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Sample records for twenty bacterial isolates

  1. common bacterial isolates from infected eyes abstract

    African Journals Online (AJOL)

    LIVINGSTON

    The common bacterial isolates and their antibiotics susceptibility were studied in 298 bacterial ... Bacteria were isolated most on the eye infections of the conjunctiva ... practitioners to avoid development of resistance from indiscriminate use.

  2. Insights from twenty years of bacterial genome sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Jun, Se Ran [ORNL; Nookaew, Intawat [ORNL; Leuze, Michael Rex [ORNL; Ahn, Tae-Hyuk [ORNL; Karpinets, Tatiana V [ORNL; Lund, Ole [Technical University of Denmark; Kora, Guruprasad H [ORNL; Wassenaar, Trudy [Molecular Microbiology & Genomics Consultants, Zotzenheim, Germany; Poudel, Suresh [ORNL; Ussery, David W [ORNL

    2015-01-01

    Since the first two complete bacterial genome sequences were published in 1995, the science of bacteria has dramatically changed. Using third-generation DNA sequencing, it is possible to completely sequence a bacterial genome in a few hours and identify some types of methylation sites along the genome as well. Sequencing of bacterial genome sequences is now a standard procedure, and the information from tens of thousands of bacterial genomes has had a major impact on our views of the bacterial world. In this review, we explore a series of questions to highlight some insights that comparative genomics has produced. To date, there are genome sequences available from 50 different bacterial phyla and 11 different archaeal phyla. However, the distribution is quite skewed towards a few phyla that contain model organisms. But the breadth is continuing to improve, with projects dedicated to filling in less characterized taxonomic groups. The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system provides bacteria with immunity against viruses, which outnumber bacteria by tenfold. How fast can we go? Second-generation sequencing has produced a large number of draft genomes (close to 90 % of bacterial genomes in GenBank are currently not complete); third-generation sequencing can potentially produce a finished genome in a few hours, and at the same time provide methlylation sites along the entire chromosome. The diversity of bacterial communities is extensive as is evident from the genome sequences available from 50 different bacterial phyla and 11 different archaeal phyla. Genome sequencing can help in classifying an organism, and in the case where multiple genomes of the same species are available, it is possible to calculate the pan- and core genomes; comparison of more than 2000 Escherichia coli genomes finds an E. coli core genome of about 3100 gene families and a total of about 89,000 different gene families. Why do we care about bacterial genome

  3. Bacterial isolates degrading aliphatic polycarbonates.

    Science.gov (United States)

    Suyama, T; Hosoya, H; Tokiwa, Y

    1998-04-15

    Bacteria that degrade an aliphatic polycarbonate, poly(hexamethylene carbonate), were isolated from river water in Ibaraki. Prefecture, Japan, after enrichment in liquid medium containing poly(hexamethylene carbonate) suspensions as carbon source, and dilution to single cells. Four of the strains, 35L, WFF52, 61A and 61B2, degraded poly(hexamethylene carbonate) on agar plate containing suspended poly(hexamethylene carbonate). Degradation of poly(hexamethylene carbonate) was confirmed by gel permeation chromatography. Besides poly(hexamethylene carbonate), the strains were found to degrade poly(tetramethylene carbonate). The strains were characterized morphologically, physiologically, and by 16S rDNA sequence analysis. Strains 35L and WFF52 were tentatively identified as Pseudomonas sp. and Variovorax sp., respectively, while strains 61A and 61B2 constitute an unidentified branch within the beta subclass of the Proteobacteria.

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

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    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.

  5. 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.

  6. ANTIMICROBIAL ACTIVITY OF LACTIC ACID BACTERIAL ISOLATES

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    Utkarsha S. Shivsharan

    2013-08-01

    Full Text Available Micro-organisms have tendency to produce antimicrobial substances which show biological activity against other kind of micro-organisms. This phenomenon of bacterial antagonism is observed in lactic acid bacteria with competitive advantages. The lactic acid bacteria are commonly present in many fermented products, fruits and milk products. The variety of antimicrobial substances produced by lactic acid bacteria showing good inhibition capacity include production of lactic acid, acetic acid, hydrogen peroxide, carbon dioxide, diacetyl and bacteriocin. Bacteriocins produced by lactic acid bacteria are the subject of intense research because of their antimicrobial activity against food born bacteria such as Listeria monocytogenes, staphylococcus aureus, Bacillus cereus, Clostridium botulinum and several others .Bacteriocins may be bacteriostatic or bactericidal with narrow or broad range of activity. The main of the study was to study the antimicrobial activity of such lactic acid bacterial isolates.

  7. 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

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

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    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.

  9. 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

  10. Bacterial Biodegradation of Crude Oil Using Local Isolates

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    Raed S. Al-Wasify

    2014-01-01

    Full Text Available An experimental study was undertaken to assess the efficiency of Pseudomonas aeruginosa, Bacillus subtilis, and Acinetobacter lwoffi isolated from petroleum contaminated water and soil samples to degrade crude oil, separately and in a mixed bacterial consortium. Capillary gas chromatography was used for testing the effect of those bacterial species on the biodegradation of crude oil. Individual bacterial cultures showed less growth and degradation than did the mixed bacterial consortium. At temperature 22°C, the mixed bacterial consortium degraded a maximum of 88.5% of Egyptian crude oil after 28 days of incubation. This was followed by 77.8% by Pseudomonas aeruginosa, 76.7% by Bacillus subtilis, and 74.3% by Acinetobacter lwoffi. The results demonstrated that the selected bacterial isolates could be effective in biodegradation of oil spills individually and showed better biodegradation abilities when they are used together in mixed consortium.

  11. Isolation and characterization of bacterial endophytes of Chelidonium majus L.

    Science.gov (United States)

    Goryluk, Agata; Rekosz-Burlaga, Hanna; Błaszczyk, Mieczysław

    2009-01-01

    The aim of this study was to isolate and identify endophytic bacteria from stems of Chelidonium majus L. (greater celandine) and to evaluate their antifungal properties. In total, 34 bacterial endophyte strains were isolated. The fungistatic effects of these bacteria on the growth of five moulds (Alternaria alternata, Chaetonium sp., Paecilomyces variotti, Byssochlamys fulva, Aureobasidium pullulans) and one species of black yeast (Exophiala mesophila) were tested. The majority of the bacterial isolates were found to inhibit the growth of fungi and those with the strongest antifungal properties were further characterized. Of the twelve isolates examined, 11 were species of Bacillus thuringiensis and one was Bacillus amyloliquefaciens.

  12. AEROBIC BACTERIAL ISOLATES FROM INFECTED WOUNDS

    African Journals Online (AJOL)

    boaz

    Sciences, University of Benin Teaching Hospital, P.M.B. 1111, Benin City, Edo State, Nigeria. ... Methods:A total of 207 wound specimens collected from patients attending the University of Benin ..... of bacterial pathogens in burn wound.

  13. Antibacterial Activity of Twenty Iranian Plant Extracts Against Clinical Isolates of Helicobacter pylori

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    Farahnaz Nariman

    2009-06-01

    Full Text Available Objective(sDue to increasing emergence of drug-resistance in Helicobacter pylori isolates, traditional plants arepotentially valuable sources of novel anti-H. pylori agents. In this research, anti-H. pylori activity of theorganic extracts of twenty native Iranian plants was determined against ten clinical isolates of H. pylori.Materials and MethodsDisc diffusion was used to determine the biological activity of 20 plant extracts as well as 8 antibioticscommonly used to treat H. pylori infections. Minimum inhibitory concentrations were also measured by tubeand agar dilution methods for the biologically active plant extracts.ResultsOf the twenty plant extracts analyzed, sixteen exhibited good anti-H. pylori activity, using disc diffusion.The ten most active extracts were Carum bulbocastanum, Carum carvi, Mentha longifolia, Saliva limbata,Saliva sclarea, Ziziphora clinopodioides, Thymus caramanicus, Glycyrrhiza glabra, Xanthium brasilicumand Trachyspermum copticum. Minimum inhibitory concentrations measured for the 10 biologically activeplant extracts were within the range of 31.25 to 500 μg/ml.ConclusionAmong the ten plant extracts effective against H. pylori clinical isolates, Carum carvi, Xanthium brasilicumand Trachyspermum copticum showed the highest activity.Keywords: Anti-Helicobacter pylori, Iranian plants, Organic extracts

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

    African Journals Online (AJOL)

    Studies on hydrocarbon degradation by the bacterial isolate ... Journal Home > Vol 4, No 3 (2015) > ... The degradation of 2 % heavy crude oil and other PAHs from the isolate PM-1 was assessed ... Algeria (5); Benin (2); Botswana (3); Burkina Faso (3); Cameroon (8); Congo, Republic (1); Côte d'Ivoire (4); Egypt, Arab Rep.

  15. Isolation of bacterial endophytes from germinated maize kernels.

    Science.gov (United States)

    Rijavec, Tomaz; Lapanje, Ales; Dermastia, Marina; Rupnik, Maja

    2007-06-01

    The germination of surface-sterilized maize kernels under aseptic conditions proved to be a suitable method for isolation of kernel-associated bacterial endophytes. Bacterial strains identified by partial 16S rRNA gene sequencing as Pantoea sp., Microbacterium sp., Frigoribacterium sp., Bacillus sp., Paenibacillus sp., and Sphingomonas sp. were isolated from kernels of 4 different maize cultivars. Genus Pantoea was associated with a specific maize cultivar. The kernels of this cultivar were often overgrown with the fungus Lecanicillium aphanocladii; however, those exhibiting Pantoea growth were never colonized with it. Furthermore, the isolated bacterium strain inhibited fungal growth in vitro.

