Salmonella (3.5%), Shigella (2%) and Vibrio cholera O1 (0.7%). The highest levels of resistance among the E. coli isolates were observed in ampicillin and trimethoprim/sulphamethoxazole each at 95% followed by tetracycline at 81%. Shigella isolate levels of resistance ranged from 80% to 100% for ampicillin, tetracycline and trimethoprim/sulphamethoxazole. The highest prevalence of antimicrobial resistance was to ampicillin followed by trimethoprim/sulphamethoxazole and tetracycline. Though still at low levels, the major concern from our findings is the emerging resistance of enteric pathogens that was observed to quinolones (ciprofloxacin, nalidixic acid, norfloxacin) and gentamycin.

  1. Towards Defining the Ecological Niches of Novel Coastal Gulf of Mexico Bacterial Isolates

    Science.gov (United States)

    Henson, M. W.; Thrash, C.; Nall, E.

    2016-02-01

    The study of microbial contributions to biogeochemistry is critical to understanding the cycles of fundamental compounds and gain predictive capabilities in a changing environment. Such study requires observation of microbial communities and genetics in nature, coupled with experimental testing of hypotheses both in situ and in laboratory settings. This study combines dilution-to-extinction based high-throughput culturing (HTC) with cultivation-independent and geochemical measurements to define potential ecological niches of novel bacterial isolates from the coastal northern Gulf of Mexico (cnGOM). Here we report findings from the first of a three-year project. In total, 43 cultures from seven HTC experiments were capable of being repeatedly transferred. Sanger sequencing of the 16S rRNA gene identified these isolates as belonging to the phyla Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, and Betaproteobacteria. Eight are being genome sequenced, with two selected for further physiological characterization due to their phylogenic novelty and potential ecological significance. Strain LSUCC101 likely represents a novel family of Gammaproteobacteria (best blast hit to a cultured representative showed 91% sequence identity) and strain LSUCC96 belongs to the OM252 clade, with the Hawaiian isolate HIMB30 as its closest relative. Both are small (0.3-0.5 µm) cocci. The environmental importance of both LSUCC101 and LSUCC96 was illustrated by their presence within the top 30 OTU0.03 of cnGOM 16S rRNA gene datasets as well as within clone libraries from coastal regions around the world. Ongoing work is determining growth efficiencies, substrate utilization profiles, and metabolic potential to elucidate the roles of these organisms in the cnGOM. Comparative genomics will examine the evolutionary divergence of these organisms from their closest neighbors, and metagenomic recruitment to genomes will help identify strain-based variation from different coastal regions.

  2. Isolation, identification, and pathological effects of beach sand bacterial extract on human skin keratinocytes in vitro

    Directory of Open Access Journals (Sweden)

    Fazli Subhan

    2018-01-01

    Full Text Available Background Beaches are recreational spots for people. However, beach sand contains harmful microbes that affect human health, and there are no established methods for either sampling and identifying beach-borne pathogens or managing the quality of beach sand. Method This study was conducted with the aim of improving human safety at beaches and augmenting the quality of the beach experience. Beach sand was used as a resource to isolate bacteria due to its distinctive features and the biodiversity of the beach sand biota. A selected bacterial isolate termed FSRS was identified as Pseudomonas stutzeri using 16S rRNA sequencing and phylogenetic analysis, and the sequence was deposited in the NCBI GenBank database under the accession number MF599548. The isolated P. stutzeri bacterium was cultured in Luria–Bertani growth medium, and a crude extract was prepared using ethyl acetate to examine the potential pathogenic effect of P. stutzeri on human skin. A human skin keratinocyte cell line (HaCaT was used to assess cell adhesion, cell viability, and cell proliferation using a morphological analysis and a WST-1 assay. Result The crude P. stutzeri extract inhibited cell adhesion and decreased cell viability in HaCaT cells. We concluded that the crude extract of P. stutzeri FSRS had a strong pathological effect on human skin cells. Discussion Beach visitors frequently get skin infections, but the exact cause of the infections is yet to be determined. The beach sand bacterium P. stutzeri may, therefore, be responsible for some of the dermatological problems experienced by people visiting the beach.

  3. ‘Lactomassilus timonensis,’ a new anaerobic bacterial species isolated from the milk of a healthy African mother

    Directory of Open Access Journals (Sweden)

    A.H. Togo

    2018-01-01

    Full Text Available We here report the main characteristics of a new anaerobic bacterial genus and species ‘Lactomassilus timonensis,’ strain Marseille-P4641T (CSUR = P4641, isolated by microbial culturomics from the milk of a 35-year-old healthy lactating mother from Mali.

  4. ‘Olegusella massiliensis’ strain KHD7, a new bacterial genus isolated from the female genital tract

    Directory of Open Access Journals (Sweden)

    K. Diop

    2016-07-01

    Full Text Available We report the main characteristics of ‘Olegusella massiliensis’ gen. nov., sp. nov., strain KHD7 (= CSUR P2268=DSM 101849, a new member of the Coriobacteriaceae family isolated from the vaginal flora of a patient with bacterial vaginosis.

  5. Stenotrophomonas maltophilia in Mexico: antimicrobial resistance, biofilm formation and clonal diversity.

    Science.gov (United States)

    Flores-Treviño, Samantha; Gutiérrez-Ferman, Jessica Lizzeth; Morfín-Otero, Rayo; Rodríguez-Noriega, Eduardo; Estrada-Rivadeneyra, Diego; Rivas-Morales, Catalina; Llaca-Díaz, Jorge M; Camacho-Ortíz, Adrián; Mendoza-Olazarán, Soraya; Garza-González, Elvira

    2014-11-01

    Stenotrophomonas maltophilia is an important multidrug-resistant nosocomial pathogen associated with high mortality. Our aim was to examine antimicrobial susceptibility, biofilm production and clonal relatedness of clinical isolates of S. maltophilia. S. maltophilia isolates were collected between 2006 and 2013 from two tertiary care hospitals in Mexico. Antimicrobial susceptibility was evaluated by the broth microdilution method. PCR was used to determine the presence of β-lactamase genes L1 and L2. Biofilm formation was assessed with crystal violet staining. Clonal relatedness was determined by PFGE. Among the 119 collected S. maltophilia isolates, 73 (61.3%) were from the respiratory tract. Resistance levels exceeded 75% for imipenem, meropenem, ampicillin, aztreonam, gentamicin and tobramycin. Resistance to trimethoprim-sulfamethoxazole was 32.8%. L1 and L2 genes were detected in 77.1% (91/118) and 66.9% (79/118) of isolates, respectively. All S. maltophilia strains were able to produce biofilms. Strains were classified as weak (47.9%, 57/119), moderate (38.7%, 46/119), or strong (13.4%, 16/119) biofilm producers. A total of 89 distinct PFGE types were identified and 21.6% (22/102) of the isolates were distributed in nine clusters. This is the first study in Mexico to reveal characteristics of clinical isolates of S. maltophilia. Clonal diversity data indicate low cross-transmission of S. maltophilia in a hospital setting. The high antibiotic resistance underscores the need for continuous surveillance of S. maltophilia in hospital settings in Mexico. © 2014 The Authors.

  6. Fermentative hydrogen production from hydrolyzed cellulosic feedstock prepared with a thermophilic anaerobic bacterial isolate

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung Chung [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Huang, Chi-Yu.; Fu, Tzu-Ning [Department of Environmental Engineering and Science, Tunghai University, Taichung 407 (China); Chen, Chun-Yen; Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China)

    2009-08-15

    Hydrogen gas was produced via dark fermentation from natural cellulosic materials and {alpha}-cellulose via a two-step process, in which the cellulosic substrates were first hydrolyzed by an isolated cellulolytic bacterium Clostridium strain TCW1, and the resulting hydrolysates were then used as substrate for fermentative H{sub 2} production. The TCW1 strain was able to hydrolyze all the cellulosic materials examined to produce reducing sugars (RS), attaining the best reducing sugar production yield of 0.65 g reducing sugar/g substrate from hydrolysis of {alpha}-cellulose. The hydrolysates of those cellulosic materials were successfully converted to H{sub 2} via dark fermentation using seven H{sub 2}-producing bacterial isolates. The bioH{sub 2} production performance was highly dependent on the type of cellulosic feedstock used, the initial reducing sugar concentration (C{sub RS,o}) (ranging from 0.7 to 4.5 mg/l), as well as the composition of sugar and soluble metabolites present in the cellulosic hydrolysates. It was found that Clostridium butyricum CGS5 displayed the highest H{sub 2}-producing efficiency with a cumulative H{sub 2} production of 270 ml/l from {alpha}-cellulose hydrolysate (C{sub RS,o} = 4.52 mg/l) and a H{sub 2} yield of 7.40 mmol/g RS (or 6.66 mmol/g substrate) from napier grass hydrolysate (C{sub RS,o} = 1.22 g/l). (author)

  7. Interspecies signalling via the Stenotrophomonas maltophilia diffusible signal factor influences biofilm formation and polymyxin tolerance in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Ryan, R.P.; Fouhy, Y.; Garcia, B.F.

    2008-01-01

    Interspecies signalling through the action of diffusible signal molecules can influence the behaviour of organisms growing in polymicrobial communities. Stenotrophomonas maltophilia and Pseudomonas aeruginosa occur ubiquitously in the environment and can be found together in diverse niches....... maltophilia and could be mimicked by the addition of synthetic DSF. This response of P. aeruginosa to DSF required PA1396, a sensor kinase with an input domain of related amino acid sequence to the sensory input domain of RpfC, which is responsible for DSF perception in xanthomonads. Mutation of PA1396...... or addition of DSF to P. aeruginosa led to increased levels of a number of proteins with roles in bacterial stress tolerance, including those implicated in resistance to cationic antimicrobial peptides. This effect was associated with increased tolerance to polymyxins. Homologues of PA1396 occur in a number...

  8. Indoleacetic acid production and plant growth promoting potential of bacterial endophytes isolated from rice (Oryza sativa L.) seeds.

    Science.gov (United States)

    Shahzad, Raheem; Waqas, Muhammad; Khan, Abdul Latif; Al-Hosni, Khadija; Kang, Sang-Mo; Seo, Chang-Woo; Lee, In-Jung

    2017-06-01

    Bacterial endophytes from the phyllosphere and rhizosphere have been used to produce bioactive metabolites and to promote plant growth. However, little is known about the endophytes residing in seeds. This study aimed to isolate and identify seed-borne bacterial endophytes from rice and elucidate their potential for phytohormone production and growth enhancement. The isolated endophytes included Micrococcus yunnanensis RWL-2, Micrococcus luteus RWL-3, Enterobacter soli RWL-4, Leclercia adecarboxylata RWL-5, Pantoea dispersa RWL-6, and Staphylococcus epidermidis RWL-7, which were identified using 16S rRNA sequencing and phylogenetic analysis. These strains were analyzed for indoleacetic acid (IAA) production by using GC-MS and IAA was found in the range of 11.50 ± 0.77 μg ml -1 to 38.80 ± 1.35 μg ml -1 . We also assessed the strains for plant growth promoting potential because these isolates were able to produce IAA in pure culture. Most of the growth attributes of rice plants (shoot and root length, fresh and dry biomass, and chlorophyll content) were significantly increased by bacterial endophytes compared to the controls. These results show that IAA producing bacterial endophytes can improve hostplant growth traits and can be used as bio-fertilizers.

  9. Monitoring of oil pollution at Gemsa Bay and bioremediation capacity of bacterial isolates with biosurfactants and nanoparticles.

    Science.gov (United States)

    El-Sheshtawy, H S; Khalil, N M; Ahmed, W; Abdallah, R I

    2014-10-15

    Fifteen crude oil-degrading bacterial isolates were isolated from an oil-polluted area in Gemsa Bay, Red Sea, Egypt. Two bacterial species showed the highest growth rate on crude oil hydrocarbons. From an analysis of 16S rRNA sequences, these isolates were identified as Pseudomonas xanthomarina KMM 1447 and Pseudomonas stutzeri ATCC 17588. Gas Chromatographic (GC) analysis of the crude oil remaining in the culture medium after one week at 30°C showed that the optimum biodegradation of crude petroleum oil was demonstrated at 50% in medium containing biosurfactant with two types of nanoparticles separately and two bacterial species. The complete degradation of some different members of polyaromatics and the percentage biodegradation of other polyaromatics increased in microcosm containing two different types of nanoparticles with biosurfactant after 7 days. In conclusion, these bacterial strains may be useful for the bioremediation process in the Gemsa Bay, Red Sea decreasing oil pollution in this marine ecosystem. Copyright © 2014 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. In silico design of PHA synthase and its validation by PHAs producing bacterial isolates

    Directory of Open Access Journals (Sweden)

    Susrita Sahoo

    2017-10-01

    Full Text Available Biopolymers are important alternatives to the petroleum-based plastics due to environment friendly manufacturing processes, biodegradability and biocompatibility. Therefore use of novel biopolymers such as polylactide, polysaccharides, aliphatic polyesters and polyhydroxyalkonoates (PHAs is of interest. PHAs are biodegradable polyesters of hydroxyalkanoates (HA produced from renewable resources by using microorganisms as intracellular carbon and energy storage compounds.  Even though PHAs are promising candidate for biodegradable polymers, however, the production cost limits their application on an industrial scale. Therefore an attempt was made to model different PHAs synthases which are the key enzyme in the biosynthesis of Polyhydroxyalkanoates as the structural information of this enzyme is in dark veil.Then molecular docking  of class I  PHA  Synthase from Ralstonia Eutrophia was done to study the PHA synthase activity. As there are lots of strain which needs to explore for the production of PHA. This investigation leads to find out the most industrial applicable microbes. Few bacterial isolates from soil sample were screened for production of PHA followed by the validation of the enzymatic activity and its product characterization to understand its structural properties.

  12. Comparative Genomics of Facultative Bacterial Symbionts Isolated from European Orius Species Reveals an Ancestral Symbiotic Association

    Directory of Open Access Journals (Sweden)

    Xiaorui Chen

    2017-10-01

    Full Text Available Pest control in agriculture employs diverse strategies, among which the use of predatory insects has steadily increased. The use of several species within the genus Orius in pest control is widely spread, particularly in Mediterranean Europe. Commercial mass rearing of predatory insects is costly, and research efforts have concentrated on diet manipulation and selective breeding to reduce costs and improve efficacy. The characterisation and contribution of microbial symbionts to Orius sp. fitness, behaviour, and potential impact on human health has been neglected. This paper provides the first genome sequence level description of the predominant culturable facultative bacterial symbionts associated with five Orius species (O. laevigatus, O. niger, O. pallidicornis, O. majusculus, and O. albidipennis from several geographical locations. Two types of symbionts were broadly classified as members of the genera Serratia and Leucobacter, while a third constitutes a new genus within the Erwiniaceae. These symbionts were found to colonise all the insect specimens tested, which evidenced an ancestral symbiotic association between these bacteria and the genus Orius. Pangenome analyses of the Serratia sp. isolates offered clues linking Type VI secretion system effector–immunity proteins from the Tai4 sub-family to the symbiotic lifestyle.

  13. Effect of gut bacterial isolates fromApis mellifera jemeniticaonPaenibacillus larvaeinfected bee larvae.

    Science.gov (United States)

    Al-Ghamdi, Ahmad; Ali Khan, Khalid; Javed Ansari, Mohammad; Almasaudi, Saad B; Al-Kahtani, Saad

    2018-02-01

    The probiotic effects of seven newly isolated gut bacteria, from the indegenous honey bees of Saudi Arabia were investigated. In vivo bioassays were used to investigate the effects of each gut bacterium namely, Fructobacillus fructosus (T1), Proteus mirabilis (T2), Bacillus licheniformis (T3), Lactobacillus kunkeei (T4), Bacillus subtilis (T5), Enterobacter kobei (T6), and Morganella morganii (T7) on mortality percentage of honey bee larvae infected with P. larvae spores along with negative control (normal diet) and positive control (normal diet spiked with P. larvae spores). Addition of gut bacteria to the normal diet significantly reduced the mortality percentage of the treated groups. Mortality percentage in all treated groups ranged from 56.67% up to 86.67%. T6 treated group exhibited the highest mortality (86.67%), whereas T4 group showed the lowest mortality (56.67%). Among the seven gut bacterial treatments, T4 and T3 decreased the mortality 56.67% and 66.67%, respectively, whereas, for T2, T6, and T7 the mortality percentage was equal to that of the positive control (86.67%). Mortality percentages in infected larval groups treated with T1, and T5 were 78.33% and 73.33% respectively. Most of the mortality occurred in the treated larvae during days 2 and 3. Treatments T3 and T4 treatments showed positive effects and reduced mortality.

  14. Effect of gut bacterial isolates from Apis mellifera jemenitica on Paenibacillus larvae infected bee larvae

    Directory of Open Access Journals (Sweden)

    Ahmad Al-Ghamdi

    2018-02-01

    Full Text Available The probiotic effects of seven newly isolated gut bacteria, from the indegenous honey bees of Saudi Arabia were investigated. In vivo bioassays were used to investigate the effects of each gut bacterium namely, Fructobacillus fructosus (T1, Proteus mirabilis (T2, Bacillus licheniformis (T3, Lactobacillus kunkeei (T4, Bacillus subtilis (T5, Enterobacter kobei (T6, and Morganella morganii (T7 on mortality percentage of honey bee larvae infected with P. larvae spores along with negative control (normal diet and positive control (normal diet spiked with P. larvae spores. Addition of gut bacteria to the normal diet significantly reduced the mortality percentage of the treated groups. Mortality percentage in all treated groups ranged from 56.67% up to 86.67%. T6 treated group exhibited the highest mortality (86.67%, whereas T4 group showed the lowest mortality (56.67%. Among the seven gut bacterial treatments, T4 and T3 decreased the mortality 56.67% and 66.67%, respectively, whereas, for T2, T6, and T7 the mortality percentage was equal to that of the positive control (86.67%. Mortality percentages in infected larval groups treated with T1, and T5 were 78.33% and 73.33% respectively. Most of the mortality occurred in the treated larvae during days 2 and 3. Treatments T3 and T4 treatments showed positive effects and reduced mortality.

  15. Increasing antibiotic resistance in preservative-tolerant bacterial strains isolated from cosmetic products.

    Science.gov (United States)

    Orús, Pilar; Gomez-Perez, Laura; Leranoz, Sonia; Berlanga, Mercedes

    2015-03-01

    To ensure the microbiological quality, consumer safety and organoleptic properties of cosmetic products, manufacturers need to comply with defined standards using several preservatives and disinfectants. A drawback regarding the use of these preservatives is the possibility of generating cross-insusceptibility to other disinfectants or preservatives, as well as cross resistance to antibiotics. Therefore, the objective of this study was to understand the adaptive mechanisms of Enterobacter gergoviae, Pseudomonas putida and Burkholderia cepacia that are involved in recurrent contamination in cosmetic products containing preservatives. Diminished susceptibility to formaldehyde-donors was detected in isolates but not to other preservatives commonly used in the cosmetics industry, although increasing resistance to different antibiotics (β-lactams, quinolones, rifampicin, and tetracycline) was demonstrated in these strains when compared with the wild-type strain. The outer membrane protein modifications and efflux mechanism activities responsible for the resistance trait were evaluated. The development of antibiotic-resistant microorganisms due to the selective pressure from preservatives included in cosmetic products could be a risk for the emergence and spread of bacterial resistance in the environment. Nevertheless, the large contribution of disinfection and preservation cannot be denied in cosmetic products. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  16. Whole-Genome Sequencing and Concordance Between Antimicrobial Susceptibility Genotypes and Phenotypes of Bacterial Isolates Associated with Bovine Respiratory Disease

    Directory of Open Access Journals (Sweden)

    Joseph R. Owen

    2017-09-01

    Full Text Available Extended laboratory culture and antimicrobial susceptibility testing timelines hinder rapid species identification and susceptibility profiling of bacterial pathogens associated with bovine respiratory disease, the most prevalent cause of cattle mortality in the United States. Whole-genome sequencing offers a culture-independent alternative to current bacterial identification methods, but requires a library of bacterial reference genomes for comparison. To contribute new bacterial genome assemblies and evaluate genetic diversity and variation in antimicrobial resistance genotypes, whole-genome sequencing was performed on bovine respiratory disease–associated bacterial isolates (Histophilus somni, Mycoplasma bovis, Mannheimia haemolytica, and Pasteurella multocida from dairy and beef cattle. One hundred genomically distinct assemblies were added to the NCBI database, doubling the available genomic sequences for these four species. Computer-based methods identified 11 predicted antimicrobial resistance genes in three species, with none being detected in M. bovis. While computer-based analysis can identify antibiotic resistance genes within whole-genome sequences (genotype, it may not predict the actual antimicrobial resistance observed in a living organism (phenotype. Antimicrobial susceptibility testing on 64 H. somni, M. haemolytica, and P. multocida isolates had an overall concordance rate between genotype and phenotypic resistance to the associated class of antimicrobials of 72.7% (P < 0.001, showing substantial discordance. Concordance rates varied greatly among different antimicrobial, antibiotic resistance gene, and bacterial species combinations. This suggests that antimicrobial susceptibility phenotypes are needed to complement genomically predicted antibiotic resistance gene genotypes to better understand how the presence of antibiotic resistance genes within a given bacterial species could potentially impact optimal bovine respiratory

  17. Protocol for Evaluating the Permissiveness of Bacterial Communities Toward Conjugal Plasmids by Quantification and Isolation of Transconjugants

    DEFF Research Database (Denmark)

    Klümper, Uli; Dechesne, Arnaud; Smets, Barth F.

    2014-01-01

    The transfer of conjugal plasmids is the main bacterial process of horizontal gene transfer to potentially distantly related bacteria. These extrachromosomal, circular DNA molecules host genes that code for their own replication and transfer to other organisms. Because additional accessory genes...... of a microbial community able to receive an introduced plasmid at both quantitative and phylogenetic levels. In this chapter, we describe a protocol for simultaneous quantification of plasmid transfer frequency to and high-throughput isolation of transconjugants from a mixed bacterial community after introducing...

  18. Intraabdominal abscess caused by Stenotrophomonas maltophilia: A case report

    Directory of Open Access Journals (Sweden)

    Toyomitsu Sawai

    Full Text Available Introduction: Stenotrophomonas maltophilia usually causes nosocomial infections, but intraabdominal abscesses or organ/space surgical site infection (SSI secondary to this organism has been rarely reported. Here, we reported a rare case of SSI that presented as intraabdominal abscess caused by S. maltophilia. Presentation of case: A 68-year-old woman presented to our hospital with transverse colon cancer. Further work up with abdominal computed tomography (CT revealed left renal cell carcinoma. Transverse colon resection and left kidney partial resection were performed. On post-operative day 10, she started to have fever at 38 °C and repeat abdominal CT showed intraabdominal abscess. Empiric treatment with piperacillin/tazobactam (TAZ/PIPC was initiated. However, fever persisted and the abscess size did not change despite 10 days of antibiotic. On post-operative day 20, drainage of intraabdominal abscess was performed. TAZ/PIPC was then shifted to meropenem (MEPM. After two days, S. maltophilia was identified in the culture of the abscess, and MEPM was shifted to minocycline (MINO. Fever disappeared after 7 days of treatment and abdominal CT after 14 days showed almost complete resolution of the abscess. Discussion: S. maltophilia is a multi-drug resistant, aerobic, non-glucose fermenting, non-sporulating, Gram-negative bacillus. S. maltophilia may cause a variety of infections, but intraabdominal abscesses as a manifestation of SSI due to this organism is relative rare. Conclusion: Although usually a non-pathogenic organism or colonizer, S. maltophilia can cause organ/space SSI in an immunocompromised host. Therefore, clinicians should be aware of the possibility that S. maltophilia may cause organ/space SSI. Keywords: Stenotrophomonas maltophilia, Intraabdominal abscess, Surgical site infections

  19. Indagine epidemiologica locale sulle infezioni sostenute da Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia cepacia e sensibilità agli antibiotici di questi microrganismi.

    Directory of Open Access Journals (Sweden)

    Valeria Di Marcello

    2007-03-01

    Full Text Available Background: The aim of this local surveillance study was to determine the distribution of Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia cepacia in our geographic area, their impact in the hospital and community acquired infections and their resistance to antimicrobial agents currently used in the treatment of infections due to these microrganisms. Materials and Methods: During the period January 2001 - June 2003, 14.200 clinical isolates were collected from urine,wounds, catheters, body fluids, blood, respiratory tract specimens. Bacterial identifications were performed according to the standard methods (Murray, 2003 and antibiotic susceptibility tests were carry out in microassay by the automated system MicroScan (Dade Behring, Milano, Italy.The following antimicrobial agents were tested: piperacillin (PIP, ticarcillin (TIC, piperacillin-tazobactam (TZP, ticarcillin-clavulanic acid (TTC, ceftazidime (CAZ, ceftriaxone (CRO, aztreonam (ATM, imipenem (IPM, trimethoprim-sulfamethoxazole (SXT, gentamicin (CN, amikacin (AK, tobramycin (TOB, ciprofloxacin (CIP. Results: A total of 994 Pseudomonadaceae were isolated from in- (67% and out-patients (33%.They were P.aeruginosa (81%, other Pseudomonas species as P.fluorescens and P.putida (8%, S.maltophilia (9% and B.cepacia (2%.The great majority of the strains were collected from respiratory tract specimens (70% and urine (15%.The divisions from which derived the greater quantity of isolates were pediatric (33.8%, intensive care (22.7% and pneumology (10% units.Antibiotics more active against P. aeruginosa were IPM, CAZ,AK and TZP. IPM was effective against B. cepacia also.The other drugs, except SXT, displayed against this microrganism high rates of resistance. Even S. maltophilia was not susceptible to much antimicrobial agents, whereas SXT was the drug more active against this germ. Conclusion: P. aeruginosa was the microrganism more frequently isolated among non-fermenting Gram

  20. Acanthamoeba and Stenotrophomonas maltophilia keratitis with fungal keratitis in the contralateral eye

    Directory of Open Access Journals (Sweden)

    Thomas F Mauger

    2010-10-01

    Full Text Available Thomas F Mauger, Rebecca Ann Kuennen, Reynell Harder Smith, William SawyerDepartment of Ophthalmology, The Ohio State University, Columbus, OH, USAPurpose: The purpose of this study is to describe the diagnosis, course, and outcome of a case of Acanthamoeba and Stenotrophomonas keratitis with a fungal keratitis in the contralateral eye.Methods: A case of Acanthamoeba and Stenotrophomonas keratitis was diagnosed with confocal microscopy and cultures with confocal diagnosis of fungal keratitis in the fellow eye.Results: During the initial treatment of the Acanthamoeba and Stenotrophomonas keratitis, the contralateral eye developed a keratitis that demonstrated hyphae in the corneal stroma with confocal microscopy consistent with fungal keratitis.Conclusions: Bilateral chronic keratitis cannot be assumed to be caused by the same organism and independent cultures, and confocal microscopy needs to be performed to direct appropriate therapy.Keywords: Acanthamoeba, Stenotrophomonas, confocal, fungus, keratitis

  1. Isolation and partial characterization of bacterial strains on low organic carbon medium from soils fertilized with different organic amendments.

    Science.gov (United States)

    Senechkin, Ilya V; Speksnijder, Adrianus G C L; Semenov, Alexander M; van Bruggen, Ariena H C; van Overbeek, Leonard S

    2010-11-01

    A total of 720 bacterial strains were isolated from soils with four different organic amendment regimes on a low organic carbon (low-C) agar medium (10 µg C ml(-1)) traditionally used for isolation of oligotrophs. Organic amendments in combination with field history resulted in differences in dissolved organic carbon contents in these soils. There were negative correlations between total and dissolved organic carbon content and the number of isolates on low-C agar medium, whereas these correlations were absent for bacterial strains isolated from the same soil on high-C agar medium (1,000 µg C ml(-1)). Repeated transfers (up to ten times) of the isolates from low-C agar medium to fresh low- and high-C agar media were done to test for exclusive growth under oligotrophic conditions. The number of isolates exclusively growing under oligotrophic conditions dropped after each subsequent transfer from 241 after the first to 98 after the third transfer step. Identification on the basis of partial 16S rRNA gene sequences revealed that most of the 241 isolates (as well as the subset of 98 isolates) belong to widespread genera such as Streptomyces, Rhizobium, Bradyrhizobium, and Mesorhizobium, and the taxonomic composition of dominant genera changed from the first transfer step to the third. A selected subset of 17 isolates were further identified and characterized for exclusive growth on low-C agar medium. Two isolates continued to grow only on low-C agar medium up to the tenth transfer step and matched most closely with Rhizobium sullae and an uncultured bacterium on the basis of the almost full-length 16S rRNA gene. It was concluded that the vast majority of strains which are isolated on low-C agar media belong to the trophic group of microorganisms adapted to a "broad range" of carbon concentrations, including well-known and widespread bacterial genera. Oligotrophy is a physiological, not a taxonomic property, and can only be identified by cultural means so far. We

  2. Ionome changes in Xylella fastidiosa-infected Nicotiana tabacum correlate with virulence and discriminate between subspecies of bacterial isolates.

    Science.gov (United States)

    Oliver, J E; Sefick, S A; Parker, J K; Arnold, T; Cobine, P A; De La Fuente, L

    2014-10-01

    Characterization of ionomes has been used to uncover the basis of nutrient utilization and environmental adaptation of plants. Here, ionomic profiles were used to understand the phenotypic response of a plant to infection by genetically diverse isolates of Xylella fastidiosa, a gram-negative, xylem-limited bacterial plant pathogen. In this study, X. fastidiosa isolates were used to infect a common model host (Nicotiana tabacum 'SR1'), and leaf and sap concentrations of eleven elements together with plant colonization and symptoms were assessed. Multivariate statistical analysis revealed that changes in the ionome were significantly correlated with symptom severity and bacterial populations in host petioles. Moreover, plant ionome modification by infection could be used to differentiate the X. fastidiosa subspecies with which the plant was infected. This report establishes host ionome modification as a phenotypic response to infection.

  3. Biodegradation of malathion, α- and β-endosulfan by bacterial strains isolated from agricultural soil in Veracruz, Mexico.

    Science.gov (United States)

    Jimenez-Torres, Catya; Ortiz, Irmene; San-Martin, Pablo; Hernandez-Herrera, R Idalia

    2016-12-01

    The objective of this study was to evaluate the capacity of two bacterial strains isolated, cultivated, and purified from agricultural soils of Veracruz, Mexico, for biodegradation and mineralisation of malathion (diethyl 2-(dimethoxyphosphorothioyl) succinate) and α- and β-endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6-9-methano-2,4,3-benzodioxathiepine-3-oxide). The isolated bacterial strains were identified using biochemical and morphological characterization and the analysis of their 16S rDNA gene, as Enterobacter cloacae strain PMM16 (E1) and E. amnigenus strain XGL214 (M1). The E1 strain was able to degrade endosulfan, whereas the M1 strain was capable of degrading both pesticides. The E1 strain degraded 71.32% of α-endosulfan and 100% of β-endosulfan within 24 days. The absence of metabolites, such as endosulfan sulfate, endosulfan lactone, or endosulfan diol, would suggest degradation of endosulfan isomers through non-oxidative pathways. Malathion was completely eliminated by the M1 strain. The major metabolite was butanedioic acid. There was a time-dependent increase in bacterial biomass, typical of bacterial growth, correlated with the decrease in pesticide concentration. The CO 2 production also increased significantly with the addition of pesticides to the bacterial growth media, demonstrating that, under aerobic conditions, the bacteria utilized endosulfan and malathion as a carbon source. Here, two bacterial strains are shown to metabolize two toxic pesticides into non-toxic intermediates.

  4. Pattern of Bacterial Pathogens and Their Susceptibility Isolated from Surgical Site Infections at Selected Referral Hospitals, Addis Ababa, Ethiopia

    Directory of Open Access Journals (Sweden)

    Walelign Dessie

    2016-01-01

    Full Text Available Background. The emergence of multidrug resistant bacterial pathogens in hospitals is becoming a challenge for surgeons to treat hospital acquired infections. Objective. To determine bacterial pathogens and drug susceptibility isolated from surgical site infections at St. Paul Specialized Hospital Millennium Medical College and Yekatit 12 Referral Hospital Medical College, Addis Ababa, Ethiopia. Methods. A cross-sectional study was conducted between October 2013 and March 2014 on 107 surgical site infected patients. Wound specimens were collected using sterile cotton swab and processed as per standard operative procedures in appropriate culture media; and susceptibility testing was done using Kirby-Bauer disc diffusion technique. The data were analyzed by using SPSS version 20. Result. From a total of 107 swabs collected, 90 (84.1% were culture positive and 104 organisms were isolated. E. coli (24 (23.1% was the most common organism isolated followed by multidrug resistant Acinetobacter species (23 (22.1%. More than 58 (75% of the Gram negative isolates showed multiple antibiotic resistance (resistance ≥ 5 drugs. Pan-antibiotic resistance was noted among 8 (34.8% Acinetobacter species and 3 (12.5% E. coli. This calls for abstinence from antibiotic abuse. Conclusion. Gram negative bacteria were the most important isolates accounting for 76 (73.1%. Ampicillin, amoxicillin, penicillin, cephazoline, and tetracycline showed resistance while gentamicin and ciprofloxacin were relatively effective antimicrobials.

  5. Diversity, Bacterial Symbionts and Antibacterial Potential of Gut-Associated Fungi Isolated from the Pantala flavescens Larvae in China.

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    Ming-Wei Shao

    Full Text Available The diversity of fungi associated with the gut of Pantala flavescens larvae was investigated using a culture-dependent method and molecular identification based on an analysis of the internally transcribed spacer sequence. In total, 48 fungal isolates were obtained from P. flavescens larvae. Based on phylogenetic analyses, the fungal isolates were grouped in 5 classes and 12 different genera. Fourteen bacterial 16S rDNA sequences derived from total genomic DNA extractions of fungal mycelia were obtained. The majority of the sequences were associated with Proteobacteria (13/14, and one Bacillaceae (1/14 was included. Leclercia sp., Oceanobacillus oncorhynchi and Methylobacterium extorquens, were reported for the first time as bacterial endosymbionts in fungi. High-performance liquid chromatography (HPLC analysis indicated that bacterial symbionts produced specific metabolites and also exerted an inhibitory effect on fungal metabolites. The biological activity of the fungal culture extracts against the pathogenic bacteria Staphylococcus aureus (ATCC 6538, Bacillus subtilis (ATCC 6633 and Escherichia coli (ATCC 8739 was investigated, and 20 extracts (42% exhibited antibacterial activity against at least one of the tested bacterial strains. This study is the first report on the diversity and antibacterial activity of symbiotic fungi residing in the gut of P. flavescens larvae, and the results show that these fungi are highly diverse and could be exploited as a potential source of bioactive compounds.

  6. Surviving chytridiomycosis: differential anti-Batrachochytrium dendrobatidis activity in bacterial isolates from three lowland species of Atelopus.

    Directory of Open Access Journals (Sweden)

    Sandra V Flechas

    Full Text Available In the Neotropics, almost every species of the stream-dwelling harlequin toads (genus Atelopus have experienced catastrophic declines. The persistence of lowland species of Atelopus could be explained by the lower growth rate of Batrachochytrium dendrobatidis (Bd at temperatures above 25 °C. We tested the complementary hypothesis that the toads' skin bacterial microbiota acts as a protective barrier against the pathogen, perhaps delaying or impeding the symptomatic phase of chytridiomycosis. We isolated 148 cultivable bacterial strains from three lowland Atelopus species and quantified the anti-Bd activity through antagonism assays. Twenty-six percent (38 strains representing 12 species of the bacteria inhibited Bd growth and just two of them were shared among the toad species sampled in different localities. Interestingly, the strongest anti-Bd activity was measured in bacteria isolated from A. elegans, the only species that tested positive for the pathogen. The cutaneous bacterial microbiota is thus likely a fitness-enhancing trait that may (adaptation or not (exaptation have appeared because of natural selection mediated by chytridiomycosis. Our findings reveal bacterial strains for development of local probiotic treatments against chytridiomycosis and also shed light on the mechanisms behind the frog-bacteria-pathogen interaction.

  7. Plant-bacteria interactions: identification, characterization and localization of beneficial bacterial endophytes isolated from Vitis vinifera cv. Glera

    OpenAIRE

    Nigris, Sebastiano

    2015-01-01

    This thesis reports the results obtained during the three years PhD course focused on the study of culturable bacterial endophytes of Vitis vinifera Glera and their beneficial activities. The study, part of a large project named “EndoFlorVit project” (FEARS-UE and Regione Del Veneto), aims at investigate the biodiversity and the plant growth promoting activities of culturable endophytes isolated from Glera grapevine in vineyards of Conegliano-Valdobbiadene DOCG production area. This thesis re...

  8. Bacterial microflora isolated from the bark surface of poplars growing in areas where air pollution is very high

    Directory of Open Access Journals (Sweden)

    Krystyna Przybył

    2015-01-01

    Full Text Available In the autumn of 1976 bacteria of the genera Bacillus, Pseudomonas, Flavobacterium, Erwinia and Cellulomonas were isolated from the bark surface of poplars growing in protective belts around several industrial plants. It was found that the qualitative and quantitative composition of the surface bacterial microflora changes in dependence on the degree of resistance of the poplars to the action of the dust emitted by the industrial establishment and containing high amounts of heavy metals.

  9. Culturable bacterial endophytes isolated from Mangrove tree (Rhizophora apiculata Blume) enhance seedling growth in Rice

    OpenAIRE

    Deivanai, Subramanian; Bindusara, Amitraghata Santhanam; Prabhakaran, Guruswamy; Bhore, Subhash Janardhan

    2014-01-01

    Background: Endophytic bacteria do have several potential applications in medicine and in other various sectors of biotechnology including agriculture. Bacterial endophytes need to be explored for their potential applications in agricultural biotechnology. One of the potential applications of bacterial endophytes in agricultural is to enhance the growth of the agricultural crops. Hence, this study was undertaken to explore the plant growth promoting potential application of bacterial endophyt...

  10. Efficacy of fresh leaf extracts of Spondias mombin against some clinical bacterial isolates from typhoid patients

    Directory of Open Access Journals (Sweden)

    Olukemi Aromolaran

    2014-12-01

    Full Text Available Objective: To evaluate the phytochemical properties and antibacterial activity of methanol, acetone, ethanol and aqueous extracts of fresh leaves of Spondias mombin (S. mombin on some clinical bacterial isolates. Methods: Clean and fresh leaves of S. mombin were collected in Ondo, Southwestern Nigeria. The leaves were blended, extracted with methanol, acetone, ethanol and water. The extracts were evaporated to dryness using rotary evaporator and tested for the presence of saponins, tannins, cardiac glycoside, terpenoids, flavonoids, reducing sugars, volatile oils, alkaloids and glycoside. The extract were tested against Gram-negative bacteria Klebsiella pneumonia, Serratia marcescens, Salmonella typhi and Enterobacter aerogens; Gram-positive bacteria Staphylococcus aureus by observing the zones of inhibition using agar well diffusion assay. Results: The study showed that the leaves contained saponins, tannins, flavonoids, alkaloids and glycoside. All the solvent extracts showed activity against all the test bacteria. The methanol extract also showed the highest activity against Enterobacter aerogens, zone of diameter (15.00 依1.89 mm, while the ethanol extract showed the highest activity against Staphylococcus aureus with zone of diameter (12.50依1.50 mm. The acetone extract showed the highest activity against Salmonella typhi, zone of diameter (17.50依0.29 mm followed by methanol extract showing zone of diameter (15.67依1.01 mm. The acetone extract showed the highest activity against Klebsiella pneumonia (15.17依0.67 mm, while the aqueous extract shows the highest activity against Serratia marcescens (14.67依2.68 mm. The minimum inhibitory concentration of the leaf extracts ranged between 10-90 mg/mL. Conclusions: This study showed that the aqueous and organic solvents extract of fresh leaves of S. mombin has anti-microbial activity against all the tested organisms.

  11. Resistance trends among clinical isolates in China reported from CHINET surveillance of bacterial resistance, 2005-2014.

    Science.gov (United States)

    Hu, F-P; Guo, Y; Zhu, D-M; Wang, F; Jiang, X-F; Xu, Y-C; Zhang, X-J; Zhang, C-X; Ji, P; Xie, Y; Kang, M; Wang, C-Q; Wang, A-M; Xu, Y-H; Shen, J-L; Sun, Z-Y; Chen, Z-J; Ni, Y-X; Sun, J-Y; Chu, Y-Z; Tian, S-F; Hu, Z-D; Li, J; Yu, Y-S; Lin, J; Shan, B; Du, Y; Han, Y; Guo, S; Wei, L-H; Wu, L; Zhang, H; Kong, J; Hu, Y-J; Ai, X-M; Zhuo, C; Su, D-H; Yang, Q; Jia, B; Huang, W

    2016-03-01

    With the aim of gathering temporal trends on bacterial epidemiology and resistance from multiple laboratories in China, the CHINET surveillance system was organized in 2005. Antimicrobial susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method or automated systems. Results were analyzed according to Clinical and Laboratory Standards Institute (CLSI) 2014 definitions. Between 2005 and 2014, the number of bacterial isolates ranged between 22,774 and 84,572 annually. Rates of extended-spectrum β-lactamase production among Escherichia coli isolates were stable, between 51.7 and 55.8%. Resistance of E. coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, piperacillin/tazobactam and cefoperazone/sulbactam decreased with time. Carbapenem resistance among K. pneumoniae isolates increased from 2.4 to 13.4%. Resistance of Pseudomonas aeruginosa strains against all of antimicrobial agents tested including imipenem and meropenem decreased with time. On the contrary, resistance of Acinetobacter baumannii strains to carbapenems increased from 31 to 66.7%. A marked decrease of methicillin resistance from 69% in 2005 to 44.6% in 2014 was observed for Staphylococcus aureus. Carbapenem resistance rates in K. pneumoniae and A. baumannii in China are high. Our results indicate the importance of bacterial surveillance studies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Biocontrol of Sugarcane Smut Disease by Interference of Fungal Sexual Mating and Hyphal Growth Using a Bacterial Isolate.

    Science.gov (United States)

    Liu, Shiyin; Lin, Nuoqiao; Chen, Yumei; Liang, Zhibin; Liao, Lisheng; Lv, Mingfa; Chen, Yufan; Tang, Yingxin; He, Fei; Chen, Shaohua; Zhou, Jianuan; Zhang, Lianhui

    2017-01-01

    Sugarcane smut is a fungal disease caused by Sporisorium scitamineum , which can cause severe economic losses in sugarcane industry. The infection depends on the mating of bipolar sporida to form a dikaryon and develops into hyphae to penetrate the meristematic tissue of sugarcane. In this study, we set to isolate bacterial strains capable of blocking the fungal mating and evaluate their potential in control of sugarcane smut disease. A bacterial isolate ST4 from rhizosphere displayed potent inhibitory activity against the mating of S. scitamineum bipolar sporida and was selected for further study. Phylogenetic analyses and biochemical characterization showed that the isolate was most similar to Pseudomonas guariconensis . Methanol extracts from minimum and potato dextrose agar (PDA) agar medium, on which strain ST4 has grown, showed strong inhibitory activity on the sexual mating of S. scitamineum sporida, without killing the haploid cells MAT-1 or MAT-2. Further analysis showed that only glucose, but not sucrose, maltose, and fructose, could support strain ST4 to produce antagonistic chemicals. Consistent with the above findings, greenhouse trials showed that addition of 2% glucose to the bacterial inoculum significantly increased the strain ST4 biocontrol efficiency against sugarcane smut disease by 77% than the inoculum without glucose. The results from this study depict a new strategy to screen for biocontrol agents for control and prevention of the sugarcane smut disease.

  13. 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.

  14. Qualitative toxicity assessment of silver nanoparticles on the fresh water bacterial isolates and consortium at low level of exposure concentration.

    Science.gov (United States)

    Kumar, Deepak; Kumari, Jyoti; Pakrashi, Sunandan; Dalai, Swayamprava; Raichur, Ashok M; Sastry, T P; Mandal, A B; Chandrasekaran, N; Mukherjee, Amitava

    2014-10-01

    Silver nanoparticles (AgNPs) pose a high risk of exposure to the natural environment owing to their extensive usage in various consumer products. In the present study we attempted to understand the harmful effect of AgNPs at environmentally relevant low concentration levels (≤1ppm) towards two different freshwater bacterial isolates and their consortium. The standard plate count assay suggested that the AgNPs were toxic towards the fresh water bacterial isolates as well as the consortium, though toxicity was significantly reduced for the cells in the consortium. The oxidative stress assessment and membrane permeability studies corroborated with the toxicity data. The detailed electron microscopic studies suggested the cell degrading potential of the AgNPs, and the FT-IR studies confirmed the involvement of the surface groups in the toxic effects. No significant ion leaching from the AgNPs was observed at the applied concentration levels signifying the dominant role of the particle size, and size distribution in bacterial toxicity. The reduced toxicity for the cells in the consortium than the individual isolates has major significance in further studies on the ecotoxicity of the AgNPs. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Plant growth-promoting activities for bacterial and fungal endophytes isolated from medicinal plant of Teucrium polium L.

    Directory of Open Access Journals (Sweden)

    Saad El-Din Hassan

    2017-11-01

    Full Text Available Bacterial and fungal endophytes are widespread inhabitants inside plant tissues and have been shown to assist plant growth and health. However, little is known about plant growth-promoting endophytes (PGPE of medicinal plants. Therefore, the aims of this study were to identify bacterial and fungal endophytes of Teucrium polium and to characterize plant growth-promoting (PGP properties of these endophytes. Seven bacterial endophytes were isolated and identified as Bacillus cereus and Bacillus subtilis, where five endophytic fungi were obtained and assigned to Penicillium chrysogenum and Penicillium crustosum. The isolated endophytes differentially produced indole acetic acid (IAA and ammonia, and in addition to their enzymatic and antimicrobial activities, they exhibited variable capacity for phosphate solubilization. In order to investigate the effect of endophytes on plant growth, four representative endophytes and their consortiums were selected concerning to their potential ability to promote plant growth. The results indicated that microbial endophytes isolated from medicinal plants possessing a vital role to improve plant growth and could be used as inoculants to establish a sustainable crop production system.

  16. Plant growth-promoting activities for bacterial and fungal endophytes isolated from medicinal plant of Teucrium polium L.

    Science.gov (United States)

    Hassan, Saad El-Din

    2017-11-01

    Bacterial and fungal endophytes are widespread inhabitants inside plant tissues and have been shown to assist plant growth and health. However, little is known about plant growth-promoting endophytes (PGPE) of medicinal plants. Therefore, the aims of this study were to identify bacterial and fungal endophytes of Teucrium polium and to characterize plant growth-promoting (PGP) properties of these endophytes. Seven bacterial endophytes were isolated and identified as Bacillus cereus and Bacillus subtilis , where five endophytic fungi were obtained and assigned to Penicillium chrysogenum and Penicillium crustosum . The isolated endophytes differentially produced indole acetic acid (IAA) and ammonia, and in addition to their enzymatic and antimicrobial activities, they exhibited variable capacity for phosphate solubilization. In order to investigate the effect of endophytes on plant growth, four representative endophytes and their consortiums were selected concerning to their potential ability to promote plant growth. The results indicated that microbial endophytes isolated from medicinal plants possessing a vital role to improve plant growth and could be used as inoculants to establish a sustainable crop production system.

  17. Biosynthesis of gold and silver nanoparticles using a novel marine strain of Stenotrophomonas.

    Science.gov (United States)

    Malhotra, Ankit; Dolma, Kunzes; Kaur, Navjot; Rathore, Y S; Ashish; Mayilraj, S; Choudhury, Anirban Roy

    2013-08-01

    The present study aims at exploiting marine microbial diversity for biosynthesis of metal nanoparticles and also investigates role of microbial proteins in the process of bio-mineralization of gold and silver. This is the first report for concurrent production of gold and silver nanoparticles (AuNPs and AgNPs) by extracellular secretion of a novel strain of Stenotrophomonas, isolated from Indian marine origin. This novel strain has faster rate kinetics for AgNPs synthesis than any other organism reported earlier. The nanoparticles were further characterized using UV-vis spectrophotometer, TEM, DLS and EDAX confirming their size ranging from 10-50 nm and 40-60 nm in dimensions for AuNPs and AgNPs, respectively. TEM analysis indicated formation of multi-shaped nanoparticles with heterogeneous size distribution in both the cases. Finally, the SDS-PAGE analysis of extracellular media supernatant suggested a potential involvement of certain low molecular weight secretory proteins in AuNPs and AgNPs biosynthesis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Ceftaroline activity against bacterial organisms isolated from acute bacterial skin and skin structure infections in United States medical centers (2009-2011).

    Science.gov (United States)

    Pfaller, Michael A; Flamm, Robert K; Sader, Helio S; Jones, Ronald N

    2014-04-01

    Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil, is a new cephalosporin with bactericidal activity against resistant Gram-positive organisms including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant strains of Streptococcus pneumoniae, and commonly isolated Gram-negative organisms, including ceftriaxone-susceptible Enterobacteriaceae. We evaluated the in vitro activity of ceftaroline and selected comparator agents against bacterial isolates collected from patients with acute bacterial skin and skin structure infections (ABSSSIs) in the USA. A total of 6222 isolates were collected from 67 medical centers distributed across all nine USA census regions between 2009 and 2011 and tested for susceptibility by reference broth microdilution methods. Ceftaroline was very active against S. aureus (MIC50/90, 0.5/1 μg/mL; 99.6% susceptible), including MRSA (MIC50/90, 0.5/1 μg/mL; 99.1% susceptible). Against β-hemolytic streptococci, the activity of ceftaroline (MIC50/90, ≤0.015/0.03 μg/mL; 100.0% susceptible) was comparable to that of both penicillin (MIC50/90, ≤0.06/≤0.06 μg/mL; 100.0% susceptible) and ceftriaxone (MIC50/90, ≤0.25/≤0.25 μg/mL; 100.0% susceptible). Ceftaroline was also highly active against viridans group streptococci (MIC50/90, 0.03/0.06 μg/mL). Similar to ceftriaxone and ceftazidime, ceftaroline was active against wild-type strains of Escherichia coli (MIC50/90, 0.12/0.25 μg/mL; 94.0% susceptible) and Klebsiella pneumoniae (MIC50/90, 0.12/0.25 μg/mL; 96.8% susceptible); however, the ceftaroline activity was compromised among strains with an extended-spectrum β-lactamase-phenotype (MIC50/90, >32/>32 μg/mL for both E. coli and K. pneumoniae). In summary, ceftaroline showed potent activity against a large contemporary collection (6222) of bacterial isolates associated with ABSSSI in the USA. © 2014.

  19. Isolation and identification of bacterial populations of zoonotic importance from captive non-venomous snakes in Malaysia.

    Science.gov (United States)

    Abba, Yusuf; Ilyasu, Yusuf Maina; Noordin, Mustapha Mohamed

    2017-07-01

    Captivity of non-venomous snakes such as python and boa are common in zoos, aquariums and as pets in households. Poor captivity conditions expose these reptiles to numerous pathogens which may result in disease conditions. The purpose of this study was to investigate the common bacteria isolated from necropsied captive snakes in Malaysia over a five year period. A total of 27 snake carcasses presented for necropsy at the Universiti Putra Malaysia (UPM) were used in this survey. Samples were aseptically obtained at necropsy from different organs/tissues (lung, liver, heart, kindey, oesophagus, lymph node, stomach, spinal cord, spleen, intestine) and cultured onto 5% blood and McConkey agar, respectively. Gram staining, morphological evaluation and biochemical test such as oxidase, catalase and coagulase were used to tentatively identify the presumptive bacterial isolates. Pythons had the highest number of cases (81.3%) followed by anaconda (14.8%) and boa (3.7%). Mixed infection accounted for 81.5% in all snakes and was highest in pythons (63%). However, single infection was only observed in pythons (18.5%). A total of 82.7%, 95.4% and 100% of the bacterial isolates from python, anaconda and boa, respectively were gram negative. Aeromonas spp was the most frequently isolated bacteria in pythons and anaconda with incidences of 25 (18%) and 8 (36.6%) with no difference (p > 0.05) in incidence, respectively, while Salmonella spp was the most frequently isolated in boa and significantly higher (p < 0.05) than in python and anaconda. Bacteria species were most frequently isolated from the kidney of pythons 35 (25.2%), intestines of anacondas 11 (50%) and stomach of boa 3 (30%). This study showed that captive pythons harbored more bacterial species than anaconda or boa. Most of the bacterial species isolated from these snakes have public health importance and have been incriminated in human infections worldwide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Antimicrobial susceptibility pattern of bacterial isolates from surgical wound infections in Tertiary Care Hospital in Allahabad, India

    Directory of Open Access Journals (Sweden)

    A K Kapoor

    2012-01-01

    Full Text Available The aim of present study to analyze the occurrence and in-vitro antimicrobial susceptibility of bacterial pathogens isolated from surgical wound infections. Specimens from a total of 129 patients undergoing either emergency or elective surgery were collected from infected sites or stitch lines and inoculated onto appropriate media. The bacterial cultures were identified utilizing standard microbiological and biochemical methods. Isolates were tested for susceptibility to antimicrobials using the Kirby Bauer disk diffusion method. Statistical analysis was performed using the chi-square test. Of 129 patients investigated (62 emergency and 67 elective surgery cases, bacterial isolates were isolated with almost equal frequency both from emergency and elective surgery cases. Of 108 (83.72% culture positive samples, 62 (57.41% were Gram negative, 39 (36.11% Gram positive, and 7 (6.48% showed multiple organisms. Of total 115 bacteria isolated (101 single and 7 double organisms culture positive, 33 (28.69% were Escherichia coli and were also the commonest; followed by Staphylococcus aureus, 30 (26.09% cases. S. aureus and Streptococcus spp. showed maximum susceptibility (100% to linezolid and vancomycin. Maximum susceptibility of E. coli was observed to ciprofloxacin (75.7%, followed by gentamicin (54.5%; of Klebsiella spp. to ceftriaxone and gentamicin (66.6% each, of Proteus spp. to gentamicin (70% followed by ciprofloxacin (60%, and of Pseudomonas aeruginosa to piperacillin (100% and tobramycin (71.4%. E. coli and S. aureus were the most common and Salmonella spp. and Acinetobacter spp. were the least common organism causing surgical site infections. The definitive therapy included ciprofloxacin and gentamicin for E. coli; linezolid and vancomycin for S. aureus and Streptococcus spp; ceftriaxone and ciprofloxacin for Klebsiella spp., Citrobacter spp., acinetobacter spp and Salmonella spp.

  1. The Unculturables: targeted isolation of bacterial species associated with canine periodontal health or disease from dental plaque.

    Science.gov (United States)

    Davis, Ian J; Bull, Christopher; Horsfall, Alexander; Morley, Ian; Harris, Stephen

    2014-08-01

    The current inability to culture the entirety of observed bacteria is well known and with the advent of ever more powerful molecular tools, that can survey bacterial communities at previously unattainable depth, the gap in our capacity to culture and define all of these species increases exponentially. This gap has essentially become the rate limiting step in determining how the knowledge of which species are present in a sample can be applied to understand the role of these species in an ecosystem or disease process. A case in point is periodontal disease, which is the most widespread oral disease in dogs. If untreated the disease results in significant pain, eventual loss of the dentition and potentially an increased risk of systemic diseases. Previous molecular based studies have identified the bacterial species associated with periodontal disease in dogs; however without cultured strains from many of these species it has not been possible to study whether they play a role in the disease process. Using a quantitative polymerase chain reaction (qPCR) directed approach a range of microbiological media were screened and optimized to enrich for previously uncultivated target species. A systematic screening methodology was then employed to isolate the species of interest. In cases where the target species were not cultivable in isolation, helper strains grown underneath a nitrocellulose membrane were used to provide the necessary growth factors. This guided media optimization approach enabled the purification of 14 species, 8 of which we had previously been unable to cultivate in isolation. It is also applicable to the targeted isolation of isolates from species that have previously been cultured (for example to study intra-species variation) as demonstrated by the successful isolation of 6 targeted isolates of already cultured species. To our knowledge this is the first time this combination of qPCR guided media optimization, strategic screening and helper strain

  2. Aspiration in head and neck cancer patients: a single centre experience of clinical profile, bacterial isolates and antibiotic sensitivity pattern.

    Science.gov (United States)

    Lakshmaiah, K C; Sirsath, Nagesh T; Subramanyam, Jayshree R; Govind, Babu K; Lokanatha, D; Shenoy, Ashok M

    2013-07-01

    Most patients with head and neck cancer have dysphagia and are at increased risk of having aspiration and subsequent pneumonia. It can cause prolonged hospitalization, treatment delay and/or interruption and mortality in cancer patients. The treatment of these infections often relies on empirical antibiotics based on local microbiology and antibiotic sensitivity patterns. The aim of present study is to analyse respiratory tract pathogens isolated by sputum culture in head and neck cancer patients undergoing treatment at a tertiary cancer centre in South India who presented with features of aspiration. The study is carried out to establish empirical antibiotic policy for head and neck cancer patients who present with features of aspiration. This was a retrospective study. The study included sputum samples sent for culture and sensitivity from January 2011 to December 2012. Analysis of microbiologic species isolated in sputum specimen and the antibiotic sensitivity pattern of the bacterial isolates was performed. A detailed study of case files of all patients was done to find out which is the most common site prone for producing aspiration. There were 47 (31.54 %) gram positive isolates and 102 (68.45 %) gram negative isolates. The most common bacterial isolates were Klebsiella pneumoniae (25.50 %), Pseudomonas aeruginosa (16.77 %) and Haemophilus influenzae (15.43 %). Levofloxacin was the most effective antibiotic with excellent activity against both gram positive and gram negative isolates. Most patients with aspiration had laryngeal cancer (34.89 %). Aspiration pneumonia was present in 14 (9.39 %) patients. Gram negative bacteria are common etiologic agents in head and neck cancer patients presenting with features of aspiration. Levofloxacin should be started as empirical antibiotic in these patients while awaiting sputum culture sensitivity report. As aspiration in head and neck cancer is an underreported event such institutional antibiotic sensitivity

  3. Antibiotic Resistance and Virulence Phenotypes of Recent Bacterial Strains Isolated from Urinary Tract Infections in Elderly Patients with Prostatic Disease.

    Science.gov (United States)

    Delcaru, Cristina; Podgoreanu, Paulina; Alexandru, Ionela; Popescu, Nela; Măruţescu, Luminiţa; Bleotu, Coralia; Mogoşanu, George Dan; Chifiriuc, Mariana Carmen; Gluck, Marinela; Lazăr, Veronica

    2017-05-31

    Acute bacterial prostatitis is one of the frequent complications of urinary tract infection (UTI). From the approximately 10% of men having prostatitis, 7% experience a bacterial prostatitis. The purpose of this study was to investigate the prevalence of uropathogens associated with UTIs in older patients with benign prostatic hyperplasia and to assess their susceptibility to commonly prescribed antibiotics as well as the relationships between microbial virulence and resistance features. Uropathogenic Escherichia coli was found to be the most frequent bacterial strain isolated from patients with benign prostatic hyperplasia, followed by Enterococcus spp., Enterobacter spp., Klebsiella spp., Proteus spp., Pseudomonas aeruginosa , and Serratia marcescens . Increased resistance rates to tetracyclines, quinolones, and sulfonamides were registered. Besides their resistance profiles, the uropathogenic isolates produced various virulence factors with possible implications in the pathogenesis process. The great majority of the uropathogenic isolates revealed a high capacity to adhere to HEp-2 cell monolayer in vitro, mostly exhibiting a localized adherence pattern. Differences in the repertoire of soluble virulence factors that can affect bacterial growth and persistence within the urinary tract were detected. The Gram-negative strains produced pore-forming toxins-such as hemolysins, lecithinases, and lipases-proteases, siderophore-like molecules resulted from the esculin hydrolysis and amylases, while Enterococcus sp. strains were positive only for caseinase and esculin hydrolase. Our study demonstrates that necessity of investigating the etiology and local resistance patterns of uropathogenic organisms, which is crucial for determining appropriate empirical antibiotic treatment in elderly patients with UTI, while establishing correlations between resistance and virulence profiles could provide valuable input about the clinical evolution and recurrence rates of UTI.

  4. Antibiotic Resistance and Virulence Phenotypes of Recent Bacterial Strains Isolated from Urinary Tract Infections in Elderly Patients with Prostatic Disease

    Directory of Open Access Journals (Sweden)

    Cristina Delcaru

    2017-05-01

    Full Text Available Acute bacterial prostatitis is one of the frequent complications of urinary tract infection (UTI. From the approximately 10% of men having prostatitis, 7% experience a bacterial prostatitis. The purpose of this study was to investigate the prevalence of uropathogens associated with UTIs in older patients with benign prostatic hyperplasia and to assess their susceptibility to commonly prescribed antibiotics as well as the relationships between microbial virulence and resistance features. Uropathogenic Escherichia coli was found to be the most frequent bacterial strain isolated from patients with benign prostatic hyperplasia, followed by Enterococcus spp., Enterobacter spp., Klebsiella spp., Proteus spp., Pseudomonas aeruginosa, and Serratia marcescens. Increased resistance rates to tetracyclines, quinolones, and sulfonamides were registered. Besides their resistance profiles, the uropathogenic isolates produced various virulence factors with possible implications in the pathogenesis process. The great majority of the uropathogenic isolates revealed a high capacity to adhere to HEp-2 cell monolayer in vitro, mostly exhibiting a localized adherence pattern. Differences in the repertoire of soluble virulence factors that can affect bacterial growth and persistence within the urinary tract were detected. The Gram-negative strains produced pore-forming toxins—such as hemolysins, lecithinases, and lipases—proteases, siderophore-like molecules resulted from the esculin hydrolysis and amylases, while Enterococcus sp. strains were positive only for caseinase and esculin hydrolase. Our study demonstrates that necessity of investigating the etiology and local resistance patterns of uropathogenic organisms, which is crucial for determining appropriate empirical antibiotic treatment in elderly patients with UTI, while establishing correlations between resistance and virulence profiles could provide valuable input about the clinical evolution and

  5. First Isolation and Molecular Characterization of Bacteriophages Infecting Acidovorax citrulli, the Causal Agent of Bacterial Fruit Blotch

    Directory of Open Access Journals (Sweden)

    Aryan Rahimi-Midani

    2018-02-01

    Full Text Available Bacteriophages of Acidovorax citrulli, the causal agent of bacterial fruit blotch, were isolated from 39 watermelon, pumpkin, and cucumber leaf samples collected from various regions of Korea and tested against 18 A. citrulli strains. Among the six phages isolated, ACP17 forms the largest plaque, and exhibits the morphology of phages in the Myoviridae family with a head diameter of 100 ± 5 nm and tail length of 150 ± 5 nm. ACP17 has eclipse and latent periods of 25 ± 5 min and 50 ± 5 min, respectively, and a burst size of 120. The genome of ACP17 is 156,281 base pairs with a G + C content of 58.7%, 263 open reading frames, and 4 transfer RNA genes. Blast search and phylogenetic analysis of the major capsid protein showed that ACP17 has limited homology to two Stentrophomonas phages, suggesting that ACP17 is a new type of Myoviridae isolated from A. citrulli.

  6. Poly-β-hydroxybutyrate and exopolysaccharide biosynthesis by bacterial isolates from pigeonpea [Cajanus cajan (L.) Millsp] root nodules.

    Science.gov (United States)

    Fernandes, Paulo Ivan; de Oliveira, Paulo Jansen; Rumjanek, Norma Gouvêa; Xavier, Gustavo Ribeiro

    2011-02-01

    The bacterial strains that are able to produce biopolymers that are applied in industrial sectors present a source of renewable resources. Some microorganisms are already applied at several industrial sectors, but the prospecting of new microbes must bring microorganisms that are feasible to produce interesting biopolymers more efficiently and in cheaper conditions. Among the biopolymers applied industrially, polyhydroxybutyrate (PHB) and exopolysaccharides (EPS) stand out because of its applications, mainly in biodegradable plastic production and in food industry, respectively. In this context, the capacity of bacteria isolated from pigeonpea root nodules to produce EPS and PHB was evaluated, as well as the cultural characterization of these isolates. Among the 38 isolates evaluated, the majority presented fast growth and ability to acidify the culture media. Regarding the biopolymer production, five isolates produced more than 10 mg PHB per liter of culture medium. Six EPS producing bacteria achieved more than 200 mg EPS per liter of culture medium. Evaluating different carbon sources, the PHB productivity of the isolate 24.6b reached 69% of cell dry weight when cultured with starch as sole carbon source, and the isolate 8.1c synthesized 53% PHB in dry cell biomass and more than 1.3 g L⁻¹ of EPS when grown using xylose as sole carbon source.

  7. l-Glucitol Catabolism in Stenotrophomonas maltophilia Ac

    Science.gov (United States)

    Brechtel, Elke; Huwig, Alexander; Giffhorn, Friedrich

    2002-01-01

    The carbohydrate catabolism of the bacterium Stenotrophomonas maltophilia Ac (previously named Pseudomonas sp. strain Ac), which is known to convert the unnatural polyol l-glucitol to d-sorbose during growth on the former as the sole source of carbon and energy, was studied in detail. All enzymes operating in a pathway that channels l-glucitol via d-sorbose into compounds of the intermediary metabolism were demonstrated, and for some prominent reactions the products of conversion were identified. d-Sorbose was converted by C-3 epimerization to d-tagatose, which, in turn, was isomerized to d-galactose. d-Galactose was the initial substrate of the De Ley-Doudoroff pathway, involving reactions of NAD-dependent oxidation of d-galactose to d-galactonate, its dehydration to 2-keto-3-deoxy-d-galactonate, and its phosphorylation to 2-keto-3-deoxy-d-galactonate 6-phosphate. Finally, aldol cleavage yielded pyruvate and d-glycerate 3-phosphate as the central metabolic intermediates. PMID:11823194

  8. Analysis of raw meat for heavy metals and bacterial contamination and comparison of antibiotic susceptibility of isolated bacteria

    International Nuclear Information System (INIS)

    Ahmad, F.

    2016-01-01

    The focus of the study was to analyze the commercially available meat for its heavy metal contents and bacterial contamination. The meat samples were collected from four commercial markets of Lahore, i.e., as Wafaqi Colony (Site I),Township (Site II), G-1 Market (Site III) and Zenith (Site IV), and analyzed for heavy metal [i.e., manganese (Mn), nickel (Ni), chromium (Cr), cadmium (Cd) and copper (Cu)] contents and bacterial contaminants (E. coli, Pseudomonas sp., Bacillus sp. and Salmonella sp.) Atomic absorption spectrophotometery was employed for the detection of the heavy metals and plate count method was used for the detection of bacterial contaminants. The Ni concentration in the Site II sample only and Cd concentration in all meat samples were found above the standard value and the concentration of other metals (Cu, Cr, and Mn) was less than the standard concentrations. Bacterial (E. coli, Pseudomonas sp., Bacillus sp., Salmonella sp. and Staphylococcus sp.) contamination was found in all meat samples; however, the number was a little lower in the Site IV samples. Statistical analysis was done, by one-way ANOVA using SPSS, to compare heavy metal contamination in the meat samples. The results showed distribution of heavy metals in all meat samples there was significant difference of Ni concentration in the meat samples. The measure of antibiotic susceptibility showed that isolated species of bacteria were resistant to lincomycin, streptomycin, tertracyclin, ampicillin, amoxicillin and doxycyclin, but did not survive in the medium containing ofloxacin. (author)

  9. Isolation and characterization of diuron-degrading bacteria from lotic surface water.

    Science.gov (United States)

    Batisson, Isabelle; Pesce, Stéphane; Besse-Hoggan, Pascale; Sancelme, Martine; Bohatier, Jacques

    2007-11-01

    The bacterial community structure of a diuron-degrading enrichment culture from lotic surface water samples was analyzed and the diuron-degrading strains were selected using a series of techniques combining temporal temperature gradient gel electrophoresis (TTGE) of 16 S rDNA gene V1-V3 variable regions, isolation of strains on agar plates, colony hybridization methods, and biodegradation assays. The TTGE fingerprints revealed that diuron had a strong impact on bacterial community structure and highlighted both diuron-sensitive and diuron-adapted bacterial strains. Two bacterial strains, designated IB78 and IB93 and identified as belonging to Pseudomonas sp. and Stenotrophomonas sp., were isolated and shown to degrade diuron in pure resting cells in a first-order kinetic reaction during the first 24 h of incubation with no 3,4-DCA detected. The percentages of degradation varied from 25% to 60% for IB78 and 20% to 65% for IB93 and for a diuron concentration range from 20 mg/L to 2 mg/L, respectively. It is interesting to note that diuron was less degraded by single isolates than by mixed resting cells, thereby underlining a cumulative effect between these two strains. To the best of our knowledge, this is the first report of diuron-degrading strains isolated from lotic surface water.

  10. Evaluation of a Stenotrophomonas maltophilia bacteremia cluster in hematopoietic stem cell transplantation recipients using whole genome sequencing

    Directory of Open Access Journals (Sweden)

    Stefanie Kampmeier

    2017-11-01

    Full Text Available Abstract Background Stenotrophomonas maltophilia ubiquitously occurs in the hospital environment. This opportunistic pathogen can cause severe infections in immunocompromised hosts such as hematopoietic stem cell transplantation (HSCT recipients. Between February and July 2016, a cluster of four patients on the HSCT unit suffered from S. maltophilia bloodstream infections (BSI. Methods For epidemiological investigation we retrospectively identified the colonization status of patients admitted to the ward during this time period and performed environmental monitoring of shower heads, shower outlets, washbasins and toilets in patient rooms. We tested antibiotic susceptibility of detected S. maltophilia isolates. Environmental and blood culture samples were subjected to whole genome sequence (WGS-based typing. Results Of four patients with S. maltophlilia BSI, three were found to be colonized previously. In addition, retrospective investigations revealed two patients being colonized in anal swab samples but not infected. Environmental monitoring revealed one shower outlet contaminated with S. maltophilia. Antibiotic susceptibility testing of seven S. maltophlia strains resulted in two trimethoprim/sulfamethoxazole resistant and five susceptible isolates, however, not excluding an outbreak scenario. WGS-based typing did not result in any close genotypic relationship among the patients’ isolates. In contrast, one environmental isolate from a shower outlet was closely related to a single patient’s isolate. Conclusion WGS-based typing successfully refuted an outbreak of S. maltophilia on a HSCT ward but uncoverd that sanitary installations can be an actual source of S. maltophilia transmissions.

  11. Final Scientific Report: Bacterial Nanowires and Extracellular Electron Transfer to Heavy Metals and Radionuclides by Bacterial Isolates from DOE Field Research Centers

    Energy Technology Data Exchange (ETDEWEB)

    Nealson, Kenneth [Univ. of Southern California, Los Angeles, CA (United States)

    2016-12-20

    This proposal involved the study of bacteria capable of transferring electrons from the bacterial cells to electron acceptors located outside the cell. These could be either insoluble minerals that were transformed into soluble products upon the addition of electrons, or they could be soluble salts like uranium or chromium, that become insoluble upon the addition of electrons. This process is called extracellular electron transport or EET, and can be done directly by cellular contact, or via conductive appendages called bacterial nanowires. In this work we examined a number of different bacteria for their ability to perform EET, and also looked at their ability to produce conductive nanowires that can be used for EET at a distance away from the EET-capable cells. In the work, new bacteria were isolated, new abilities of EET were examined, and many new methods were developed, and carefully described in the literature. These studies set the stage for future work dealing with the bioremediation of toxic metals like uranium and chromium. They also point out that EET (and conductive nanowires) are far more common that had been appreciated, and may be involved with energy transfer not only in sediments, but in symbioses between different bacteria, and in symbiosis/pathogenesis between bacteria and higher organisms.

  12. Final Scientific Report: Bacterial Nanowires and Extracellular Electron Transfer to Heavy Metals and Radionuclides by Bacterial Isolates from DOE Field Research Centers

    International Nuclear Information System (INIS)

    Nealson, Kenneth

    2016-01-01

    This proposal involved the study of bacteria capable of transferring electrons from the bacterial cells to electron acceptors located outside the cell. These could be either insoluble minerals that were transformed into soluble products upon the addition of electrons, or they could be soluble salts like uranium or chromium, that become insoluble upon the addition of electrons. This process is called extracellular electron transport or EET, and can be done directly by cellular contact, or via conductive appendages called bacterial nanowires. In this work we examined a number of different bacteria for their ability to perform EET, and also looked at their ability to produce conductive nanowires that can be used for EET at a distance away from the EET-capable cells. In the work, new bacteria were isolated, new abilities of EET were examined, and many new methods were developed, and carefully described in the literature. These studies set the stage for future work dealing with the bioremediation of toxic metals like uranium and chromium. They also point out that EET (and conductive nanowires) are far more common that had been appreciated, and may be involved with energy transfer not only in sediments, but in symbioses between different bacteria, and in symbiosis/pathogenesis between bacteria and higher organisms.

  13. Comparative Genomics of Environmental and Clinical Stenotrophomonas maltophilia Strains with Different Antibiotic Resistance Profiles.

    Science.gov (United States)

    Youenou, Benjamin; Favre-Bonté, Sabine; Bodilis, Josselin; Brothier, Elisabeth; Dubost, Audrey; Muller, Daniel; Nazaret, Sylvie

    2015-08-14

    Stenotrophomonas maltophilia, a ubiquitous Gram-negative γ-proteobacterium, has emerged as an important opportunistic pathogen responsible for nosocomial infections. A major characteristic of clinical isolates is their high intrinsic or acquired antibiotic resistance level. The aim of this study was to decipher the genetic determinism of antibiotic resistance among strains from different origins (i.e., natural environment and clinical origin) showing various antibiotic resistance profiles. To this purpose, we selected three strains isolated from soil collected in France or Burkina Faso that showed contrasting antibiotic resistance profiles. After whole-genome sequencing, the phylogenetic relationships of these 3 strains and 11 strains with available genome sequences were determined. Results showed that a strain's phylogeny did not match their origin or antibiotic resistance profiles. Numerous antibiotic resistance coding genes and efflux pump operons were revealed by the genome analysis, with 57% of the identified genes not previously described. No major variation in the antibiotic resistance gene content was observed between strains irrespective of their origin and antibiotic resistance profiles. Although environmental strains generally carry as many multidrug resistant (MDR) efflux pumps as clinical strains, the absence of resistance-nodulation-division (RND) pumps (i.e., SmeABC) previously described to be specific to S. maltophilia was revealed in two environmental strains (BurA1 and PierC1). Furthermore the genome analysis of the environmental MDR strain BurA1 showed the absence of SmeABC but the presence of another putative MDR RND efflux pump, named EbyCAB on a genomic island probably acquired through horizontal gene transfer. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. Biodegradation of anthracene by a newly isolated bacterial strain, Bacillus thuringiensis AT.ISM.1, isolated from a fly ash deposition site.

    Science.gov (United States)

    Tarafdar, A; Sinha, A; Masto, R E

    2017-10-01

    The current study is aimed to evaluate the mechanism of anthracene degradation by a bacterial strain isolated from fly ash deposition site near Jamadoba Coal Preparation Plant, Jharkhand, India. The Bushnell-Haas media cultured (containing anthracene as sole carbon source) bacterial isolate was identified by 16S rRNA gene sequence coding as the Bacillus thuringiensis strain, which showed the efficiency to degrade anthracene. The degradation efficiency of the strain has been estimated to be around 91% (for 40 mg l -1 of anthracene concentration) after 2 weeks of incubation at 33-36°C and initial pH of 6·8-7. The growth kinetics of the isolated strain has been described well by the Haldane-Andrews model of microbial growth pattern for inhibitory substrate, with a correlation factor (R 2 value) of 0·9790. The maximum specific growth rate (μ max ) was 0·01053 h -1 and the value of inhibition coefficient for Haldane model was specified as 18·2448 mg l -1 . In the present study, some diphenol metabolites were identified besides the known possible biodegradation products. Polycyclic aromatic hydrocarbons (PAHs) are recognized as significant health risks and consequently listed as priority pollutants by environmental protection agencies across the globe. The aim of the present study was to degrade one of the important PAHs, anthracene, by a newly isolated Bacillus thuringiensis strain. This is the first report of anthracene degradation by B. thuringiensis. This is also the very first growth kinetic study of a bacteria in an anthracene-containing medium. Some diphenol metabolites were found for the first time as anthracene biodegradation by-products, which can be an indication towards a new pathway. © 2017 The Society for Applied Microbiology.