  16. Conjunctival sac bacterial flora isolated prior to cataract surgery

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    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

  17. Chitinolytic bactery activity isolated from the mud fields

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    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.

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

    OpenAIRE

    Shahid Mahmood; Muhammad Arshad; Azeem Khalid; Zilli Huma Nazli; Tariq Mahmood

    2011-01-01

    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...

  19. The Prevalence and Antimicrobial Susceptibility of Bacterial Uropathogens Isolated from Pediatric Patients

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    R Ranjbar

    2009-06-01

    Full Text Available "nBackground: Urinary tract infection (UTI is considered as the most common bacterial infectious disease seen among the pediatric patients. The aim of this study was to investigate the prevalence and antimicrobial susceptibility of bacterial uropathogens isolated from the pediatric patients with urinary tract infections."nMethods: This descriptive study was conducted in Children Medial Center, Tehran, Iran from March 2006 to Feb 2007. Clean-catch midstream urine specimens were obtained from the patients and cultured on the appropriate bacteriological media. Bacterial isolates were identified by standard biochemical and serological tests. Antimicrobial susceptibility testing was performed according to CLSI guidelines."nResults: From 14199 urine specimens, 16.2% had positive results for bacterial cultures. Nine hundred twenty one strains were identified as Escherichia coli; 412 as Klebsiella spp., 285 as Coagulase negative Staphylocococci, 202 as Enterococcus spp., 158 as Pseudomonas spp., and 83 as Staphylococcus aureus. E. coli isolates showed high resistance to carbenicillin (68%, ampicillin (96%, trimethoprim-sulfomethoxazol (70% and kanamycin (65%. More than 30% of isolates of Klebsiella spp., Pseudomonas spp. and Enterobacter spp. have shown high degree of resistance to commonly used antibiotics."nConclusion: Our findings reinforce the need for ongoing investigation to show trends in antibiotic resistance, which can help to prescribing of antibiotics in clinics.

  20. 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

  1. Antibiogram of bacterial species isolated from canine pyometra

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    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

  2. Isolation of biologically active nanomaterial (inclusion bodies from bacterial cells

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    Peternel Špela

    2010-09-01

    Full Text Available Abstract Background In recent years bacterial inclusion bodies (IBs were recognised as highly pure deposits of active proteins inside bacterial cells. Such active nanoparticles are very interesting for further downstream protein isolation, as well as for many other applications in nanomedicine, cosmetic, chemical and pharmaceutical industry. To prepare large quantities of a high quality product, the whole bioprocess has to be optimised. This includes not only the cultivation of the bacterial culture, but also the isolation step itself, which can be of critical importance for the production process. To determine the most appropriate method for the isolation of biologically active nanoparticles, three methods for bacterial cell disruption were analyzed. Results In this study, enzymatic lysis and two mechanical methods, high-pressure homogenization and sonication, were compared. During enzymatic lysis the enzyme lysozyme was found to attach to the surface of IBs, and it could not be removed by simple washing. As this represents an additional impurity in the engineered nanoparticles, we concluded that enzymatic lysis is not the most suitable method for IBs isolation. During sonication proteins are released (lost from the surface of IBs and thus the surface of IBs appears more porous when compared to the other two methods. We also found that the acoustic output power needed to isolate the IBs from bacterial cells actually damages proteins structures, thereby causing a reduction in biological activity. High-pressure homogenization also caused some damage to IBs, however the protein loss from the IBs was negligible. Furthermore, homogenization had no side-effects on protein biological activity. Conclusions The study shows that among the three methods tested, homogenization is the most appropriate method for the isolation of active nanoparticles from bacterial cells.

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

    African Journals Online (AJOL)

    Bacterial Profile and Antimicrobial Susceptibility Pattern of Isolates Among Burn Patients at ... Blood specimen and wound swab were collected from burn patients and were cultured by conventional method. ... of bacteremia like prior antibiotic use and total body surface area burn were also determined. ... Article Metrics.

  4. Isolation of polyvinyl chloride degrading bacterial strains from ...

    African Journals Online (AJOL)

    Isolation of polyvinyl chloride degrading bacterial strains from environmental samples using enrichment culture technique. ... by their ability to release chloride from PVC polymer, increase their cell density in test media, carbon dioxide production and growth on the surface of PVC film in plate assay. ... Article Metrics.

  5. 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...

  6. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

    Science.gov (United States)

    Swift, S.; Dean, S. J.; Ormonde, S. E.

    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. PMID:27213052

  7. Spectrum and Sensitivity of Bacterial Keratitis Isolates in Auckland

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    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.

  8. 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.

  9. Plasmid profiling of bacterial isolates from confined environments

    Science.gov (United States)

    van Houdt, Rob; Provoost, Ann; Coninx, Ilse; Leys, Natalie; Mergeay, Max

    Plasmid profiling of bacterial isolates from confined environments R. Van Houdt, I. Coninx, A. Provoost, N. Leys, and M. Mergeay Expertise group for Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK•CEN), Boeretang 200, B-2400 Mol, Belgium. Human exploration of extreme and isolated hostile environments such as space requires special confined small volume habitats to protect and house the crew. However, human confinement in such small volume habitats has restrictions on waste disposal and personal hygiene and inevitably generates a particular community of microorganisms within the habitat. These microorganisms are mainly originating from the crew (skin, mucous membranes, upper respiratory tract, mouth, and gastrointestinal tract) but also include the residing environmental microorganisms. Earth-based confined habitats such as the Antarctic Research Station Concordia are used as test beds for long-duration spaceflights to study the physiologic and psychological adaptation to isolated environments. The dynamics of the environmental microbial population in such a test bed could render additional insights in assessing the potential health risks in long-duration space missions. Not only total bacterial contamination levels are important, but it is essential to identify also the predominant microbial taxa and their mobile genetic elements (MGE). These MGEs could be exchanged between bacteria by horizontal gene transfer and may alter the pathogenic potential since they often carry antibiotic resistance or more in general adaptation-enhancing traits. In this study several bacterial strains isolated in the Concordia research station were examined for their plasmid content. An optimized protocol for extraction of large plasmids showed the present of at least one plasmid in 50% of the strains. For all strains the minimal inhibitory concentration of a range of antibiotics was determined indicating resistance to

  10. Isolation of cell-free bacterial inclusion bodies

    Directory of Open Access Journals (Sweden)

    Rodríguez-Carmona Escarlata

    2010-09-01

    Full Text Available Abstract Background 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. Results 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. Conclusions The application of the developed protocol allows obtaining bacterial free inclusion bodies suitable for use in mammalian cell cultures and other biological interfaces.

  11. 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.

  12. 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

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

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    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.

  14. Degradation and mineralization of atrazine by a soil bacterial isolate.

    OpenAIRE

    Radosevich, M.; Traina, S.J.; Hao, Y. L.; Tuovinen, O H

    1995-01-01

    An atrazine-degrading bacterial culture was isolated from an agricultural soil previously impacted by herbicide spills. The organism was capable of using atrazine under aerobic conditions as the sole source of C and N. Cyanuric acid could replace atrazine as the sole source of N, indicating that the organism was capable of ring cleavage. Ring cleavage was confirmed in 14CO2 evolution experiments with [U-14C-ring]atrazine. Between 40 and 50% of ring-14C was mineralized to 14CO2. [14C]biuret an...

  15. 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.

  16. Twenty-One Genome Sequences from Pseudomonas Species and 19 Genome Sequences from Diverse Bacteria Isolated from the Rhizosphere and Endosphere of Populus deltoides

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Steven D [ORNL; Utturkar, Sagar M [ORNL; Klingeman, Dawn Marie [ORNL; Johnson, Courtney M [ORNL; Martin, Stanton [ORNL; Land, Miriam L [ORNL; Lu, Tse-Yuan [ORNL; Schadt, Christopher Warren [ORNL; Doktycz, Mitchel John [ORNL; Pelletier, Dale A [ORNL

    2012-01-01

    To aid in the investigation of the Populus deltoides microbiome we generated draft genome sequences for twenty one Pseudomonas and twenty one other diverse bacteria isolated from Populus deltoides roots. Genome sequences for isolates similar to Acidovorax, Bradyrhizobium, Brevibacillus, Burkholderia, Caulobacter, Chryseobacterium, Flavobacterium, Herbaspirillum, Novosphingobium, Pantoea, Phyllobacterium, Polaromonas, Rhizobium, Sphingobium and Variovorax were generated.