  15. Common bacterial isolates, clinical outcome and TB meningitis in children admitted at Morogoro Regional Referral Hospital, Tanzania

    Directory of Open Access Journals (Sweden)

    Ramadhani Salum Chambuso

    2017-01-01

    Full Text Available Background: Bacterial meningitis is still one of the major causes of deaths, disabilities, and mental retardation in children in Morogoro region. To study the current meningitis burden, we evaluated the common bacterial isolates and clinical outcome of the disease in the region. Methods: We conducted a hospital-based prospective study on 1352 children aged between 7 days and 12 years admitted in pediatric wards at Morogoro Regional Referral Hospital for 7 months. Cerebrospinal fluid (CSF for laboratory microbiological examination was collected by lumbar puncture in 72 children with signs and symptoms of meningitis. Latex agglutination test was used to confirm the bacterial colonies in the culture. Chi-square test was used for relative risk with 95% confidence intervals; statistical analysis and tests were considered statistically significant when P < 0.05. Results: Among 72 CSF samples, 23 (31.9% were positive for Streptococcus pneumoniae, 6 (8.3% for Haemophilus influenzae, 5 (6.9% for Group B Streptococcus, 3 (4.2% for Escherichia coli, and 1 (1.4% was positive for Mycobacterium tuberculosis. Furthermore, 34 CSF samples showed no bacteria growth in the culture media. In addition, 39 children (54.2% did not respond to the treatment, whereas 79.5% (n = 39 of them died, while 20.5% (n = 39 of them were referred to a tertiary hospital. Nevertheless, the incidence of meningitis infection was 5.3% (n = 1352 among the admitted children. Conclusions: S. pneumoniae was the major laboratory-confirmed bacterial isolate associated with meningitis in children. We report for the first time the presence of tuberculous meningitis in Morogoro region. Ziehl–Neelsen staining for acid-fast bacilli should be mandatory for any case clinically suspected for meningitis.

  16. Common bacterial isolates, clinical outcome and TB meningitis in children admitted at Morogoro Regional Referral Hospital, Tanzania.

    Science.gov (United States)

    Chambuso, Ramadhani Salum; Mkhoi, Mkhoi Lord; Kaambo, Evelyn

    2017-01-01

    Bacterial meningitis is still one of the major causes of deaths, disabilities, and mental retardation in children in Morogoro region. To study the current meningitis burden, we evaluated the common bacterial isolates and clinical outcome of the disease in the region. We conducted a hospital-based prospective study on 1352 children aged between 7 days and 12 years admitted in pediatric wards at Morogoro Regional Referral Hospital for 7 months. Cerebrospinal fluid (CSF) for laboratory microbiological examination was collected by lumbar puncture in 72 children with signs and symptoms of meningitis. Latex agglutination test was used to confirm the bacterial colonies in the culture. Chi-square test was used for relative risk with 95% confidence intervals; statistical analysis and tests were considered statistically significant when P < 0.05. Among 72 CSF samples, 23 (31.9%) were positive for Streptococcus pneumoniae, 6 (8.3%) for Haemophilus influenzae, 5 (6.9%) for Group B Streptococcus, 3 (4.2%) for Escherichia coli, and 1 (1.4%) was positive for Mycobacterium tuberculosis. Furthermore, 34 CSF samples showed no bacteria growth in the culture media. In addition, 39 children (54.2%) did not respond to the treatment, whereas 79.5% (n = 39) of them died, while 20.5% (n = 39) of them were referred to a tertiary hospital. Nevertheless, the incidence of meningitis infection was 5.3% (n = 1352) among the admitted children. S. pneumoniae was the major laboratory-confirmed bacterial isolate associated with meningitis in children. We report for the first time the presence of tuberculous meningitis in Morogoro region. Ziehl-Neelsen staining for acid-fast bacilli should be mandatory for any case clinically suspected for meningitis.

  17. Pre-adapting parasitic phages to a pathogen leads to increased pathogen clearance and lowered resistance evolution with Pseudomonas aeruginosacystic fibrosis bacterial isolates

    DEFF Research Database (Denmark)

    Friman, Ville-Petri; Soanes-Brown, Daniel; Sierocinski, Pawel

    2016-01-01

    and then compared the efficacy of pre-adapted and non-adapted phages against ancestral bacterial strains. We found that evolved phages were more efficient in reducing bacterial densities than ancestral phages. This was primarily because only 50% of bacterial strains were able to evolve resistance to evolved phages......, while all bacteria were able to evolve some level of resistance to ancestral phages. While the rate of resistance evolution did not differ between intermittent and chronic isolates, it incurred a relatively higher growth cost for chronic isolates when measured in the absence of phages. This is likely...

  18. Prevalence of antimicrobial resistance among bacterial pathogens isolated from cattle in different European countries: 2002–2004

    Directory of Open Access Journals (Sweden)

    Stärk Katharina

    2008-07-01

    Full Text Available Abstract Background The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II was funded by the European Union (FAIR5-QLK2-2002-01146 for the period 2003–2005, with the aim to establish a continuous monitoring of antimicrobial susceptibility among veterinary laboratories in European countries based on validated and harmonised methodologies. Available summary data of the susceptibility testing of the bacterial pathogens from the different laboratories were collected. Method Antimicrobial susceptibility data for several bovine pathogens were obtained over a three year period (2002–2004. Each year the participating laboratories were requested to fill in excel-file templates with national summary data on the occurrence of antimicrobial resistance from different bacterial species. A proficiency test (EQAS – external quality assurance system for antimicrobial susceptibility testing was conducted each year to test the accuracy of antimicrobial susceptibility testing in the participating laboratories. The data from this testing demonstrated that for the species included in the EQAS the results are comparable between countries. Results Data from 25,241 isolates were collected from 13 European countries. For Staphylococcus aureus from bovine mastitis major differences were apparent in the occurrence of resistance between countries and between the different antimicrobial agents tested. The highest frequency of resistance was observed for penicillin. For Mannheimia haemolytica resistance to ampicillin, tetracycline and trimethoprim/sulphonamide were observed in France, the Netherlands and Portugal. All isolates of Pasteurella multocida isolated in Finland and most of those from Denmark, England (and Wales, Italy and Sweden were susceptible to the majority of the antimicrobials. Streptococcus dysgalactiae and Streptococcus uberis isolates from Sweden were fully susceptible. For the other countries some resistance was observed to

  19. Decreased Phototoxic Effects of TiO₂ Nanoparticles in Consortium of Bacterial Isolates from Domestic Waste Water.

    Directory of Open Access Journals (Sweden)

    Ankita Mathur

    Full Text Available This study is aimed to explore the toxicity of TiO2 nanoparticles at low concentrations (0.25, 0.50 & 1.00 μg/ml; on five bacterial isolates and their consortium in waste water medium both in dark and UVA conditions. To critically examine the toxic effects of nanoparticles and the response mechanism(s offered by microbes, several aspects were monitored viz. cell viability, ROS generation, SOD activity, membrane permeability, EPS release and biofilm formation. A dose and time dependent loss in viability was observed for treated isolates and the consortium. At the highest dose, after 24h, oxidative stress was examined which conclusively showed more ROS generation & cell permeability and less SOD activity in single isolates as compared to the consortium. As a defense mechanism, EPS release was enhanced in case of the consortium against the single isolates, and was observed to be dose dependent. Similar results were noticed for biofilm formation, which substantially increased at highest dose of nanoparticle exposure. Concluding, the consortium showed more resistance against the toxic effects of the TiO2 nanoparticles compared to the individual isolates.

  20. Evaluation of a Single Procedure Allowing the Isolation of Enteropathogenic Yersinia along with Other Bacterial Enteropathogens from Human Stools

    Science.gov (United States)

    Savin, Cyril; Leclercq, Alexandre; Carniel, Elisabeth

    2012-01-01

    Enteropathogenic Yersinia are among the most frequent agents of human diarrhea in temperate and cold countries. However, the incidence of yersiniosis is largely underestimated because of the peculiar growth characteristics of pathogenic Yersinia, which make their isolation from poly-contaminated samples difficult. The use of specific procedures for Yersinia isolation is required, but is expensive and time consuming, and therefore is not systematically performed in clinical pathology laboratories. A means to circumvent this problem would be to use a single procedure for the isolation of all bacterial enteropathogens. Since the Statens Serum Institut enteric medium (SSI) has been reported to allow the growth at 37°C of most Gram-negative bacteria, including Yersinia, our study aimed at evaluating its performances for Yersinia isolation, as compared to the commonly used Yersinia-specific semi-selective Cefsulodin-Irgasan-Novobiocin medium (CIN) incubated at 28°C. Our results show that Yersinia pseudotuberculosis growth was strongly inhibited on SSI at 37°C, and therefore that this medium is not suitable for the isolation of this species. All Yersinia enterocolitica strains tested grew on SSI, while some non-pathogenic Yersinia species were inhibited. The morphology of Y. enterocolitica colonies on SSI allowed their differentiation from various other Gram-negative bacteria commonly isolated from stool samples. However, in artificially contaminated human stools, the recovery of Y. enterocolitica colonies on SSI at 37°C was difficult and was 3 logs less sensitive than on CIN at 28°C. Therefore, despite its limitations, the use of a specific procedure (CIN incubated at 28°C) is still required for an efficient isolation of enteropathogenic Yersinia from stools. PMID:22911756

  1. Diversity and biosynthetic potential of culturable aerobic heterotrophic bacteria isolated from Magura Cave, Bulgaria

    Directory of Open Access Journals (Sweden)

    Tomova Iva

    2013-01-01

    Full Text Available Biocapacity of bacteria inhabiting karstic caves to produce valuable biologically active compounds is still slightly investigated. A total of 46 culturable heterotrophic bacteria were isolated under aerobic conditions from the Gallery with pre-historical drawings in Magura Cave, Bulgaria. Phylogenetic analysis revealed that most of bacterial isolates aff iliated with Proteobacteria (63%, followed by Actinobacteria (10.9%, Bacteroidetes (10.9%, and Firmicutes (6.5%. A strong domination of Gram-negative bacteria (total 81% belonging to nine genera: Serratia, Pseudomonas, Enterobacter, Sphingobacterium, Stenotrophomonas, Commamonas, Acinetobacter, Obesumbacterium, and Myroides, was observed. Gram-positive isolates were represented by the genera Bacillus, Arthrobacter, and Micrococcus. One isolate showed a signif icant phylogenetic distance to the closest neighbor and could represent а novel species. Heterotrophic bacterial isolates from Magura Cave were investigated for hydrolytic enzymes production, antimicrobial and hemolytic activity. Predominance of producers of protease (87%, followed by xanthan lyase (64%, lipase (40%, β-glycosidase (40%, and phytase (21% was observed. Over 75% of the isolates demonstrated antimicrobial and hemolytic activity. The results suggest that heterotrophic bacteria isolated from Magura Cave could be a valuable source of industrially relevant psychrotolerant enzymes and bioactive metabolites. This study is a f irst report on the taxonomic composition and biological activity of culturable bacteria inhabiting a cave in Bulgaria.

  2. Christensenella timonensis, a new bacterial species isolated from the human gut

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    S. Ndongo

    2016-09-01

    Full Text Available We propose a new species, Christensenella timonensis, strain Marseille-P2437T (CSUR P2437T, which was isolated from gut microbiota of a 66-year-old patient as a part of culturomics study. C. timonensis represents the second species isolated within the Christensenella genus.

  3. Larvicidal Activities of Indigenous Bacillus thuringiensis Isolates and Nematode Symbiotic Bacterial Toxins against the Mosquito Vector, Culex pipiens (Diptera: Culicidae

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    Ashraf M Ahmed

    2017-06-01

    Full Text Available Background: The incidence of mosquito-borne diseases and the resistance of mosquitoes to conventional pesticides have recently caused a panic to the authorities in the endemic countries. This study was conducted to identify native larvicidal biopesticides against Culex pipiens for utilization in the battle against mosquito-borne diseases.Methods: Larvicidal activities of new indigenous Bacillus thuringiensis isolates and crude toxin complexes (TCs of two nematode bacterial-symbionts, Photorhabdus luminescens akhurstii (HRM1 and Ph. luminescens akhurstii (HS1 that tested against Cx. pipiens. B. thuringiensis isolates were recovered from different environmental samples in Saudi Arabia, and the entomopathogenic nematodes, Heterorhabditis indica (HRM1 and He. sp (HS1 were iso­lated from Egypt. Larvicidal activities (LC50 and LC95 of the potentially active B. thuringiensis strains or TCs were then evaluated at 24 and 48h post-treatment.Results: Three B. thuringiensis isolates were almost as active as the reference B. thuringiensis israelensis (Bti-H14, and seven isolates were 1.6–5.4 times more toxic than Bti-H14. On the other hand, the TCs of the bacterial sym­bionts, HRM1 and HS1, showed promising larvicidal activities. HS1 showed LC50 of 2.54 folds that of HRM1 at 24h post-treatment. Moreover, histopathological examinations of the HS1-treated larvae showed deformations in midgut epithelial cells at 24h post-treatment.Conclusion: Synergistic activity and molecular characterization of these potentially active biocontrol agents are currently being investigated. These results may lead to the identification of eco-friend mosquito larvicidal product(s that could contribute to the battle against mosquito-borne diseases.

  4. Antimicrobial drug resistance among clinically relevant bacterial isolates in sub-Saharan Africa: a systematic review

    NARCIS (Netherlands)

    Leopold, Stije J.; van Leth, Frank; Tarekegn, Hayalnesh; Schultsz, Constance

    2014-01-01

    Little is known about the prevalence of antimicrobial resistance (AMR) amongst bacterial pathogens in sub-Saharan Africa (sSA), despite calls for continent-wide surveillance to inform empirical treatment guidelines. We searched PubMed and additional databases for susceptibility data of key pathogens

  5. Isolation and identification of bacterial glum blotch and leaf blight on ...

    African Journals Online (AJOL)

    . atrofaciens and P. syringae pv. syringae respectively are the bacterial diseases of wheat in Iran. The disease causes damage on wheat which leads to lots of yield and crop losses in the host plants. During the spring and summer of ...

  6. Occurrence of bacterial endosymbionts in Acanthamoeba spp. isolated from corneal and environmental specimens and contact lenses.

    Science.gov (United States)

    Fritsche, T R; Gautom, R K; Seyedirashti, S; Bergeron, D L; Lindquist, T D

    1993-01-01

    Free-living and parasitic protozoa are known to harbor a variety of endosymbiotic bacteria, although the roles such endosymbionts play in host survival, infectivity, and invasiveness are unclear. We have identified the presence of intracellular bacteria in 14 of 57 (24%) axenically grown Acanthamoeba isolates examined. These organisms are gram negative and non-acid fast, and they cannot be cultured by routine methodologies, although electron microscopy reveals evidence for multiplication within the amoebic cytoplasm. Examination for Legionella spp. with culture and nucleic acid probes has proven unsuccessful. We conclude that these bacteria are endosymbionts which have an obligate need to multiply within their amoebic hosts. Rod-shaped bacteria were identified in 5 of 23 clinical Acanthamoeba isolates (3 of 19 corneal isolates and 2 of 4 contact lens isolates), 4 of 25 environmental Acanthamoeba isolates, and 2 of 9 American Type Culture Collection Acanthamoeba isolates (ATCC 30868 and ATCC 30871) previously unrecognized as having endosymbionts. Coccus-shaped bacteria were present in one clinical (corneal) isolate and two environmental isolates. There was no statistical difference (P > 0.8) between the numbers of endosymbiont strains originating from clinical (26% positive) and environmental (24% positive) amoebic isolates, suggesting that the presence alone of these bacteria does not enhance amoebic infectivity. Rods and cocci were found in both clinical and environmental isolates from different geographical areas (Seattle, Wash., and Portland, Oreg.), demonstrating their widespread occurrence in nature. Our findings suggest that endosymbiosis occurs commonly among members of the family Acanthamoebidae and that the endosymbionts comprise a diverse taxonomic assemblage. The role such endosymbionts may play in pathogenesis remains unknown, although a variety of exogenous bacteria have been implicated in the development of amoebic keratitis, warranting further

  7. Comparison of clinical signs and bacterial isolates of postpartum endometritis in holstein dairy cows in Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Rahim Ahmadi

    2017-12-01

    Full Text Available The aim of this study was to determine the uterine bacteria in cows with endometritis and to compare other characteristics in cases of endometritis without bacterial growth, with Trueperella pyogenes (Arcanobacterium pyogenes or other bacteria. In total, 86 Holstein cows with postpartum endometritis from 13 commercial dairy herds were sampled once between 21-35 days postpartum. We used several diagnostic techniques for endometritis such as external observation, vaginal exam, rectal palpation, ultrasonography, and cervical and uterine cytological examination. Clear mucus with flakes of pus (E1, mucopurulent discharge (E2, and purulent discharge (E3 are three groups of endometritis. A transcervical double-guarded swab was used for bacterial sampling. The samples were cultured aerobic and anaerobically and biochemical tests were used for differentiation. Measurements were compared between groups: A, no growth (n=47; B, positive bacterial growth without T. pyogenes (n=21; and C, positive bacterial growth with T. pyogenes (n=18. There were no differences (P>0.05 in uterine wall thickness, body condition score (BCS and milk yield between the groups. The uterine horn diameter was largest in groups A (4.30±0.88 in comparison with groups B (4.81±1.17 and C (5.53±2.17 (P<0.05. The percentage of neutrophiles in smears of the uterine discharge (45.7±33.4 in group C was higher (P<0.05 than in groups A (14.5±22.7 and B (23.5±24.0. Eighty-three percent of group C have shown purulent discharge. In conclusion, the facultative anaerobe T. pyogenes may be the most common bacterial agent of postpartum endometritis in Holstein dairy cows in Iran.

  8. Are animals a source of Stenotrophomonas maltophilia in human infections? Contributions of a nationwide molecular study.

    Science.gov (United States)

    Jayol, Aurélie; Corlouer, Camille; Haenni, Marisa; Darty, Mélanie; Maillard, Karine; Desroches, Marine; Lamy, Brigitte; Jumas-Bilak, Estelle; Madec, Jean-Yves; Decousser, Jean-Winoc

    2018-02-27

    Stenotrophomonas maltophilia (Sm) is an archetypal environmental opportunistic bacterium responsible for health care-associated infections. The role of animals in human Sm infections is unknown. This study aims to reveal the genetic and phylogenetic relationships between pathogenic strains of Sm, both animal and human, and identify a putative role for animals as a reservoir in human infection. We phenotypically and genotypically characterized 61 Sm strains responsible for animal infections (mainly respiratory tract infections in horses) from a French nationwide veterinary laboratory network. We tested antimicrobial susceptibility and performed MLST and genogrouping using the concatenation of the seven housekeeping genes from the original MLST scheme. Excluding the eight untypeable strains owing to the lack of gene amplification, only 10 out of the 53 strains yielded a known ST (ST5, ST39, ST162, ST8, ST27, ST126, ST131). The genogroup distribution highlighted not only genogroups (genogroups 5 and 9) comprised exclusively of animal strains but also genogroups shared by human and animal strains. Interestingly, these shared genogroups were primarily groups 2 and 6, which have previously been identified as the two most frequent genogroups among human-pathogenic Sm strains, especially among respiratory pathogens. The antimicrobial susceptibility testing underlined the presence of acquired resistance: 18.8 and 7.5% of the tested isolates were resistant to the sulfonamide-trimethoprim combination and ciprofloxacin, respectively. Animal strains of Sm shared phylogenetic traits with some of the most successful human strains. The exact relationships between the human and animal strains, and the genetic support of these common traits, need to be determined.

  9. A model to explain plant growth promotion traits: a multivariate analysis of 2,211 bacterial isolates.

    Directory of Open Access Journals (Sweden)

    Pedro Beschoren da Costa

    Full Text Available Plant growth-promoting bacteria can greatly assist sustainable farming by improving plant health and biomass while reducing fertilizer use. The plant-microorganism-environment interaction is an open and complex system, and despite the active research in the area, patterns in root ecology are elusive. Here, we simultaneously analyzed the plant growth-promoting bacteria datasets from seven independent studies that shared a methodology for bioprospection and phenotype screening. The soil richness of the isolate's origin was classified by a Principal Component Analysis. A Categorical Principal Component Analysis was used to classify the soil richness according to isolate's indolic compound production, siderophores production and phosphate solubilization abilities, and bacterial genera composition. Multiple patterns and relationships were found and verified with nonparametric hypothesis testing. Including niche colonization in the analysis, we proposed a model to explain the expression of bacterial plant growth-promoting traits according to the soil nutritional status. Our model shows that plants favor interaction with growth hormone producers under rich nutrient conditions but favor nutrient solubilizers under poor conditions. We also performed several comparisons among the different genera, highlighting interesting ecological interactions and limitations. Our model could be used to direct plant growth-promoting bacteria bioprospection and metagenomic sampling.

  10. A primary assessment of the endophytic bacterial community in a xerophilous moss (Grimmia montana using molecular method and cultivated isolates

    Directory of Open Access Journals (Sweden)

    Xiao Lei Liu

    2014-01-01

    Full Text Available Investigating the endophytic bacterial community in special moss species is fundamental to understanding the microbial-plant interactions and discovering the bacteria with stresses tolerance. Thus, the community structure of endophytic bacteria in the xerophilous moss Grimmia montana were estimated using a 16S rDNA library and traditional cultivation methods. In total, 212 sequences derived from the 16S rDNA library were used to assess the bacterial diversity. Sequence alignment showed that the endophytes were assigned to 54 genera in 4 phyla (Proteobacteria, Firmicutes, Actinobacteria and Cytophaga/Flexibacter/Bacteroids. Of them, the dominant phyla were Proteobacteria (45.9% and Firmicutes (27.6%, the most abundant genera included Acinetobacter, Aeromonas, Enterobacter, Leclercia, Microvirga, Pseudomonas, Rhizobium, Planococcus, Paenisporosarcina and Planomicrobium. In addition, a total of 14 species belonging to 8 genera in 3 phyla (Proteobacteria, Firmicutes, Actinobacteria were isolated, Curtobacterium, Massilia, Pseudomonas and Sphingomonas were the dominant genera. Although some of the genera isolated were inconsistent with those detected by molecular method, both of two methods proved that many different endophytic bacteria coexist in G. montana. According to the potential functional analyses of these bacteria, some species are known to have possible beneficial effects on hosts, but whether this is the case in G. montana needs to be confirmed.

  11. Isolation of a bacterial consortium able to degrade the fungicide thiabendazole: the key role of a Sphingomonas phylotype.

    Science.gov (United States)

    Perruchon, Chiara; Chatzinotas, Antonis; Omirou, Michalis; Vasileiadis, Sotirios; Menkissoglou-Spiroudi, Urania; Karpouzas, Dimitrios G

    2017-05-01

    Thiabendazole (TBZ) is a fungicide used in fruit-packaging plants. Its application leads to the production of wastewaters requiring detoxification. In the absence of efficient treatment methods, biological depuration of these effluents could be a viable alternative. However, nothing is known regarding the microbial degradation of the recalcitrant and toxic to aquatics TBZ. We report the isolation, via enrichment cultures from a polluted soil, of the first bacterial consortium able to rapidly degrade TBZ and use it as a carbon source. Repeated efforts using various culture-dependent approaches failed to isolate TBZ-degrading bacteria in axenic cultures. Denaturating gradient gel electrophoresis (DGGE) and cloning showed that the consortium was composed of α-, β- and γ-Proteobacteria. Culture-independent methods including antibiotics-driven selection with DNA/RNA-DGGE, q-PCR and stable isotope probing (SIP)-DGGE identified a Sphingomonas phylotype (B13) as the key degrading member. Cross-feeding studies with structurally related chemicals showed that ring substituents of the benzimidazole moiety (thiazole or furan rings) favoured the cleavage of the imidazole moiety. LC-MS/MS analysis verified that TBZ degradation proceeds via cleavage of the imidazole moiety releasing thiazole-4-carboxamidine, which was not further transformed, and the benzoyl moiety, possibly as catechol, which was eventually consumed by the bacterial consortium as suggested by SIP-DGGE.

  12. Isolation and Structural Determination of an Anti Bacterial Constituent from the Leaves of Cassia alata Linn.

    OpenAIRE

    Barnali Paul; Prasenjit Mitra; Tanaya Ghosh; Ravinernath Salhan; Takhelmayum Amumachi Singh; Amit Chakrabarti; Sumanta Gupta; Basudeb Basu; Prasanta Kumar Mitra

    2013-01-01

    By different solvent extractions and chromatographic techniques an antibacterial constituent was isolated from leaves of Cassia alata Linn. Infra red spectroscopy, mass spectroscopy and nuclear magnetic resonance studies showed that the isolated compound was chemically 3,4 dihydroxy cinnamic acid. In vitro antibacterial activity of 3,4 dihydroxy cinnamic acid was studied against four Gram-positive and four Gram-negative bacteria using disc diffusion method. Minimum inhibitory concentration (M...

  13. Novel bacterial isolate from Permian groundwater, capable of aggregating potential biofuel-producing microalga Nannochloropsis oceanica IMET1.

    Science.gov (United States)

    Wang, Hui; Laughinghouse, Haywood D; Anderson, Matthew A; Chen, Feng; Willliams, Ernest; Place, Allen R; Zmora, Odi; Zohar, Yonathan; Zheng, Tianling; Hill, Russell T

    2012-03-01

    Increasing petroleum costs and climate change have resulted in microalgae receiving attention as potential biofuel producers. Little information is available on the diversity and functions of bacterial communities associated with biofuel-producing algae. A potential biofuel-producing microalgal strain, Nannochloropsis oceanica IMET1, was grown in Permian groundwater. Changes in the bacterial community structure at three temperatures were monitored by two culture-independent methods, and culturable bacteria were characterized. After 9 days of incubation, N. oceanica IMET1 began to aggregate and precipitate in cultures grown at 30°C, whereas cells remained uniformly distributed at 15°C and 25°C. The bacterial communities in cultures at 30°C changed markedly. Some bacteria isolated only at 30°C were tested for their potential for aggregating microalgae. A novel bacterium designated HW001 showed a remarkable ability to aggregate N. oceanica IMET1, causing microalgal cells to aggregate after 3 days of incubation, while the total lipid content of the microalgal cells was not affected. Direct interaction of HW001 and N. oceanica is necessary for aggregation. HW001 can also aggregate the microalgae N. oceanica CT-1, Tetraselmis suecica, and T. chuii as well as the cyanobacterium Synechococcus WH8007. 16S rRNA gene sequence comparisons indicated the great novelty of this strain, which exhibited only 89% sequence similarity with any previously cultured bacteria. Specific primers targeted to HW001 revealed that the strain originated from the Permian groundwater. This study of the bacterial communities associated with potential biofuel-producing microalgae addresses a little-investigated area of microalgal biofuel research and provides a novel approach to harvest biofuel-producing microalgae by using the novel bacterium strain HW001.

  14. Bacterial elongation factors EF-Tu, their mutants, chimeric forms, and domains: isolation and purification

    Czech Academy of Sciences Publication Activity Database

    Jonák, Jiří

    2007-01-01

    Roč. 849, 1-2 (2007), s. 141-153 ISSN 1570-0232 R&D Projects: GA AV ČR IAA5052206; GA AV ČR KJB500520503; GA MŠk 2B06065 Institutional research plan: CEZ:AV0Z50520514 Keywords : bacterial elongation factors EF-Tu, , G-domain * recombinant EF-Tus * preparation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.935, year: 2007

  15. Bacterial Isolates and Their Antimicrobial Susceptibility Patterns of Wound Infections among Inpatients and Outpatients Attending the University of Gondar Referral Hospital, Northwest Ethiopia

    Directory of Open Access Journals (Sweden)

    Aynalem Mohammed

    2017-01-01

    Full Text Available Background. The widespread uses of antibiotics, together with the length of time over which they have been available, have led to the emergence of resistant bacterial pathogens contributing to morbidity and mortality. This study was aimed to assess bacterial isolates and their drug susceptibility patterns from inpatients and outpatients with pus and/or wound discharge. Methods. A cross-sectional study was conducted at the University of Gondar Referral Hospital from March to May, 2014. Wound swab samples were collected from each study participant and inoculated into appropriate media. The bacterial pathogens were identified using standard microbiological methods. Antimicrobial susceptibility tests were performed using disk diffusion technique following Kirby-Bauer method. Results. A total of 137 study subjects were included in the study with bacterial isolation rate of 115 (83.9%. Of all, 81 (59.1% were males. Seventy-seven (57% of the isolates were Gram-negative and 59 (43% were Gram-positive. From the total isolates, Staphylococcus aureus was the most predominant isolate 39/115 (34% followed by Klebsiella species (13%, coagulase negative staphylococci spp. (12% and Pseudomonas aeruginosa. Gram-positive isolates were resistant to ampicillin (86.4%, amoxicillin (83%, penicillin (81.3%, oxacillin (74.6%, and tetracycline (59.4%, while Gram-negative isolates were resistant to amoxicillin (97.4%, ampicillin (94.8%, tetracycline (72.7%, trimethoprim/sulfamethoxazole (66%, and chloramphenicol (54.5%. Conclusion. High prevalence of bacterial isolates was found, Staphylococcus aureus being the most dominant. High rates of multiple drug resistance pathogens to the commonly used antimicrobial agents were isolated. Therefore, concerned bodies should properly monitor the choice of antibiotics to be used as prophylaxis and empiric treatment in the study area.

  16. Siderophores of Stenotrophomonas maltophilia: detection and determination of their chemical nature Sideróforos de Stenotrophomonas maltophilia: detección y determinación de su naturaleza química

    Directory of Open Access Journals (Sweden)

    Carlos A. García

    2012-09-01

    Full Text Available Stenotrophomonas maltophilia is an emerging nosocomial pathogen. Despite the broad spectrum of syndromes associated with S. maltophilia infections, little is known about its virulence factors, including siderophore production. The aims of this work were to detect S. maltophilia siderophores and to determine their chemical nature. We studied 31 S. maltophilia isolates from device-associated infections, recovered over the period 2006-2011 at Hospital de Clínicas José de San Martin, Buenos Aires, Argentina, and the strain K279a, whose genome has been fully sequenced. The production of siderophores was screened by the chrome azurol S (CAS agar assay, previously modified to detect siderophores in this species. When grown on modified CAS agar plates, all the clinical isolates and K279a were CAS-positive for siderophore production. In order to determine the chemical nature of siderophores, the Csáky (hydroxamate-type and Arnow (catechol-type assays were used. All S. maltophilia isolates produced catechol-type siderophores, but hydroxamate-type siderophores were not detected.Stenotrophomonas maltophilia es un patógeno nosocomial emergente. A pesar de la variedad de infecciones que produce, poco se conoce acerca de sus factores de virulencia, incluida la producción de sideróforos. Nuestros objetivos fueron detectar sideróforos de S. maltophilia y determinar su naturaleza química. Se estudiaron 31 aislamientos provenientes de infecciones asociadas al uso de dispositivos médicos y la cepa K279a, cuyo genoma ha sido completamente secuenciado. Los aislamientos provenientes de infecciones se obtuvieron de pacientes asistidos en el Hospital de Clínicas José de San Martín (Buenos Aires, Argentina en el período 2006- 2011. Como método de tamizaje se empleó la técnica chrome azurol S (CAS en placa, luego de implementar una modificación para detectar sideróforos en esta especie. Dicha modificación permitió detectar la producción de sider

  17. Bacterial Community Analysis, New Exoelectrogen Isolation and Enhanced Performance of Microbial Electrochemical Systems Using Nano-Decorated Anodes

    Science.gov (United States)

    Xu, Shoutao

    Microbial electrochemical systems (MESs) have attracted much research attention in recent years due to their promising applications in renewable energy generation, bioremediation, and wastewater treatment. In a MES, microorganisms interact with electrodes via electrons, catalyzing oxidation and reduction reactions at the anode and the cathode. The bacterial community of a high power mixed consortium MESs (maximum power density is 6.5W/m2) was analyzed by using denature gradient gel electrophoresis (DGGE) and 16S DNA clone library methods. The bacterial DGGE profiles were relatively complex (more than 10 bands) but only three brightly dominant bands in DGGE results. These results indicated there are three dominant bacterial species in mixed consortium MFCs. The 16S DNA clone library method results revealed that the predominant bacterial species in mixed culture is Geobacter sp (66%), Arcobacter sp and Citrobacter sp. These three bacterial species reached to 88% of total bacterial species. This result is consistent with the DGGE result which showed that three bright bands represented three dominant bacterial species. Exoelectrogenic bacterial strain SX-1 was isolated from a mediator-less microbial fuel cell by conventional plating techniques with ferric citrate as electron acceptor under anaerobic conditions. Phylogenetic analysis of the 16S rDNA sequence revealed that it was related to the members of Citrobacter genus with Citrobacter sp. sdy-48 being the most closely related species. The bacterial strain SX-1 produced electricity from citrate, acetate, glucose, sucrose, glycerol, and lactose in MFCs with the highest current density of 205 mA/m2 generated from citrate. Cyclic voltammetry analysis indicated that membrane associated proteins may play an important role in facilitating electron transfer from the bacteria to the electrode. This is the first study that demonstrates that Citrobacter species can transfer electrons to extracellular electron acceptors

  18. Comparison of Lactobacillus crispatus isolates from Lactobacillus-dominated vaginal microbiomes with isolates from microbiomes containing bacterial vaginosis-associated bacteria

    Science.gov (United States)

    Abdelmaksoud, Abdallah A.; Koparde, Vishal N.; Sheth, Nihar U.; Serrano, Myrna G.; Glascock, Abigail L.; Fettweis, Jennifer M.; Strauss, Jerome F.; Buck, Gregory A.

    2016-01-01

    Vaginal lactobacilli can inhibit colonization by and growth of other bacteria, thereby preventing development of bacterial vaginosis (BV). Amongst the lactobacilli, Lactobacillus crispatus appears to be particularly effective at inhibiting growth of BV-associated bacteria. Nonetheless, some women who are colonized with this species can still develop clinical BV. Therefore, we sought to determine whether strains of L. crispatus that colonize women with lactobacilli-dominated vaginal microbiomes are distinct from strains that colonize women who develop BV. The genomes of L. crispatus isolates from four women with lactobacilli-dominated vaginal microbiomes ( bacteria (>12 % 16S rRNA reads from bacterial taxa associated with BV) were sequenced and compared. Lactic acid production by the different strains was quantified. Phage induction in the strains was also analysed. There was considerable genetic diversity between strains, and several genes were exclusive to either the strains from Lactobacillus-dominated microbiomes or those containing BV-associated bacteria. Overall, strains from microbiomes dominated by lactobacilli did not differ from strains from microbiomes containing BV-associated bacteria with respect to lactic acid production. All of the strains contained multiple phage, but there was no clear distinction between the presence or absence of BV-associated bacteria with respect to phage-induced lysis. Genes found to be exclusive to the Lactobacillus-dominated versus BV-associated bacteria-containing microbiomes could play a role in the maintenance of vaginal health and the development of BV, respectively. PMID:26747455

  19. Environmental monitoring of bacterial contamination and antibiotic resistance patterns of the fecal coliforms isolated from Cauvery River, a major drinking water source in Karnataka, India.

    Science.gov (United States)

    Skariyachan, Sinosh; Mahajanakatti, Arpitha Badarinath; Grandhi, Nisha Jayaprakash; Prasanna, Akshatha; Sen, Ballari; Sharma, Narasimha; Vasist, Kiran S; Narayanappa, Rajeswari

    2015-05-01

    The present study focuses prudent elucidation of microbial pollution and antibiotic sensitivity profiling of the fecal coliforms isolated from River Cauvery, a major drinking water source in Karnataka, India. Water samples were collected from ten hotspots during the year 2011-2012. The physiochemical characteristics and microbial count of water samples collected from most of the hotspots exhibited greater biological oxygen demand and bacterial count especially coliforms in comparison with control samples (p ≤ 0.01). The antibiotic sensitivity testing was performed using 48 antibiotics against the bacterial isolates by disk-diffusion assay. The current study showed that out of 848 bacterial isolates, 93.51% (n = 793) of the isolates were found to be multidrug-resistant to most of the current generation antibiotics. Among the major isolates, 96.46% (n = 273) of the isolates were found to be multidrug-resistant to 30 antibiotics and they were identified to be Escherichia coli by 16S rDNA gene sequencing. Similarly, 93.85% (n = 107), 94.49% (n = 103), and 90.22% (n = 157) of the isolates exhibited multiple drug resistance to 32, 40, and 37 antibiotics, and they were identified to be Enterobacter cloacae, Pseudomonas trivialis, and Shigella sonnei, respectively. The molecular studies suggested the prevalence of bla TEM genes in all the four isolates and dhfr gene in Escherichia coli and Sh. sonnei. Analogously, most of the other Gram-negative bacteria were found to be multidrug-resistant and the Gram-positive bacteria, Staphylococcus spp. isolated from the water samples were found to be methicillin and vancomycin-resistant Staphylococcus aureus. This is probably the first study elucidating the bacterial pollution and antibiotic sensitivity profiling of fecal coliforms isolated from River Cauvery, Karnataka, India.

  20. Chronic pulmonary infection with Stenotrophomonas maltophilia and lung function in patients with cystic fibrosis

    DEFF Research Database (Denmark)

    Dalbøge, C S; Hansen, C R; Pressler, T

    2011-01-01

    Background The clinical consequences of chronic Stenotrophomonas maltophilia infection in cystic fibrosis (CF) patient are still unclear. Method All patients treated in the Copenhagen CF centre (N=278) from 1 January 2008 to 31 December 2009 were included. Each patient chronically infected with S...

  1. Chitinase genes revealed and compared in bacterial isolates, DNA extracts and a metagenomic library from a phytopathogen suppressive soil

    Energy Technology Data Exchange (ETDEWEB)

    Hjort, K.; Bergstrom, M.; Adesina, M.F.; Jansson, J.K.; Smalla, K.; Sjoling, S.

    2009-09-01

    Soil that is suppressive to disease caused by fungal pathogens is an interesting source to target for novel chitinases that might be contributing towards disease suppression. In this study we screened for chitinase genes, in a phytopathogen-suppressive soil in three ways: (1) from a metagenomic library constructed from microbial cells extracted from soil, (2) from directly extracted DNA and (3) from bacterial isolates with antifungal and chitinase activities. Terminal-restriction fragment length polymorphism (T-RFLP) of chitinase genes revealed differences in amplified chitinase genes from the metagenomic library and the directly extracted DNA, but approximately 40% of the identified chitinase terminal-restriction fragments (TRFs) were found in both sources. All of the chitinase TRFs from the isolates were matched to TRFs in the directly extracted DNA and the metagenomic library. The most abundant chitinase TRF in the soil DNA and the metagenomic library corresponded to the TRF{sup 103} of the isolate, Streptomyces mutomycini and/or Streptomyces clavifer. There were good matches between T-RFLP profiles of chitinase gene fragments obtained from different sources of DNA. However, there were also differences in both the chitinase and the 16S rRNA gene T-RFLP patterns depending on the source of DNA, emphasizing the lack of complete coverage of the gene diversity by any of the approaches used.

  2. Resistance and inactivation kinetics of bacterial strains isolated from the non-chlorinated and chlorinated effluents of a WWTP.

    Science.gov (United States)

    Martínez-Hernández, Sylvia; Vázquez-Rodríguez, Gabriela A; Beltrán-Hernández, Rosa I; Prieto-García, Francisco; Miranda-López, José M; Franco-Abuín, Carlos M; Álvarez-Hernández, Alejandro; Iturbe, Ulises; Coronel-Olivares, Claudia

    2013-08-06

    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.

  3. 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.

  4. Susceptibility of bacterial isolates from community-acquired infections in sub-Saharan Africa and Asia to macrolide antibiotics.

    Science.gov (United States)

    Lubell, Yoel; Turner, Paul; Ashley, Elizabeth A; White, Nicholas J

    2011-10-01

    To review the literature on the susceptibility of common community pathogens in sub-Saharan Africa and Asia to the macrolide antibiotics. Inclusion criteria required that isolates were collected since 2004 to ensure results were of contemporary relevance. The data were aggregated by region, age group and sterility of site of culture sample. A total of 51 studies were identified, which reported the macrolide antimicrobial susceptibilities of common bacterial pathogens isolated since 2004. In general, there was less macrolide resistance in African than in Asian isolates. Most African studies reported high levels of macrolide susceptibility in Streptococcus pneumoniae, whereas most Chinese studies reported high levels of resistance. There was very little information available for Gram-negative organisms. Susceptibility of the pneumococcus to macrolides in SSA remains high in many areas, and good activity of azithromycin has been shown against Salmonellae spp. in Asia. In urban areas where high antibiotic consumption is prevalent, there was evidence of increased resistance to macrolides. However, there is no information on susceptibility from large areas in both continents. © 2011 Blackwell Publishing Ltd.

  5. ‘Bacillus massiliglaciei’, a new bacterial species isolated from Siberian permafrost

    Directory of Open Access Journals (Sweden)

    P. Afouda

    2017-01-01

    Full Text Available We describe here the main characteristics of a new species isolated from Siberian permafrost dated around 10 million years. This species was named ‘Bacillus massiliglaciei’ strain Marseille-P2600T (= CSUR P2600=DSM 102861.

  6. ‘Bacteroides cutis,’ a new bacterial species isolated from human skin

    Directory of Open Access Journals (Sweden)

    S. Belkacemi

    2018-03-01

    Full Text Available We report the main characteristics of ‘Bacteroides cutis’ sp. nov., strain Marseille-P4118T (= CSUR P4118, a new species within the genus Bacteroides. This strain was isolated from a skin sample of a 75-year-old man from Marseille.

  7. ‘Actinotignum timonense’ sp. nov., a new bacterial species isolated from a human urine sample

    Directory of Open Access Journals (Sweden)

    S. Brahimi

    2017-03-01

    Full Text Available We report here the main characteristics of ‘Actinotignum timonense’ strain Marseille-P2803T (= CSUR P2803 that was isolated from the urine sample of a 59-year-old man with end-stage renal disease.

  8. Pacaella massiliensis gen. nov., sp. nov., a new bacterial species isolated from the human gut

    Directory of Open Access Journals (Sweden)

    S. Ndongo

    2017-03-01

    Full Text Available Herein, we report the main characteristics of a new species named Pacaella massiliensis gen. nov., sp. nov., strain Marseille-P2670T (CSUR P2670 that was isolated from the gut microbiota of a 45-year-old French patient.

  9. Anti-bacterial activity of Extract of Crinum jagus bulb against Isolates ...

    African Journals Online (AJOL)

    Crinum jagus plant has been reportedly used for treatment of infectious diseases in Nigeria. In this study, the antibacterial activity of the crude extract and chromatographic fractions from the bulb of Crinium jagus against Mycobacterium tuberculosis isolates was investigated using Lowenstein-Jensen medium (LJ) and ...

  10. Biosorption of Zinc (Zn) and lead (Pb) by metal resistant bacterial isolate from mining tail

    Energy Technology Data Exchange (ETDEWEB)

    Bautista Hernandez, D. A.; Carranza Alvarado, M.; Fernandez Linares, L.; Ramirez Landy, I.

    2009-07-01

    The use of microbial biomass in the removal of metals in solution, mainly of low concentrations (100 mg L{sup -}1), present advantages in relation to the physicochemical methods. The resistant microorganisms are potential bio sorbents. The objective of the present study was the isolation, starting from mining tail, of strains with capacity of metal bio sorption (Zn and Pb). (Author)

  11. Biosorption of Zinc (Zn) and lead (Pb) by metal resistant bacterial isolate from mining tail

    International Nuclear Information System (INIS)

    Bautista Hernandez, D. A.; Carranza Alvarado, M.; Fernandez Linares, L.; Ramirez Landy, I.

    2009-01-01

    The use of microbial biomass in the removal of metals in solution, mainly of low concentrations (100 mg L - 1), present advantages in relation to the physicochemical methods. The resistant microorganisms are potential bio sorbents. The objective of the present study was the isolation, starting from mining tail, of strains with capacity of metal bio sorption (Zn and Pb). (Author)

  12. Isolation and Characterization of Rhamnolipid-Producing Bacterial Strains from a Biodiesel Facility

    Science.gov (United States)

    Novel strains of rhamnolipid-producing bacteria were isolated from soils at a biodiesel facility on the basis of their ability to grow on glycerol as a sole carbon source. Strains were identified as Acinetobacter calcoaceticus, Enterobacter asburiae, E. hormaecheii, Pantoea stewartii and Pseudomona...

  13. Antibiotic Resistant Bacterial Isolates from Captive Green Turtles and In Vitro Sensitivity to Bacteriophages

    Directory of Open Access Journals (Sweden)

    Alessandro Delli Paoli Carini

    2017-01-01

    Full Text Available This study aimed to test multidrug resistant isolates from hospitalised green turtles (Chelonia mydas and their environment in North Queensland, Australia, for in vitro susceptibility to bacteriophages. Seventy-one Gram-negative bacteria were isolated from green turtle eye swabs and water samples. Broth microdilution tests were used to determine antibiotic susceptibility. All isolates were resistant to at least two antibiotics, with 24% being resistant to seven of the eight antibiotics. Highest resistance rates were detected to enrofloxacin (77% and ampicillin (69.2%. More than 50% resistance was also found to amoxicillin/clavulanic acid (62.5%, ceftiofur (53.8%, and erythromycin (53.3%. All the enriched phage filtrate mixtures resulted in the lysis of one or more of the multidrug resistant bacteria, including Vibrio harveyi and V. parahaemolyticus. These results indicate that antibiotic resistance is common in Gram-negative bacteria isolated from hospitalised sea turtles and their marine environment in North Queensland, supporting global concern over the rapid evolution of multidrug resistant genes in the environment. Using virulent bacteriophages as antibiotic alternatives would not only be beneficial to turtle health but also prevent further addition of multidrug resistant genes to coastal waters.

  14. A study of bacterial isolates from corneal specimens and their antibiotic resistance profile

    International Nuclear Information System (INIS)

    Begum, N. N.; Al-Khattaf, Abdulaziz S.; Yeboah, E. A.; Kambal, Abdel-Majed M.; Al-Mansouri, Samir M.

    2006-01-01

    We aim to examine the spectrum of bacteria causing corneal infections and their antibiotic susceptibility patterns. This will serve as a guideline for empiric therapy of corneal infections. We conducted the study over a period of 18 months from March 2001 through December 2002 in King Abdul-Aziz University Hospital, Riyadh, Kingdom of Saudi Arabia. Corneal specimens taken from 200 patients were inoculated directly onto different types of media. The isolates were identified and then tested against the appropriate topical or systemic antibiotics. Sixty-seven (33.5%) of the total specimens were culture positive and 133 (66.5%) were culture negative. Fourteen (7%) of these showed organisms in the Gram stained smears and correlated well with the culture reports. Of the 67 positive cultures, 53 (79.1%) were Gram-positive bacteria mostly coagulase-negative Staphylococci 29 (43.3%) followed by Streptococcus pneumoniae (S. pneumoniae) 13 (19.4%). Among Gram-negative bacteria 14 (20.9%), Pseudomonas aeruginosa (P. aeruginosa) 10 (14.9%) was the predominant isolate. All the isolates were sensitive to ofloxacin and the commonly used ocular antibiotics. All the isolated bacteria were sensitive to ofloxacin, a fluoroquinolone. Having marked potency for broad-spectrum activity against both Gram-positive and Gram-negative bacteria, make the fluoroquinolones especially the newer generations, a potential single drug therapy for corneal infections. (author)

  15. Biodegradation of lindane, methyl parathion and carbofuran by various enriched bacterial isolates.

    Science.gov (United States)

    Krishna, K Rama; Philip, Ligy

    2008-02-01

    In the present study, lindane (1,2,3,4,5,6-hexachlorocyclohexane), methyl parathion (O-dimethylO-(4-nitro-phenyl) phosphorothioate) and carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) degradation potential of different enriched bacterial cultures were evaluated under various environmental conditions. Enriched cultures behaved differently with different pesticides. Degradation was more in a facultative anaerobic condition as compared to that in aerobic condition. A specific pesticide enriched culture showed maximum degradation of that pesticide irrespective of pesticides and environmental conditions. Lindane and endosulfan enriched cultures behaved almost similarly. Degradation of lindane by lindane enriched cultures was 75 +/- 3% in aerobic co-metabolic process whereas 78 +/- 5% of lindane degradation occurred in anaerobic co-metabolic process. Degradation of methyl parathion by methyl parathion enriched culture was 87 +/- 1% in facultative anaerobic condition. In almost all the cases, many intermediate metabolites were observed. However, many of these metabolites disappeared after 4-6 weeks of incubation. Mixed pesticide-enriched culture degraded all the three pesticides more effectively as compared to specific pesticide- enriched cultures. It can be inferred from the results that a bacterial consortium enriched with a mixture of all the possible pesticides that are present in the site seems to be a better option for the effective bioremediation of multi-pesticide contaminated site.

  16. Growth of 48 built environment bacterial isolates on board the International Space Station (ISS

    Directory of Open Access Journals (Sweden)

    David A. Coil

    2016-03-01

    Full Text Available Background. While significant attention has been paid to the potential risk of pathogenic microbes aboard crewed spacecraft, the non-pathogenic microbes in these habitats have received less consideration. Preliminary work has demonstrated that the interior of the International Space Station (ISS has a microbial community resembling those of built environments on Earth. Here we report the results of sending 48 bacterial strains, collected from built environments on Earth, for a growth experiment on the ISS. This project was a component of Project MERCCURI (Microbial Ecology Research Combining Citizen and University Researchers on ISS. Results. Of the 48 strains sent to the ISS, 45 of them showed similar growth in space and on Earth using a relative growth measurement adapted for microgravity. The vast majority of species tested in this experiment have also been found in culture-independent surveys of the ISS. Only one bacterial strain showed significantly different growth in space. Bacillus safensis JPL-MERTA-8-2 grew 60% better in space than on Earth. Conclusions. The majority of bacteria tested were not affected by conditions aboard the ISS in this experiment (e.g., microgravity, cosmic radiation. Further work on Bacillus safensis could lead to interesting insights on why this strain grew so much better in space.

  17. Antimicrobial activity of aqueous extracts from four plants on bacterial isolates from periodontitis patients.

    Science.gov (United States)

    Arbia, Leila; Chikhi-Chorfi, Nassima; Betatache, Ilhem; Pham-Huy, Chuong; Zenia, Selma; Mameri, Nabil; Drouiche, Nadjib; Lounici, Hakim

    2017-05-01

    Four aqueous extracts of different plant organs are the following: Artemisia herba-alba, Opuntia ficus-indica, Camellia sinensis and Phlomis crinita were evaluated against two bacterial strains: Porphyromonas gingivalis and Prevotella intermedia, which are implicated in periodontal diseases. By using a disc method, these plant extracts demonstrated powerful bacterial activity against these Gram-negative strains. The minimum inhibitory concentration values of the four plant extracts varied between 0.03 and 590.82 mg/ml for the microbes. Another assay using commercial antibiotics and antibacterials as positive controls was also conducted. Values obtained after statistical analysis of inhibition diameters of all plant extracts demonstrated that for P. gingivalis, the aqueous extracts of A. herba-alba and O. ficus-indica were most effective, followed by those of C. sinensis and P. crinita. For P. intermedia, aqueous extracts of O. ficus-indica and C. sinensis appeared to be more efficient with significantly different (P > 0.05) inhibition diameters, followed by those of O. ficus-indica and P. crinita. In summary, the statistical results reveal that these plant extracts exert stronger antibacterial activity on P. intermedia germ as compared to P. gingivalis.

  18. Related antimicrobial resistance genes detected in different bacterial species co-isolated from swine fecal samples.

    Science.gov (United States)

    Frye, Jonathan G; Lindsey, Rebecca L; Meinersmann, Richard J; Berrang, Mark E; Jackson, Charlene R; Englen, Mark D; Turpin, Jennifer B; Fedorka-Cray, Paula J

    2011-06-01

    A potential factor leading to the spread of antimicrobial resistance (AR) in bacteria is the horizontal transfer of resistance genes between bacteria in animals or their environment. To investigate this, swine fecal samples were collected on-farm and cultured for Escherichia coli, Salmonella enterica, Campylobacter spp., and Enterococcus spp. which are all commonly found in swine. Forty-nine of the samples from which all four bacteria were recovered were selected yielding a total of 196 isolates for analysis. Isolates were tested for antimicrobial susceptibility followed by hybridization to a DNA microarray designed to detect 775 AR-related genes. E. coli and Salmonella isolated from the same fecal sample had the most AR genes in common among the four bacteria. Genes detected encoded resistance to aminoglycosides (aac(3), aadA1, aadB, and strAB), β-lactams (ampC, ampR, and bla(TEM)), chloramphenicols (cat and floR), sulfanillic acid (sul1/sulI), tetracyclines (tet(A), tet(D), tet(C), tet(G), and tet(R)), and trimethoprim (dfrA1 and dfh). Campylobacter coli and Enterococcus isolated from the same sample frequently had tet(O) and aphA-3 genes detected in common. Almost half (47%) of E. coli and Salmonella isolated from the same fecal sample shared resistance genes at a significant level (χ², p genes between these bacteria or there may be a common source of AR genes in the swine environment for E. coli and Salmonella.

  19. Degradation of nicosulfuron by a novel isolated bacterial strain Klebsiella sp. Y1: condition optimization, kinetics and degradation pathway.

    Science.gov (United States)

    Wang, Lin; Zhang, Xiaolin; Li, Yongmei

    2016-01-01

    A novel bacterial strain Klebsiella sp. Y1 was isolated from the soil of a constructed wetland, and it was identified based on the 16S rDNA sequence analysis. The co-metabolic degradation of nicosulfuron with glucose by Klebsiella sp. Y1 was investigated. The response surface methodology analysis indicated that the optimal pH and temperature were 7.0 and 35 °C, respectively, for the degradation of nicosulfuron. Under the optimal conditions, the degradation of nicosulfuron fitted Haldane kinetics model well. The removal of nicosulfuron was triggered by the acidification of glucose, which accelerated the hydrolysis of nicosulfuron. Then, the C-N bond of the sulfonylurea bridge was attacked and cleaved. Finally, the detected intermediate 2-amino-4,6-dimethoxypyrimidine was further biodegraded.

  20. Draft Genomes, Phylogenetic Reconstruction, and Comparative Genomics of Two Novel Cohabiting Bacterial Symbionts Isolated from Frankliniella occidentalis.

    Science.gov (United States)

    Facey, Paul D; Méric, Guillaume; Hitchings, Matthew D; Pachebat, Justin A; Hegarty, Matt J; Chen, Xiaorui; Morgan, Laura V A; Hoeppner, James E; Whitten, Miranda M A; Kirk, William D J; Dyson, Paul J; Sheppard, Sam K; Del Sol, Ricardo

    2015-07-15

    Obligate bacterial symbionts are widespread in many invertebrates, where they are often confined to specialized host cells and are transmitted directly from mother to progeny. Increasing numbers of these bacteria are being characterized but questions remain about their population structure and evolution. Here we take a comparative genomics approach to investigate two prominent bacterial symbionts (BFo1 and BFo2) isolated from geographically separated populations of western flower thrips, Frankliniella occidentalis. Our multifaceted approach to classifying these symbionts includes concatenated multilocus sequence analysis (MLSA) phylogenies, ribosomal multilocus sequence typing (rMLST), construction of whole-genome phylogenies, and in-depth genomic comparisons. We showed that the BFo1 genome clusters more closely to species in the genus Erwinia, and is a putative close relative to Erwinia aphidicola. BFo1 is also likely to have shared a common ancestor with Erwinia pyrifoliae/Erwinia amylovora and the nonpathogenic Erwinia tasmaniensis and genetic traits similar to Erwinia billingiae. The BFo1 genome contained virulence factors found in the genus Erwinia but represented a divergent lineage. In contrast, we showed that BFo2 belongs within the Enterobacteriales but does not group closely with any currently known bacterial species. Concatenated MLSA phylogenies indicate that it may have shared a common ancestor to the Erwinia and Pantoea genera, and based on the clustering of rMLST genes, it was most closely related to Pantoea ananatis but represented a divergent lineage. We reconstructed a core genome of a putative common ancestor of Erwinia and Pantoea and compared this with the genomes of BFo bacteria. BFo2 possessed none of the virulence determinants that were omnipresent in the Erwinia and Pantoea genera. Taken together, these data are consistent with BFo2 representing a highly novel species that maybe related to known Pantoea. © The Author(s) 2015. Published by

  1. Globally dispersed mobile drug-resistance genes in gram-negative bacterial isolates from patients with bloodstream infections in a US urban general hospital.

    Science.gov (United States)

    Adams-Sapper, S; Sergeevna-Selezneva, J; Tartof, S; Raphael, E; Diep, B An; Perdreau-Remington, F; Riley, L W

    2012-07-01

    Mobile drug-resistance genes with identical nucleic acid sequences carried by multidrug-resistant Escherichia coli strains that cause community-acquired infections are becomingly increasingly dispersed worldwide. Over a 2-year period, we analysed gram-negative bacterial (GNB) pathogens from the blood of inpatients at an urban public hospital to determine what proportion of these isolates carried such globally dispersed drug-resistance genes. Of 376 GNB isolates, 167 (44 %) were Escherichia coli, 50 (13 %) were Klebsiella pneumoniae, 25 (7 %) were Pseudomonas aeruginosa, 25 (7 %) were Proteus mirabilis and 20 (5 %) were Enterobacter cloacae; the remainder (24 %) comprised 26 different GNB species. Among E. coli isolates, class 1 integrons were detected in 64 (38 %). The most common integron gene cassette configuration was dfrA17-aadA5, found in 30 (25 %) of 119 drug-resistant E. coli isolates and in one isolate of Moraxella morganii. Extended-spectrum β-lactamase (ESBL) genes were found in 16 E. coli isolates (10 %). These genes with identical sequences were found in nearly 40 % of bloodstream E. coli isolates in the study hospital, as well as in a variety of bacterial species from clinical and non-clinical sources worldwide. Thus, a substantial proportion of bloodstream infections among hospitalized patients were caused by E. coli strains carrying drug-resistance genes that are dispersed globally in a wide variety of bacterial species.

  2. Diversity of Clinical and Environmental Isolates of Vibrio cholerae in Natural Transformation and Contact-Dependent Bacterial Killing Indicative of Type VI Secretion System Activity.

    Science.gov (United States)

    Bernardy, Eryn E; Turnsek, Maryann A; Wilson, Sarah K; Tarr, Cheryl L; Hammer, Brian K

    2016-05-01

    The bacterial pathogen Vibrio cholerae can occupy both the human gut and aquatic reservoirs, where it may colonize chitinous surfaces that induce the expression of factors for three phenotypes: chitin utilization, DNA uptake by natural transformation, and contact-dependent bacterial killing via a type VI secretion system (T6SS). In this study, we surveyed a diverse set of 53 isolates from different geographic locales collected over the past century from human clinical and environmental specimens for each phenotype outlined above. The set included pandemic isolates of serogroup O1, as well as several serogroup O139 and non-O1/non-O139 strains. We found that while chitin utilization was common, only 22.6% of the isolates tested were proficient at chitin-induced natural transformation, suggesting that transformation is expendable. Constitutive contact-dependent killing of Escherichia coli prey, which is indicative of a functional T6SS, was rare among clinical isolates (only 4 of 29) but common among environmental isolates (22 of 24). These results bolster the pathoadaptive model in which tight regulation of T6SS-mediated bacterial killing is beneficial in a human host, whereas constitutive killing by environmental isolates may give a competitive advantage in natural settings. Future sequence analysis of this set of diverse isolates may identify previously unknown regulators and structural components for both natural transformation and T6SS. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Diversity of Clinical and Environmental Isolates of Vibrio cholerae in Natural Transformation and Contact-Dependent Bacterial Killing Indicative of Type VI Secretion System Activity

    Science.gov (United States)

    Bernardy, Eryn E.; Turnsek, Maryann A.; Wilson, Sarah K.; Tarr, Cheryl L.

    2016-01-01

    The bacterial pathogen Vibrio cholerae can occupy both the human gut and aquatic reservoirs, where it may colonize chitinous surfaces that induce the expression of factors for three phenotypes: chitin utilization, DNA uptake by natural transformation, and contact-dependent bacterial killing via a type VI secretion system (T6SS). In this study, we surveyed a diverse set of 53 isolates from different geographic locales collected over the past century from human clinical and environmental specimens for each phenotype outlined above. The set included pandemic isolates of serogroup O1, as well as several serogroup O139 and non-O1/non-O139 strains. We found that while chitin utilization was common, only 22.6% of the isolates tested were proficient at chitin-induced natural transformation, suggesting that transformation is expendable. Constitutive contact-dependent killing of Escherichia coli prey, which is indicative of a functional T6SS, was rare among clinical isolates (only 4 of 29) but common among environmental isolates (22 of 24). These results bolster the pathoadaptive model in which tight regulation of T6SS-mediated bacterial killing is beneficial in a human host, whereas constitutive killing by environmental isolates may give a competitive advantage in natural settings. Future sequence analysis of this set of diverse isolates may identify previously unknown regulators and structural components for both natural transformation and T6SS. PMID:26944842

  4. Isolate PM1 populations are dominant and novel methyl tert-butyl ether-degrading bacterial in compost biofilter enrichments.

    Science.gov (United States)

    Bruns, M A; Hanson, J R; Mefford, J; Scow, K M

    2001-03-01

    The gasoline additive MTBE, methyl tert-butyl ether, is a widespread and persistent groundwater contaminant. MTBE undergoes rapid mineralization as the sole carbon and energy source of bacterial strain PM1, isolated from an enrichment culture of compost biofilter material. In this report, we describe the results of microbial community DNA profiling to assess the relative dominance of isolate PM1 and other bacterial strains cultured from the compost enrichment. Three polymerase chain reaction (PCR)-based profiling approaches were evaluated: denaturing gradient gel electrophoresis (DGGE) analysis of 230 bp 16S rDNA fragments; thermal gradient gel electrophoresis (TGGE) analysis of 575 bp 16S rDNA fragments; and non-denaturing polyacrylamide gel electrophoresis of 300-1,500 bp fragments containing 16S/23S ribosomal intergenic transcribed spacer (ITS) regions. Whereas all three DNA profiling approaches indicated that PM1-like bands predominated in mixtures from MTBE-grown enrichments, ITS profiling provided the most abundant and specific sequence data to confirm strain PM1's presence in the enrichment. Moreover, ITS profiling did not produce non-specific PCR products that were observed with T/DGGE. A further advantage of ITS community profiling over other methods requiring restriction digestion (e.g. terminal restriction fragment length polymorphisms) was that it did not require an additional digestion step or the use of automated sequencing equipment. ITS bands, excised from similar locations in profiles of the enrichment and PM1 pure culture, were 99.9% identical across 750 16S rDNA positions and 100% identical across 691 spacer positions. BLAST comparisons of nearly full-length 16S rDNA sequences showed 96% similarity between isolate PM1 and representatives of at least four different genera in the Leptothrix subgroup of the beta-Proteobacteria (Aquabacterium, Leptothrix, Rubrivivax and Ideonella). Maximum likelihood and parsimony analyses of 1,249 nucleotide

  5. Biodegradation of marine crude oil pollution using a salt-tolerant bacterial consortium isolated from Bohai Bay, China.

    Science.gov (United States)

    Li, Xinfei; Zhao, Lin; Adam, Mohamed

    2016-04-15

    This study aims at constructing an efficient bacterial consortium to biodegrade crude oil spilled in China's Bohai Sea. In this study, TCOB-1 (Ochrobactrum), TCOB-2 (Brevundimonas), TCOB-3 (Brevundimonas), TCOB-4 (Bacillus) and TCOB-5 (Castellaniella) were isolated from Bohai Bay. Through the analysis of hydrocarbon biodegradation, TCOB-4 was found to biodegrade more middle-chain n-alkanes (from C17 to C23) and long-chain n-alkanes (C31-C36). TCOB-5 capable to degrade more n-alkanes including C24-C30 and aromatics. On the basis of complementary advantages, TCOB-4 and TCOB-5 were chosen to construct a consortium which was capable of degrading about 51.87% of crude oil (2% w/v) after 1week of incubation in saline MSM (3% NaCl). It is more efficient compared with single strain. In order to biodegrade crude oil, the construction of bacterial consortia is essential and the principle of complementary advantages could reduce competition between microbes. Copyright © 2016. Published by Elsevier Ltd.

  6. Comparative Antibacterial Efficacy of Vitellaria paradoxa (Shea Butter Tree Extracts Against Some Clinical Bacterial Isolates

    Directory of Open Access Journals (Sweden)

    Kamoldeen Abiodun AJIJOLAKEWU

    2015-09-01

    Full Text Available The antibacterial activities of the ethanolic extracts of seed, leaf and stem bark of Vitellaria paradoxa were investigated. The extracts were tested against three clinical bacterial pathogens, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae using the agar diffusion and the broth dilution techniques. Ethanolic extracts of the plant parts showed activity against all the bacterial pathogens tested. At the highest extract concentration (200 mg/ml, the leaf extract exhibited the highest antimicrobial activity, while no activity was detected at the lowest concentration (3.13 mg/ml against the tested isolates. Escherichia coli and Staphylococcus aureus were more susceptible to all extracts of V. paradoxa, while Klebsiella pneumoniae showed the least sensitivity. The efficacy of ethanolic extracts of Vitellaria paradoxa was compared to a commercial antibiotic streptomycin. There were differences in the minimum inhibitory concentration (MIC of all the Vitellaria paradoxa ethanolic extracts with respect to the type of organism. All extracts exhibited bacteriostatic effects against the tested organisms at the experimented concentrations. Qualitative phytochemical screening of the extracts revealed the presence of saponins, tannins and alkaloids as the active principles of Vitellaria paradoxa's antimicrobial activity. V. paradoxa could be used as a potential source of antibiotic substance for a drug development.

  7. Antibacterial activity of the essential oil of Origanum vulgare L. (Lamiaceae against bacterial multiresistant strains isolated from nosocomial patients

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    Adalberto Coelho da Costa

    Full Text Available Antibiotics are considered the main therapeutic option to treat bacterial infections; however, there is the disadvantage of increasing bacterial resistance. Thus, the research of antimicrobials of plant origin has been an important alternative. This work aimed at determining the in vitro antibacterial activity of the essential oil of Origanum vulgare L. (Lamiaceae on multiresistant bacteria isolated from biological materials. 24 strains of nosocomial bacteria were used and divided into six different species that were inhibited by the essential oil in the preliminary "screening" which was accomplished by the diffusion technique in agar. MIC was determined by the microdilution method, beginning with solutions with the final concentrations: 8 up to 0.125% with the following results: The four samples (100% of Escherichia coli, Enterococcus faecalis and MRSA were inhibited by the essential oil at the concentration of 0.125%. Three samples (75% of Acinetobacter baumannii at 0.125% and a sample (25% at 0.5%; Klebsiella pneumoniae (75% at 0.125% and 25% at 0.25%; Pseudomonas aeruginosa (75% at 0.5% and 25% at 0.25%. MIC varied from 78 to 83%. It was concluded through the obtained data that there was not difference in the minimum bactericidal concentration (0.5% of the referred oil for Gram positive as well for Gram negative microorganisms.

  8. Aerobic De-Epoxydation of Trichothecene Mycotoxins by a Soil Bacterial Consortium Isolated Using In Situ Soil Enrichment

    Directory of Open Access Journals (Sweden)

    Wei-Jie He

    2016-09-01

    Full Text Available Globally, the trichothecene mycotoxins deoxynivalenol (DON and nivalenol (NIV are among the most widely distributed mycotoxins that contaminate small grain cereals. In this study, a bacterial consortium, PGC-3, with de-epoxydation activity was isolated from soil by an in situ soil enrichment method. Screening of 14 soil samples that were sprayed with DON revealed that 4 samples were able to biotransform DON into de-epoxydized DON (dE-DON. Among these, the PGC-3 consortium showed the highest and most stable activity to biotransform DON into dE-DON and NIV into dE-NIV. PGC-3 exhibited de-epoxydation activity at a wide range of pH (5–10 and temperatures (20–37 °C values under aerobic conditions. Sequential subculturing with a continued exposure to DON substantially reduced the microbial population diversity of this consortium. Analyses of the 16S rDNA sequences indicated that PGC-3 comprised 10 bacterial genera. Among these, one species, Desulfitobacterium, showed a steady increase in relative abundance, from 0.03% to 1.55% (a 52-fold increase, as higher concentrations of DON were used in the subculture media, from 0 to 500 μg/mL. This study establishes the foundation to further develop bioactive agents that can detoxify trichothecene mycotoxins in cereals and enables for the characterization of detoxifying genes and their regulation.

  9. Invasive bacterial disease trends and characterization of group B streptococcal isolates among young infants in southern Mozambique, 2001-2015.

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    Betuel Sigaúque

    Full Text Available Maternal group B streptococcal (GBS vaccines under development hold promise to prevent GBS disease in young infants. Sub-Saharan Africa has the highest estimated disease burden, although data on incidence and circulating strains are limited. We described invasive bacterial disease (IBD trends among infants <90 days in rural Mozambique during 2001-2015, with a focus on GBS epidemiology and strain characteristics.Community-level birth and mortality data were obtained from Manhiça's demographic surveillance system. IBD cases were captured through ongoing surveillance at Manhiça district hospital. Stored GBS isolates from cases underwent serotyping by multiplex PCR, antimicrobial susceptibility testing, and whole genome sequencing.There were 437 IBD cases, including 57 GBS cases. Significant declines in overall IBD, neonatal mortality, and stillbirth rates were observed (P<0.0001, but not for GBS (P = 0.17. In 2015, GBS was the leading cause of young infant IBD (2.7 per 1,000 live births. Among 35 GBS isolates available for testing, 31 (88.6% were highly related serotype III isolates within multilocus sequence types (STs 17 (68.6% or 109 (20.0%. All seven ST109 isolates (21.9% had elevated minimum inhibitory concentration (MIC to penicillin (≥0.12 μg/mL associated with penicillin-binding protein (PBP 2x substitution G398A. Epidemiologic and molecular data suggest this is a well-established clone.A notable young infant GBS disease burden persisted despite improvements in overall maternal and neonatal health. We report an established strain with pbp2x point mutation, a first-step mutation associated with reduced penicillin susceptibility within a well-known virulent lineage in rural Mozambique. Our findings further underscores the need for non-antibiotic GBS prevention strategies.

  10. In vitro activity of tigecycline, a new glycylcycline, tested against 1,326 clinical bacterial strains isolated from Latin America

    Directory of Open Access Journals (Sweden)

    Ana C. Gales

    Full Text Available The in vitro activity of tigecycline (former GAR-936, a new semisynthetic tetracycline, was evaluated in comparison with tetracycline and other antimicrobial agents. MATERIAL AND METHODS: A total of 1,326 contemporary clinical isolates collected from the Latin American region were collected in 2000-2002 period and tested with microdilution broth according to the CLSI guidelines. The bacterial pathogens evaluated included Staphylococcus aureus (505, Streptococcus pneumoniae (269, coagulase-negative staphylococci (CoNS; 227, Haemophilus influenzae (129, Enterococcus spp. (80, Moraxella catarrhalis (54, beta-haemolytic streptococci (28, viridans group streptococci (26, and Neisseria meningitidis (8 RESULTS:Tigecycline demonstrated excellent activity against all Gram-positive cocci, with 90% of penicillin-resistant S. pneumoniae strains being inhibited at 0.12 µg/mL, while the same isolates had an MIC90 of > 16 µg/mL for tetracycline. All Enterococcus spp. were inhibited at 0.25 µg/mL of tigecycline. Tigecycline (MIC50, 0.25 µg/mL was eight-fold more potent than minocycline (MIC50, 2 µg/mL against oxacillin-resistant S. aureus (ORSA; all ORSA were inhibited at < 2 µg/mL of tigecycline. Tigecycline demonstrated excellent activity (MIC50, 0.5 µg/mL against CoNS with reduced susceptibility to teicoplanin (MIC, 16 µg/mL. Tigecycline also showed high potency against respiratory pathogens such as M. catarrhalis (MIC50, 0.12 µg/mL and H. influenzae (MIC50, 0.5 µg/mL. No tigecycline resistant isolates were detected when the proposed susceptible breakpoints (< 4 µg/mL was applied. CONCLUSIONS: This results indicate that tigecycline has potent in vitro activity against clinically important pathogenic bacteria, including Gram-positive isolates resistant to both tetracycline and minocycline.

  11. Lactic Acid Bacterial Starter Culture with Antioxidant and γ-Aminobutyric Acid Biosynthetic Activities Isolated from Flatfish-Sikhae Fermentation.

    Science.gov (United States)

    Won, Yeong Geol; Yu, Hyun-Hee; Chang, Young-Hyo; Hwang, Han-Joon

    2015-12-01

    The aim of this study is to select a lactic acid bacterial strain as a starter culture for flatfish-Sikhae fermentation and to evaluate its suitability for application in a food system. Four strains of lactic acid bacteria isolated from commercial flatfish-Sikhae were identified and selected as starter culture candidates through investigation of growth rates, salt tolerance, food safety, and functional properties such as antioxidative and antimicrobial activities. The fermentation properties of the starter candidates were also examined in food systems prepared with these strains (candidate batch) in comparison with a spontaneous fermentation process without starter culture (control batch) at 15°C. The results showed that the candidate YG331 batch had better fermentation properties such as viable cell count, pH, and acidity than the other experimental batches, including the control batch. The results are expressed according to selection criteria based on a preliminary sensory evaluation and physiochemical investigation. Also, only a small amount of histamine was detected with the candidate YG331 batch. The radical scavenging activity of the candidate batches was better compared with the control batch, and especially candidate YG331 batch showed the best radical scavenging activity. Also, we isolated another starter candidate (identified as Lactobacillus brevis PM03) with γ-aminobutyric acid (GABA)-producing activity from commercial flatfish-Sikhae products. The sensory scores of the candidate YG331 batch were better than those of the other experimental batches in terms of flavor, color, and overall acceptance. In this study, we established selection criteria for the lactic acid bacterial starter for the flatfish-Sikhae production and finally selected candidate YG331 as the most suitable starter.

  12. Optimization of rhamnolipid production by biodegrading bacterial isolates using Plackett-Burman design.

    Science.gov (United States)

    Hassan, Mariam; Essam, Tamer; Yassin, Aymen S; Salama, Aisha

    2016-01-01

    Biosurfactants are biological surfactants produced by microorganisms. Pseudomonas species are well known for the production of the rhamnolipid biosurfactant. In this work, the production of rhamnolipid biosurfactant by Pseudomonas spp. was investigated and further optimized. Two Plackett-Burman designs to study the effect of carbon source, nitrogen source, C/N ratio, iron concentration, magnesium concentration, phenol toxicity, pH, temperature, agitation and sampling time were tested. The first design revealed an optimization that increased biosurfactant productivity by almost two to fivefolds for the tested isolates. However, using the second design showed no remarkable increase in biosurfactant productivity. An additional validation run was adopted using the predicted optimal medium with predicted optimal conditions. The validation run showed remarkable increase in the productivity of the tested isolates. The use of microorganisms with biodegradation ability coupled with optimization of the parameters affecting productivity provides an efficient strategy for biosurfactant production. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Antimicrobial activity of endophytic bacterial populations isolated from medical plants of Iran

    OpenAIRE

    Beiranvand, Maryam; Amin, Mansour; Hashemi-Shahraki, Abdolrazag; Romani, Bizhan; Yaghoubi, Sajad; Sadeghi, Parisa

    2017-01-01

    Background and Objectives: Endophytic actinobacteria colonize inside the plant tissues without causing damages to the host plant. Since these microorganisms colonize in the different parts of plants and can stop plant disease, they have been applied as biological agents for controlling human diseases. The aim of this study was molecular identification and measuring the antimicrobial activity of endophytic Actinomycetes isolated from medicinal plants of Iran. Materials and Methods: The total o...