  17. Bioremediation Potential of Bacterial Isolates for Municipal Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    Nilesh A. Sonune

    2015-08-01

    Full Text Available The potential of bacteria for the treatment of municipal wastewater was investigated in present study. Total eight bacterial isolates were used for this study that showed growth on wastewater agar medium. These isolates were identified on the basis of morphological and biochemical test and identified as Bacillus licheniformis NW16, Pseudomonas aeruginosa NS19, Pseudomonas sp. NS20, Planococcus salinarum NS23, Stenotrophomonas maltophilia NS21, Paenibacillus sp. NW9, Paenibacillus borealis NS3 and Aeromonas hydrophilia NS17. The B. licheniformis NW16 showed highest potential to reduce all parameter under study than other isolates except Ammonical nitrogen. B. licheniformis NW16 and Aeromonas hydrophilia NS17 showed maximum reduction (42.86% in BOD each. B. licheniformis NW16 and Paenibacillus sp. NW9 showed 82.76% and 81.61% reduction in COD respectively. B. licheniformis NW16, P. salinarum NS23 and Aeromonas hydrophilia NS17 showed reduction in nitrate ranging from 17.36%-63.64%. All the isolates have potential to reduced phosphate from 17.55% -72.3%. B. licheniformis NW16, Ps. aeruginosa NS19, Pseudomonas sp. NS20, Paenibacillus sp. NW9 and Aeromonas hydrophilia NS17 showed reduction in TSS ranging from 42.69%-79.94%. B. licheniformis NW16, Ps. aeruginosa NS19, Pseudomonas sp. NS20, S. maltophilia NS21 and Paenibacillus sp. NW9 showed reduction in TDS ranging from 14%-81.4%.

  18. Differential effect of three polyunsaturated aldehydes on marine bacterial isolates.

    Science.gov (United States)

    Ribalet, Francois; Intertaglia, Laurent; Lebaron, Philippe; Casotti, Raffaella

    2008-01-31

    Bioactive polyunsaturated aldehydes (PUAs) are produced by several marine phytoplankton (mainly diatoms) and have been shown to have a detrimental effect on a wide variety of organisms, including phytoplankton and invertebrates. However, their potential impact on marine bacteria has been largely neglected. We assess here the effect of three PUAs produced by marine diatoms: 2E,4E-decadienal, 2E,4E-octadienal and 2E,4E-heptadienal, on the growth of 33 marine bacterial strains, including 16 strains isolated during a bloom of the PUA-producing diatom Skeletonema marinoi in the Northern Adriatic Sea. A concentration-dependent growth reduction was observed for 19 bacterial strains at concentrations ranging from 3 to 145 micromolL(-1). Surprisingly, Eudora adriatica strain MOLA358 (Flavobacteriaceae) and Alteromonas hispanica strain MOLA151 (Alteromonadaceae) showed growth stimulation upon exposure to PUAs at concentrations between 13 and 18 micromolL(-1). The remaining 12 strains were unaffected by even very high PUA concentrations. Strains isolated during the diatom bloom showed remarkable resistance to PUA exposures, with only two out of 16 strains showing growth inhibition at PUA concentrations below 106, 130, and 145 micromolL(-1) for 2E,4E-decadienal, 2E,4E-octadienal and 2E,4E-heptadienal, respectively. No correlation between taxonomical position and sensitivity to PUA was observed. Considering that many bacteria thrive in close vicinity of diatom cells, it is likely that these compounds may shape the structure of associated bacterial communities by representing a selection force. This is even more relevant during the final stages of blooms, when senescence and nutrient limitation increase the potential production and release of aldehydes.

  19. 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.

  20. Antibiogram study of aerobic bacterial isolates from uropathogens

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    Mallikarjuna Reddy C, Himabindu M, Maity Soumendranath, Kanta RC, Kapur Indu

    2014-04-01

    Full Text Available Background: Bacteria are capable of invading and infecting humans, leading to disease and sometimes death. Systems and tissues in human body are vulnerable to different organisms. Infection pattern is likely to differ by geographical regions. Aim: This study was aimed to isolate and identify the type of aerobic bacteria causing Urinary Tract Infections (UTI in different age groups and sexes, and also in some predisposing conditions. Their antibiogram also was done. Materials and Methods: Midstream urine sample collected aseptically from 276 patients were subjected for isolation and identification of aerobic bacteria by standard technique and subsequently antibiogram was done by Kirby –Bayer Method. Both sexes of patients with an age range of 10-70 years and patients with diabetes (22, hypertension (8 and anemia (8 were also included in the study. Results: Escherichia coli was the predominant organism(50% among other isolates – Klebsiella species (27.3%, Proteus species(7.14%, Staphylococcus saprophyticus (5.95%, Staphylococcus aureus (3.57%, Enterococci (3.57%, Pseudomonas species(2.38%. UTI was more common among patients of 60 and more years of age; however, incidence was more in female patients (36.2 – 38.5% compared with male patients (25-30%. Anemia, Diabetes and Hypertension conditions were found to predispose UTI. Aminoglycosides and Quinolones were found to be more effective against the isolates. Conclusion: The present study reveals in spite of the topographical diversity, the infecting bacterial isolates from this area were found to be the same as from any other part of India.

  1. Isolation and Characterization of Nickel Uptake by Nickel Resistant Bacterial Isolate (NiRBI)

    Institute of Scientific and Technical Information of China (English)

    JAGDISH S PATEL; PRERNA C PATEL; KIRAN KALIA

    2006-01-01

    Bioremediation technology has gained importance because microbes could be the convenient source of bio-absorption/bioaccumulation of metals from effluent streams. Methods The nickel-resistant bacterial isolates (NiRBI)were selected from various bacterial isolates from industrial effluent and grown in nutrient broth containing different concentrations of nickel sulfate (0.3-3.0 mmol/L) and their capability of accumulating metal from the medium. Results Well-defined growth of NiRBI was observed in the medium containing up to 2.5 mmol/L of nickel. The isolate was identified using 16S rRNA and closely related to Pseudomonas fragi. Maximum accumulation of nickel (0.59 mg/g dry weight of bacterial cells) was observed when NiRBI was grown in media containing 2 mmol/L of nickel. The protein profile of the NiRBI cellular extract by SDS-PAGE showed two metal stress-induced proteins of molecular weight 48 KD and 18 KD with a simultaneous down regulation of four proteins of 46.7 KD, 42.2 KD, 19.7 KD, and 4.0 KD. Conclusion 48 KD and 18 KD proteins play a role in metal resistance mechanism by NiRBI.

  2. Aerobic cyanide degradation by bacterial isolates from cassava factory wastewater

    Directory of Open Access Journals (Sweden)

    Sujatha Kandasamy

    2015-09-01

    Full Text Available Ten bacterial strains that utilize cyanide (CN as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM and glucose (0.2% w/v. The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters.

  3. Aerobic cyanide degradation by bacterial isolates from cassava factory wastewater.

    Science.gov (United States)

    Kandasamy, Sujatha; Dananjeyan, Balachandar; Krishnamurthy, Kumar; Benckiser, Gero

    2015-01-01

    Ten bacterial strains that utilize cyanide (CN) as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM) and glucose (0.2% w/v). The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters.

  4. 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.

  5. Nontuberculous Mycobacteria Isolation from Clinical and Environmental Samples in Iran: Twenty Years of Surveillance

    Directory of Open Access Journals (Sweden)

    Ali Akbar Velayati

    2015-01-01

    Full Text Available Nontuberculous mycobacteria (NTM are opportunistic pathogens that are widely distributed in the environment. There is a lack of data on species distribution of these organisms from Iran. This study consists of a review of NTM articles published in Iran between the years 1992 and 2014. In this review, 20 articles and 14 case reports were identified. Among the 20 articles, 13 (65% studies focused on NTM isolates from clinical specimens, 6 (30% studies examined NTM isolates from environmental samples, and one (5% article included both clinical and environmental isolates. M. fortuitum (229/997; 23% was recorded as the most prevalent and rapid growing mycobacteria (RGM species in both clinical (28% and environmental (19% isolated samples (P < 0.05. Among slow growing mycobacteria (SGM, M. simiae (103/494; 21% demonstrated a higher frequency in clinical samples whereas in environmental samples it was M. flavescens (44/503; 9%. These data represent information from 14 provinces out of 31 provinces of Iran. No information is available in current published data on clinical or environmental NTM from the remaining 17 provinces in Iran. These results emphasize the potential importance of NTM as well as the underestimation of NTM frequency in Iran. NTM is an important clinical problem associated with significant morbidity and mortality in Iran. Continued research is needed from both clinical and environmental sources to help clinicians and researchers better understand and address NTM treatment and prevention.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

  8. Plutonium interaction with a bacterial strain isolated from the waste isolation pilot plant (WIPP) environment

    Energy Technology Data Exchange (ETDEWEB)

    Strietelmeier, B.A.; Kraus, S.M.; Leonard, P.A.; Triay, I.R. [Los Alamos National Lab., NM (United States)] [and others

    1996-12-31

    This work was conducted as part of a series of experiments to determine the association and interaction of various actinides with bacteria isolated from the WIPP site. The majority of bacteria that exist at the site are expected to be halophiles, or extreme halophiles, due to the high concentration of salt minerals at the location. Experiments were conducted to determine the toxicity of plutonium-n-239, neptunium-237 and americium-243 to several species of these halophiles and the results were reported elsewhere. As an extension of these experiments, we report an investigation of the type of association that occurs between {sup 239}Pu and the isolate WIPP-1A, isolated by staff at Brookhaven National Laboratory, when grown in a high-salt, defined medium. Using scanning electron microscopy (SEM) techniques, we demonstrate a surface association of the {sup 239}Pu with the bacterial cells.

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

    OpenAIRE

    Eslami; Karimiravesh; Taheri; Azargashb

    2014-01-01

    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. ...