  14. Optimization of isolation and cultivation of bacterial endophytes through addition of plant extract to nutrient media.

    Science.gov (United States)

    Eevers, N; Gielen, M; Sánchez-López, A; Jaspers, S; White, J C; Vangronsveld, J; Weyens, N

    2015-07-01

    Many endophytes have beneficial effects on plants and can be exploited in biotechnological applications. Studies hypothesize that only 0.001-1% of all plant-associated bacteria are cultivable. Moreover, even after successful isolations, many endophytic bacteria often show reduced regrowth capacity. This research aimed to optimize isolation processes and culturing these bacteria afterwards. We compared several minimal and complex media in a screening. Beside the media themselves, two gelling agents and adding plant extract to media were investigated to enhance the number and diversity of endophytes as well as the growth capacity when regrown after isolation. In this work, 869 medium delivered the highest numbers of cultivable bacteria, as well as the highest diversity. When comparing gelling agents, no differences were observed in the numbers of bacteria. Adding plant extract to the media lead to a slight increase in diversity. However, when adding plant extract to improve the regrowth capacity, sharp increases of viable bacteria occurred in both rich and minimal media. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  15. Multiple antibiotics resistant among environmental isolates of ...

    African Journals Online (AJOL)

    In this study we assessed the functionality of integrons, melanin-like pigment and biofilm formation on multidrug resistance among environmental isolates of Stenotrophomonas maltophilia. Marked resistances were noted against aztreonam (60%), cefepime (68%), ceftazidime (77%), ciprofloxacin (72%), gentamicin (65%), ...

  16. Optimization of medium components and physicochemical parameters to simultaneously enhance microbial growth and production of lypolitic enzymes by Stenotrophomonas sp.

    Science.gov (United States)

    Mazzucotelli, Cintia Anabela; Agüero, María Victoria; Del Rosario Moreira, María; Ansorena, María Roberta

    2016-05-01

    The optimization of lipase and esterase production (LP and EP) and bacterial growth (BG) of a Stenotrophomonas sp. strain was developed. For this purpose, the effect of five different medium components and three physicochemical parameters were evaluated using a Plackett-Burman statistical design. Among eight variables, stirring speed, pH, and peptone concentration were found to be the most effective factors on the three responses under evaluation. An optimization study applying Box-Behnken response surface methodology was used to study the interactive effects of the three selected variables on LP/EP and microorganism growth. Predicted models were found to be significant with high regression coefficients (90%-99%). By using the desirability function approach, the optimum condition applying simultaneous optimization of the three responses under study resulted to be: stirring speed of 100 rpm, pH of 7.5, and a peptone concentration of 10 g/L, with a desirability value of 0.977. Under these optimal conditions, it is possible to achieve in the optimized medium a 15-fold increase in esterase productivity, a 117-fold increase in lipase production, and a 9-log CFU/mL increase in BG, compared with the basal medium without agitation. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  17. Simultaneous hydrolysis of carbaryl and chlorpyrifos by Stenotrophomonas sp. strain YC-1 with surface-displayed carbaryl hydrolase.

    Science.gov (United States)

    Yang, Chao; Xu, Xiaoqing; Liu, Yanping; Jiang, Hong; Wu, Yunbo; Xu, Ping; Liu, Ruihua

    2017-10-17

    Many sites are often co-contaminated with multiple pesticides. To date, there are no reports on simultaneous degradation of different classes of pesticides by a natural microorganism. In this work, we aim at constructing a live biocatalyst able to simultaneously hydrolyze carbaryl and chlorpyrifos. For this purpose, carbaryl hydrolase (CH) was displayed on the cell surface of a chlorpyrifos-degrading bacterium Stenotrophomonas sp. strain YC-1 using N- and C-terminal domain of ice nucleation protein (INPNC) from Pseudomonas syringae INA5 as an anchoring motif. The localization of INPNC-CH fusion protein in the outer membrane fraction was demonstrated by cell fractionation followed by Western blot analysis. Surface display of INPNC-CH was further confirmed by proteinase accessibility experiment and immunofluorescence microscope. CH was present in an active form on cell surface without causing any growth inhibition, suggesting that the INP-based display system is a useful tool for surface expression of macromolecular heterologous proteins on the bacterial cell surface. Because surface-displayed CH has free access to pesticides, this bacterium can be used as a whole-cell biocatalyst for efficient hydrolysis of pesticides.

  18. Friends or foes: can we make a distinction between beneficial and harmful strains of the Stenotrophomonas maltophilia complex?

    Science.gov (United States)

    Berg, Gabriele; Martinez, Jose L

    2015-01-01

    Stenotrophomonas maltophilia is an emerging multi-drug-resistant global opportunistic pathogen of environmental, mainly plant-associated origin. It is also used as a biocontrol or stress protecting agent for crops in sustainable agricultural as well as in bioremediation strategies. In order to establish effective protocols to distinguish harmless from harmful strains, our discussion must take into consideration the current data available surrounding the ecology, evolution and pathogenicity of the species complex. The mutation rate was identified as one of several possible criteria for strain plasticity, but it is currently impossible to distinguish beneficial from harmful S. maltophilia strains. This may compromise the possibility of the release and application for environmental biotechnology of this bacterial species. The close relative S. rhizophila, which can be clearly differentiated from S. maltophilia, provides a harmless alternative for biotechnological applications without human health risks. This is mainly because it is unable to growth at the human body temperature, 37(∘)C due to the absence of heat shock genes and a potentially temperature-regulated suicide mechanism.

  19. Imported human brucellosis in Belgium: Bio and molecular typing of bacterial isolates, 1996-2015

    Science.gov (United States)

    Hanot Mambres, Delphine; Boarbi, Samira; Michel, Patrick; Bouker, Nora; Escobar-Calle, Luisa; Desqueper, Damien; Fancello, Tiziano; Van Esbroeck, Marjan; Godfroid, Jacques; Fretin, David

    2017-01-01

    Objectives The aim of this study was to characterize by classical biotyping and Multi-Locus variable number tandem repeats (VNTR) Analysis (MLVA) all Brucella spp. derived from human cases in Belgium from 1996 to 2015. Final goals were to determine the species and biovar, to trace-back on genetic grounds the origin of each strain when patient history and risk factors were missing, and to survey for particular trends at the national level. Methods A total of 37 Brucella strains, isolated from 37 patients in Belgium, were analyzed by both classical biotyping and MLVA, and the genetic patterns compared to those of human strains isolated worldwide. Results Classical biotyping revealed that isolates were mainly Brucella melitensis. Most of them belonged to biovar 3, the most abundant biovar in the Mediterranean region. MLVA confirmed that Brucella melitensis is too diverse in VNTRs to be able to make clusters associated to each biovar, but it allowed retrieving precious epidemiological information. The analysis highlighted the imported nature of the strains from all over the world with a dominant part from the Mediterranean countries. Findings of the MLVA11 testing were in line with the travel history of patients coming from Italy, Turkey, Lebanon and Peru. The analysis was particularly useful because it suggested the geographical origin of the infection for 12/16 patients for whom no case history was available. Conclusion Classical biotyping and MLVA analysis are not exclusive but remain complementary tools for Brucella melitensis strain surveillance. MLVA11 is sufficient for Brucella-free countries such as Belgium to trace the geographical origin of infection, but complete MLVA16 is needed to search for links with endemic areas. PMID:28384245

  20. [Streptococci isolated from the blood after tooth extraction. Their role in subacute bacterial endocarditis].

    Science.gov (United States)

    Hatzifotiadis, D; Tsamis, J; Szpirglas, H; Tsitini-Tsamis, M; Roth-Ghanassia, V

    1977-01-01

    A classification, according to the Lancefield's method, of the streptocoques isolated in the blood, after teeth extractions, as well as a determination of their sensibility to the antibiotics, are attempted in this study. It concerns to 23 adults, well supported, to whom multiple extractions, under general anesthesia have been done. We studied both biochemical and serological reactions, and a test for the antibiotic resistance is realised. We insiste in the contrindiction of streptomycine and sulfanilamides in the treatment or the prevention of bacteremia of dental origine.

  1. Bacillus niameyensis sp. nov., a new bacterial species isolated from human gut

    Directory of Open Access Journals (Sweden)

    M. Tidjani Alou

    2015-11-01

    Full Text Available Bacillus niameyensis sp. nov. strain SIT3T (= CSUR P1266 = DSM 29725 is the type strain of B. niameyensis sp. nov. This Gram-positive strain was isolated from the digestive flora of a child with kwashiorkor and is a facultative anaerobic rod and a member of the Bacillaceae family. This organism is hereby described alongside its complete genome sequence and annotation. The 4  286  116 bp long genome (one chromosome but no plasmid contains 4130 protein-coding and 66 RNA genes including five rRNA genes.

  2. Comparison of Lactobacillus crispatus isolates from Lactobacillus-dominated vaginal microbiomes with isolates from microbiomes containing bacterial vaginosis-associated bacteria.

    Science.gov (United States)

    Abdelmaksoud, Abdallah A; Koparde, Vishal N; Sheth, Nihar U; Serrano, Myrna G; Glascock, Abigail L; Fettweis, Jennifer M; Strauss, Jerome F; Buck, Gregory A; Jefferson, Kimberly K

    2016-03-01

    Vaginal lactobacilli can inhibit colonization by and growth of other bacteria, thereby preventing development of bacterial vaginosis (BV). Amongst the lactobacilli, Lactobacillus crispatus appears to be particularly effective at inhibiting growth of BV-associated bacteria. Nonetheless, some women who are colonized with this species can still develop clinical BV. Therefore, we sought to determine whether strains of L. crispatus that colonize women with lactobacilli-dominated vaginal microbiomes are distinct from strains that colonize women who develop BV. The genomes of L. crispatus isolates from four women with lactobacilli-dominated vaginal microbiomes ( Lactobacillus) and four women with microbiomes containing BV-associated bacteria (>12% 16S rRNA reads from bacterial taxa associated with BV) were sequenced and compared. Lactic acid production by the different strains was quantified. Phage induction in the strains was also analysed. There was considerable genetic diversity between strains, and several genes were exclusive to either the strains from Lactobacillus-dominated microbiomes or those containing BV-associated bacteria. Overall, strains from microbiomes dominated by lactobacilli did not differ from strains from microbiomes containing BV-associated bacteria with respect to lactic acid production. All of the strains contained multiple phage, but there was no clear distinction between the presence or absence of BV-associated bacteria with respect to phage-induced lysis. Genes found to be exclusive to the Lactobacillus-dominated versus BV-associated bacteria-containing microbiomes could play a role in the maintenance of vaginal health and the development of BV, respectively.

  3. Isolation and characterization of polymeric galloyl-ester-degrading bacteria from a tannery discharge place.

    Science.gov (United States)

    Franco, A R; Calheiros, C S C; Pacheco, C C; De Marco, P; Manaia, C M; Castro, P M L

    2005-11-01

    The culturable bacteria colonizing the rhizosphere of plants growing in the area of discharge of a tannery effluent were characterized. Relative proportions of aerobic, denitrifying, and sulfate-reducing bacteria were determined in the rhizosphere of Typha latifolia, Canna indica, and Phragmites australis. Aerobic bacteria were observed to be the most abundant group in the rhizosphere, and plant type did not seem to influence the abundance of the bacterial types analyzed. To isolate bacteria able to degrade polyphenols used in the tannery industry, enrichments were conducted under different conditions. Bacterial cultures were enriched with individual polyphenols (tannins Tara, Quebracho, or Mimosa) or with an undefined mixture of tannins present in the tannery effluent as carbon source. Cultures enriched with the effluent or Tara tannin were able to degrade tannic acid. Six bacterial isolates purified from these mixed cultures were able to use tannic acid as a sole carbon source in axenic culture. On the basis of 16S ribosomal DNA sequence analysis, these isolates were closely related to organisms belonging to the taxa Serratia, Stenotrophomonas maltophilia, Klebsiella oxytoca, Herbaspirillum chlorophenolicum, and Pseudomonas putida.

  4. Biodegradation of complex hydrocarbons in spent engine oil by novel bacterial consortium isolated from deep sea sediment.

    Science.gov (United States)

    Ganesh Kumar, A; Vijayakumar, Lakshmi; Joshi, Gajendra; Magesh Peter, D; Dharani, G; Kirubagaran, R

    2014-10-01

    Complex hydrocarbon and aromatic compounds degrading marine bacterial strains were isolated from deep sea sediment after enrichment on spent engine (SE) oil. Phenotypic characterization and phylogenetic analysis of 16S rRNA gene sequences showed the isolates were related to members of the Pseudoalteromonas sp., Ruegeria sp., Exiguobacterium sp. and Acinetobacter sp. Biodegradation using 1% (v/v) SE oil with individual and mixed strains showed the efficacy of SE oil utilization within a short retention time. The addition of non-ionic surfactant 0.05% (v/v) Tween 80 as emulsifying agent enhanced the solubility of hydrocarbons and renders them more accessible for biodegradation. The degradation of several compounds and the metabolites formed during the microbial oxidation process were confirmed by Fourier transform infrared spectroscopy and Gas chromatography-mass spectrometry analyses. The potential of this consortium to biodegrade SE oil with and without emulsifying agent provides possible application in bioremediation of oil contaminated marine environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Phenotypic and molecular characterization of bacterial populations isolated from diesel-contaminated soil and treated by two bioremediation technologies

    International Nuclear Information System (INIS)

    Arrieta R, Olga M; Rivera R, Angela P; Rojano, Benjamin; Ruiz, Orlando; Correa, Margarita M; Cienfuegos Gallet, Astrid V; Arias, Lida; Cardona G, Santiago A

    2012-01-01

    In this study bioremediation is presented as an alternative for the recovery of contaminated ecosystems. In this work an experimental diesel spill on pasture land was remediated using two bioremediation technologies: natural attenuation, which is the natural capability of indigenous microorganisms to degrade a xenobiotic component in a determined time, and biostimulation, which consist in the acceleration of the degradation process through the stimulation of the metabolism of indigenous microorganisms by the addition of nutrients (P and N) to the media. Results of respirometry assays indicated that both treatments produced significant levels of hydrocarbon removal but the biostimulation treatment stranded out with 98.17% degradation. Seven bacterial isolates were obtained from these treatments which according to their molecular characterization and phylogenetic analysis belong to the genus: Enterobacter, Bacillus, Arthrobacter, Sanguibacter, Staphylococcus and Flavobacterium. All isolates were able to metabolize diesel as a carbon and energy source; for this reason and taking into account that for some of these microorganisms their role in bioremediation have not been extensively studied, it is recommended to continue with their evaluation to know their real potential for the solution of environmental problems.

  6. Pseudomonas granadensis sp. nov., a new bacterial species isolated from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain.

    Science.gov (United States)

    Pascual, Javier; García-López, Marina; Bills, Gerald F; Genilloud, Olga

    2015-02-01

    During the course of screening bacterial isolates as sources of as-yet unknown bioactive compounds with pharmaceutical applications, a chemo-organotrophic, Gram-negative bacterium was isolated from a soil sample taken from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain. Strain F-278,770(T) was oxidase- and catalase-positive, aerobic, with a respiratory type of metabolism with oxygen as the terminal electron acceptor, non-spore-forming and motile by one polar flagellum, although some cells had two polar flagella. Phylogenetic analysis of the 16S rRNA, gyrB, rpoB and rpoD genes revealed that strain F-278,770(T) belongs to the Pseudomonas koreensis subgroup (Pseudomonas fluorescens lineage), with Pseudomonas moraviensis, P. koreensis, P. baetica and P. helmanticensis as its closest relatives. Chemotaxonomic traits such as polar lipid and fatty acid compositions and G+C content of genomic DNA corroborated the placement of strain F-278,770(T) in the genus Pseudomonas. DNA-DNA hybridization assays and phenotypic traits confirmed that this strain represents a novel species of the genus Pseudomonas, for which the name Pseudomonas granadensis sp. nov. is proposed. The type strain is F-278,770(T) ( = DSM 28040(T) = LMG 27940(T)). © 2015 Fundacion MEDINA, Centro de Excelencia en Investigacion de Medicamentos Innovadores en Andalucia.

  7. Potency of fiber rumen bacterial isolates from local buffalo inoculated into Frisian Holstein calves during preweaning period

    Directory of Open Access Journals (Sweden)

    Iwan Prihantoro

    2012-12-01

    Full Text Available Fiber-digesting bacteria are the main rumen bacteria that play an important role in digesting feed. These bacteria are adapted to low quality forage from agricultural byproduct. The aim of these study was to determine the potency of fiber-digesting bacteria consortium obtained from buffalo rumen inoculated to Frisian Holstein calves during preweaning on feed consumption, utilization, mineral uptake and physiological status. This study used 14 isolates of bacteria obtained from collection of Faculty of Animal Science, Bogor Agricultural University. The experimental unit consisted of six Frisian Holstein calves at two week old with the average body weight of 38.00 ± 6.23 kg. Calves were inoculated by 20 ml of fiber-digesting rumen bacterial isolates [4.56 x 109 cfu/ml] every morning for four weeks. Experimental design used was based on a completly randomized design with three calves received the respective inoculation (treatment group and three calves without any inoculation (control group. Data were analyzed statistically using t-test method with α = 0.05 and 0.01. The results showed that fiber-digesting bacteria (FDB from rumen buffalo have adapted in the calves rumen since preweaning periode. Inoculation FDB increased the number of rumen bacteria, digestibility of protein and P uptake calves at eight weeks old. Increased feed intake, uptake of Mg and cobalt calves at 14 weeks old. Without causing any negative effects on ADG, physiological status and rumen fermentability.

  8. Antimicrobial Evaluation of Bacterial Isolates from Urine Specimen of Patients with Complaints of Urinary Tract Infections in Awka, Nigeria

    Directory of Open Access Journals (Sweden)

    Perpetua A. Ekwealor

    2016-01-01

    Full Text Available Urinary tract infections (UTIs account for one of the major reasons for most hospital visits and the determination of the antimicrobial susceptibility patterns of uropathogens will help to guide physicians on the best choice of antibiotics to recommend to affected patients. This study is designed to isolate, characterize, and determine the antimicrobial susceptibility patterns of the pathogens associated with UTI in Anambra State Teaching Hospital, Amaku, Anambra State, Nigeria. Clean catch urine samples of inpatient and outpatient cases of UTI were collected and bacteriologically analyzed using standard microbiological procedures. Antibiogram was done by the Kirby-Bauer disc diffusion method. The most prevalent isolates were S. aureus (28%, E. coli (24.6%, and S. saprophyticus (20%. The antibacterial activities of the tested agents were in the order of Augmentin < Ceftazidime < Cefuroxime < Cefixime < Gentamicin < Ofloxacin < Ciprofloxacin < Nitrofurantoin. It was found that all the organisms were susceptible in varying degrees to Nitrofurantoin, Ciprofloxacin, and Ofloxacin. It was also observed that all the bacterial species except Streptococcus spp. have a Multiple Antibiotic Resistance Index (MARI greater than 0.2. For empiric treatment of UTIs in Awka locality, Nitrofurantoin, Ciprofloxacin, and Ofloxacin are the first line of choice.

  9. Phosphogypsum biotransformation by aerobic bacterial flora and isolated Trichoderma asperellum from Tunisian storage piles

    Energy Technology Data Exchange (ETDEWEB)

    Jalali, Jihen [Research Unit “Coastal and Urban Environments” National Engineering School of Sfax, BP 1173, 3038 Sfax (Tunisia); Tunisian Chemical Group, M’Dhilla-Gafsa factory, B.P. 215, 2100 Gafsa (Tunisia); Magdich, Salwa; Jarboui, Raja [Research Unit “Coastal and Urban Environments” National Engineering School of Sfax, BP 1173, 3038 Sfax (Tunisia); Loungou, Mouna [Tunisian Chemical Group, M’Dhilla-Gafsa factory, B.P. 215, 2100 Gafsa (Tunisia); Ammar, Emna, E-mail: ammarenis@yahoo.fr [Research Unit “Coastal and Urban Environments” National Engineering School of Sfax, BP 1173, 3038 Sfax (Tunisia)

    2016-05-05

    Highlights: • The enrichment culture on PG enabled the development of microorganisms. • The isolated Trichoderma asperellum grew on PG concentration at 200 g L{sup −1}. • At 200 g L{sup −1} PG concentration, the experimented strain reduced COD by 52.32%. • Metals concentrations reduction reached a maximum of 73% for the zinc. • Trichoderma asperellum is an efficient microorganism for PG bioremediation. - Abstract: Aerobic microorganisms able to grow on phosphogypsum (PG), characterized by heavy metals accumulation and high acidity were investigated by enrichment cultures. The PG was used at different concentrations, varying from 20 to 200 g/L in the enrichment culture medium supplemented with compost and Tamarix roots. This treatment reduced COD and heavy metals PG concentration. An efficient isolated fungus, identified by molecular approach as Trichoderma asperellum, was able to grow on PG as the sole carbon and energy sources at the different experimented concentrations, and to increase the culture media pH of the different PG concentrations used to 8.13. This fact would be the result of alkaline compound released during the fungus PG solubilization. Besides, the heavy metals and COD removal exceeded 52% after 7 days culture. At 200 g/L PG concentration, the experimented strain was able to reduce COD by 52.32% and metals concentrations by 73% for zinc, 63.75% for iron and 50% for cadmium. This exhibited the T. asperellum efficiency for heavy metals accumulation and for phosphogypsum bioremediation.

  10. Diesel biodegradation capacities of indigenous bacterial species isolated from diesel contaminated soil.

    Science.gov (United States)

    Palanisamy, Nandhini; Ramya, Jayaprakash; Kumar, Srilakshman; Vasanthi, Ns; Chandran, Preethy; Khan, Sudheer

    2014-01-01

    Petroleum based products are the major source of energy for industries and daily life. Leaks and accidental spills occur regularly during the exploration, production, refining, transport, and storage of petroleum and petroleum products. In the present study we isolated the bacteria from diesel contaminated soil and screened them for diesel biodegradation capacity. One monoculture isolate identified by 16S rRNA gene sequence analysis to be Acinetobacter baumannii was further studied for diesel oil biodegradation. The effects of various culture parameters (pH, temperature, NaCl concentrations, initial hydrocarbon concentration, initial inoculum size, role of chemical surfactant, and role of carbon and nitrogen sources) on biodegradation of diesel oil were evaluated. Optimal diesel oil biodegradation by A. baumanii occurred at initial pH 7, 35°C and initial hydrocarbon concentration at 4%. The biodegradation products under optimal cultural conditions were analyzed by GC-MS. The present study suggests that A. baumannii can be used for effective degradation of diesel oil from industrial effluents contaminated with diesel oil.

  11. Phosphogypsum biotransformation by aerobic bacterial flora and isolated Trichoderma asperellum from Tunisian storage piles

    International Nuclear Information System (INIS)

    Jalali, Jihen; Magdich, Salwa; Jarboui, Raja; Loungou, Mouna; Ammar, Emna

    2016-01-01

    Highlights: • The enrichment culture on PG enabled the development of microorganisms. • The isolated Trichoderma asperellum grew on PG concentration at 200 g L −1 . • At 200 g L −1 PG concentration, the experimented strain reduced COD by 52.32%. • Metals concentrations reduction reached a maximum of 73% for the zinc. • Trichoderma asperellum is an efficient microorganism for PG bioremediation. - Abstract: Aerobic microorganisms able to grow on phosphogypsum (PG), characterized by heavy metals accumulation and high acidity were investigated by enrichment cultures. The PG was used at different concentrations, varying from 20 to 200 g/L in the enrichment culture medium supplemented with compost and Tamarix roots. This treatment reduced COD and heavy metals PG concentration. An efficient isolated fungus, identified by molecular approach as Trichoderma asperellum, was able to grow on PG as the sole carbon and energy sources at the different experimented concentrations, and to increase the culture media pH of the different PG concentrations used to 8.13. This fact would be the result of alkaline compound released during the fungus PG solubilization. Besides, the heavy metals and COD removal exceeded 52% after 7 days culture. At 200 g/L PG concentration, the experimented strain was able to reduce COD by 52.32% and metals concentrations by 73% for zinc, 63.75% for iron and 50% for cadmium. This exhibited the T. asperellum efficiency for heavy metals accumulation and for phosphogypsum bioremediation.

  12. Isolation, taxonomic analysis, and phenotypic characterization of bacterial endophytes present in alfalfa (Medicago sativa) seeds.

    Science.gov (United States)

    López, José Luis; Alvarez, Florencia; Príncipe, Analía; Salas, María Eugenia; Lozano, Mauricio Javier; Draghi, Walter Omar; Jofré, Edgardo; Lagares, Antonio

    2018-02-10

    A growing body of evidence has reinforced the central role of microbiomes in the life of sound multicellular eukaryotes, thus more properly described as true holobionts. Though soil was considered a main source of plant microbiomes, seeds have been shown to be endophytically colonized by microorganisms thus representing natural carriers of a selected microbial inoculum to the young seedlings. In this work we have investigated the type of culturable endophytic bacteria that are carried within surface-sterilized alfalfa seeds. MALDI-TOF analysis revealed the presence of bacteria that belonged to 40 separate genera, distributed within four taxa (Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes). Nonsymbiotic members of the Rhizobiaceae family were also found. The evaluation of nine different in-vitro biochemical activities demonstrated isolates with complex combinations of traits that, upon a Principal-Component-Analysis, could be classified into four phenotypic groups. That isolates from nearly half of the genera identified had been able to colonize alfalfa plants grown under axenic conditions was remarkable. Further analyses should be addressed to investigating the colonization mechanisms of the alfalfa seeds, the evolutionary significance of the alfalfa-seed endophytes, and also how after germination the seed microbiome competes with spermospheric and rhizospheric soil bacteria to colonize newly emerging seedlings. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. The effects of daily chlorhexidine bathing on cutaneous bacterial isolates: a pilot study

    Directory of Open Access Journals (Sweden)

    Soma VL

    2012-04-01

    Full Text Available Vijaya L Soma1, Xuan Qin2, Chuan Zhou1, Amanda Adler1, Jessica E Berry2, Danielle M Zerr11Department of Pediatrics, 2Department of Laboratory Medicine, University of Washington, Seattle, WA, USAAbstract: Chlorhexidine gluconate (CHG is a topical antiseptic used in a myriad of clinical settings. Recently, CHG baths have been shown to decrease multidrug-resistant organism acquisition and infections and catheter-associated bloodstream infections. The present study examined the effects of daily bathing with CHG on the recovery and antimicrobial susceptibility of cultivable cutaneous bacteria. The objectives of this study were to (1 explore the effects of clinical CHG bathing on cultivable cutaneous bacteria, (2 study the relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility of coagulase-negative staphylococci, and (3 demonstrate the feasibility of the approach so a more definitive study may be performed. Significant decreases in bacterial colony counts and phenotypic diversity occurred with greater CHG exposure. The findings also suggest an inverse relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility. Larger prospective studies are necessary to fully investigate the clinical impact of CHG usage.Keywords: antiseptic, resistance, Staphylococcus, coagulase-negative

  14. Kocuria massiliensis sp. nov, a new bacterial species isolated from a patient with foot osteomyelitis.

    Science.gov (United States)

    Edouard, Sophie; Fournier, Pierre-Edouard; Beye, Mamadou; Gouriet, Frédérique; Dubourg, Gregory; Delerce, Jeremy; Swiader, Laure; Raoult, Didier

    2018-04-01

    Most of the species from the genus Kocuria are environmental or commensals of mammalian skin and oral bacteria, and had rarely been associated with human infection. However, recent reports showed an increase of the clinical role of these bacteria in human infectious diseases. Most of the cases occurred in hospitals and were device related. They included bacteremia, peritonitis, abscess, endocarditis and ocular infection. We here describe the main characteristics and the draft genome of Kocuria massiliensis sp. nov., strain P3598 T (CSURP3598), a new Kocuria species that caused foot osteomyelitis in a 78-year-old woman. The improvement of diagnostic tools for the identification of bacteria in microbiological laboratories, including MALDI-TOF MS and 16S rRNA sequencing, largely contributed to the emergence and to the expansion of the clinical spectrum of infections caused by Kocuria spp. To the best of our knowledge, we report here the first case of osteomyelitis with a bacterial species from the genus Kocuria.

  15. MicroRNA expression in lung tissue and blood isolated from pigs suffering from bacterial pneumonia

    DEFF Research Database (Denmark)

    Skovgaard, Kerstin; Wendt, Karin Tarp; Heegaard, Peter M. H.

    MicroRNAs (miRNAs) are a highly evolutionarily conserved group of small non-coding RNA molecules, which regulate the activity of other genes at the post-transcriptional level. Recently it has become evident that miRNA plays an important role in modulating and fine tuning of the innate and adaptive...... expressed (p-values lower than 0.05). MicroRNA expression in lung tissue over time in response to the two different serotypes were very similar. miR-223 was found to be highly up regulated, followed by miR-146a and to a lesser degree miR-21 in lung tissue of the AP serotype 2 infected animals. MiR-233...... immune responses. Still, little is known about the impact of miRNAs in the development and pathogenesis of lung infections. Expression of miRNA, known to be induced by bacterial (i.e., LPS) ligands and thus supposed to play a role in the regulation of antimicrobial defence, were studied in lung tissue...

  16. Bacterial microcompartments: widespread prokaryotic organelles for isolation and optimization of metabolic pathways.

    Science.gov (United States)

    Bobik, Thomas A; Lehman, Brent P; Yeates, Todd O

    2015-10-01

    Prokaryotes use subcellular compartments for a variety of purposes. An intriguing example is a family of complex subcellular organelles known as bacterial microcompartments (MCPs). MCPs are widely distributed among bacteria and impact processes ranging from global carbon fixation to enteric pathogenesis. Overall, MCPs consist of metabolic enzymes encased within a protein shell, and their function is to optimize biochemical pathways by confining toxic or volatile metabolic intermediates. MCPs are fundamentally different from other organelles in having a complex protein shell rather than a lipid-based membrane as an outer barrier. This unusual feature raises basic questions about organelle assembly, protein targeting and metabolite transport. In this review, we discuss the three best-studied MCPs highlighting atomic-level models for shell assembly, targeting sequences that direct enzyme encapsulation, multivalent proteins that organize the lumen enzymes, the principles of metabolite movement across the shell, internal cofactor recycling, a potential system of allosteric regulation of metabolite transport and the mechanism and rationale behind the functional diversification of the proteins that form the shell. We also touch on some potential biotechnology applications of an unusual compartment designed by nature to optimize metabolic processes within a cellular context. © 2015 John Wiley & Sons Ltd.

  17. Resistance patterns of bacterial isolates to antimicrobials from 3 hospitals in the United Arab Emirates

    International Nuclear Information System (INIS)

    AlDhaheri, Ahmed S; AlNiyadi, Mohammed S; AlDhaheri Ahmed D; Bastaki, Salim M

    2009-01-01

    To compare the resistance pattern of common bacterial pathogens to commonly used drugs. Information and statistics of antimicrobial resistance for 1994 and 2005 were collected from the 3 hospital microbiology laboratories in the United Arab Emirates. The resistance patterns of Staphylococcus aureus, Escherichia coli, Klebsiella spp, and Pseudomonas aeruginosa to several front-line drugs were estimated. All laboratories used automatic machines (Vitek 2), which identifies and determines minimum inhibitory concentrations simultaneously. Increased resistance was observed for Staphylococcus aureus, (n=315, 2005) to erythromycin (approximately 6 fold, Al-Ain Hospital only), cloxacillin (Al-Ain Hospital), and gentamicin (more than 3-10 folds in all hospitals). Increased penicillin resistance was not observed. For the common Gram-negative organisms, there was a high resistance to ampicillin, gentamicin, ceftriaxone, ciprofloxacin, and imipenem, which seemed to increase for Escherichia coli, (by 4.2-200%, n=305, 2005); however, there was very little resistance to imipenem (0.4%) in Tawam Hospital. Variable resistance patterns were obtained for Pseudomonas aeruginosa (n=316, 2005) and Klebsiella spp,(n=316, 2005) against aminoglycosides, cephalosporins, ciprofloxacin, and norfloxacin. Overall, there was an obvious increase in resistance of bacteria and the prevalence rate to a number of drugs from 1-120 folds during the 11-year period. (author)

  18. Bioremediation of petroleum based contaminants with biosurfactant produced by a newly isolated petroleum oil degrading bacterial strain

    Directory of Open Access Journals (Sweden)

    Debajit Borah

    2017-03-01

    Full Text Available Petroleum based hydrocarbon degrading and biosurfactant producing bacterial strain was isolated from an automobile engine. The strain was identified as Bacillus cereus DRDU1 on the basis of 16S rDNA sequencing analysis. The strain was found to be efficiently degrading 96% of kerosene making it a potential tool for bioremediation of petroleum based contaminants. Production and optimization of the biosurfactant produced by the isolate were also carried out. Surface hydrophobicity trait of isolate was found to be 60.67 ± 1.53% and foaming percentage of the crude biosurfactant was found to be 31.33 ± 0.58%. The presence of amino acids and sugar moieties in the biosurfactant was confirmed by biochemical tests and were further validated by FTIR (the Fourier transform infrared spectrometric analysis revealing the presence of υOH, υCOO, υCOOH, υCH (stretching, υNH, υCH2, υCH3, and υCH (bending, and υCO (ester in the surfactant. The decrease in contact angle of hydrocarbon oil from (30.67 ± 1.15° to (21.3 ± 1.53° respectively after 3 and 6 days of incubation reveals its potential to emulsify petroleum oil. Further, emulsification index (E24 of biosurfactant against kerosene, crude oil, and used engine oil were determined to be 55.33 ± 1.53%, 29.67 ± 1.53%, and 20 ± 1% respectively which attracts its future application in MEOR (microbial enhanced oil recovery process.

  19. “Streptomyces massilialgeriensis” sp. nov., a new bacterial species isolated from an extremely saline soil collected from the dry lake of Ank el Djamel in Algeria

    Directory of Open Access Journals (Sweden)

    C.E. Djaballah

    2018-01-01

    Full Text Available We report here the main characteristics of “Streptomyces massilialgeriensis” strain S35T (CSUR = P3927, a new bacterial species within the Streptomyces genus, isolated from an extremely saline soil sample collected from the site of Garaet Ank Djemel in the Wilaya of Oum El Bouaghi, Algeria.

  20. Characterization of novel extracellular protease produced by marine bacterial isolate from the Indian Ocean

    Directory of Open Access Journals (Sweden)

    Rachana Fulzele

    2011-12-01

    Full Text Available Out of the vast pool of enzymes, proteolytic enzymes from microorganisms are the most widely used in different industries such as detergent, food, peptide production etc. Several marine microorganisms are known to produce proteases with commercially desirable characteristics. We have isolated nine different cultures from marine samples of the Indian Ocean. All of them were i motile ii rod shaped iii non spore forming iv catalase and amylase positive v able to grow in presence of 10 % NaCl. They produced acid from glucose, fructose and maltose and grew optimally at 30 0C temperature and pH 7.0-8.0. None of them could grow above 45 0C and below 15 0C. Only one of them (MBRI 7 exhibited extracellular protease activity on skim milk agar plates. Based on 16S rDNA sequencing, it belonged to the genus Marinobacter (98% sequence similarity, 1201 bp. The cell free extract was used to study effects of temperature and pH on protease activity. The optimum temperature and pH for activity were found to be 40 0C and 7.0 respectively. The crude enzyme was stable at temperature range of 30-80 0C and pH 5.0-9.0. It retained 60 % activity at 80 0C after 4 h and more than 70 % activity at 70 0C after 1 h. D value was found to be 342 minutes and 78 minutes for 40 0C and 80 0C respectively. Interestingly the enzyme remained 50 % active at pH 9.0 after 1 h. Comparison with other proteases from different microbial sources indicated that the neutral protease from the halotolerant marine isolate MBRI 7 is a novel enzyme with high thermostability.

  1. SISPA-Seq for rapid whole genome surveys of bacterial isolates.

    Science.gov (United States)

    Wright, Meredith S; Stockwell, Timothy B; Beck, Erin; Busam, Dana A; Bajaksouzian, Saralee; Jacobs, Michael R; Bonomo, Robert A; Adams, Mark D

    2015-06-01

    Whole genome sequencing (WGS) of large isolate collections has many applications, yet sequencing costs are still significant. We sought to develop a rapid and cost efficient WGS method to address fundamental questions in clinical microbiology. We evaluated the performance of SISPA (Sequence-Independent, Single-Primer Amplification) combined with next-generation sequencing (SISPA-Seq) of 75 clinical isolates of Acinetobacter baumannii to establish whether SISPA-Seq resulted in sufficient coverage and quality to (1) determine strain phylogenetic placement and (2) and carriage of known antibiotic resistance (AbR) genes. Strains for which whole genome sequences were available were included for validation. Two libraries for each strain were constructed from separate SISPA reactions with different barcoded primers, using genomic DNA prepared from either high quality or rapid heat-lysis preparations. SISPA-Seq resulted in a median of 65× genome coverage when reads from both primer sets were combined. Coverage and quality were sufficient for detection of AbR genes by comparison of reads to the ARG-ANNOT database and were often sufficient to distinguish between different allelic variants of the same gene. kSNP and RAxML were used to construct a robust phylogeny based on single-nucleotide variants (SNVs) that showed that the SISPA-Seq data was sufficient for sensitive and accurate phylogenetic placement. Advantages of the SISPA-Seq method include inexpensive and rapid DNA preparation and a typical total cost less than one-half that of standard genome sequencing. In summary, SISPA-Seq can be used to survey whole genomes of a large strain collection and identify strains that should be targeted for additional sequencing. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Biocontrol of verticillium wilt and colonization of cotton plants by an endophytic bacterial isolate.

    Science.gov (United States)

    Li, C-H; Shi, L; Han, Q; Hu, H-L; Zhao, M-W; Tang, C-M; Li, S-P

    2012-09-01

    To explore biocontrol potential of 39 DAEB isolates (doubly antagonistic towards both Verticillium dahliae Kleb and Fusarium oxysporum) against verticillium wilt of cotton and to elucidate colonization and category characteristics of an endophytic bacterium with significant biocontrol activity. Thirty-nine antagonistic endophytic bacteria strains were tested for their ability to control verticillium wilt in cotton plants caused by a defoliating pathotype of V. dahliae 107 in cotton under controlled conditions. The biocontrol trial revealed that an endophytic bacterium, designated HA02, showed a significant biocontrol activity to V. dahliae 107. After cotton seedlings were inoculated with a gfp gene-tagged HA02 (HA02-gfp), HA02-gfp populations were higher in the root than in the stem; in addition, the HA02-gfp was distributed in the maturation zone of cotton root. Furthermore, HA02-gfp also colonized seedlings of maize, rape and soybean after the bacteria inoculation. Phylogenetic trees based on 16S rDNA sequences combined with morphological, physiological and identification showed that the bacterium belongs to the Enterobacter genus. Our results showed that only 1 of 39 DAEB isolates demonstrated more efficient biocontrol potential towards V. dahliae 107 in greenhouse and field trials. HA02-gfp mainly colonized cotton in roots. In addition, we quantitatively observed HA02 colonization in other hosts. HA02 belongs to the Enterobacter genus. This is the first study on biocontrol to defoliating pathotype of V. dahliae Kleb by endophytic bacteria. The HA02 showed effective biocontrol to V. dahliae 107 in greenhouse and field trials. Furthermore, we assessed the quantitative and qualitative colonization of HA02 in cotton seedlings. Our study provides basic information to further explore managing strategies to control this critical disease. © 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  3. Interaction of legionella pneumophila and helicobacter pylori with bacterial species isolated from drinking water biofilms

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    Azevedo Nuno F

    2011-03-01

    Full Text Available Abstract Background It is well established that Legionella pneumophila is a waterborne pathogen; by contrast, the mode of Helicobacter pylori transmission remains unknown but water seems to play an important role. This work aims to study the influence of five microorganisms isolated from drinking water biofilms on the survival and integration of both of these pathogens into biofilms. Results Firstly, both pathogens were studied for auto- and co-aggregation with the species isolated from drinking water; subsequently the formation of mono and dual-species biofilms by L. pneumophila or H. pylori with the same microorganisms was investigated. Neither auto- nor co-aggregation was observed between the microorganisms tested. For biofilm studies, sessile cells were quantified in terms of total cells by SYTO 9 staining, viable L. pneumophila or H. pylori cells were quantified using 16 S rRNA-specific peptide nucleic acid (PNA probes and cultivable cells by standard culture techniques. Acidovorax sp. and Sphingomonas sp. appeared to have an antagonistic effect on L. pneumophila cultivability but not on the viability (as assessed by rRNA content using the PNA probe, possibly leading to the formation of viable but noncultivable (VBNC cells, whereas Mycobacterium chelonae increased the cultivability of this pathogen. The results obtained for H. pylori showed that M. chelonae and Sphingomonas sp. help this pathogen to maintain cultivability for at least 24 hours. Conclusions It appears that M. chelonae may have an important role in the survival of both pathogens in drinking water. This work also suggests that the presence of some microorganisms can decrease the cultivability of L. pneumophila but not the viability which indicates that the presence of autochthonous microorganisms can lead to misleading results when the safety of water is assessed by cultivable methods alone.

  4. Detection of carboxylesterase and esterase activity in culturable gut bacterial flora isolated from diamondback moth, Plutella xylostella (Linnaeus, from India and its possible role in indoxacarb degradation

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    Shanivarsanthe Leelesh Ramya

    2016-06-01

    Full Text Available Abstract Diamondback moth (DBM, Plutella xylostella (Linnaeus, is a notorious pest of brassica crops worldwide and is resistant to all groups of insecticides. The insect system harbors diverse groups of microbiota, which in turn helps in enzymatic degradation of xenobiotic-like insecticides. The present study aimed to determine the diversity of gut microflora in DBM, quantify esterase activity and elucidate their possible role in degradation of indoxacarb. We screened 11 geographic populations of DBM in India and analyzed them for bacterial diversity. The culturable gut bacterial flora underwent molecular characterization with 16S rRNA. We obtained 25 bacterial isolates from larvae (n = 13 and adults (n = 12 of DBM. In larval gut isolates, gammaproteobacteria was the most abundant (76%, followed by bacilli (15.4%. Molecular characterization placed adult gut bacterial strains into three major classes based on abundance: gammaproteobacteria (66%, bacilli (16.7% and flavobacteria (16.7%. Esterase activity from 19 gut bacterial isolates ranged from 0.072 to 2.32 µmol/min/mg protein. Esterase bands were observed in 15 bacterial strains and the banding pattern differed in Bacillus cereus – KC985225 and Pantoea agglomerans – KC985229. The bands were characterized as carboxylesterase with profenofos used as an inhibitor. Minimal media study showed that B. cereus degraded indoxacarb up to 20%, so it could use indoxacarb for metabolism and growth. Furthermore, esterase activity was greater with minimal media than control media: 1.87 versus 0.26 µmol/min/mg protein. Apart from the insect esterases, bacterial carboxylesterase may aid in the degradation of insecticides in DBM.

  5. Study of Prevalence and Antimicrobial Susceptibility of Blood Culture Bacterial Isolates

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    Ayobola, E. D.

    2011-01-01

    Full Text Available Bloodstream infections are associated with significant morbidity and mortality. Definitive diagnosis is by bacteriologic culture of blood samples to identify organisms and establish antibiotic susceptibility. Between July and September 2009, 249 blood samples collected from patients at the University of Benin Teaching Hospital were processed. Positive cultures which accounted for 48(19.3% of total samples screened, were purified and identified according to standard methods. Sensitivity of bacteria to different antibiotics was determined by Kirby-Bauer disk diffusion method. Microorganisms recovered were Staphylococcus aureus (14.6%, Providencia spp., Pseudomonas aeruginosa, Enterobacter spp., Klebsiella pneumoniae and Proteus mirabilis (12.5% respectively, Escherichia coli and Staphylococcus epidermidis (8.3% respectively and Citrobacter freundii (6.3% . The highest antibiotic activities against Gram positive isolates were observed for ofloxacin (90.9%, nitrofurantoin (81.8% and gentamicin (72.7%, while in Gram negative bacteria, ofloxacin (81.1% and nalidixic acid (45.9% were most effective. The possibility of drug resistance acquisition by bacteria makes continuous surveillance of antimicrobial susceptibility patterns of bacteria essential as this will enhance efforts to identify resistance and attempt to limit its spread.

  6. Colonization and Maize Growth Promotion Induced by Phosphate Solubilizing Bacterial Isolates.

    Science.gov (United States)

    Li, Yongbin; Liu, Xiaomeng; Hao, Tianyi; Chen, Sanfeng

    2017-06-29

    Phosphorus (P) limits the production of maize, one of the major food crops in China. Phosphate-solubilizing bacteria (PSB) have the capacity to solubilize phosphate complexes into plant absorbable and utilizable forms by the process of acidification, chelation, and exchange reactions. In this study, six bacteria, including one Paenibacillus sp. B1 strain, four Pseudomonas sp. strains (B10, B14, SX1, and SX2) and one Sphingobium sp. SX14 strain, were those isolated from the maize rhizosphere and identified based on their 16S rRNA sequences. All strains could solubilize inorganic P (Ca₃(PO₄)₂, FePO₄ and AlPO₄), and only B1 and B10 organic P (lecithin). All strains, except of SX1, produced IAA, and SX14 and B1 showed the highest level. B1 incited the highest increase in root length and the second increase in shoot and total dry weight, shoot length, and total P and nitrogen (N), along with increased root length. In addition, by confocal laser scanning microscopy (CLSM), we found that green fluorescent protein (GFP)-labeled B1 mainly colonized root surfaces and in epidermal and cortical tissue. Importantly, B1 can survive through forming spores under adverse conditions and prolong quality guarantee period of bio-fertilizer. Therefore, it can act as a good substitute for bio-fertilizer to promote agricultural sustainability.

  7. The bacterial condensin MukB compacts DNA by sequestering supercoils and stabilizing topologically isolated loops.

    Science.gov (United States)

    Kumar, Rupesh; Grosbart, Małgorzata; Nurse, Pearl; Bahng, Soon; Wyman, Claire L; Marians, Kenneth J

    2017-10-13

    MukB is a structural maintenance of chromosome-like protein required for DNA condensation. The complete condensin is a large tripartite complex of MukB, the kleisin, MukF, and an accessory protein, MukE. As found previously, MukB DNA condensation is a stepwise process. We have defined these steps topologically. They proceed first via the formation of negative supercoils that are sequestered by the protein followed by hinge-hinge interactions between MukB dimers that stabilize topologically isolated loops in the DNA. MukB itself is sufficient to mediate both of these topological alterations; neither ATP nor MukEF is required. We show that the MukB hinge region binds DNA and that this region of the protein is involved in sequestration of supercoils. Cells carrying mutations in the MukB hinge that reduce DNA condensation in vitro exhibit nucleoid decondensation in vivo . © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. Marine Fungal and Bacterial Isolates for Lipase Production: A Comparative Study.

    Science.gov (United States)

    Patnala, H S; Kabilan, U; Gopalakrishnan, L; Rao, R M D; Kumar, D S

    Lipases, belonging to the class of enzymes called hydrolases, can catalyze triglycerides to fatty acids and glycerol. They are produced by microbes of plant and animal origin, and also by marine organisms. As marine microorganisms thrive in extreme conditions, lipases isolated from their origin possess characteristics of extremozymes, retain its activity in extreme conditions and can catalyze few chemical reactions which are impossible otherwise relative to the lipase produced from terrestrial microorganisms. Lipases are useful in many industries like detergent, food, leather, pharmaceutical, diary, etc. Few commercial enzymes have been developed and the use of them in certain industries like dairy, soaps are proved to be beneficial. There are few research papers reporting the production of lipase from marine bacteria and fungi. Lipase production involves two types of fermentation processes-solid-state fermentation (SSF) and submerged fermentation (SmF). Although SmF process is used conventionally, SSF process produces lipase in higher amounts. The production is also influenced by the composition of the medium, physiochemical parameters like temperature, pH, carbon, and nitrogen sources. © 2016 Elsevier Inc. All rights reserved.

  9. Phosphogypsum biotransformation by aerobic bacterial flora and isolated Trichoderma asperellum from Tunisian storage piles.

    Science.gov (United States)

    Jalali, Jihen; Magdich, Salwa; Jarboui, Raja; Loungou, Mouna; Ammar, Emna

    2016-05-05

    Aerobic microorganisms able to grow on phosphogypsum (PG), characterized by heavy metals accumulation and high acidity were investigated by enrichment cultures. The PG was used at different concentrations, varying from 20 to 200 g/L in the enrichment culture medium supplemented with compost and Tamarix roots. This treatment reduced COD and heavy metals PG concentration. An efficient isolated fungus, identified by molecular approach as Trichoderma asperellum, was able to grow on PG as the sole carbon and energy sources at the different experimented concentrations, and to increase the culture media pH of the different PG concentrations used to 8.13. This fact would be the result of alkaline compound released during the fungus PG solubilization. Besides, the heavy metals and COD removal exceeded 52% after 7 days culture. At 200 g/LPG concentration, the experimented strain was able to reduce COD by 52.32% and metals concentrations by 73% for zinc, 63.75% for iron and 50% for cadmium. This exhibited the T. asperellum efficiency for heavy metals accumulation and for phosphogypsum bioremediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Isolation and characterization of bacterial strains Paenibacillus sp. and Bacillus sp. for kraft lignin decolorization from pulp paper mill waste.

    Science.gov (United States)

    Chandra, Ram; Singh, Shail; Krishna Reddy, M M; Patel, D K; Purohit, Hemant J; Kapley, Atya

    2008-12-01

    Eight aerobic bacterial strains were isolated from pulp paper mill waste and screened for tolerance of kraft lignin (KL) using the nutrient enrichment technique in mineral salt media (MSM) agar plate (15 g/L) amended with different concentrations of KL (100, 200, 300, 400, 500, 600 ppm) along with 1% glucose and 0.5% peptone (w/v) as additional carbon and nitrogen sources. The strains ITRC S6 and ITRC S8 were found to have the most potential for tolerance of the highest concentration of KL. These organisms were characterized by biochemical tests and further 16S rRNA gene (rDNA) sequencing, which showed 96.5% and 95% sequence similarity of ITRC S(6) and ITRC S(8) and confirmed them as Paenibacillus sp. and Bacillus sp., respectively. KL decolorization was routinely monitored with a spectrophotometer and further confirmed by HPLC analysis. Among eight strains, ITRC S(6) and ITRC S(8) were found to degrade 500 mg/L of KL up to 47.97% and 65.58%, respectively, within 144 h of incubation in the presence of 1% glucose and 0.5% (w/v) peptone as a supplementary source of carbon and nitrogen. In the absence of glucose and peptone, these bacteria were unable to utilize KL. The analysis of lignin degradation products by GC-MS analysis revealed the formation of various acids as lignin monomers which resulted in a decrease in pH and a major change in the chromatographic profile of the bacterial degraded sample as compared to the control clear indications of biochemical modification of KL due to the bacterial ligninolytic system by ITRC S(6), namely, acetic acid, propanoic acid, butanoic acid, guaiacol, hexanoic acid, and ITRC S(8), namely acetic acid, propanoic acid, ethanedioic acid, furan carboxylic acid, 2-propanoic acid, butanoic acid, 3-acetoxybutyric acid, propanedioic acid, acetoguiacone, 1,2,3-thiadiazole, 5-carboxaldixime, 4-hydroxy-3,5-dimethoxyphenol, and dibutyl phthalate, indicating the bacterium characteristic to degrade G and S units of lignin polymer.

  11. Stenotrophomonas maltophilia: A Gram-Negative Bacterium Useful for Transformations of Flavanone and Chalcone

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    Edyta Kostrzewa-Susłow

    2017-10-01

    Full Text Available A group of flavones, isoflavones, flavanones, and chalcones was subjected to small-scale biotransformation studies with the Gram-negative Stenotrophomonas maltophilia KB2 strain in order to evaluate the capability of this strain to transform flavonoid compounds and to investigate the relationship between compound structure and transformation type. The tested strain transformed flavanones and chalcones. The main type of transformation of compounds with a flavanone moiety was central heterocyclic C ring cleavage, leading to chalcone and dihydrochalcone structures, whereas chalcones underwent reduction to dihydrochalcones and cyclisation to a benzo-γ-pyrone moiety. Substrates with a C-2–C-3 double bond (flavones and isoflavones were not transformed by Stenotrophomonas maltophilia KB2.

  12. Comparison of Asian porcine high fever disease isolates of porcine reproductive and respiratory syndrome virus to United States isolates for their ability to cause disease and secondary bacterial infection in swine

    Science.gov (United States)

    Epidemiologic data from Asian outbreaks of highly-pathogenic (HP) porcine reproductive and respiratory syndrome virus (PRRSV) suggest that disease severity was associated with both the virulence of the PRRSV isolates and secondary bacterial infections. Previous reports have indicated that U.S. isola...

  13. Complete genome sequence of the extremely acidophilic methanotroph isolate V4, Methylacidiphilum infernorum, a representative of the bacterial phylum Verrucomicrobia

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    Stott Matthew B

    2008-07-01

    Full Text Available Abstract Background The phylum Verrucomicrobia is a widespread but poorly characterized bacterial clade. Although cultivation-independent approaches detect representatives of this phylum in a wide range of environments, including soils, seawater, hot springs and human gastrointestinal tract, only few have been isolated in pure culture. We have recently reported cultivation and initial characterization of an extremely acidophilic methanotrophic member of the Verrucomicrobia, strain V4, isolated from the Hell's Gate geothermal area in New Zealand. Similar organisms were independently isolated from geothermal systems in Italy and Russia. Results We report the complete genome sequence of strain V4, the first one from a representative of the Verrucomicrobia. Isolate V4, initially named "Methylokorus infernorum" (and recently renamed Methylacidiphilum infernorum is an autotrophic bacterium with a streamlined genome of ~2.3 Mbp that encodes simple signal transduction pathways and has a limited potential for regulation of gene expression. Central metabolism of M. infernorum was reconstructed almost completely and revealed highly interconnected pathways of autotrophic central metabolism and modifications of C1-utilization pathways compared to other known methylotrophs. The M. infernorum genome does not encode tubulin, which was previously discovered in bacteria of the genus Prosthecobacter, or close homologs of any other signature eukaryotic proteins. Phylogenetic analysis of ribosomal proteins and RNA polymerase subunits unequivocally supports grouping Planctomycetes, Verrucomicrobia and Chlamydiae into a single clade, the PVC superphylum, despite dramatically different gene content in members of these three groups. Comparative-genomic analysis suggests that evolution of the M. infernorum lineage involved extensive horizontal gene exchange with a variety of bacteria. The genome of M. infernorum shows apparent adaptations for existence under extremely

  14. Control of Pseudomonas aeruginosa and Stenotrophomonas maltophilia contamination of microfiltered water dispensers with peracetic acid and hydrogen peroxide.

    Science.gov (United States)

    Sacchetti, Rossella; De Luca, Giovanna; Zanetti, Franca

    2009-06-30

    The abilities of peracetic acid and hydrogen peroxide to remove or reduce Pseudomonas aeruginosa and Stenotrophomonas maltophilia in output water from microfiltered water dispensers (MWDs) were investigated. Two MWDs were inoculated with strains of P. aeruginosa and S. maltophilia isolated from water. Dispensers A and B were disinfected with 10% (v/v) peracetic acid (PAA) and 3% (v/v) hydrogen peroxide (HP) respectively. Each dispenser was disinfected three times at monthly intervals with contact times of 10, 30 and 40 min. Water dispensed by the MWDs was collected immediately before and after each treatment and then twice weekly for the remaining period. Once a week a sample of the tap water entering the dispensers was tested. P. aeruginosa and S. maltophilia were enumerated in the 90 samples collected during 6 months. In the output water from the dispensers before the first treatment, the number of the bacteria was 3 to 4 log cfu/100 mL. Treatment with PAA greatly reduced the numbers of P. aeruginosa and S. maltophilia in the dispensed water initially. However, by 2 days after treatment, the numbers increased and remained high. In the case of disinfection with HP for 40 min, P. aeruginosa was not detected in most of the samples (73.7%). Numbers of S. maltophilia decreased with increasing time after treatment.

  15. Uptake and expression of bacterial and cyanobacterial genes by isolated cucumber etioplasts

    Energy Technology Data Exchange (ETDEWEB)

    Daniell, H.; McFadden, B.A.

    1987-09-01

    The uptake and expression by plastids isolated from dark-grown cucumber cotyledons (etioplasts) of two pUC derivatives, pCS75 and pUC9-CM, respectively carrying genes for the large and small subunits of ribulose bisphosphate carboxylase/oxygenase of Anacystis nidulans or chloramphenicol acetyltransferase, is reported. Untreated etioplasts take up only 3% as much DNA as that taken up by EDTA-washed etioplasts after 2 hr of incubation with nick-translated (/sup 32/P)-pCS75. The presence or absence of light does not affect DNA uptake, binding, or breakdown by etioplasts. Calcium or magnesium ions inhibit DNA uptake by 86% but enhance binding and breakdown of donor DNA by EDTA-treated etioplasts. Uncouplers that abolish membrane potential, transmembrane proton gradient, or both do not affect DNA uptake, binding, or breakdown by etioplasts. However, both DNA uptake and binding are severely inhibited by ATP. After the incubation of EDTA-treated etioplasts with pCS75, immunoprecipitation using antiserum to the small subunit of ribulose bisphosphate carboxylase/oxygenase from A. nidulans reveals the synthesis of small subunits. Treatment of etioplasts with 10 mM EDTA shows a 10-min duration to be optimal for the expression of chloramphenicol acetyltransferase encoded by pUC9-CM. A progressive increase in the expression of this enzyme is observed with an increase in the concentration of pUC9-CM in the DNA uptake medium. The plasmid-dependent incorporation of (/sup 35/S) methionine by EDTA-treated organelles declines markedly during cotyledon greening in vivo.

  16. An outbreak of trimethoprim/sulfamethoxazole-resistant Stenotrophomonas maltophilia meningitis associated with neuroendoscopy

    OpenAIRE

    Ching-Hsun Wang; Shih-Wei Hsu; Tung-Han Tsai; Ning-Chi Wang

    2014-01-01

    Stereotactic aspiration by neuroendoscopy for treatment of deep-seated intracranial hematomas is widely accepted because this procedure is minimally invasive and thereby reduces the probability of iatrogenic brain damage. Herein, we describe an outbreak of trimethoprim/sulfamethoxazole (TMP/SXT)-resistant Stenotrophomonas maltophilia meningitis, possibly from a contaminated neuroendoscopy, and review the previous use of antimicrobial therapies for this condition without TMP/SXT. This is the f...

  17. A Deep Nasopharyngeal Swab Versus Nonendoscopic Bronchoalveolar Lavage for Isolation of Bacterial Pathogens from Preweaned Calves With Respiratory Disease.

    Science.gov (United States)

    Van Driessche, L; Valgaeren, B R; Gille, L; Boyen, F; Ducatelle, R; Haesebrouck, F; Deprez, P; Pardon, B

    2017-05-01

    Nonendoscopic bronchoalveolar lavage (BAL) is a practical alternative for a deep nasopharyngeal swab (DNS) to sample the airways of a large number of calves in a short period of time. The extent of commensal overgrowth and agreement of BAL with DNS culture results in preweaned calves are unknown. To compare commensal overgrowth and bacterial culture results between DNS and BAL samples. A total of 183 preweaned calves (144 with bovine respiratory disease and 39 healthy animals). Cross-sectional study. Deep nasopharyngeal swab and BAL samples were taken from each calf and cultured to detect Pasteurellaceae and Mycoplasma bovis. Agreement and associations between culture results of DNS and BAL samples were determined by kappa statistics and logistic regression. Bronchoalveolar lavage samples were less often polymicrobial, more frequently negative and yielded more pure cultures compared to DNS, leading to a clinically interpretable culture result in 79.2% of the cases compared to only in 31.2% of the DNS samples. Isolation rates were lower in healthy animals, but not different between DNS and BAL samples. Only Histophilus somni was more likely to be isolated from BAL samples. In clinical cases, a polymicrobial DNS culture result did not increase the probability of a polymicrobial BAL result by ≥30%, nor did it influence the probability of a negative culture. A significant herd effect was noted for all observed relationships. Nonendoscopic BAL samples are far less overgrown by bacteria compared to DNS samples under the conditions of this study, facilitating clinical interpretation and resulting in a higher return on investment in bacteriologic culturing. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  18. Evaluation of antibacterial efficacy of anise wastes against some multidrug resistant bacterial isolates

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    Mohamed Khaled Ibrahim

    2017-01-01

    Full Text Available Antibiotic resistance in bacteria is becoming a serious problem, especially after the emergence of multidrug-resistant strains. To overcome this problem, new and effective antibacterials or resistance modulators are highly needed and plant kingdom represents a valuable source of these compounds. In this study we investigated the antibacterial and resistance modulatory activity of Aniseeds waste Residue Extract (ASWRE and Star Anise Waste Residue Extract (SAWRE (post-distillation against 100 isolates belonging to two Gram positive (Streptococcus pneumoniae and Staphylococcus aureus and four Gram negative bacteria (Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii and Pseudomonas aeruginosa. Phenolic compounds of anise wastes were determined by HPLC. The antibacterial activity of anise waste extracts assays were performed by using inhibition zone diameters, MIC and MBC. Evaluation of synergy interaction between anise waste extracts and certain known antibacterial drugs like Cephradine, Chloramphenicol, Tetracycline and Amoxicillin was carried out using disc diffusion method, MIC and the fractional inhibitory concentrations (FIC. The results showed that HPLC method has been developed for the determination of 25 phenolic compounds from waste extracts. Both ASWRE and SAWRE have significant antibacterial activity against all of the test bacteria. SAWRE was found to have higher amounts of phenolic compounds contents that might be responsible for their comparatively higher antibacteria activity than ASWRE. Irradiation at 10 and 30 kGy did not significantly affect the antibacterial activity of both ASWRE and SAWRE. The combination of anise waste extracts and the tested antibiotics mostly showed synergistic effect. Synergistic interaction was most expressed against Streptococcus pneumoniae (Sp1 and Staphylococcus aureus (Sa1 by Tetracycline and chloramphenicol; Pseudomonas aeruginosa (P2, Klebsiella pneumoniae (K3, Acinetobacter baumannii

  19. Control of biofouling by xanthine oxidase on seawater reverse osmosis membranes from a desalination plant: enzyme production and screening of bacterial isolates from the full-scale plant.

    Science.gov (United States)

    Nagaraj, V; Skillman, L; Li, D; Xie, Z; Ho, G

    2017-07-01

    Control of biofouling on seawater reverse osmosis (SWRO) membranes is a major challenge as treatments can be expensive, damage the membrane material and often biocides do not remove the polymers in which bacteria are embedded. Biological control has been largely ignored for biofouling control. The objective of this study was to demonstrate the effectiveness of xanthine oxidase enzyme against complex fouling communities and then identify naturally occurring bacterial strains that produce the free radical generating enzyme. Initially, 64 bacterial strains were isolated from different locations of the Perth Seawater Desalination Plant. In our preceding study, 25/64 isolates were selected from the culture collection as models for biofouling studies, based on their prevalence in comparison to the genomic bacterial community. In this study, screening of these model strains was performed using a nitroblue tetrazolium assay in the presence of hypoxanthine as substrate. Enzyme activity was measured by absorbance. Nine of 25 strains tested positive for xanthine oxidase production, of which Exiguobacterium from sand filters and Microbacterium from RO membranes exhibited significant levels of enzyme production. Other genera that produced xanthine oxidase were Marinomonas, Pseudomonas, Bacillus, Pseudoalteromonas and Staphylococcus. Strain variations were observed between members of the genera Microbacterium and Bacillus. Xanthine oxidase, an oxidoreductase enzyme that generates reactive oxygen species, is endogenously produced by many bacterial species. In this study, production of the enzyme by bacterial isolates from a full-scale desalination plant was investigated for potential use as biological control of membrane fouling in seawater desalination. We have previously demonstrated that free radicals generated by a commercially available xanthine oxidase in the presence of a hypoxanthine substrate, effectively dispersed biofilm polysaccharides on industrially fouled membranes

  20. Degradation pathways of 1-methylphenanthrene in bacterial Sphingobium sp. MP9-4 isolated from petroleum-contaminated soil.

    Science.gov (United States)

    Zhong, Jianan; Luo, Lijuan; Chen, Baowei; Sha, Sha; Qing, Qing; Tam, Nora F Y; Zhang, Yong; Luan, Tiangang

    2017-01-30

    Alkylated polycyclic aromatic hydrocarbons (PAHs) are abundant in petroleum, and alkylated phenanthrenes are considered as the primary PAHs during some oil spill events. Bacterial strain of Sphingobium sp. MP9-4, isolated from petroleum-contaminated soil, was efficient to degrade 1-methylphenanthrene (1-MP). A detailed metabolism map of 1-MP in this strain was delineated based on analysis of metabolites with gas chromatograph-mass spectrometer (GC-MS). 1-MP was initially oxidized via two different biochemical strategies, including benzene ring and methyl-group attacks. Benzene ring attack was initiated with dioxygenation of the non-methylated aromatic ring via similar degradation pathways of phenanthrene (PHE) by bacteria. For methyl-group attack, mono oxygenase system was involved and more diverse enzymes were needed than that of PHE degradation. This study enhances the understanding of the metabolic pathways of alkylated PAHs and shows the significant potential of Sphingobium sp. MP9-4 for the bioremediation of alkylated PAHs contaminated environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Partial Characterization of α-Galactosidic Activity from the Antarctic Bacterial Isolate, . LX-20 as a Potential Feed Enzyme Source

    Directory of Open Access Journals (Sweden)

    Inkyung Park

    2012-06-01

    Full Text Available An Antarctic bacterial isolate displaying extracellular α-galactosidic activity was named Paenibacillus sp. LX-20 based on 16S rRNA gene sequence analysis. Optimal activity for the LX-20 α-galactosidase occurred at pH 6.0–6.5 and 45°C. The enzyme immobilized on the smart polymer Eudragit L-100 retained 70% of its original activity after incubation for 30 min at 50°C, while the free enzyme retained 58% of activity. The enzyme had relatively high specificity for α-D-galactosides such as p-nitrophenyl-α-galactopyranoside, melibiose, raffinose and stachyose, and was resistant to some proteases such as trypsin, pancreatin and pronase. Enzyme activity was almost completely inhibited by Ag+, Hg2+, Cu2+, and sodium dodecyl sulfate, but activity was not affected by β-mercaptoethanol or EDTA. LX-20 α-galactosidase may be potentially useful as an additive for soybean processing in the feed industry.

  2. Radiosensitivities of bacterial isolates on minced chicken and poached chicken meal and their elimination following irradiation and chilled storage

    International Nuclear Information System (INIS)

    Adu-Gyamfi, A.; Nketsia-Tabiri, J.; Apea Bah, F.

    2008-01-01

    The radiosensitivities of Escherichia coli and Staphylococcus aureus on poached chicken meal (PCM) and minced chicken substrate (MCS) were determined. Effect of irradiation (0, 1, 2 kGy) on total viable cells (TVC) of PCM components was determined under chilled (3-5 o C) storage (0, 9, 14, 21 days) and challenge testing of the bacterial isolates with irradiation (0, 2, 3 kGy) was also conducted on PCM under chilled storage (0,7, 14, 21, 28 days). Additionally, sensory evaluation of the PCM components was assessed with irradiation (0, 2, 3 kGy) during chilled storage (0, 7, 14, 21 days). D 10 of E. coli on PCM and MCS were 0.18 and 0.25 kGy whiles those of S. aureus were 0.27 and 0.29 kGy, respectively. D 10 values for PCM E. coli. 2 kGy controlled TVC and extended the shelf life of meals to ≥14 days but 3 kGy was required to eliminate E. coli and S. aureus. Sensory qualities of the meal were not affected by an irradiation dose of 3 kGy

  3. Effects of viruses on bacterial functions under contrasting nutritional conditions for four species of bacteria isolated from Hong Kong waters

    Science.gov (United States)

    Liu, Hao; Yuan, Xiangcheng; Xu, Jie; Harrison, Paul J.; He, Lei; Yin, Kedong

    2015-09-01

    Free living viruses are ubiquitous in marine waters and concentrations are usually several times higher than the bacterial abundance. These viruses are capable of lysing host bacteria and therefore, play an important role in the microbial loop in oligotrophic waters. However, few studies have been conducted to compare the role of viruses in regulating bacterial abundance and heterotrophic activities between natural oligotrophic waters and anthropogenic influenced eutrophic waters. In this study, we examined viral effects on bacterial functions of four single bacterial species incubated with natural viral assemblages in seawater samples from eutrophic and oligotrophic waters. The viral-lysis of bacteria was significantly higher in eutrophic than oligotrophic waters. This suggests that viruses were capable of controlling bacterial abundance, respiration and production in the eutrophic waters. Cellular bacterial respiration and production was higher with viruses than without viruses, which was more evident in the oligotrophic waters. These results indicate that viruses can slow down bacterial consumption of oxygen and reduce bacteria-induced eutrophication effects in anthropogenic eutrophic waters, but switch to the role of sustaining the bacterial population when nutrients are limiting. There were bacterial species differences in resisting viral attack, which can influence the dominance and biodiversity of bacterial species in coastal waters.

  4. Isolation and characterisation of endocrine disruptor nonylphenol-using bacteria from South Africa

    Directory of Open Access Journals (Sweden)

    Lehlohonolo B. Qhanya

    2017-05-01

    Full Text Available Endocrine disrupting chemicals (EDCs are synthetic chemicals that alter the function of endocrine systems in animals including humans. EDCs are considered priority pollutants and worldwide research is ongoing to develop bioremediation strategies to remove EDCs from the environment. An understanding of indigenous microorganisms is important to design efficient bioremediation strategies. However, much of the information available on EDCs has been generated from developed regions. Recent studies have revealed the presence of different EDCs in South African natural resources, but, to date, studies analysing the capabilities of microorganisms to utilise/degrade EDCs have not been reported from South Africa. Here, we report for the first time on the isolation and enrichment of six bacterial strains from six different soil samples collected from the Mpumalanga Province, which are capable of utilising EDC nonylphenol as a carbon source. Furthermore, we performed a preliminary characterisation of isolates concerning their phylogenetic identification and capabilities to degrade nonylphenol. Phylogenetic analysis using 16S rRNA gene sequencing revealed that four isolates belonged to Pseudomonas and the remaining two belonged to Enterobacteria and Stenotrophomonas. All six bacterial species showed degradation of nonylphenol in broth cultures, as HPLC analysis revealed 41–46% degradation of nonylphenol 12 h after addition. The results of this study represent the beginning of identification of microorganisms capable of degrading nonylphenol, and pave the way for further exploration of EDC-degrading microorganisms from South Africa.

  5. Probing substrate binding to Metallo-β-Lactamase L1 from Stenotrophomonas maltophilia by using site-directed mutagenesis

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    Yates Robert B

    2002-02-01

    Full Text Available Abstract Background The metallo-β-lactamases are Zn(II-containing enzymes that hydrolyze the β-lactam bond in penicillins, cephalosporins, and carbapenems and are involved in bacterial antibiotic resistance. There are at least 20 distinct organisms that produce a metallo-β-lactamase, and these enzymes have been extensively studied using X-ray crystallographic, computational, kinetic, and inhibition studies; however, much is still unknown about how substrates bind and the catalytic mechanism. In an effort to probe substrate binding to metallo-β-lactamase L1 from Stenotrophomonas maltophilia, nine site-directed mutants of L1 were prepared and characterized using metal analyses, CD spectroscopy, and pre-steady state and steady state kinetics. Results Site-directed mutations were generated of amino acids previously predicted to be important in substrate binding. Steady-state kinetic studies using the mutant enzymes and 9 different substrates demonstrated varying Km and kcat values for the different enzymes and substrates and that no direct correlation between Km and the effect of the mutation on substrate binding could be drawn. Stopped-flow fluorescence studies using nitrocefin as the substrate showed that only the S224D and Y228A mutants exhibited weaker nitrocefin binding. Conclusions The data presented herein indicate that Ser224, Ile164, Phe158, Tyr228, and Asn233 are not essential for tight binding of substrate to metallo-β-lactamase L1. The results in this work also show that Km values are not reliable for showing substrate binding, and there is no correlation between substrate binding and the amount of reaction intermediate formed during the reaction. This work represents the first experimental testing of one of the computational models of the metallo-β-lactamases.

  6. Stenotrophomonas maltophilia virulence and specific variations in trace elements during acute lung infection: implications in cystic fibrosis.

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    Arianna Pompilio

    Full Text Available Metal ions are necessary for the proper functioning of the immune system, and, therefore, they might have a significant influence on the interaction between bacteria and host. Ionic dyshomeostasis has been recently observed also in cystic fibrosis (CF patients, whose respiratory tract is frequently colonized by Stenotrophomonas maltophilia. For the first time, here we used an inductively mass spectrometry method to perform a spatial and temporal analysis of the pattern of changes in a broad range of major trace elements in response to pulmonary infection by S. maltophilia. To this, DBA/2 mouse lungs were comparatively infected by a CF strain and by an environmental one. Our results showed that pulmonary ionomic profile was significantly affected during infection. Infected mice showed increased lung levels of Mg, P, S, K, Zn, Se, and Rb. To the contrary, Mn, Fe, Co, and Cu levels resulted significantly decreased. Changes of element concentrations were correlated with pulmonary bacterial load and markers of inflammation, and occurred mostly on day 3 post-exposure, when severity of infection culminated. Interestingly, CF strain - significantly more virulent than the environmental one in our murine model - provoked a more significant impact in perturbing pulmonary metal homeostasis. Particularly, exposure to CF strain exclusively increased P and K levels, while decreased Fe and Mn ones. Overall, our data clearly indicate that S. maltophilia modulates pulmonary metal balance in a concerted and virulence-dependent manner highlighting the potential role of the element dyshomeostasis during the progression of S. maltophilia infection, probably exacerbating the harmful effects of the loss of CF transmembrane conductance regulator function. Further investigations are required to understand the biological significance of these alterations and to confirm they are specifically caused by S. maltophilia.

  7. Characterization of bacterial diversity associated with calcareous deposits and drip-waters, and isolation of calcifying bacteria from two Colombian mines.

    Science.gov (United States)

    García G, Mariandrea; Márquez G, Marco Antonio; Moreno H, Claudia Ximena

    2016-01-01

    Bacterial carbonate precipitation has implications in geological processes and important biotechnological applications. Bacteria capable of precipitating carbonates have been isolated from different calcium carbonate deposits (speleothems) in caves, soil, freshwater and seawater around the world. However, the diversity of bacteria from calcareous deposits in Colombia, and their ability to precipitate carbonates, remains unknown. In this study, conventional microbiological methods and molecular tools, such as temporal temperature gradient electrophoresis (TTGE), were used to assess the composition of bacterial communities associated with carbonate deposits and drip-waters from two Colombian mines. A genetic analysis of these bacterial communities revealed a similar level of diversity, based on the number of bands detected using TTGE. The dominant phylogenetic affiliations of the bacteria, determined using 16S rRNA gene sequencing, were grouped into two phyla: Proteobacteria and Firmicutes. Within these phyla, seven genera were capable of precipitating calcium carbonates: Lysinibacillus, Bacillus, Strenotophomonas, Brevibacillus, Methylobacterium, Aeromicrobium and Acinetobacter. FTIR and SEM/EDX were used to analyze calcium carbonate crystals produced by isolated Acinetobacter gyllenbergii. The results showed that rhombohedral and angular calcite crystals with sizes of 90μm were precipitated. This research provides information regarding the presence of complex bacterial communities in secondary carbonate deposits from mines and their ability to precipitate calcium carbonate from calcareous deposits of Colombian mines. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Studies on the factors modulating indole-3-acetic acid production in endophytic bacterial isolates from Piper nigrum and molecular analysis of ipdc gene.