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

    OpenAIRE

    Gita Eslami; Sudabeh Taheri; Eznollah Azargashb; raheleh karimiravesh

    2014-01-01

    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 di...

  11. Isolation of bacterial strains from bovine fecal microflora capable of degradation of ceftiofur.

    Science.gov (United States)

    Rafii, Fatemeh; Williams, Anna J; Park, Miseon; Sims, Lillie M; Heinze, Thomas M; Cerniglia, Carl E; Sutherland, John B

    2009-10-20

    Ceftiofur, a third-generation cephalosporin used to treat bacterial infections in animals, is degraded in bovine feces but the specific bacteria involved are unknown. To find the bacteria involved in ceftiofur metabolism, the bovine fecal microflora was screened. Twenty-one nonidentical strains of bovine fecal bacteria were isolated on media containing 1-32 microg ml(-1) of ceftiofur. The cultures were incubated with 5 microg ml(-1) ceftiofur for different times, then centrifuged and analyzed by high-performance liquid chromatography. Three strains of Bacillus spp., two strains of Roseomonas spp., and one strain of Azospirillum sp. metabolized 5 microg ml(-1) ceftiofur in broth cultures in less than 24h; ten other strains of Roseomonas and one strain of Bacillus pumilus had metabolized it by 120 h. After the ceftiofur had been metabolized by these bacteria, the filter-sterilized supernatants of centrifuged cultures no longer inhibited the growth of a ceftiofur-sensitive strain of Kocuria rhizophila, which indicated that ceftiofur had been transformed to compounds without bactericidal activity. Each isolate was also found to be able to grow in the presence of other beta-lactams, and a nitrocefin assay showed beta-lactamase activity in the 17 strains that metabolized ceftiofur. The results show that some beta-lactamase-producing bacteria from the bovine fecal microflora are capable of transforming ceftiofur to metabolites lacking bactericidal activity.

  12. Characterization of rumen bacterial strains isolated from enrichments of rumen content in the presence of propolis.

    Science.gov (United States)

    de Aguiar, Sílvia Cristina; Zeoula, Lucia Maria; do Prado, Odimari Pricila Pires; Arcuri, Pedro Braga; Forano, Evelyne

    2014-11-01

    Propolis presents many biological properties, including antibacterial activities, and has been proposed as an additive in ruminant nutrition. Twenty bacterial strains, previously isolated from enrichments of Brazilian cow rumen contents in the presence of different propolis extracts (LLOS), were characterized using phenotyping and 16S rRNA identification. Seven strains were assigned to Streptococcus sp., most likely S. bovis, and were all degrading starch. One amylolytic lactate-utilizing strain of Selenomonas ruminantium was also found. Two strains of Clostridium bifermentans were identified and showed proteolytic activity. Two strains were assigned to Mitsuokella jalaludinii and were saccharolytic. One strain belonged to a Bacillus species and seven strains were affiliated with Escherichia coli. All of the 20 strains were able to use many sugars, but none of them were able to degrade the polysaccharides carboxymethylcellulose and xylans. The effect of three propolis extracts (LLOS B1, C1 and C3) was tested on the in vitro growth of four representative isolates of S. bovis, E. coli, M. jalaludinii and C. bifermentans. The growth of S. bovis, E. coli and M. jalaludinii was not affected by the three propolis extracts at 1 mg ml(-1). C. bifermentans growth was completely inhibited at this LLOS concentration, but this bacterium was partially resistant at lower concentrations. LLOS C3, with the lower concentration of phenolic compounds, was a little less inhibitory than B1 and C1 on this strain.

  13. Isolation and characterization of organic-sulfur degradation bacterial strain

    Institute of Scientific and Technical Information of China (English)

    YANG Yu; DIAO Meng-xue; SHI Wu-yang; LI Li; DAI Qin-yun; QIU Guan-zhou

    2007-01-01

    A bacterial strain that was capable of degrading organic sulfur (dibenzothiophene) was isolated by enrichment techniques from the petroleum-contaminated soil collected from Zhongyuan Oil Field. The strain is named ZYX and is gram-positive.This strain undergoes bacilus-coccus morphological change, and forms yellow-pigment glossy circular colonies with 1.5 mm in diameter on average after 2 d incubation on Luria-Bertani(LB) plates. The full-length of 16S rDNA sequence of strain ZYX was determined and analyzed. Strain ZYX is found most relative with the genus of Arthrobacter. The similarity values between ZYX and Arthrobacter sp. P2 is 99.53%. The main morphological, biochemical and physiological features of strain ZYX accord with those of Arthrobacter. It is found that the optimal initial pH for growth is about 7.0, and the optimal concentration of dibenzothiophene(DBT)for growth is 0.10 g/L. Additionally, the results show that the best carbon source and nitrogen source are glycerol and glutamine,respectively.

  14. Decolorization of the textile dyes by newly isolated bacterial strains.

    Science.gov (United States)

    Chen, Kuo-Cheng; Wu, Jane-Yii; Liou, Dar-Jen; Hwang, Sz-Chwun John

    2003-02-27

    Six bacterial strains with the capability of degrading textile dyes were isolated from sludge samples and mud lakes. Aeromonas hydrophila was selected and identified because it exhibited the greatest color removal from various dyes. Although A. hydrophila displayed good growth in aerobic or agitation culture (AGI culture), color removal was the best in anoxic or anaerobic culture (ANA culture). For color removal, the most suitable pH and temperature were pH 5.5-10.0 and 20-35 degrees C under anoxic culture (ANO culture). More than 90% of RED RBN was reduced in color within 8 days at a dye concentration of 3,000 mg l(-1). This strain could also decolorize the media containing a mixture of dyes within 2 days of incubation. Nitrogen sources such as yeast extract or peptone could enhance strongly the decolorization efficiency. In contrast to a nitrogen source, glucose inhibited decolorization activity because the consumed glucose was converted to organic acids that might decrease the pH of the culture medium, thus inhibiting the cell growth and decolorization activity. Decolorization appeared to proceed primarily by biological degradation.

  15. Kinetics of zinc toxicity to environmental bacterial isolates

    Directory of Open Access Journals (Sweden)

    Christian Okechukwu Nweke

    2009-12-01

    Full Text Available Toxicity of zinc to Pseudomonas, Escherichia, Proteus, Bacillus and Arthrobacter species isolated from a tropical river and petroleum refinery effluent was assessed using TTC-dehydrogenase activity (DHA inhibition test. At sufficient concentrations, zinc is toxic to these bacterial cells, and the exposure of the cells to zinc ion resulted in repression of dehydrogenase activity. The patterns of these toxic effects can be mathematically described with logistic dose-response models and in a manner similar to the non-competitive inhibition of enzymes. The threshold concentration above which toxic effect is observed ranged from 0.008 mM for Pseudomonas sp. DAF1 to 0.364 mM for Proteus sp. PLK2. The coefficients of inhibition Ki correlated with the IC50 and indicate that zinc toxicity is dependent on the organism. The Ki and toxicity threshold values predicted from the equations are comparable and are suitable indicators for kinetic analyses of zinc toxicity against bacteria.

  16. Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis

    OpenAIRE

    Udayalaxmi, J.; Bhat, G. K.; S Kotigadde

    2011-01-01

    The present study was conducted to correlate the biotypes of Gardnerella vaginalis strains isolated from cases of bacterial vaginosis and their virulence factors. Thirty-two strains of G. vaginalis isolated from cases of bacterial vaginosis were biotyped. Adherence to vaginal epithelial cells, biofilm production, surface hydrophobicity, phospholipase C and protease activity were tested on these isolates. Biotype 1 was the most prevalent (8; 25%), followed by biotype 2 (7; 21.9%) and biotypes ...

  17. Detection of Bacterial Wilt Pathogen and Isolation of Its Bacteriophage from Banana in Lumajang Area, Indonesia

    Directory of Open Access Journals (Sweden)

    Hardian Susilo Addy

    2016-01-01

    Full Text Available Bacterial wilt disease on banana is an important disease in Lumajang District and causes severe yield loss. Utilizing bacteriophage as natural enemy of pathogenic bacteria has been widely known as one of the control strategies. This research was aimed at determining the causing agent of bacterial wilt on banana isolated from Lumajang area, to obtain wide-host range bacteriophages against bacterial wilt pathogen and to know the basic characteristic of bacteriophages, particularly its nucleic acid type. Causative agent of bacterial wilt was isolated from symptomatic banana trees from seven districts in Lumajang area on determinative CPG plates followed by rapid detection by PCR technique using specific pair-primer. Bacteriophages were also isolated from soil of infected banana crop in Sukodono District. Morphological observation showed that all bacterial isolates have similar characteristic as common bacterial wilt pathogen, Ralstonia solanacearum. In addition, detection of FliC region in all isolates confirmed that all isolates were R. solanacearum according to the presence of 400 bp of FliC DNA fragment. Moreover, two bacteriophages were obtained from this experiment (ϕRSSKD1 and ϕRSSKD2, which were able to infect all nine R. solanacearum isolates. Nucleic acid analysis showed that the nucleic acid of bacteriophages was DNA (deoxyribonucleic acid.

  18. Application of Oligonucleotide Microarrays for Bacterial Source Tracking of Environmental Enterococcus sp. Isolates

    OpenAIRE

    Furey, John S.; Kelley Betts; Indest, Karl J.

    2005-01-01

    In an effort towards adapting new and defensible methods for assessing and managing the risk posed by microbial pollution, we evaluated the utility of oligonucleotide microarrays for bacterial source tracking (BST) of environmental Enterococcus sp. isolates derived from various host sources. Current bacterial source tracking approaches rely on various phenotypic and genotypic methods to identify sources of bacterial contamination resulting from point or non-point pollution. For this study Ent...

  19. “Lachnoclostridium touaregense,” a new bacterial species isolated from the human gut microbiota

    OpenAIRE

    M. Tidjani Alou; S. Khelaifia; B. La Scola; Cassir, N.

    2016-01-01

    We report the main characteristics of “Lachnoclostridium touaregense” strain Marseille-P2415T (= CSUR P2415 = DSM 102219), a new bacterial species isolated from the gut microbiota of a healthy young girl from Niger.

  20. ‘Lachnoclostridium massiliosenegalense’, a new bacterial species isolated from the human gut microbiota

    OpenAIRE

    M. Tidjani Alou; J.-C. Lagier; B. La Scola; Cassir, N.

    2016-01-01

    We report the main characteristics of ‘Lachnoclostridium massiliosenegalense’ strain mt23T (=CSUR P299 =DSM 102084), a new bacterial species isolated from the gut microbiota of a healthy young girl from Senegal.

  1. Anti-bacterial susceptibility patterns of blood culture isolates at a ...

    African Journals Online (AJOL)

    Anti-bacterial susceptibility patterns of blood culture isolates at a referral ... their antimicrobial sensitivity patterns to guide anti-biotic prescription in these settings. ... higher growth rates occurring in the neonatal and paediatric age groups than ...

  2. 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.

  3. Screening of bacterial strains isolated from uranium mill tailings porewaters for bioremediation purposes.

    Science.gov (United States)

    Sánchez-Castro, Iván; Amador-García, Ahinara; Moreno-Romero, Cristina; López-Fernández, Margarita; Phrommavanh, Vannapha; Nos, Jeremy; Descostes, Michael; Merroun, Mohamed L

    2017-01-01

    The present work characterizes at different levels a number of bacterial strains isolated from porewaters sampled in the vicinity of two French uranium tailing repositories. The 16S rRNA gene from 33 bacterial isolates, corresponding to the different morphotypes recovered, was almost fully sequenced. The resulting sequences belonged to 13 bacterial genera comprised in the phyla Firmicutes, Actinobacteria and Proteobacteria. Further characterization at physiological level and metals/metalloid tolerance provided evidences for an appropriate selection of bacterial strains potentially useful for immobilization of uranium and other common contaminants. By using High Resolution Transmission Electron Microscope (HRTEM), this potential ability to immobilize uranium as U phosphate mineral phases was confirmed for the bacterial strains Br3 and Br5 corresponding to Arthrobacter sp. and Microbacterium oxydans, respectively. Scanning Transmission Electron Microscope- High-Angle Annular Dark-Field (STEM-HAADF) analysis showed U accumulates on the surface and within bacterial cytoplasm, in addition to the extracellular space. Energy Dispersive X-ray (EDX) element-distribution maps demonstrated the presence of U and P within these accumulates. These results indicate the potential of certain bacterial strains isolated from porewaters of U mill tailings for immobilizing uranium, likely as uranium phosphates. Some of these bacterial isolates might be considered as promising candidates in the design of uranium bioremediation strategies.

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

    Directory of Open Access Journals (Sweden)

    Sandra I. Concha-Guerrero

    2014-01-01

    Full Text Available The increased use of the nanoparticles (NPs on several processes is notorious. In contrast the ecotoxicological 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 Gammaproteobacteria (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 laterosporus 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.

  5. Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis.

    Science.gov (United States)

    Udayalaxmi, J; Bhat, G K; Kotigadde, S

    2011-01-01

    The present study was conducted to correlate the biotypes of Gardnerella vaginalis strains isolated from cases of bacterial vaginosis and their virulence factors. Thirty-two strains of G. vaginalis isolated from cases of bacterial vaginosis were biotyped. Adherence to vaginal epithelial cells, biofilm production, surface hydrophobicity, phospholipase C and protease activity were tested on these isolates. Biotype 1 was the most prevalent (8; 25%), followed by biotype 2 (7; 21.9%) and biotypes 5 and 8 (5; 15.6%). We did not find any statistical correlation between G. vaginalis biotypes and its virulence factors. Virulence factors expressed by G. vaginalis were not associated with a single biotype.

  6. Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis

    Directory of Open Access Journals (Sweden)

    J Udayalaxmi

    2011-01-01

    Full Text Available The present study was conducted to correlate the biotypes of Gardnerella vaginalis strains isolated from cases of bacterial vaginosis and their virulence factors. Thirty-two strains of G. vaginalis isolated from cases of bacterial vaginosis were biotyped. Adherence to vaginal epithelial cells, biofilm production, surface hydrophobicity, phospholipase C and protease activity were tested on these isolates. Biotype 1 was the most prevalent (8; 25%, followed by biotype 2 (7; 21.9% and biotypes 5 and 8 (5; 15.6%. We did not find any statistical correlation between G. vaginalis biotypes and its virulence factors. Virulence factors expressed by G. vaginalis were not associated with a single biotype.

  7. Isolation of a lead tolerant novel bacterial species, Achromobacter sp. TL-3: assessment of bioflocculant activity.

    Science.gov (United States)

    Batta, Neha; Subudhi, Sanjukta; Lal, Banwari; Devi, Arundhuti

    2013-11-01

    Lead is one of the four heavy metals that has a profound damaging effects on human health. In the recent past there has been an increasing global concern for development of sustainable bioremediation technologies for detoxification of lead contaminant. Present investigation highlights for lead biosorption by a newly isolated novel bacterial species; Achromobacter sp. TL-3 strain, isolated from activated sludge samples contaminated with heavy metals (collected from oil refinery, Assam, North-East India). For isolation of lead tolerant bacteria, sludge samples were enriched into Luria Broth medium supplemented separately with a range of lead nitrate; 250, 500, 750, 1000, 1250 and 1500 ppm respectively. The bacterial consortium that could tolerate 1500 ppm of lead nitrate was selected further for purification of lead tolerant bacterial isolates. Purified lead tolerant bacterial isolates were then eventually inoculated into production medium supplemented with ethanol and glycerol as carbon and energy source to investigate for bioflocculant production. Bioflocculant production was estimated by monitoring the potential of lead tolerant bacterial isolate to flocculate Kaolin clay in presence of 1% CaCl2. Compared to other isolates, TL-3 isolate demonstrated for maximum bioflocculant activity of 95% and thus was identified based on 16S rRNA gene sequence analysis. TL3 isolate revealed maximum homology (98%) with Achromobacter sp. and thus designated as Achromobacter sp. TL-3. Bioflocculant activity of TL-3 isolate was correlated with the change in pH and growth. Achromobacter sp. TL-3 has significant potential for lead biosorption and can be effectively employed for detoxification of lead contaminated waste effluents/waste waters.

  8. 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.

  9. Identification and characterization of humic substances-degrading bacterial isolates from an estuarine environment.

    Science.gov (United States)

    Esham; Ye; Moran

    2000-12-01

    Bacterial isolates were obtained from enrichment cultures containing humic substances extracted from estuarine water using an XAD-8 resin. Eighteen isolates were chosen for phylogenetic and physiological characterization based on numerical importance in serial dilutions of the enrichment culture and unique colony morphology. Partial sequences of the 16S rRNA genes indicated that six of the isolates were associated with the alpha subclass of Proteobacteria, three with the gamma-Proteobacteria, and nine with the Gram-positive bacteria. Ten isolates degraded at least one (and up to six) selected aromatic single-ring compounds. Six isolates showed ability to degrade [(14)C]humic substances derived from the dominant salt marsh grass in the estuary from which they were isolated (Spartina alterniflora), mineralizing 0.4-1.1% of the humic substances over 4 weeks. A mixture of all 18 isolates did not degrade humic substances significantly faster than any of the individual strains, however, and no isolate degraded humic substances to the same extent as the natural marine bacterial community (3.0%). Similar studies with a radiolabeled synthetic lignin ([beta-(14)C]dehydropolymerisate) showed measurable levels of degradation by all 18 bacteria (3.0-8.8% in 4 weeks), but mineralization levels were again lower than that observed for the natural marine bacterial community (28.2%). Metabolic capabilities of the 18 isolates were highly variable and generally did not map to phylogenetic affiliation.

  10. Isolation and distribution of bacterial flora in farmed rainbow trout from Mexico.

    Science.gov (United States)

    Salgado-Miranda, Celene; Palomares, Elizabeth; Jurado, Mirsam; Marín, Aída; Vega, Fernando; Soriano-Vargas, Edgardo

    2010-12-01

    Trout farming is a growing aquaculture industry in Mexico, with stock mainly supplied by the importation of eyed eggs. The aim of the present study was to determine the frequency of bacterial isolations in farmed rainbow trout Oncorhynchus mykiss from Mexico. Sixty-five farms distributed among seven states of Mexico were included in the study. Individual samples from gills, liver, spleen, intestine, and kidney were obtained from 563 apparently healthy fish. In total, 371 bacterial isolates were recovered from sampled fish; isolates of the genera Aeromonas, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Plesiomonas, Pseudomonas, and Yersinia were identified. Aeromonads were the most frequently isolated bacteria. Renibacterium salmoninarum was not isolated from any of the sampled fish. Our results showed the presence of bacteria that are potential pathogens of both rainbow trout and humans.