    Science.gov (United States)

    Jasim, B; Jimtha John, C; Shimil, V; Jyothis, M; Radhakrishnan, E K

    2014-09-01

    The study mainly aimed quantitative analysis of IAA produced by endophytic bacteria under various conditions including the presence of extract from Piper nigrum. Analysis of genetic basis of IAA production was also conducted by studying the presence and diversity of the ipdc gene among the selected isolates. Five endophytic bacteria isolated previously from P. nigrum were used for the study. The effect of temperature, pH, agitation, tryptophan concentration and plant extract on modulating IAA production of selected isolates was analysed by colorimetric method. Comparative and quantitative analysis of IAA production by colorimetric isolates under optimal culture condition was analysed by HPTLC method. Presence of ipdc gene and thereby biosynthetic basis of IAA production among the selected isolates were studied by PCR-based amplification and subsequent insilico analysis of sequence obtained. Among the selected bacterial isolates from P. nigrum, isolate PnB 8 (Klebsiella pneumoniae) was found to have the maximum yield of IAA under various conditions optimized and was confirmed by colorimetric, HPLC and HPTLC analysis. Very interestingly, the study showed stimulating effect of phytochemicals from P. nigrum on IAA production by endophytic bacteria isolated from same plant. This study is unique because of the selection of endophytes from same source for comparative and quantitative analysis of IAA production under various conditions. Study on stimulatory effect of phytochemicals on bacterial IAA production as explained in the study is a novel approach. Studies on molecular basis of IAA production which was confirmed by sequence analysis of ipdc gene make the study scientifically attractive. Even though microbial production of IAA is well known, current report on detailed optimization, effect of plant extract and molecular confirmation of IAA biosynthesis is comparatively novel in its approach. © 2014 The Society for Applied Microbiology.

  9. A rapid two-step algorithm detects and identifies clinical macrolide and beta-lactam antibiotic resistance in clinical bacterial isolates.

    Science.gov (United States)

    Lu, Xuedong; Nie, Shuping; Xia, Chengjing; Huang, Lie; He, Ying; Wu, Runxiang; Zhang, Li

    2014-07-01

    Aiming to identify macrolide and beta-lactam resistance in clinical bacterial isolates rapidly and accurately, a two-step algorithm was developed based on detection of eight antibiotic resistance genes. Targeting at genes linked to bacterial macrolide (msrA, ermA, ermB, and ermC) and beta-lactam (blaTEM, blaSHV, blaCTX-M-1, blaCTX-M-9) antibiotic resistances, this method includes a multiplex real-time PCR, a melting temperature profile analysis as well as a liquid bead microarray assay. Liquid bead microarray assay is applied only when indistinguishable Tm profile is observed. The clinical validity of this method was assessed on clinical bacterial isolates. Among the total 580 isolates that were determined by our diagnostic method, 75% of them were identified by the multiplex real-time PCR with melting temperature analysis alone, while the remaining 25% required both multiplex real-time PCR with melting temperature analysis and liquid bead microarray assay for identification. Compared with the traditional phenotypic antibiotic susceptibility test, an overall agreement of 81.2% (kappa=0.614, 95% CI=0.550-0.679) was observed, with a sensitivity and specificity of 87.7% and 73% respectively. Besides, the average test turnaround time is 3.9h, which is much shorter in comparison with more than 24h for the traditional phenotypic tests. Having the advantages of the shorter operating time and comparable high sensitivity and specificity with the traditional phenotypic test, our two-step algorithm provides an efficient tool for rapid determination of macrolide and beta-lactam antibiotic resistances in clinical bacterial isolates. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Bacterial community analysis in chlorpyrifos enrichment cultures via DGGE and use of bacterial consortium for CP biodegradation.

    Science.gov (United States)

    Akbar, Shamsa; Sultan, Sikander; Kertesz, Michael

    2014-10-01

    The organophosphate pesticide chlorpyrifos (CP) has been used extensively since the 1960s for insect control. However, its toxic effects on mammals and persistence in environment necessitate its removal from contaminated sites, biodegradation studies of CP-degrading microbes are therefore of immense importance. Samples from a Pakistani agricultural soil with an extensive history of CP application were used to prepare enrichment cultures using CP as sole carbon source for bacterial community analysis and isolation of CP metabolizing bacteria. Bacterial community analysis (denaturing gradient gel electrophoresis) revealed that the dominant genera enriched under these conditions were Pseudomonas, Acinetobacter and Stenotrophomonas, along with lower numbers of Sphingomonas, Agrobacterium and Burkholderia. Furthermore, it revealed that members of Bacteroidetes, Firmicutes, α- and γ-Proteobacteria and Actinobacteria were present at initial steps of enrichment whereas β-Proteobacteria appeared in later steps and only Proteobacteria were selected by enrichment culturing. However, when CP-degrading strains were isolated from this enrichment culture, the most active organisms were strains of Acinetobacter calcoaceticus, Pseudomonas mendocina and Pseudomonas aeruginosa. These strains degraded 6-7.4 mg L(-1) day(-1) of CP when cultivated in mineral medium, while the consortium of all four strains degraded 9.2 mg L(-1) day(-1) of CP (100 mg L(-1)). Addition of glucose as an additional C source increased the degradation capacity by 8-14 %. After inoculation of contaminated soil with CP (200 mg kg(-1)) disappearance rates were 3.83-4.30 mg kg(-1) day(-1) for individual strains and 4.76 mg kg(-1) day(-1) for the consortium. These results indicate that these organisms are involved in the degradation of CP in soil and represent valuable candidates for in situ bioremediation of contaminated soils and waters.

  11. Hydrocarbonoclastic bacteria isolated from petroleum contaminated sites in Tunisia: isolation, identification and characterization of the biotechnological potential.

    Science.gov (United States)

    Mahjoubi, Mouna; Jaouani, Atef; Guesmi, Amel; Ben Amor, Sonia; Jouini, Ahlem; Cherif, Hanen; Najjari, Afef; Boudabous, Abdellatif; Koubaa, Nedra; Cherif, Ameur

    2013-09-25

    Petroleum hydrocarbons are important energy resources used by industry and in our daily life, whose production contributes highly to environmental pollution. To control such risk, bioremediation constitutes an environmentally friendly alternative technology that has been established and applied. It constitutes the primary mechanism for the elimination of hydrocarbons from contaminated sites by natural existing populations of microorganisms. In this work, a collection of 125 strains, adapted to grow on minimal medium supplemented with crude oil, was obtained from contaminated sediments and seawater from a refinery harbor of the Bizerte coast in the North of Tunisia. The diversity of the bacterial collection was analyzed by amplification of the internal transcribed spacers between the 16S and the 23S rRNA genes (ITS-PCR) and by 16S rRNA sequencing. A total of 36 distinct ITS haplotypes were detected on agarose matrix. Partial 16S rRNA gene sequencing performed on 50 isolates showed high level of identity with known sequences. Strains were affiliated to Ochrabactrum, Sphingobium, Acinetobacter, Gordonia, Microbacterium, Brevundimonas, Novosphingobium, Stenotrophomonas, Luteibacter, Rhodococcus, Agrobacterium, Achromobacter, Bacilllus, Kocuria and Pseudomonas genera. Acinetobacter and Stenotrophomons were found to be the most abundant species characterized by a marked microdiversity as shown through ITS typing. Culture-independent approach (DGGE) showed high diversity in the microbial community in all the studied samples with a clear correlation with the hydrocarbon pollution rate. Sequencing of the DGGE bands revealed a high proportion of Proteobacteria represented by the Alpha and Gamma subclasses. The predominant bacterial detected by both dependent and independent approaches were the Proteobacteria. The biotechnological potential of the isolates revealed a significant production of biosurfactants with important emulsification activities useful in bioremediation

  12. Stenotrophomonas maltophilia as an Emerging Ubiquitous Pathogen: Looking Beyond Contemporary Antibiotic Therapy

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    Anthony A. Adegoke

    2017-11-01

    Full Text Available Stenotrophomonas maltophilia is a commensal and an emerging pathogen earlier noted in broad-spectrum life threatening infections among the vulnerable, but more recently as a pathogen in immunocompetent individuals. The bacteria are consistently being implicated in necrotizing otitis, cutaneous infections including soft tissue infection and keratitis, endocarditis, meningitis, acute respiratory tract infection (RTI, bacteraemia (with/without hematological malignancies, tropical pyomyositis, cystic fibrosis, septic arthritis, among others. S. maltophilia is also an environmental bacteria occurring in water, rhizospheres, as part of the animals' microflora, in foods, and several other microbiota. This review highlights clinical reports on S. maltophilia both as an opportunistic and as true pathogen. Also, biofilm formation as well as quorum sensing, extracellular enzymes, flagella, pili/fimbriae, small colony variant, other virulence or virulence-associated factors, the antibiotic resistance factors, and their implications are considered. Low outer membrane permeability, natural MDR efflux systems, and/or resistance genes, resistance mechanisms like the production of two inducible chromosomally encoded β-lactamases, and lack of carefully compiled patient history are factors that pose great challenges to the S. maltophilia control arsenals. The fluoroquinolone, some tetracycline derivatives and trimethoprim-sulphamethaxole (TMP-SMX were reported as effective antibiotics with good therapeutic outcome. However, TMP-SMX resistance and allergies to sulfa together with high toxicity of fluoroquinolone are notable setbacks. S. maltophilia's production and sustenance of biofilm by quorum sensing enhance their virulence, resistance to antibiotics and gene transfer, making quorum quenching an imperative step in Stenotrophomonas control. Incorporating several other proven approaches like bioengineered bacteriophage therapy, Epigallocatechin-3-gallate (EGCG

  13. Physiology and bioprocess of single cell of Stenotrophomonas maltophilia in bioremediation of co-existed benzo[a]pyrene and copper.

    Science.gov (United States)

    Shuona, Chen; Hua, Yin; Jingjing, Chang; Hui, Peng; Zhi, Dang

    2017-01-05

    Polycyclic aromatic hydrocarbons (PAHs) and heavy metals are generally present in mixtures in the e-waste dismantling areas, posing serious health risk to the local people. Bioremediation has been considered as a promising approach for PAHs and heavy metals removal. In this study, we applied flow cytometry to obtain a better understanding of membrane potential (MP), apoptosis and cell cycle of Stenotrophomonas maltophilia affected by combined pollutants of benzo[a]pyrene(BaP) and Cu(II). The results showed that BaP was the main factor damaging the cell membrane and influencing the MP. S. maltophilia could even protect against upsetting situation by encouraging early apoptosis, whereby compromised cells committed suicide, as a result, which, in turn, facilitated the metabolism of the bacteria with high-vitality. Furthermore, even if the bacterial cell division was blocked and stopped reproduction, a large number of key enzymes inside cells could still be used for degradation of BaP. The expression of protein related to the transport and metabolism of BaP, regulation of redox reactions and phosphorylation in bacterial cell during bioprocess were evident different. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Biogenic SeNPs from Bacillus mycoides SelTE01 and Stenotrophomonas maltophilia SelTE02: Characterization with reference to their associated organic coating

    Science.gov (United States)

    Piacenza, Elena; Bulgarini, Alessandra; Lampis, Silvia; Vallini, Giovanni; Turner, Raymond J.

    2017-08-01

    The exploitation of biological systems (i.e. plants, fungi and bacteria) for the production of nanomaterials relies on their ability to bioconvert toxic metal(loid) ions into their less toxic and bioavailable elemental states forming mainly nanoparticles (NPs) or nanorods (NRs). Further, these methods of nanomaterial production are nowadays recognized as eco-friendly alternatives to the chemical synthesis processes. A common feature among the so-called biogenic nanomaterials is the presence of an organic layer surrounding them. However, we are just learning the existing relation between biogenic nanostructures and their organic material. Our work is focused on the study of bacterial strains for the production of selenium nanoparticles (SeNPs) as end product of selenite (SeO32 -) bioconversion. In this context, our previous reports described the ability of two bacteria, namely Bacillus mycoides SelTE01 and Stenotrophomonas maltophilia SelTE02, to generate SeNPs, which were surrounded by organic material. Here, the potential role of this organic material as stabilizing agent of SeNPs was investigated altering both the bacteria cells culturing and the SeNPs extraction procedure, in order to understand the interaction between these two elements in suspension. As a result, SeNPs produced by both bacterial strains showed the tendency to aggregate when subjected to the treatments tested, suggesting an involvement of the surrounding organic material in their stabilization in suspension.

  15. Characterization of plant growth promoting traits of bacterial isolates from the rhizosphere of barley (Hordeum vulgare L.) and tomato (Solanum lycopersicon L.) grown under Fe sufficiency and deficiency.

    Science.gov (United States)

    Scagliola, M; Pii, Y; Mimmo, T; Cesco, S; Ricciuti, P; Crecchio, C

    2016-10-01

    Plant Growth Promoting Bacteria (PGPB) are considered a promising approach to replace the conventional agricultural practices, since they have been shown to affect plant nutrient-acquisition processes by influencing nutrient availability in the rhizosphere and/or those biochemical processes determining the uptake at root level of nitrogen (N), phosphorus (P), and iron (Fe), that represent the major constraints for crop productivity worldwide. We have isolated novel bacterial strains from the rhizosphere of barley (Hordeum vulgare L.) and tomato (Solanum lycopersicon L.) plants, previously grown in hydroponic solution (either Fe deficient or Fe sufficient) and subsequently transferred onto an agricultural calcareous soil. PGPB have been identified by molecular tools and characterized for their capacity to produce siderophores and indole-3-acetic acid (IAA), and to solubilize phosphate. Selected bacterial isolates, showing contemporarily high levels of the three activities investigated, were finally tested for their capacity to induce Fe reduction in cucumber roots two isolates, from barley and tomato plants under Fe deficiency, significantly increased the root Fe-chelate reductase activity; interestingly, another isolate enhanced the reduction of Fe-chelate reductase activity in cucumber plant roots, although grown under Fe sufficiency. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. An outbreak of trimethoprim/sulfamethoxazole-resistant Stenotrophomonas maltophilia meningitis associated with neuroendoscopy

    Directory of Open Access Journals (Sweden)

    Ching-Hsun Wang

    2014-01-01

    Full Text Available Stereotactic aspiration by neuroendoscopy for treatment of deep-seated intracranial hematomas is widely accepted because this procedure is minimally invasive and thereby reduces the probability of iatrogenic brain damage. Herein, we describe an outbreak of trimethoprim/sulfamethoxazole (TMP/SXT-resistant Stenotrophomonas maltophilia meningitis, possibly from a contaminated neuroendoscopy, and review the previous use of antimicrobial therapies for this condition without TMP/SXT. This is the first reported outbreak of TMP/SXT-resistant S. maltophilia meningitis. The discussion emphasizes the importance of adequate disinfection processes before and after endoscopic neurosurgery and the use of therapeutic options other than TMP/SXT when encountering S. maltophilia meningitis.

  17. Expression and Functions of CreD, an Inner Membrane Protein in Stenotrophomonas maltophilia

    OpenAIRE

    Huang, Hsin-Hui; Lin, Yi-Tsung; Chen, Wei-Ching; Huang, Yi-Wei; Chen, Shiang-Jiuun; Yang, Tsuey-Ching

    2015-01-01

    CreBC is a highly conserved two-component regulatory system (TCS) in several gram-negative bacteria, including Escherichia coli, Aeromonas spp., Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. CreD is a conserved gene that encodes a predicted inner-membrane protein and is located near the creBC loci. Activation of CreBC increases creD expression; therefore, creD expression is generally used as a measure of CreBC activation in E. coli, Aeromonas spp., and P. aeruginosa systems. In th...

  18. Susceptibilidad antimicrobiana de aislamientos bacterianos causantes de infecciones comunitarias Antimicrobial susceptibility of bacterial isolates causing community infections

    Directory of Open Access Journals (Sweden)

    Luis Enrique Cabrera Rodríguez

    2007-03-01

    Full Text Available La resistencia bacteriana es un problema de salud creciente a nivel mundial. Se realiz�� un estudio descriptivo-retrospectivo en el Laboratorio de Microbiología Clínica, perteneciente al Centro Municipal de Higiene y Epidemiología del municipio de Güines, en el período comprendido desde enero a diciembre de 2005, para conocer la susceptibilidad a los agentes antimicrobianos de elección de 750 cepas que incluyeron los microorganismos siguientes: Staphylococcus aureus (n=250, Escherichia coli (n= 250 y Pseudomonas aeruginosa (n= 250, aislados de diferentes muestras clínicas (secreción ótica, lesiones de piel, pus de heridas, de la faringe y orina de pacientes ambulatorios con signos y síntomas de infección, de 5 municipios del este de La Habana. Se apreciaron altos niveles de resistencia en las cepas de Staphylococcus aureus a la penicilina, la oxacilina y la eritromicina; en Escherichia coli al trimetoprim-sulfametoxazol, al ácido nalidíxico y la ampicilina; y en el caso de Pseudomonas aeruginosa no se encontraron altos niveles de resistencia a las drogas investigadas. Los resultados ponen en evidencia la necesidad de perfeccionar y continuar la vigilancia microbiológica de la resistencia a los fármacos antimicrobianos.Bacterial resistance is an increasing health problem worldwide. A descriptive, retrospective study was conducted in the Laboratory of Clinical Microbiology of the Municipal Center of Hygiene and Epidemiology of Güines municipality, from January to December 2005, to know the susceptibility to the antimicrobial elective agents of 750 strains that included the following microorganisms: Staphylococcus aureus (n=250, Escherichia coli (n=250 and Pseudomonas aeruginosa (n=250, isolated from different clinical samples (ear secretion, skin lesions, wound pus, pharynx and urine from ambulatory patients with signs and symptoms of infection from 5 municipalities of Eastern Havana. High levels of resistance were found in the

  19. Degree of bacterial contamination and antibiotic susceptibility pattern of isolates from housekeeping surfaces in operating rooms and surgical wards at Jimma University Specialized Hospital, south west Ethiopia.

    Science.gov (United States)

    Genet, Chalachew; Kibru, Gebre; Hemalatha, Kannan

    2012-01-01

    The role of the hospital environment as a reservoir of potential pathogens has received increasing attention. There are several reports demonstrating contamination of a wide variety of environmental sites in operating rooms (ORs) and surgical wards (SWs) which lead to nosocomial spread. To determine the degree of bacterial contamination and antibiotic susceptibility pattern of isolates from floor and tabletop surfaces in ORs and SWs at Jimma University Specialized Hospital (JUSH). A cross sectional study was conducted on 144 floor and tabletop surfaces from October to January 2009/2010. Samples were investigated for identification of bacterial species following standard procedures and antimicrobial susceptibility tests were performed using disc diffusion technique. The data was analyzed using SPSS version 16 and compared with the proposed standard value. The mean aerobic colony counts (ACCs) for tabletop surfaces (34 CFU/cm2) and floors (19CFU/cm2) in SWs were significantly higher than the set ACC standard for hand contact surfaces (< 5 CFU/cm2) P < 0.00. The ACCs obtained from tabletop surfaces (6.2 CFU/cm2) and floors (10.1CFU/cm2) in ORs were also exceeding the standard. Over 55% of gram negative bacteria were identified from Critical Zone of ORs. Staphylococcus aureus was the must frequently isolated bacterium accounting 33.3% followed by Escherichia coli and Klebsiella spp each with 11.1%. Moreover, S. aureus showed 100% resistance to methicillin and multidrug resistant Enterobacteriaceae were also seen in more than 90 % of isolates. An increased bacterial contamination was measured in both ORs and SWs of the JUSH and the isolated bacteria were also resistant for most of the antibiotics used as a treatment options in the study area. Therefore, appropriate infection control measures needs to be taken to keep the contamination level within the proposed standard.

  20. Isolation of identical nitrilase genes from multiple bacterial strains and real-time PCR detection of the genes from soils provides evidence of horizontal gene transfer.

    Science.gov (United States)

    Coffey, Lee; Clarke, Adrienne; Duggan, Patrick; Tambling, Karen; Horgan, Serenia; Dowling, David; O'Reilly, Catherine

    2009-10-01

    Bacterial enzymes capable of nitrile hydrolysis have significant industrial potential. Microbacterium sp. AJ115, Rhodococcus erythropolis AJ270 and AJ300 were isolated from the same location in England and harbour identical nitrile hydratase/amidase gene clusters. Strain AJ270 has been well studied due to its nitrile hydratase and amidase activity. R. erythropolis ITCBP was isolated from Denmark and carries a very similar nitrile hydratase/amidase gene cluster. In this study, an identical nitrilase gene (nit1) was isolated from the four strains, and the nitrilase from strain AJ270 cloned and expressed in Escherichia coli. Analysis of the recombinant nitrilase has shown it to be functional with activity demonstrated towards phenylacetonitrile. A real-time PCR TaqMan assay was developed that allowed nit1 detection directly from soil enrichment cultures without DNA extraction, with nit1 detected in all samples tested. Real-time PCR screening of isolates from these soils resulted in the isolation of nit1 and also very similar nitrilase gene nit2 from a number of Burkholderia sp. The genes nit1 and nit2 have also been detected in many bacteria of different genera but are unstable in these isolates. It is likely that the genes were acquired by horizontal gene transfer and may be wide-spread in the environment.

  1. Bacterial Microbiota of Rice Roots: 16S-Based Taxonomic Profiling of Endophytic and Rhizospheric Diversity, Endophytes Isolation and Simplified Endophytic Community.

    Science.gov (United States)

    Moronta-Barrios, Felix; Gionechetti, Fabrizia; Pallavicini, Alberto; Marys, Edgloris; Venturi, Vittorio

    2018-02-11

    Rice is currently the most important food crop in the world and we are only just beginning to study the bacterial associated microbiome. It is of importance to perform screenings of the core rice microbiota and also to develop new plant-microbe models and simplified communities for increasing our understanding about the formation and function of its microbiome. In order to begin to address this aspect, we have performed a 16S rDNA taxonomic bacterial profiling of the rhizosphere and endorhizosphere of two high-yield rice cultivars-Pionero 2010 FL and DANAC SD20A-extensively grown in Venezuela in 2014. Fifteen putative bacterial endophytes were then isolated from surface-sterilized roots and further studied in vitro and in planta . We have then performed inoculation of rice seedlings with a simplified community composed by 10 of the isolates and we have tracked them in the course of 30 days in greenhouse cultivation. The results obtained suggest that a set was able to significantly colonize together the rice endorhizospheres, indicating possible cooperation and the ability to form a stable multispecies community. This approach can be useful in the development of microbial solutions for a more sustainable rice production.

  2. Influence of bacterial strains isolated from lead-polluted soil and their interactions with arbuscular mycorrhizae on the growth of Trifolium pratense L. under lead toxicity.

    Science.gov (United States)

    Vivas, A; Azcón, R; Biró, B; Barea, J M; Ruiz-Lozano, J M

    2003-10-01

    We isolated two bacterial strains from an experimentally lead (Pb)-polluted soil in Hungary, 10 years after soil contamination. These strains represented the two most abundant cultivable bacterial groups in such soil, and we tested their influence on Trifolium pratense L. growth and on the functioning of native mycorrhizal fungi under Pb toxicity in a second Pb-spiked soil. Our results showed that bacterial strain A enhanced plant growth, nitrogen and phosphorus accumulations, nodule formation, and mycorrhizal infection, demonstrating its plant-growth-promoting activity. In addition, strain A decreased the amount of Pb absorbed by plants, when expressed on a root weight basis, because of increased root biomass due to the production of indoleacetic acid. The positive effect of strain A was not only evident after a single inoculation but also in dual inoculation with arbuscular mycorrhizal fungi. Strain A also exhibited higher tolerance than strain B when cultivated under increasing Pb levels in the spiked soil. Molecular identification unambiguously placed strain A within the genus Brevibacillus. We showed that it is important to select the most tolerant and efficient bacterial strain for co-inoculation with arbuscular mycorrhizal fungi to promote effective symbiosis and thus stimulate plant growth under adverse environmental conditions, such as heavy-metal contamination.

  3. Extracellular polymeric substances (EPS) producing bacterial strains of municipal wastewater sludge: isolation, molecular identification, EPS characterization and performance for sludge settling and dewatering.

    Science.gov (United States)

    Bala Subramanian, S; Yan, S; Tyagi, R D; Surampalli, R Y

    2010-04-01

    Wastewater treatment plants often face the problems of sludge settling mainly due to sludge bulking. Generally, synthetic organic polymer and/or inorganic coagulants (ferric chloride, alum and quick lime) are used for sludge settling. These chemicals are very expensive and further pollute the environment. Whereas, the bioflocculants are environment friendly and may be used to flocculate the sludge. Extracellular polymeric substances (EPS) produced by sludge microorganisms play a definite role in sludge flocculation. In this study, 25 EPS producing strains were isolated from municipal wastewater treatment plant. Microorganisms were selected based on EPS production properties on solid agar medium. Three types of EPS (slime, capsular and bacterial broth mixture of both slime and capsular) were harvested and their characteristics were studied. EPS concentration (dry weight), viscosity and their charge (using a Zetaphoremeter) were also measured. Bioflocculability of obtained EPS was evaluated by measuring the kaolin clay flocculation activity. Six bacterial strains (BS2, BS8, BS9, BS11, BS15 and BS25) were selected based on the kaolin clay flocculation. The slime EPS was better for bioflocculation than capsular EPS and bacterial broth. Therefore, extracted slime EPS (partially purified) from six bacterial strains was studied in terms of sludge settling [sludge volume index (SVI)] and dewatering [capillary suction time (CST)]. Biopolymers produced by individual strains substantially improved dewaterability. The extracted slime EPS from six different strains were partially characterized. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  4. Isolasi dan Identifikasi Bakteri dari Tinja Orangutan Penderita Gangguan Gastrointestinal (BACTERIAL ISOLATION AND IDENTIFICATION IN FAECES OF ORANGUTAN WITH GASTROINTESTINAL DISTURBANCE

    Directory of Open Access Journals (Sweden)

    Michael Haryadi Wibowo

    2016-03-01

    Full Text Available Orangutans are among protected animals by the law. One of orangutans’ main health problems isgastrointestinal disease due to bacterial infection. Microbiological data of causative agent of illness inorangutan still not much reported scientifically. This research aim was to identify causative agent ofbacterial infection on gastrointestinal disorder in orangutan isolated from stool samples. The sampleswere collected from Yayasan Konservasi Alam Yogyakarta and Borneo Orangutan Survival, Semboja,Kalimantan Timur. Fresh fecal samples were collected using sterile swab and put them into a steriletransport media. To achieve pure cultures, bacterial isolation was performed by using plate streaking onselective media. Gram stain was done to confirm the cell uniformity and morphology. Bacterialidentification was performed according to Bergey’s Manual Determinative Bacteriology on some biochemicalcharacters to determine the isolated bacteria. The result showed that three bacteria were identified fromstool samples orangutan from Yayasan Konservasi Alam Yogyakarta, i.e.: Citrobacter amalonaticus,Providensia rustigianii, and Proteus mirabilis. Meanwhile, three bacteria, which were Klebsiella planticola,Enterobanter agglomerans and Escherichia coli, were also identified in samples taken from Borneo orangutan.

  5. The impact of animal age, bacterial coinfection, and isolate pathogenicity on the shedding of Porcine reproductive and respiratory syndrome virus in aerosols from experimentally infected pigs

    Science.gov (United States)

    Cho, Jenny G.; Dee, Scott A.; Deen, John; Trincado, Carlos; Fano, Eduardo; Jiang, Yin; Faaberg, Kay; Murtaugh, Michael P.; Guedes, Alonso; Collins, James E.; Joo, Han Soo

    2006-01-01

    The objective of this study was to evaluate the role of different variables (animal age, bacterial coinfection, and isolate pathogenicity) on the shedding of Porcine reproductive and respiratory syndrome virus (PRRSV) in aerosols. Animals were grouped according to age (2 versus 6 mo) and inoculated with a PRRSV isolate of either low (MN-30100) or high (MN-184) pathogenicity. Selected animals in each group were also inoculated with Mycoplasma hyopneumoniae. The pigs were anesthetized and aerosol samples (1000 breaths/sample) collected on alternating days from 1 to 21 after PRRSV inoculation. The results indicated that animal age (P = 0.09), M. hyopneumoniae coinfection (P = 0.09), and PRRSV isolate pathogenicity (P = 0.15) did not significantly influence the concentration of PRRSV in aerosols. However, inoculation with the PRRSV MN-184 isolate significantly increased the probability of aerosol shedding (P = 0.00005; odds ratio = 3.22). Therefore, the shedding of PRRSV in aerosols may be isolate-dependent. PMID:17042383

  6. Degradation and mineralization of high-molecular-weight polycyclic aromatic hydrocarbons by defined fungal-bacterial cocultures

    International Nuclear Information System (INIS)

    Boonchan, S.; Britz, M.L.; Stanley, G.A.

    2000-01-01

    This study investigated the biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) in liquid media and soil by bacteria (Stenotrophomonas maltophilia VUN 10,010 and bacterial consortium VUN 10,009) and a fungus (Penicillium janthinellum VUO 10,201) that were isolated from separate creosote- and manufactured-gas plant-contaminated soils. The bacteria could use pyrene as their sole carbon and energy source in a basal salts medium (BSM) and mineralized significant amounts of benzo[a]pyrene cometabolically when pyrene was also present in BSM. P. janthinellum VUO 10,201 could not utilize any high-molecular-weight PAH as sole carbon and energy source but could partially degrade these if cultured in a nutrient broth. Although small amounts of chrysene, benz[a]pyrene, and dibenz[a,h]anthracene were degraded by axenic cultures of these isolates in BSM containing a single PAH, such conditions did not support significant microbial growth or PAH mineralization. However, significant degradation of, and microbial growth on, pyrene, chrysene, benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene, each as a single PAH in BSM, occurred when P. janthinellum VUO 10,201 and either bacterial consortium VUN 10,009 or S. maltophilia VUN 10,010 were combined in the one culture, i.e., fungal-bacterial cocultures: 25% of the benzo[a]pyrene was mineralized to CO 2 by these cocultures over 49 days, accompanied by transient accumulation and disappearance of intermediates detected by high-pressure liquid chromatography. Inoculation of fungal-bacterial cocultures into PAH-contaminated soil resulted in significantly improved degradation of high-molecular-weight PAHs, benzo[a]pyrene mineralization, and reduction in the mutagenicity of organic soil extracts, compared with the indigenous microbes and soil amended with only axenic inocula

  7. Endophytic cultivable bacterial community obtained from the Paullinia cupana seed in Amazonas and Bahia regions and its antagonistic effects against Colletotrichum gloeosporioides.

    Science.gov (United States)

    Silva, Maria Carolina Santos E; Polonio, Julio Cesar; Quecine, Maria Carolina; Almeida, Tiago Tognolli de; Bogas, Andréa Cristina; Pamphile, João Alencar; Pereira, José Odair; Astolfi-Filho, Spartaco; Azevedo, João Lucio

    2016-09-01

    Guarana (Paullinia cupana var. sorbilis) is a plant from the Amazonas region with socio-economic importance. However, guarana production has been increasingly affected by unfavorable conditions resulting from anthracnose, caused by the Colletotrichum fungal genus, which primarily affects mainly the Amazonas region. The aim of the present study was to isolate bacterial endophytes from the seeds of guarana plants obtained from Amazonas region and the Northeast state of Bahia, a region where this disease is not a problem for guarana plantations. The number of bacterial Colony Forming Units (CFU/g seeds) was 2.4 × 10(4) from the Bahia and 2.9 × 10(4) from the Amazonas region. One hundred and two isolated bacteria were evaluated in vitro against the phytopathogenic strain Colletotrichum gloeosporioides L1. These isolates were also analyzed for the enzymatic production of amylase, cellulase, protease, pectinase, lipase and esterase. Approximately 15% of isolates, showing high antagonistic activity, and the production of at least one enzyme were identified through the partial sequencing of 16S rDNA. The genus Bacillus was the most frequently observed, followed by Paenibacillus, Ochrobactrum, Microbacterium and Stenotrophomonas. Proteolytic activity was observed in 24 isolates followed by amylolytic, pectinolytic and cellulolytic activities. No esterase and lipase production was detected. Most of the isolates, showing antagonistic effects against C. gloeosporioides and high enzymatic activities, were isolated from the anthracnose-affected region. A biocontrol method using the endophytes from guarana seeds could be applied in the future, as these bacteria are vertically transferred to guarana seedlings. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    Science.gov (United States)

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Evaluation of anti-bacterial and anti-oxidant potential of andrographolide and echiodinin isolated from callus culture of Andrographis paniculata Nees

    Science.gov (United States)

    Arifullah, Mohmmed; Namsa, Nima Dandu; Mandal, Manabendra; Chiruvella, Kishore Kumar; Vikrama, Paritala; Gopal, Ghanta Rama

    2013-01-01

    Objective To evaluate the anti-bacterial and anti-oxidant activity of andrographolide (AND) and echiodinin (ECH) of Andrographis paniculata. Methods In this study, an attempt has been made to demonstrate the anti-microbial and anti-oxidant activity of isolated AND and ECH by broth micro-dilution method and 2,2-diphenyl-2-picryl-hydrazyl (DPPH) assay, respectively. Structure elucidation was determined by electro-spray ionization-MSD, NMR (1H and 13C) and IR spectra. Results AND was effective against most of the strains tested including Mycobacterium smegmatis, showing broad spectrum of growth inhibition activity with Minimum inhibitory concentration values against Staphylococcus aureus (100 µg/mL), Streptococcus thermophilus (350 µg/mL) Bacillus subtilis (100 µg/mL), Escherichia coli (50 µg/mL), Mycobacterium smegmatis (200 µg/mL), Klebsiella pneumonia (100 µg/mL), and Pseudomonas aeruginosa (200 µg/mL). ECH showed specific anti-bacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa at a concentration higher than 225 µg/mL. Both AND and ECH were not effective against the two yeast strains, Candida albicans and Saccharomyces cerevisiae tested in this study. Conclusion This preliminary study showed promising anti-bacterial activity and moderate free radical scavenging activity of AND and ECH, and it may provide the scientific rationale for its popular folklore medicines. PMID:23905016

  10. Comparative genomics of non-pseudomonal bacterial species colonising paediatric cystic fibrosis patients

    Directory of Open Access Journals (Sweden)

    Kate L. Ormerod

    2015-09-01

    Full Text Available The genetic disorder cystic fibrosis is a life-limiting condition affecting ∼70,000 people worldwide. Targeted, early, treatment of the dominant infecting species, Pseudomonas aeruginosa, has improved patient outcomes; however, there is concern that other species are now stepping in to take its place. In addition, the necessarily long-term antibiotic therapy received by these patients may be providing a suitable environment for the emergence of antibiotic resistance. To investigate these issues, we employed whole-genome sequencing of 28 non-Pseudomonas bacterial strains isolated from three paediatric patients. We did not find any trend of increasing antibiotic resistance (either by mutation or lateral gene transfer in these isolates in comparison with other examples of the same species. In addition, each isolate contained a virulence gene repertoire that was similar to other examples of the relevant species. These results support the impaired clearance of the CF lung not demanding extensive virulence for survival in this habitat. By analysing serial isolates of the same species we uncovered several examples of strain persistence. The same strain of Staphylococcus aureus persisted for nearly a year, despite administration of antibiotics to which it was shown to be sensitive. This is consistent with previous studies showing antibiotic therapy to be inadequate in cystic fibrosis patients, which may also explain the lack of increasing antibiotic resistance over time. Serial isolates of two naturally multi-drug resistant organisms, Achromobacter xylosoxidans and Stenotrophomonas maltophilia, revealed that while all S. maltophilia strains were unique, A. xylosoxidans persisted for nearly five years, making this a species of particular concern. The data generated by this study will assist in developing an understanding of the non-Pseudomonas species associated with cystic fibrosis.

  11. Endophytic bacterial flora in root and stem tissues of black pepper (Piper nigrum L.) genotype: isolation, identification and evaluation against Phytophthora capsici.

    Science.gov (United States)

    Aravind, R; Kumar, A; Eapen, S J; Ramana, K V

    2009-01-01

    To isolate and identify black pepper (Piper nigrum L) associated endophytic bacteria antagonistic to Phytophthora capsici causing foot rot disease. Endophytic bacteria (74) were isolated, characterized and evaluated against P. capsici. Six genera belong to Pseudomonas spp (20 strains), Serratia (1 strain), Bacillus spp. (22 strains), Arthrobacter spp. (15 strains), Micrococcus spp. (7 strains), Curtobacterium sp. (1 strain) and eight unidentified strains were isolated from internal tissues of root and stem. Three isolates, IISRBP 35, IISRBP 25 and IISRBP 17 were found effective for Phytophthora suppression in multilevel screening assays which recorded over 70% disease suppression in greenhouse trials. A species closest match (99% similarity) of IISRBP 35 was established as Pseudomonas aeruginosa (Pseudomonas EF568931), IISRBP 25 as P. putida (Pseudomonas EF568932), and IISRBP 17 as Bacillus megaterium (B. megaterium EU071712) based on 16S rDNA sequencing. Black pepper associated P. aeruginosa, P. putida and B. megaterium were identified as effective antagonistic endophytes for biological control of Phytophthora foot rot in black pepper. This work provides the first evidence for endophytic bacterial diversity in black pepper stem and roots, with biocontrol potential against P. capsici infection.

  12. Selection, isolation and growth kinetic study of a bacterial consortium obtained from the Potengi mangrove in the presence of crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Costa, C.C.; Vaz, M.R.F.; Santos, E.S.; Macedo, G.R. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia Quimica], E-mail: natcintia@gmail.com; Costa, J.G. da [Universidade Federal do Amazonas (UFAM), Coari, AM (Brazil). Inst. de Saude e Biotecnologia

    2011-10-15

    The selection, isolation and kinetic study of a bacterial consortium obtained from a sample of soil from the Potengi mangrove, located in the city of Natal, Rio Grande do Norte, Brazil, has been carried out using the enrichment culture technique to observe aspects such as the evaluation of main growth parameters. The kinetic study used a rotary incubator shaker at 150rpm, under 30 deg C. The bacterial consortium isolated from the estuary of the Potengi River showed a good acclimation in minimum mineral medium with 1% (v/v) of oil. The cell concentration reached 2.55 g/L at 16h of cultivation and surface tension dropped. The maximum productivity in cells obtained was of 0.3 g/L.h, the specific velocity of growth was of 0.075h{sup -1}, with a generation time (tg) of 9.24h. This study seeks to demonstrate that the consortium can be used as inoculants in biological treatments, capable of reducing the waste's degradation time. (author)

  13. Bacterial Adhesion & Blocking Bacterial Adhesion

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk

    2008-01-01

    reduce or delay bacterial biofilm formation of a range of urinary tract infectious E.coli and Klebsiella isolates. Several other proteinaceous coatings were also found to display anti-adhesive properties, possibly providing a measure for controlling the colonization of implant materials. Several other...... components. These substances may both mediate and stabilize the bacterial biofilm. Finally, several adhesive structures were examined, and a novel physiological biofilm phenotype in E.coli biofilms was characterized, namely cell chain formation. The autotransporter protein, antigen 43, was implicated...