  11. Isolation and molecular characterisation of malathion-degrading bacterial strains from waste water in Egypt

    Directory of Open Access Journals (Sweden)

    Zeinat K. Mohamed

    2010-04-01

    Full Text Available Efficiencies of local bacterial isolates in malathion degradation were investigated. Five bacterial isolates obtained from agricultural waste water were selected due to their ability to grow in minimal salt media, supplied with 250 ppm malathion as sole source of carbon and phosphorus. The purified bacterial isolates (MOS-1, MOS-2, MOS-3, MOS-4 and MOS-5 were characterised and identified using a combination of cellular profile (SDS-PAGE, genetic make up profile (RAPD-PCR, and morphological and biochemical characteristics. Four bacterial isolates (MOS-1, MOS-2, MOS-3 and MOS-4 with identical genetic characteristics were identified as Enterobacter aerogenes, whereas isolate MOS-5 was identified as Bacillus thuringiensis. The degradation rate of malathion in liquid culture was estimated during 15 days of incubation for the isolate MOS-5 of B. thuringiensis. Slightly more than 50% of the initial malathion was decomposed within 3 days. The malathion concentration decreased to almost 17% in the inoculated medium after 10 days incubation, while more than 91% of the initial malathion was degraded after 15 days.

  12. DETERMINATION OF THE SEEDLING REACTIONS OF TWENTY BARLEY CULTIVARS TO SIX ISOLATES OF DRECHSLERA TERES F. MACULATA

    OpenAIRE

    Pınar USTA; KARAKAYA, Aziz; OĞUZ, Arzu ÇELİK; MERT, Zafer; AKAN, Kadir; ÇETİN, Lütfi

    2014-01-01

    Seedling reactions of 20 barley cultivars grown in Turkey were determined under greenhouse conditions to six isolates of Drechslera teres f. maculata, the causal agent of spot form of barley net blotch disease. Isolates were obtained from different provinces of Turkey. Differences among the reactions of the cultivars to the isolates of the fungus were observed. Isolate differences in pathogenicity for each cultivar were also present. The reactions of cultivars to the isolates ranged betwee...

  13. Genome Sequences of Nine Gram-Negative Vaginal Bacterial Isolates

    Science.gov (United States)

    Deitzler, Grace E.; Ruiz, Maria J.; Lu, Wendy; Weimer, Cory; Park, SoEun; Robinson, Lloyd S.; Hallsworth-Pepin, Kymberlie; Wollam, Aye; Mitreva, Makedonka

    2016-01-01

    The vagina is home to a wide variety of bacteria that have great potential to impact human health. Here, we announce reference strains (now available through BEI Resources) and draft genome sequences for 9 Gram-negative vaginal isolates from the taxa Citrobacter, Klebsiella, Fusobacterium, Proteus, and Prevotella. PMID:27688330

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

    African Journals Online (AJOL)

    Purpose: To investigate the incidence of different bacteria isolates in 150 wound ... Methods: Wound swab samples were collected from general culture bench of the ... Index Medicus, JournalSeek, Journal Citation Reports/Science Edition, Directory of Open Access Journals ... was used to flood the surface of Mueller Hinton.

  15. Bacterial-Feeding Nematode Growth and Preference for Biocontrol Isolates of the Bacterium Burkholderia cepacia.

    Science.gov (United States)

    Carta, L K

    2000-12-01

    The potential of different bacterial-feeding Rhabditida to consume isolates of Burkholderia cepacia with known agricultural biocontrol ability was examined. Caenorhabditis elegans, Diploscapter sp., Oscheius myriophila, Pelodera strongyloides, Pristionchus pacificus, Zeldia punctata, Panagrellus redivivus, and Distolabrellus veechi were tested for growth on and preference for Escherichia coli OP50 or B. cepacia maize soil isolates J82, BcF, M36, Bc2, and PHQM100. Considerable growth and preference variations occurred between nematode taxa on individual bacterial isolates, and between different bacterial isolates on a given nematode. Populations of Diploscapter sp. and P. redivivus were most strongly suppressed. Only Z. punctata and P. pacificus grew well on all isolates, though Z. punctata preferentially accumulated on all isolates and P. pacificus had no preference. Oscheius myriophila preferentially accumulated on growth-supportive Bc2 and M36, and avoided less supportive J82 and PHQM100. Isolates with plant-parasitic nematicidal properties and poor fungicidal properties supported the best growth of three members of the Rhabditidae, C. elegans, O. myriophila, and P. strongyloides. Distolabrellus veechi avoided commercial nematicide M36 more strongly than fungicide J82.

  16. 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.

  17. 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.

  18. Comparison of Hemagglutination and Hemolytic Activity of Various Bacterial Clinical Isolates Against Different Human Blood Groups

    Science.gov (United States)

    HRV, Rajkumar; Devaki, Ramakrishna

    2016-01-01

    Among the various pathogenic determinants shown by microorganisms hemagglutination and hemolysin production assume greater significance in terms of laboratory identification. This study evaluated the hemagglutination and hemolytic activity of various bacterial isolates against different blood groups. One hundred and fifty bacterial strains, isolated from clinical specimens like urine, pus, blood, and other body fluids were tested for their hemagglutinating and hemolytic activity against human A, B, AB, and O group red blood cells. Among the 150 isolates 81 were Escherichia coli, 18 were Klebsiella pneumoniae, 19 were Pseudomonas aeruginosa, 10 were Pseudomonas spp, six were Proteus mirabilis, and the rest 16 were Staphylococcus aureus. Nearly 85% of the isolates agglutinated A group cells followed by B and AB group (59.3% and 60.6% respectively). Least number of isolates agglutinated O group cells (38.0%). When the hemolytic activity was tested, out of these 150 isolates 79 (52.6%) hemolyzed A group cells, 61 (40.6%) hemolyzed AB group cells, 46 (30.6%) hemolyzed B group cells, and 57 (38.6%) isolates hemolyzed O group cells. Forty-six percent of the isolates exhibited both hemagglutinating and hemolytic property against A group cells, followed by B and AB group cells (28.6% and 21.3% respectively). Least number of isolates i.e., 32 (21.3%) showed both the properties against O group cells. The isolates showed wide variation in their hemagglutination and hemolytic properties against different combinations of human blood group cells. The study highlights the importance of selection of the type of cells especially when human RBCs are used for studying the hemagglutination and hemolytic activity of bacterial isolates because these two properties are considered as characteristic of pathogenic strains. PMID:27014523

  19. Importance of isolation and biotypization of Gardnerella vaginalis in diagnosis of bacterial vaginosis.

    Science.gov (United States)

    Numanović, Fatima; Hukić, Mirsada; Nurkić, Mahmud; Gegić, Merima; Delibegović, Zineta; Imamović, Alma; Pasić, Selma

    2008-08-01

    The natural habitat of Gardnerella vaginalis is a vagina since it could be located among 69% of women who have no signs of vaginal infection and in the vagina of as many as 13.5% girls. G. vaginalis is almost certainly identified among women diagnosed with bacterial vaginosis as well as in the urethra of their sexual partner. The increase in prevalence and concentration of G. vaginalis among patients diagnosed with this syndrome confirms that G. vaginalis plays a significant role in its pathogenesis. In our research, based on Amsel criteria for three or more clinical signs of bacterial vaginosis, it was diagnosed in 20.5% of women with subjective problems of vaginal infection, and in 48.80% of women with subjective symptoms characteristic of this disease. G. vaginalis was isolated from vaginal secretion of women without clinical signs characteristic of bacterial vaginosis. In 2.58% of cases it was solitary, while in 1.28% it was found in combination with other aerobic and anaerobic bacteria and, in 1.28% women combined with Candida albicans. The isolation of G. vaginalis was significantly increased (pbiotype of G. vaginalis, different from a source biotype or as a consequence of wrong treatment. Following Piot biotype scheme, biotypes 2., 3. and 7. G. vaginalis are significantly more often isolated from women who suffer from bacterial vaginosis. Biotype 7. G. vaginalis, isolated from the group of women without clinical signs of bacterial vaginosis, accounted for 2.58% cases. Following Benit biotype scheme, biotypes IVa, IVc and IIc were identified in 12.90% cases, while biotypes IIIa, IIa, Ia, IVb, IIb were found in 6.45% cases. Lipase-positive isolates of G. vaginalis were significantly more frequently accompanied by the syndrome of bacterial vaginosis.

  20. 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

  1. 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 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. Th...

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

    OpenAIRE

    Rhea eLumactud; Shu Yi eShen; Mimas eLau; Roberta eFulthorpe

    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....

  3. 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.

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

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    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.

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

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    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.

  6. Isolation and Identification of Active Compound Cause Light Emmitting of Bacterial Photobacterium phosphoreum Isolated from the Indonesia Jepara Marine Squid

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    Idam Arif

    2005-04-01

    Full Text Available This research carried out to study the bioluminescence process of bacterial Photobacterium phosphoreum isolated from Indonesia marine squid. The method used in the present study involved isolation, purification, electrophoresis, and the absorbance and light intensity measurement. This result show that the luciferace enzyme of bacterial Photobacterium phosphoreum or called LBPP catalyzes the emission of visible light from the reaction of reduced flavin mononucleotide (FMNH2, molecular oxygen (O2, and an aldehyde (RCOH. The electrophoresis data show that LBPP comprised of two different subunits α and βwith 41kD and 38 kD molecular weights. The absorb pattern showed that the bioluminescence process centered around 516 nm and are consistent with the fluorescence data. This result concluded that the excitation state formed after LBPP bind subtracts and the ground state formed after LBPP releases product and visible light.

  7. 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 BZ-6 was found to be the most efficient strain and the three phases (oil, water and sediment) were separated automatically after the sludge was treated with the culture medium of BZ-6. Based on morphological, physiological characteristics and molecular 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.

  8. 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.

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

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    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.

  10. Comparison of different methods for isolation of bacterial DNA from retail oyster tissues

    Science.gov (United States)

    Oysters are filter-feeders that bio-accumulate bacteria in water while feeding. To evaluate the bacterial genomic DNA extracted from retail oyster tissues, including the gills and digestive glands, four isolation methods were used. Genomic DNA extraction was performed using the Allmag™ Blood Genomic...

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

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

    Institute of Scientific and Technical Information of China (English)

    Guru Prasad Srinivasan; Asnar Sikkanthar; Anandajothi Elamaran; Caroline R Delma; Kumaran Subramaniyan

    2014-01-01

    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.

  17. Antibacterial synergy of curcumin with antibiotics against biofilm producing clinical bacterial isolates

    Science.gov (United States)

    Kali, Arunava; Bhuvaneshwar, Devaraj; Charles, Pravin M. V.; Seetha, Kunigal Srinivasaiah

    2016-01-01

    Introduction: The role of natural bioactive substances in treating infections has been rediscovered as bacterial resistance become common to most of the antibiotics. Curcumin is a bioactive substance from turmeric. Owing to antimicrobial properties, its prospect as an antibacterial agent is currently under focus. Materials and Methods: We have evaluated the in vitro synergy of curcumin with antibiotics against sixty biofilm producing bacterial isolates. Congo red agar method was used to identify the biofilm producing isolates. Curcumin minimum inhibitory concentration (MIC) was determined by agar dilution method. Its antibiotic synergy was identified by the increase in disc diffusion zone size on Mueller-Hinton agar with 32 mg/L curcumin. Results: The mean MICs of curcumin against Gram-positive and Gram-negative isolates were 126.9 mg/L and 117.4 mg/L, respectively. Maximum synergy was observed with ciprofloxacin among Gram-positive and amikacin, gentamicin, and cefepime among Gram-negative isolates. Conclusions: Curcumin per se as well as in combination with other antibiotics has a demonstrable antibacterial action against biofilm producing bacterial isolates. It may have a beneficial role in supplementing antibiotic therapy. PMID:27330262

  18. 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.

  19. 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

  20. Bacterial isolates from the bryozoan Membranipora membranacea: influence of culture media on isolation and antimicrobial activity.

    Science.gov (United States)

    Heindl, Herwig; Thiel, Vera; Wiese, Jutta; Imhoff, Johannes F

    2012-03-01

    From specimens of the bryozoan Membranipora membranacea collected in the Baltic Sea, bacteria were isolated on four different media, which significantly increased the diversity of the isolated groups. All isolates were classified according to 16S rRNA gene sequence analysis and tested for antimicrobial properties using a panel of five indicator strains and six different media. Each medium featured a unique set of isolated phylotypes, and a phylogenetically diverse collection of isolates was obtained. A total of 96 isolates were assigned to 49 phylotypes and 29 genera. Only one-third of the members of these genera had been isolated previously from comparable sources. The isolates were affiliated with Alpha- and Gammaproteobacteria, Bacilli, and Actinobacteria. A comparable large portion of up to 22 isolates, i.e., 15 phylotypes, probably represent new species. Likewise, 47 isolates (approximately 50%) displayed antibiotic activities, mostly against grampositive indicator strains. Of the active strains, 63.8 % had antibiotic traits only on one or two of the growth media, whereas only 12.7 % inhibited growth on five or all six media. The application of six different media for antimicrobial testing resulted in twice the number of positive hits as obtained with only a single medium. The use of different media for the isolation of bacteria as well as the variation of media considered suitable for the production of antibiotic substances significantly enhanced both the number of isolates obtained and the proportion of antibiotic active cultures. Thus the approach described herein offers an improved strategy in the search for new antibiotic compounds.

  1. Pathogenicity testing of shellfish hatchery bacterial isolates on Pacific oyster Crassostrea gigas larvae.

    Science.gov (United States)

    Estes, Robyn M; Friedman, Carolyn S; Elston, Ralph A; Herwig, Russell P

    2004-03-10

    Bacterial diseases are a major cause of larval mortality in shellfish hatcheries. Even with proper sanitation measures, bacterial pathogens cannot be eliminated in all cases. The pathogenicity of bacteria isolated from Pacific Northwest shellfish hatcheries to Pacific oyster Crassostrea gigas larvae was investigated. We found 3 highly pathogenic strains and 1 mildly pathogenic strain among 33 isolates tested. These strains appear to be members of the genus Vibrio. Although there have been many studies of bivalve bacterial pathogens, a standard method to assess bacterial pathogenicity in bivalve larvae is needed. Thus, we developed 2 methods using either 15 ml conical tubes or tissue culture plates that were employed for rapidly screening bacterial strains for pathogenicity to Pacific oyster larvae. The tissue culture plates worked well for screening both mildly pathogenic strains and LD50 (lethal dose) assays. This method allowed for non-intrusive and non-destructive observation of the oyster larvae with a dissecting microscope. The LD50 for the 3 highly pathogenic strains ranged between 1.6 and 3.6 x 10(4) colony forming units (CFU) ml(-1) after 24 h and between 3.2 x 102 and 1.9 x 10(3) CFU ml(-1) after 48 h.

  2. 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.

  3. Comparison of Mycoplasma ovipneumoniae isolates using bacterial restriction endonuclease DNA analysis and SDS-PAGE.

    Science.gov (United States)

    Mew, A J; Ionas, G; Clarke, J K; Robinson, A J; Marshall, R B

    1985-12-01

    Sixteen isolates of Mycoplasma ovipneumoniae recovered from the nasal tract or lungs of sheep from different flocks in New Zealand were examined by bacterial restriction endonuclease DNA analysis (BRENDA) using EcoR1 and by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). All isolates gave BRENDA patterns which differed entirely from one another. Following 20 serial passages (corresponding to approximately 67 generations) of an isolate, no change was detected in the BRENDA pattern. When eight isolates were examined by SDS-PAGE most bands were common but, nevertheless, each isolate was unique in the sense that they differed from one another in one or more bands. The marked heterogeneity of patterns observed when strains of M. ovipneumoniae are compared by BRENDA, together with the stability of such patterns over many generations, will enable this approach to be used to study the epidemiology of individual strains of M. ovipneumoniae within a flock.

  4. CHARACTERISATION OF BACTERIAL ISOLATES FROM INFECTE D BURN WOUNDS OF PATIENTS ADMITTED IN A TERTIARY LEVEL HEA LTH CARE FACILITY IN NORTHERN REGION OF INDIA

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    Antariksh

    2013-04-01

    Full Text Available ABSTRACT: Infection is an important cause of mortality in bur ns. Emergence of multi drug resistant pathogens in hospital setting has seriously constrained the available therapeutic options. This necessitates periodic review of the iso lation pattern and study of antibiogram of the isolates to strengthen surveillance activities. To determine the bacteriological profile and antimic robial susceptibility pattern of pathogens isolated from infected burn wounds of pati ents admitted in the burns care unit. The present study was carried out over a duration of six months. Pus samples from infected burn wounds were processed following standard protocols. A ntimicrobial susceptibility of the bacterial isolates was performed by Kirby- Bauer dis c diffusion method. A total of 408 bacterial pathogens were isolated from 340 samples. The most fr equent cause of infection was found to be Pseudomonas aeruginosa (53%, followed by Staphyl ococcus aureus (9%, Escherichia coli (9%, Enterobacter spp. (8%, Citrobacter spp. (8%, Kl ebsiella spp. (5%, Acinetobacter spp. (3% and Proteus spp. (3%. High level of drug resist ance (95-100% was observed for cefepime, ceftazidime, amoxyclav, cotrimoxazole and doxycycline among gram negative pathogens. Meropenem, amikacin and ciprofloxacin were found to be most effective. Twenty one percent of the S. aureus isolates were resistant to methicillin. The high prevalence of antimicrobial resistance emphasizes the need for str engthening the infection control practices and regular and periodical surveillance activities t o contain the upward trend of resistance.

  5. 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 product analysis showed structural changes and formation of bacterial film on degraded LDPE strips. The 16S rDNA characterization of bacterial consortia revealed that these organisms were novel strains and designated as Enterobacter sp. bengaluru-btdsce01, Enterobacter sp. bengaluru-btdsce02, and Pantoea sp. bengaluru-btdsce03. The current study thus suggests that industrial scale-up of these microbial consortia probably provides better insights for waste management of LDPE and similar types of plastic garbage.