  14. Comparison of SNP-based subtyping workflows for bacterial isolates using WGS data, applied to Salmonella enterica serotype Typhimurium and serotype 1,4,[5],12:i:-

    Science.gov (United States)

    Saltykova, Assia; Wuyts, Véronique; Mattheus, Wesley; Bertrand, Sophie; Roosens, Nancy H. C.; Marchal, Kathleen

    2018-01-01

    Whole genome sequencing represents a promising new technology for subtyping of bacterial pathogens. Besides the technological advances which have pushed the approach forward, the last years have been marked by considerable evolution of the whole genome sequencing data analysis methods. Prior to application of the technology as a routine epidemiological typing tool, however, reliable and efficient data analysis strategies need to be identified among the wide variety of the emerged methodologies. In this work, we have compared three existing SNP-based subtyping workflows using a benchmark dataset of 32 Salmonella enterica subsp. enterica serovar Typhimurium and serovar 1,4,[5],12:i:- isolates including five isolates from a confirmed outbreak and three isolates obtained from the same patient at different time points. The analysis was carried out using the original (high-coverage) and a down-sampled (low-coverage) datasets and two different reference genomes. All three tested workflows, namely CSI Phylogeny-based workflow, CFSAN-based workflow and PHEnix-based workflow, were able to correctly group the confirmed outbreak isolates and isolates from the same patient with all combinations of reference genomes and datasets. However, the workflows differed strongly with respect to the SNP distances between isolates and sensitivity towards sequencing coverage, which could be linked to the specific data analysis strategies used therein. To demonstrate the effect of particular data analysis steps, several modifications of the existing workflows were also tested. This allowed us to propose data analysis schemes most suitable for routine SNP-based subtyping applied to S. Typhimurium and S. 1,4,[5],12:i:-. Results presented in this study illustrate the importance of using correct data analysis strategies and to define benchmark and fine-tune parameters applied within routine data analysis pipelines to obtain optimal results. PMID:29408896

  15. [PHENOTYPICAL CHARACTERISTICS AND GENETICAL DETERMINANTS OF PATHOGENICITY OF STAPHYLOCOCCUS AUREUS, ISOLATED FROM BACTERIAL CARRIERS, RESIDING ON THE TERRITORIES WITH VARIOUS LEVELS OF ANTHROPOGENIC POLLUTION OF AIR ENVIRONMENT].

    Science.gov (United States)

    Utkina, T M; Popova, L P; Kartashova, O L; Khazeeva, G D; Khaliullina, A A

    2015-01-01

    Comparative phenotypical and genetical evaluation of pathogenic potential of Staphylococcus aureus strains, isolated from resident bacterial carriers, residing on the territories with anthropogenic pollution of air environment of varying intensity. S. aureus, isolated 3 times from mucous membrane of the anterior of nose from 210 children, were the object of the study. Anti-carnosine activity and biofilm formation was determined by a photometric method, antibiotics resistance--by a disc diffusion method. lukS, lukF, sec 3, clfA, clfB, agr and mecA gene detection, that are associated with S. aureus, was carried out by PCR. S. aureus strains, isolated from children, residing on the territories with a high level of anthropogenic pollution of air environment, were characterized by antibiotics resistance, higher values of anti-carnosine activity, 2 times more frequently formed biofilms with higher values of the parameter. clfA and clfB genes, that determine colonization of mucous membranes, and agr gene were detected in all the studied S. aureus strains, lukF and sec 3 genes were detected in 20-40% of the strains, isolated from children, residing on both territories. mecA and lukS genetical determinants were not detected. S. aureus, isolated from children, residing on the territories with high levels of anthropogenic pollution of air environment; were characterized by higher values of the studied factors of persistence and stability against antibiotics. Genetical determinants of pathogenicity were not detected in S. aureus, isolated from individuals, residing on both territories.

  16. Stenotrophomonas maltophilia with histopathological features mimicking cutaneous gamma/delta T-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Natalie Kash

    2015-01-01

    Full Text Available We report a case of cutaneous Stenotrophomonas maltophilia infection which presented with clinical and histopathological findings that mimicked a gamma/delta (γδ T-cell lymphoma. In this case, tissue culture of the biopsy specimen was key to determining the diagnosis and allowing appropriate treatment with oral trimethoprim–sulfamethoxazole and topical silvadene. A prompt complete resolution of lesions was observed following antibiotic treatment, with no recurrence of disease over the last 5 years, supporting an infectious rather than malignant etiology. In our patient, radiation therapy was indicated based on the misdiagnosis of γδ T-cell lymphoma, which was supported both clinically and histopathologically. However, tissue culture in this case avoided unnecessary radiation exposure and highlights the role of tissue culture in the evaluation of the biopsy of an undiagnosed cutaneous lesion.

  17. In vitro interaction of Stenotrophomonas maltophilia with human monocyte-derived dendritic cells

    Directory of Open Access Journals (Sweden)

    Emanuela eRoscetto

    2015-07-01

    Full Text Available Stenotrophomonas maltophilia is increasingly identified as an opportunistic pathogen in immunocompromised, cancer and cystic fibrosis (CF patients. Knowledge on innate immune responses to S. maltophilia and its potential modulation is poor. The present work investigated the ability of 12 clinical S. maltophilia strains (5 from CF patients, 7 from non-CF patients and one environmental strain to survive inside human monocyte-derived dendritic cells (DCs. The effects of the bacteria on maturation of and cytokine secretion by DCs were also measured. S. maltophilia strains presented a high degree of heterogeneity in internalization and intracellular replication efficiencies as well as in the ability of S. maltophilia to interfere with normal DCs maturation. By contrast, all S. maltophilia strains were able to activate DCs, as measured by increase in the expression of surface maturation markers and proinflammatory cytokines secretion.

  18. Potential for Combined Biocontrol Activity against Fungal Fish and Plant Pathogens by Bacterial Isolates from a Model Aquaponic System

    Directory of Open Access Journals (Sweden)

    Ivaylo Sirakov

    2016-11-01

    Full Text Available One of the main challenges in aquaponics is disease control. One possible solution for this is biological control with organisms exerting inhibitory effects on fish and plant pathogens. The aim of this study was to examine the potential of isolating microorganisms that exert an inhibitory effect on both plant and fish pathogens from an established aquaponic system. We obtained 924 isolates on selective King’s B agar and 101 isolates on MRS agar from different compartments of a model aquaponic system and tested them for antagonism against the plant pathogen Pythium ultimum and fish pathogen Saprolegnia parasitica. Overall, 42 isolates were able to inhibit both fungi. Although not yet tested in vivo, these findings open new options for the implementation of biological control of diseases in aquaponics, where plants and fish are cultivated in the same water recirculating system.

  19. Isolation and identification of bacterial consortia responsible for degrading oil spills from the coastal area of Yanbu, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Amr Abd-EL Mooti EL Hanafy

    2016-01-01

    Full Text Available Twenty-three crude-oil-degrading bacteria were isolated from oil-contaminated sites near the Red Sea. Based on a high growth rate on crude oil and on hydrocarbon degradation ability, four strains were selected from the 23 isolated strains for further study. These four strains were selected on the basis of dichlorophenolindophenol assay. The nucleotide sequences of the 16S rRNA gene showed that these isolated strains belonged to genus Pseudomonas and Nitratireductor. Among the four isolates, strains S5 (Pseudomonas sp., 95% and 4b (Nitratireductor sp., 70% were the most effective ones in degrading crude oil. Using a spectrophotometer and gas chromatography–mass spectrometry, degradation of more than 90% of the crude oil was observed after two weeks of cultivation in Bushnell–Haas medium. The results showed that these strains have the ability to degrade crude oil and may be used for environmental remediation.

  20. Prevalence and antibiotic sensitivity of Danish versus other European bacterial isolates from intensive care and hematology/oncology units

    DEFF Research Database (Denmark)

    Fomsgaard, A; Høiby, Niels; Friis, H M

    1995-01-01

    The prevalence and antibiotic sensitivity patterns of bacteria collected consecutively from medical and surgical intensive care units (ICUs) and from hematology/oncology units in nine hospitals in Denmark were determined and compared to data collected simultaneously in 12 other European countries...... frequent in other European countries than Denmark. In general the Danish isolates were more sensitive to antibiotics than the European isolates.(ABSTRACT TRUNCATED AT 250 WORDS)...

  1. Prevalence and antibiotic sensitivity of Danish versus other European bacterial isolates from intensive care and hematology/oncology units

    DEFF Research Database (Denmark)

    Fomsgaard, A; Høiby, Niels; Friis, H M

    1995-01-01

    ICUs) or Enterococcus spp. and Klebsiella spp. (from hematology/oncology units), are the most prominent pathogens in these units today. Indicator organisms of antibiotic consumption (Pseudomonas aeruginosa and methicillin-resistant coagulase-negative staphylococci and Staphylococcus aureus) were more......, Escherichia coli was most prevalent in Denmark while coagulase-negative staphylococci were predominant in other countries. Urinary tract isolates were dominated by Escherichia coli in both Denmark and the other countries, but Enterococcus faecalis and Pseudomonas aeruginosa were more frequently isolated...

  2. Isolation and Evaluation of Marine Actinomycetes from Mangrove Forests in South of Iran against Some Human Bacterial Pathogens

    Directory of Open Access Journals (Sweden)

    Farshid Kafilzadeh

    2013-04-01

    Full Text Available Background & Objectives: Recent studies have shown that aquatic actinomycetes can be a source of new biological products such as antibiotics and i n dustrial products. This study was designed to examine the aquatic actinomycetes isolated from mangrove forests in South of Iran and their antibacterial activities against some human pathogens.   Methods: In this study 115 samples were randomly taken from different places of a mangrove forests in South of Iran. Isolation was based on serial dilution of the samples and plating them on starch casein agar medium. Agar well diffusion and disc diffusion assays were used to examine the antibacterial activity of the isolated purified aquatic actinomycetes.   Results: The aquatic actinomycetes were isolated from 83 samples (70%. Of them, 66 (80 percent showed antibacterial activity and 17 (20% could not inhibit the human pathogenic bacteria. The diameter of the inhibitory zones (ZOI ranged from 4 to 11 mm and the biggest zone belonged to B acillus cereus (p≤0.05.   Conclusion: The findings showed that the various and useful aquatic actinomycetes for production of new antibiotic compounds are isolated easily from the mangrove forests in South of Iran. Considering the vast spreading of mangrove forests in South of Iran and the economic and simplicity of isolation of actinomycetes for industrial usage, these source can be an important and new place for research and industry.

  3. Mineralization of ( sup 14 C)hexadecane and ( sup 14 C)phenanthrene in crude oil: Specificity among bacterial isolates

    Energy Technology Data Exchange (ETDEWEB)

    Foght, J.M.; Fedorak, P.M.; Westlake, D.W.S. (Univ. of Alberta, Edmonton, AB (Canada))

    1990-01-01

    Bacteria isolated from freshwater, marine, and estuarine samples were tested for the ability to produce {sup 14}CO{sub 2} from n-(1-{sup 14}C)hexadecane or (9-{sup 14}C)phenanthrene added to Prudhoe Bay crude oil. Of 138 isolates tested, 54 (39%) mineralized the model aliphatic compound hexadecane and 6 (4%) mineralized the model aromatic compound phenanthrene. None mineralized both compounds. There was no apparent correlation between degradative ability and genus or source. Additional hydrocarbon-degrading bacteria from diverse sources were tested and found to mineralize either hexadecane or phenanthrene. Of 61 hexadecane- and 21 phenanthrene-mineralizing bacteria tested, none mineralized both model compounds. Selected isolates and commercially available cultures were tested for mineralization of specific {sup 14}C-labelled mono-, di-, and tri-cyclic aromatics. An apparent hierarchy of degradation was observed: strains mineralizing the mono- and di-cyclic aromatics toluene and napthalene did not mineralize biphenyl or the tricyclic aromatics anthracene and phenanthrene, whereas those strains that mineralized the tricyclic aromatics also mineralized the smaller substrates. Similarly, not all n-alkane-mineralizing isolates tested mineralized the isoprenoid pristane. A combined culture consisting of one aliphatic- and one aromatic-degrading isolate was tested for mineralization of the model compounds and for degradation of other crude oil components by gas chromatography. No synergism or antagonism was observed compared with degradation by the individual isolates. 31 refs., 2 figs., 3 tabs.

  4. In vitro antibacterial activity of venom protein isolated from sea snake Enhydrina schistosa against drugresistant human pathogenic bacterial strains

    Directory of Open Access Journals (Sweden)

    Palani Damotharan

    2015-06-01

    Full Text Available Objective: To evaluate the antibacterial activity of sea snake (Enhydrina schistosa venom protein against drug-resistant human pathogenic bacterial strains. Methods: The venom was collected by milking process from the live specimens of sea snake are using capillary tubes or glass plates. Venom was purified by ion exchange chromatography and it was tested for in-vitro antibacterial activity against 10 drug-resistant human pathogenic bacterial strains using the standard disc diffusion method. Results: The notable antibacterial activity was observed at 150 µg/mL concentration of purified venom and gave its minimum inhibitory concentrations values exhibited between 200-100 µg/mL against all the tested bacterial strains. The maximum zone of inhibition was observed at 16.4 mm against Salmonella boydii and the minimum activity was observed at 7.5 mm against Pseudomonas aeruginosa. After the sodium-dodecyl-sulfate-polyacrylamide gel electrophoresis there were a clear single band was detected in the gel that corresponding to purified venom protein molecular weight of 44 kDa. Conclusions: These results suggested that the sea snake venom might be a feasible source for searching potential antibiotics agents against human pathogenic diseases.

  5. Comparison of bacterial biomass and PRP production between different isolation of Haemophilus influenza type-b (Hib under different culture conditions

    Directory of Open Access Journals (Sweden)

    Hadi, A.

    2011-06-01

    Full Text Available Heamophilus influenzae type-b (Hib is a gram - negative pleomorphic bacterium that causes meningitis infections in children with the age of less than 5 years particularly in two years old infants. In the present study various isolates of Heamophilus influenzae from infants suspected to meningitis were collected, identified, characterized and were used throughout our experiments. Different culture media namely Brain Heart Infusion Broth (BHIB, Tryptic Soy Broth (TSB and GC medium Base (GCB which this medium was modified and prepared in our own laboratory, were compared to determine the highest bacterial yield. All media were added supplements 10mg/ml hemin & 0.01/ml IsovitaleX containing V factor. The bacterial yield for all Hib strains present in our laboratory were measured with an initial inoculums of 104 cfu per ml. The result showed very closed amount of biomass for all isolates however, GCB had slightly higher yield and ultimately we chose this medium for cultivation and extraction of capsular polysaccharide (CPS-b. In our laboratory we have adapted the PRP production according to our technical and instrumental availabilities which exists in our laboratories replacing ultra centrifugation to phenol chloroform to remove contaminants like endotoxin and proteins to the minimum level and also decreased the number of some chemical treatments while some steps were added in purification process. Our study showed although there were not significant differences between the PRP extract of the three isolates with average amount of 108 mg/lit, however, isolate ATCC10210 (ATF2 showed the highest amount with 192mg/lit and the least PRP was produced by isolate H.inf.1, with 16 mg/lit. It seems that the data can be categorized to a normal distribution with the mean of 106.4 and standard deviation of 6.25. This result was confirmed by one sample kolmogorov-Smirnov test, hence the PRP ≥192 mg/lit is statistically significant at a significant level of α =0

  6. Risk factors for surgical site infection following laparotomy: Effect of season and perioperative variables and reporting of bacterial isolates in 287 horses.

    Science.gov (United States)

    Isgren, C M; Salem, S E; Archer, D C; Worsman, F C F; Townsend, N B

    2017-01-01

    Surgical site infection (SSI) is an important cause of post operative morbidity following laparotomy. To investigate risk factors for SSI, including effect of season and surgery performed outside normal working hours, and to report bacterial isolates and antimicrobial resistance patterns. Retrospective cohort study. Data were obtained from horses that had undergone exploratory laparotomy over a 3-year period (2010-2013) in a UK hospital population. SSI was defined as any purulent or serous discharge from the laparotomy incision of >24 h duration that developed during hospitalisation. Multivariable logistic regression was used to identify associations between pre-, intra- and post operative variables and altered likelihood of SSI. Surgical site infection developed in 73/287 (25.4%) horses during hospitalisation. Horses of greater bodyweight (odds ratio [OR] 1.002, 95% confidence interval [CI] 1.0002-1.005, P = 0.03), increased packed cell volume (≥48%) on admission (OR 3.03, 95% CI 1.32-6.94, P = 0.01), small intestinal resection (OR 2.27, 95% CI 1.15-4.46, P = 0.02) and post operative colic (OR 2.86, 95% CI 1.41-5.79, P = 0.003) were significantly associated with increased likelihood of SSI in a multivariable model. SSI was also significantly more likely to occur during winter (OR 3.84, 95% CI 1.38-10.70, P = 0.01) and summer (OR 5.63, 95% CI 2.07-15.3, P = 0.001) months in the model. Three-layer closure of the incision was protective (OR 0.31, 95% CI 0.16-0.58, P<0.001) compared to 2-layer closure. There was no effect of surgery being performed outside normal working hours (P = 0.5). The most common bacterial isolates were Escherichia coli (59.5%), Enterococcus spp. (42.4%) and Staphylococcus spp. (25.4%). Penicillin resistant isolates accounted for 92% (96/104) of isolates while 18% (21/119) of isolates were gentamicin resistant. Laparotomy during winter and summer months was associated with increased likelihood of SSI but there was no effect of surgery

  7. Evaluation of Antimicrobial Activity of Cuminum Cyminum Essential Oil and Extract against Bacterial Strains Isolated from Patients with Symptomatic Urinary Tract Infection

    Directory of Open Access Journals (Sweden)

    Yasaman Saee

    2016-10-01

    Full Text Available Background: Many efforts have been done to find effective agents against resistant pathogens. Cuminum cyminum L. (Cumin is an aromatic plant within the Apiaceae family. It has a variety of purposes and demonstrates antimicrobial and antioxidant properties. This study evaluated the activity of C. cyminum extract and essential oil against bacterial isolates which cause urinary tract infection, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus agalactiae, group A streptococci, Enterococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus and Staphylococcus saprophyticus isolated from patients with urinary tract infection.Materials and Methods: Extract was prepared by maceration and essential oil was prepared by hydrodistillation from C. cyminum seeds. The study population was 95 patients with urinary tract infection without malignant diseases, diabetes and immunosupression. After identification of organism, susceptibility testing was carried out by disc diffusion method and MIC values by broth microdilution testing.Results: C. cyminum essential oil can have a better effect on the gram-negative bacteria causing urinary tract infection than gram-positive bacteria. In addition, C. cyminum extract have good activity against both gram- positive and gram-negative bacteria. Our findings also showed that essential oil and extract of C. cyminum has better antibacterial activity on uropathogen isolates than amoxicillin and the difference was significant (P value<0.05 but the activity is not superior to other antibiotics.Conclusion: These results suggest that the essential oil and extract of C. cyminum seeds might be considered as interesting sources of antibacterial components against uropathogenic bacteria.

  8. Antibacterial agents and heavy metal resistance in Gram-negative bacteria isolated from seawater, shrimp and sediment in Iskenderun Bay, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Matyar, Fatih [Cukurova University, Faculty of Education, Department of Science and Technology Education, 01330 Balcali, Adana (Turkey)], E-mail: fmatyar@cu.edu.tr; Kaya, Aysenur; Dincer, Sadik [Cukurova University, Faculty of Science and Letters, Department of Biology, 01330 Balcali, Adana (Turkey)

    2008-12-15

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 {mu}g/ml to > 3200 {mu}g/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for

  9. Antibacterial agents and heavy metal resistance in Gram-negative bacteria isolated from seawater, shrimp and sediment in Iskenderun Bay, Turkey

    International Nuclear Information System (INIS)

    Matyar, Fatih; Kaya, Aysenur; Dincer, Sadik

    2008-01-01

    The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 μg/ml to > 3200 μg/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for public

  10. Protocol for Evaluating the Permissiveness of Bacterial Communities Toward Conjugal Plasmids by Quantification and Isolation of Transconjugants

    DEFF Research Database (Denmark)

    Klümper, Uli; Dechesne, Arnaud; Smets, Barth F.

    2014-01-01

    The transfer of conjugal plasmids is the main bacterial process of horizontal gene transfer to potentially distantly related bacteria. These extrachromosomal, circular DNA molecules host genes that code for their own replication and transfer to other organisms. Because additional accessory genes...... may encode catabolic pathways, virulence factors, and antibiotic or metal resistances, it is of environmental, evolutionary, and medical relevance to track and monitor the fate of plasmids in mixed microbial community. When assessing the short-term and long-term implications of conjugal plasmid...

  11. In vitro antimicrobial susceptibility of bacterial enteropathogens isolated from international travelers to Mexico, Guatemala, and India from 2006 to 2008.

    Science.gov (United States)

    Ouyang-Latimer, Jeannette; Jafri, Syed; VanTassel, Audrey; Jiang, Zhi-Dong; Gurleen, Kaur; Rodriguez, Savio; Nandy, Ranjan K; Ramamurthy, Thandavaryan; Chatterjee, Santanu; McKenzie, Robin; Steffen, Robert; DuPont, Herbert L

    2011-02-01

    The incidence rates of travelers' diarrhea (TD) have remained high for the last 50 years. More recently, there have been increasing recommendations for self-initiated therapy and use of prophylactic drugs for TD. We last examined the in vitro susceptibilities of commonly used antibiotics against TD pathogens in 1997. We now examine 456 enteropathogens isolated from adult travelers to Mexico, India, and Guatemala with diarrhea acquired between 2006 and 2008 to determine changes in susceptibility against 10 different antimicrobials by the agar dilution method. Traditional antibiotics, such as ampicillin, trimethoprim-sulfamethoxazole, and doxycycline, continue to show high levels of resistance. Current first-line antibiotic agents, including fluoroquinolones and azithromycin, showed significantly higher MICs than in our earlier study, and MIC(90) levels were above the Clinical and Laboratory Standards Institute cutoffs for resistance. There were significant geographical differences in resistance patterns when Central America was compared with India. Entertoxigenic Escherichia coli (ETEC) isolates showed increased resistance to ciprofloxacin (P = 0.023) and levofloxacin (P = 0.0078) in India compared with Central America. Enteroaggregative E. coli (EAEC) isolates from Central America showed increased resistance to nearly all of the antibiotics tested. Compared to MICs of isolates 10 years prior, there were 4- to 10-fold increases in MIC(90) values for ceftriaxone, ciprofloxacin, levofloxacin, and azithromycin for both ETEC and EAEC. There were no significant changes in rifaximin MICs. Rising MICs over time imply the need for continuous surveillance of susceptibility patterns worldwide and geographically specific recommendations in TD therapy.

  12. Detection of antibiotic resistance genes β-lactamics in bacterial strains isolated from Umbilical Cord Blood Units for transplant

    Directory of Open Access Journals (Sweden)

    J.M. Bello-López

    2017-01-01

    Conclusions: The genotype detection encoding antibiotic resistance in isolates of UCBU clearly indicates the potential risk of sepsis difficult to eradicate in the patient, if present in a UCBU available for transplant. Additionally, the existence of these genes reveals horizontal transfer events of genetic material between bacteria. So the importance to realize this studies before transplant.

  13. Complete Genome Sequence of Neisseria meningitidis Serogroup A Strain NMA510612, Isolated from a Patient with Bacterial Meningitis in China

    OpenAIRE

    Zhang, Yan; Yang, Jian; Xu, Li; Zhu, Yafang; Liu, Bo; Shao, Zhujun; Zhang, Xiaobing; Jin, Qi

    2014-01-01

    Serogroup A meningococcal strains have been involved in several pandemics and a series of epidemics worldwide in the past. Determination of the genome sequence of the prevalent genotype strain will help us understand the genetic background of the evolutionary and epidemiological properties of these bacteria. We sequenced the complete genome of Neisseria meningitidis NMA510612, a clinical isolate from a patient with meningococcal meningitis.

  14. Antagonism in vitro of bacterial isolates from comercial and wild strawberry vs. Botrytis cinerea and Rhizopus stolonifer

    Directory of Open Access Journals (Sweden)

    Rosa Isela Plascencia Tenorio

    2012-09-01

    Full Text Available Strawberry is a non-climacteric fruit, with a short postharvest life. The loss of fruit quality may be due, among other factors to damage caused by pathogens. Among the most common fungi are causing gray mold (Botrytis cinerea and white rot (Rhizopus stolonifer two phytopathogenic impact on their growth rate which allows you to colonize the surface of these caused major economic losses. An alternative to control damage in fruit postharvest pathogens usingmicrobial antagonists may be present in the plant or fruit, but at low densities. In this study bacteria were isolated from leaf tissue and wild strawberry fruit (Duchesnea indicates Andr. Fock and comercial strawberry. Those isolates that were selected had the highest percentages of inhibition of mycelial growth of both pathogens in vitro. We isolated a total of 32 strains of which 15 came from wild strawberry and 24 commercial strawberry. Only nine strains were obtained with biocontrol potential for one or both pathogens. The highest percentages of mycelial growth inhibition ranged from 67.1% and 81.7% for Botrytis cinerea and 45.5% to 73.2% for Rhizopus stolonifer. These were obtained from four isolates two of them from wild strawberry and the others from commercial strawberry, all with ability to control both pathogens.

  15. Semi-automated Biopanning of Bacterial Display Libraries for Peptide Affinity Reagent Discovery and Analysis of Resulting Isolates.

    Science.gov (United States)

    Sarkes, Deborah A; Jahnke, Justin P; Stratis-Cullum, Dimitra N

    2017-12-06

    Biopanning bacterial display libraries is a proven technique for peptide affinity reagent discovery for recognition of both biotic and abiotic targets. Peptide affinity reagents can be used for similar applications to antibodies, including sensing and therapeutics, but are more robust and able to perform in more extreme environments. Specific enrichment of peptide capture agents to a protein target of interest is enhanced using semi-automated sorting methods which improve binding and wash steps and therefore decrease the occurrence of false positive binders. A semi-automated sorting method is described herein for use with a commercial automated magnetic-activated cell sorting device with an unconstrained bacterial display sorting library expressing random 15-mer peptides. With slight modifications, these methods are extendable to other automated devices, other sorting libraries, and other organisms. A primary goal of this work is to provide a comprehensive methodology and expound the thought process applied in analyzing and minimizing the resulting pool of candidates. These techniques include analysis of on-cell binding using fluorescence-activated cell sorting (FACS), to assess affinity and specificity during sorting and in comparing individual candidates, and the analysis of peptide sequences to identify trends and consensus sequences for understanding and potentially improving the affinity to and specificity for the target of interest.

  16. Isolation, pathogenicity and characterization of a novel bacterial pathogen Streptococcus uberis from diseased mandarin fish Siniperca chuatsi.

    Science.gov (United States)

    Luo, Xia; Fu, Xiaozhe; Liao, Guoli; Chang, Ouqin; Huang, Zhibin; Li, Ningqiu

    2017-06-01

    In recent years, mandarin fish had a high mortality rate associated with abnormal swimming, exophthalmia, corneal opacity and eye hemorrhage on a fish farm located at Foshan city, Guangdong province, China. Three isolates of Gram-positive, chain-forming cocci were recovered from moribund fish, and designated as SS131025-1, SS131025-2, and SS131025-3. These isolates were identified as Streptococcus uberis according to their morphologic and physio-biochemical characteristics as well as phylogenetic analysis based on their 16S rRNA and GapC gene sequences. The pathogenicity of S. uberis to mandarin fish was determined by challenge experiments. Results of artificial challenge showed S. uberis infected healthy mandarin fish and lead to death by eyeball injection or immersion route, and the LD 50 of SS131025-1 with eyeball injection was 2.0 × 10 6.42  CFU per fish. Moreover extracellular product (ECP) of the isolated S.uberis induced CPB cell apoptosis and cause death of mandarin fish. In addition, these S. uberis strains could also infect tilapia, but not grass carp and crucian carp, and grew in brain-heart infusion broth with an optimal temperature of 37 °C, pH of 7.0, and salinity of 0%. Antibiotic sensitivity testing indicated that these isolates were susceptible to rifampicin and furazolidone but resistant to 20 kinds of antibiotics. Histopathologically, infection with S. uberis could cause serious pathological changes in brain tissues such as vacuoles in matrix, swollen mitochondria with lysis of cristae and disintegration, and lots of coccus was observed both under electron and light microscope. These results shed some light on the pathogenicity of the isolates and how to prevent and control S. uberis infection in mandarin fish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Bioremediation of PCB-contaminated shallow river sediments: The efficacy of biodegradation using individual bacterial strains and their consortia.

    Science.gov (United States)

    Horváthová, Hana; Lászlová, Katarína; Dercová, Katarína

    2018-02-01

    Elimination of dangerous toxic and hydrophobic chlorinated aromatic compounds, mainly PCBs from the environment, is one of the most important aims of the environmental biotechnologies. In this work, biodegradation of an industrial mixture of PCBs (Delor 103, equivalent to Aroclor 1242) was performed using bacterial consortia composed of four bacterial strains isolated from the historically PCB-contaminated sediments and characterized as Achromobacter xylosoxidans, Stenotrophomonas maltophilia, Ochrobactrum anthropi and Rhodococcus ruber. The objective of this research was to determine the biodegradation ability of the individual strains and artificially prepared consortia composed of two or three bacterial strains mentioned above. Based on the growth parameters, six consortia were constructed and inoculated into the historically contaminated sediment samples collected in the efflux canal of Chemko Strážske plant - the former producer of the industrial mixtures of PCBs. The efficacy of the biotreatment, namely bioaugmentation, was evaluated by determination of ecotoxicity of treated and non-treated sediments. The most effective consortia were those containing the strain R. ruber. In the combination with A. xylosoxidans, the biodegradation of the sum of the indicator congeners was 85% and in the combination with S. maltophilia nearly 80%, with inocula applied in the ratio 1:1 in both cases. Consortium containing the strain R. ruber and S. maltophilia showed pronounced degradation of the highly chlorinated PCB congeners. Among the consortia composed of three bacterial strains, only that consisting of O. anthropi, R. ruber and A. xylosoxidans showed higher biodegradation (73%). All created consortia significally reduced the toxicity of the contaminated sediment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. SugE belongs to the small multidrug resistance (SMR) protein family involved in tributyltin (TBT) biodegradation and bioremediation by alkaliphilic Stenotrophomonas chelatiphaga HS2.

    Science.gov (United States)

    Hassan, Hamdy A

    2018-03-01

    Tributyltin (TBT) used in a variety of industrial processes, subsequent discharge into the environment, its fate, toxicity and human exposure are topics of current concern. TBT degradation by alkaliphilic bacteria may be a key factor in the remediation of TBT in high pH contaminated sites. In this study, Stenotrophomonas chelatiphaga HS2 were isolated and identified from TBT contaminated site in Mediterranean Sea. S. chelatiphaga HS2 has vigor capability to transform TBT into dibutyltin and monobutyltin (DBT and MBT) at pH 9 and 7% NaCl (w/v). A gene was amplified and characterized from strain HS2 as SugE protein belongs to SMR protein family, a reverse transcription polymerase chain reaction analysis confirmed that SugE protein involved in the TBT degradation by HS2 strain. TBT bioremediation was investigated in stimulated TBT contaminated sediment samples (pH 9) using S chelatiphaga HS2 in association with E. coli BL21 (DE3)-pET28a(+)-sugE instead of S chelatiphaga HS2 alone reduced significantly the TBT half-life from 12d to 5d, although no TBT degradation appeared using E. coli BL21 (DE3)-pET28a(+)-sugE alone. This finding indicated that SugE gene increased the rate and degraded amount of TBT and is necessary in enhancing TBT bioremediation. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Optimization of Crude Oil and PAHs Degradation by Stenotrophomonas rhizophila KX082814 Strain through Response Surface Methodology Using Box-Behnken Design

    Science.gov (United States)

    Virupakshappa, Praveen Kumar Siddalingappa; Mishra, Gaurav; Mehkri, Mohammed Ameenuddin

    2016-01-01

    The present paper describes the process optimization study for crude oil degradation which is a continuation of our earlier work on hydrocarbon degradation study of the isolate Stenotrophomonas rhizophila (PM-1) with GenBank accession number KX082814. Response Surface Methodology with Box-Behnken Design was used to optimize the process wherein temperature, pH, salinity, and inoculum size (at three levels) were used as independent variables and Total Petroleum Hydrocarbon, Biological Oxygen Demand, and Chemical Oxygen Demand of crude oil and PAHs as dependent variables (response). The statistical analysis, via ANOVA, showed coefficient of determination R 2 as 0.7678 with statistically significant P value 0.0163 fitting in second-order quadratic regression model for crude oil removal. The predicted optimum parameters, namely, temperature, pH, salinity, and inoculum size, were found to be 32.5°C, 9, 12.5, and 12.5 mL, respectively. At this optimum condition, the observed and predicted PAHs and crude oil removal were found to be 71.82% and 79.53% in validation experiments, respectively. The % TPH results correlate with GC/MS studies, BOD, COD, and TPC. The validation of numerical optimization was done through GC/MS studies and % removal of crude oil. PMID:28116165

  20. Copper Enhanced Monooxygenase Activity and FT-IR Spectroscopic Characterisation of Biotransformation Products in Trichloroethylene Degrading Bacterium: Stenotrophomonas maltophilia PM102

    Directory of Open Access Journals (Sweden)

    Piyali Mukherjee

    2013-01-01

    Full Text Available Stenotrophomonas maltophilia PM102 (NCBI GenBank Acc. no. JQ797560 is capable of growth on trichloroethylene as the sole carbon source. In this paper, we report the purification and characterisation of oxygenase present in the PM102 isolate. Enzyme activity was found to be induced 10.3-fold in presence of 0.7 mM copper with a further increment to 14.96-fold in presence of 0.05 mM NADH. Optimum temperature for oxygenase activity was recorded at 36∘C. The reported enzyme was found to have enhanced activity at pH 5 and pH 8, indicating presence of two isoforms. Maximum activity was seen on incubation with benzene compared to other substrates like TCE, chloroform, toluene, hexane, and petroleum benzene. Km and Vmax for benzene were 3.8 mM and 340 U/mg/min and those for TCE were 2.1 mM and 170 U/mg/min. The crude enzyme was partially purified by ammonium sulphate precipitation followed by dialysis. Zymogram analysis revealed two isoforms in the 70% purified enzyme fraction. The activity stain was more prominent when the native gel was incubated in benzene as substrate in comparison to TCE. Crude enzyme and purified enzyme fractions were assayed for TCE degradation by the Fujiwara test. TCE biotransformation products were analysed by FT-IR spectroscopy.

  1. Predictive Studies Suggest that the Risk for the Selection of Antibiotic Resistance by Biocides Is Likely Low in Stenotrophomonas maltophilia

    OpenAIRE

    S?nchez, Mar?a Blanca; Decorosi, Francesca; Viti, Carlo; Oggioni, Marco Rinaldo; Mart?nez, Jos? Luis; Hern?ndez, Alvaro

    2015-01-01

    Biocides are used without restriction for several purposes. As a consequence, large amounts of biocides are released without any control in the environment, a situation that can challenge the microbial population dynamics, including selection of antibiotic resistant bacteria. Previous work has shown that triclosan selects Stenotrophomonas maltophilia antibiotic resistant mutants overexpressing the efflux pump SmeDEF and induces expression of this pump triggering transient low-level resistance...

  2. Simultaneous hydrolysis of carbaryl and chlorpyrifos by Stenotrophomonas sp. strain YC-1 with surface-displayed carbaryl hydrolase

    OpenAIRE

    Yang, Chao; Xu, Xiaoqing; Liu, Yanping; Jiang, Hong; Wu, Yunbo; Xu, Ping; Liu, Ruihua

    2017-01-01

    Many sites are often co-contaminated with multiple pesticides. To date, there are no reports on simultaneous degradation of different classes of pesticides by a natural microorganism. In this work, we aim at constructing a live biocatalyst able to simultaneously hydrolyze carbaryl and chlorpyrifos. For this purpose, carbaryl hydrolase (CH) was displayed on the cell surface of a chlorpyrifos-degrading bacterium Stenotrophomonas sp. strain YC-1 using N- and C-terminal domain of ice nucleation p...

  3. Computed tomography findings of community-acquired Stenotrophomonas Maltophilia pneumonia in an immunocompetent patient: A case report

    International Nuclear Information System (INIS)

    Cha, Yoon Ki; Kim, Jeung Sook; Park, Seong Yeon; Oh, Jin Young; Kwon, Jae Hyun

    2016-01-01

    Stenotrophomonas maltophilia (S. maltophilia) is a rare, but globally emerging gram-negative multiple-drug-resistant organism usually found in a nosocomial setting in immunocompromised patients. To our best knowledge, computed tomography (CT) features of community-acquired S. maltophilia pneumonia have not been previously reported in an immunocompetent patient. Herein, we presented the CT findings of a previous healthy 56-year-old male with S. maltophilia pneumonia

  4. Computed tomography findings of community-acquired Stenotrophomonas Maltophilia pneumonia in an immunocompetent patient: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Yoon Ki; Kim, Jeung Sook; Park, Seong Yeon; Oh, Jin Young; Kwon, Jae Hyun [Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Goyang (Korea, Republic of)

    2016-11-15

    Stenotrophomonas maltophilia (S. maltophilia) is a rare, but globally emerging gram-negative multiple-drug-resistant organism usually found in