  6. Spatial pattern in Antarctica: what can we learn from Antarctic bacterial isolates?

    Science.gov (United States)

    Chong, Chun Wie; Goh, Yuh Shan; Convey, Peter; Pearce, David; Tan, Irene Kit Ping

    2013-09-01

    A range of small- to moderate-scale studies of patterns in bacterial biodiversity have been conducted in Antarctica over the last two decades, most suggesting strong correlations between the described bacterial communities and elements of local environmental heterogeneity. However, very few of these studies have advanced interpretations in terms of spatially associated patterns, despite increasing evidence of patterns in bacterial biogeography globally. This is likely to be a consequence of restricted sampling coverage, with most studies to date focusing only on a few localities within a specific Antarctic region. Clearly, there is now a need for synthesis over a much larger spatial to consolidate the available data. In this study, we collated Antarctic bacterial culture identities based on the 16S rRNA gene information available in the literature and the GenBank database (n > 2,000 sequences). In contrast to some recent evidence for a distinct Antarctic microbiome, our phylogenetic comparisons show that a majority (~75 %) of Antarctic bacterial isolates were highly similar (≥99 % sequence similarity) to those retrieved from tropical and temperate regions, suggesting widespread distribution of eurythermal mesophiles in Antarctic environments. However, across different Antarctic regions, the dominant bacterial genera exhibit some spatially distinct diversity patterns analogous to those recently proposed for Antarctic terrestrial macroorganisms. Taken together, our results highlight the threat of cross-regional homogenisation in Antarctic biodiversity, and the imperative to include microbiota within the framework of biosecurity measures for Antarctica.

  7. Application of Oligonucleotide Microarrays for Bacterial Source Tracking of Environmental Enterococcus sp. Isolates

    Directory of Open Access Journals (Sweden)

    John S. Furey

    2005-04-01

    Full Text Available In an effort towards adapting new and defensible methods for assessing and managing the risk posed by microbial pollution, we evaluated the utility of oligonucleotide microarrays for bacterial source tracking (BST of environmental Enterococcus sp. isolates derived from various host sources. Current bacterial source tracking approaches rely on various phenotypic and genotypic methods to identify sources of bacterial contamination resulting from point or non-point pollution. For this study Enterococcus sp. isolates originating from deer, bovine, gull, and human sources were examined using microarrays. Isolates were subjected to Box PCR amplification and the resulting amplification products labeled with Cy5. Fluorescent-labeled templates were hybridized to in-house constructed nonamer oligonucleotide microarrays consisting of 198 probes. Microarray hybridization profiles were obtained using the ArrayPro image analysis software. Principal Components Analysis (PCA and Hierarchical Cluster Analysis (HCA were compared for their ability to visually cluster microarray hybridization profiles based on the environmental source from which the Enterococcus sp. isolates originated. The PCA was visually superior at separating origin-specific clusters, even for as few as 3 factors. A Soft Independent Modeling (SIM classification confirmed the PCA, resulting in zero misclassifications using 5 factors for each class. The implication of these results for the application of random oligonucleotide microarrays for BST is that, given the reproducibility issues, factor-based variable selection such as in PCA and SIM greatly outperforms dendrogram-based similarity measures such as in HCA and K-Nearest Neighbor KNN.

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

    Science.gov (United States)

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

    2016-09-01

    The isolation and analysis of single prokaryotic cells down to 1 μm 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 μm in size. Further, the magnification of the optical system used for cell detection was increased. Redesign of the optical path allows for collision-free addressing of any flat substrate since no compartment protrudes below the nozzle of the dispenser chip anymore. The improved system allows for deterministic isolation of individual bacterial cells. A single-cell printing efficiency of 93% was obtained as shown by printing fluorescent labeled E. coli. A 96-well plate filled with growth medium is inoculated with single bacteria cells on average within about 8 min. Finally, individual bacterial cells from a heterogeneous sample of E. coli and E. faecalis were isolated for clonal culturing directly on agar plates in user-defined array geometry.

  9. 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

  10. In vitro Evaluation of the Effct of Bacterial Extract, Isolated From Infected Hydatid Cysts, on Protoscolex

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    Sardari M

    2017-03-01

    Full Text Available Introduction: To date, surgery has been the treatment of choice for hydatid cyst, with regard to danger of leakage of hydatid cyst contents into viscera and production of secondary cysts, aftr spread of protoscolices. Diffrent scolicidal agents get injected into cyst for preventing the secondary cyst production, which may cause diffrent side effcts in host, especially in the surrounding tissues. In this research, the scolicidal effcts of bacterial extract isolated from infected hydatid cyst was evaluated. Methods: In this experimental-laboratorial study, at fist, isolation and identifiation of the infecting bacteria of hydatid cyst were performed at the level of species. Thn, total the bacterial extract was prepared by sonication method, and serial dilutions 1.1, 1.2, 1.4, 1.8, 1.16, 1.32 and 1.64( were prepared using sterile saline as the solvent. Th obtained alive larvae at the times of 5, 10, 20, 40 and 60 minutes were placed in those dilutions and mean of dead protoscoleces were determined using eosin exclusive staining method. Results: Th identifid bacteria isolated from the infected hydatid cysts were as follows: E. coli, Staphylococcus aureus, S. saprophyticus, Proteus mirabilis and Pseudomonas aeruginosa. Th extract of isolated bacteria at the mentioned times had no considerable scolicidal effcts. For example, the whole extract of P. aeruginosa aftr 60 minutes of exposure showed a maximum of 13.17%. scolicidal effct. Conclusion: Th results of this study showed low scolicidal effct of bacterial extracts isolated from hydatid cyst. Degeneration of scolices in infected cysts can be due to other reasons than bacterial extract.

  11. Probiotic Activity of a Bacterial Strain Isolated from Ancient Permafrost Against Salmonella Infection in Mice.

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    Fursova, O; Potapov, V; Brouchkov, A; Pogorelko, G; Griva, G; Fursova, N; Ignatov, S

    2012-09-01

    Bacillus cereus strain F, collected from relict permafrost located in Siberia, was analyzed for probiotic activity in the mouse Salmonella enterica model. Viable bacterial cells were found in frozen soils taken at Mammoth Mountain in Yakutia from a depth below the level of seasonal thawing. Geological data indicated the absence of a thawing within millions of years of deposited soils, which helped to ensure the ancient origin of our sample. According to DNA analysis, bacterial cells collected from the relict permafrost appeared to be B. cereus strain F. The morphology of these bacteria was analyzed using atomic force microscopy. B. cereus strain F was assessed as a nonpathogenic bacterium by evaluation of its pathogenicity. A S. enterica model is described in mice after per oral inoculation and serves as a model for the human carrier state. Using this model, probiotic activity by the bacterial strain isolated from the ancient permafrost has been shown against Salmonella infection in mice.

  12. Relationship between the GOLD combined COPD assessment staging system and bacterial isolation

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    Aydemir Y

    2014-09-01

    Full Text Available Yusuf Aydemir,1 Özlem Aydemir,2 Fatma Kalem3 1Department of Respiratory Medicine, Sakarya University, Sakarya, Turkey; 2Department of Microbiology, Sakarya University, Sakarya, Turkey; 3Department of Microbiology, Konya Numune Hospital, Konya, Turkey Background: Acute exacerbations, which are a significant cause of mortality and morbidity, adversely affect chronic obstructive pulmonary disease (COPD prognosis by accelerating loss of lung function. It is important to know the microorganisms that commonly cause exacerbations in the patient groups classified according to clinical and functional characteristics for fast and accurate treatment of acute exacerbations. Objectives: The last Global Initiative for Chronic Obstructive Lung Disease (GOLD publication recommended a new staging system containing obstruction degree, frequency of exacerbations, and quality of life questionnaires. This study is designed to analyze the relationship between the bacteria isolated in acute exacerbations and new GOLD stages. Methods: Potentially pathogenic bacteria (PPB isolation with culture and polymerase chain reaction methods were obtained from 114 acute exacerbation COPD patients, classified into A, B, C, and D groups by analyzing the forced expiratory volume in 1 second (FEV1 value, COPD Assessment Test (CAT score, and exacerbation frequency according to the new GOLD staging system. Results: There was a significant correlation between exacerbation frequency and PPB isolation (P=0.002. There was no relationship between GOLD stage, FEV1, and CAT score with PPB isolation. The isolated bacteria diversity and mixed infection frequency were higher in the GOLD stage D group. Pseudomonas aeruginosa, Escherichia coli, and Acinetobacter baumannii were isolated only from D group patients. Conclusion: Bacterial infection may cause an acute exacerbation equally in each stage for COPD. The difference in bacterial etiology is more related to exacerbation frequency than FEV1

  13. Screening of bovine milk samples for sub-clinical mastitis and antibiogram of bacterial isolates

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    Harini H. and Sumathi B.R.

    Full Text Available The study was undertaken to find out the incidence of subclinical mastitis (SCM and to assess the antibiotic sensitivity pattern of the causative organisms in lactating cows in and around Kanakapura taluk, Ramanagara district of Karnataka state. The prevalence of subclinical mastitis was assessed by the results of 3 different screening tests and bacteriological evaluation was done for the milk samples that were found positive. The predominant bacterial isolates recovered were Staphylococcus aureus (58% and Escherichia coli (23.5% followed by Staphylococcus epidermidis (8%, Streptococcus sp. (5.5%, Klebsiella sp. (3% and Bacillus sp. (2%. The in vitro antibiogram studies of bacterial isolates revealed higher sensitivity for ciprofloxacin (89%, ofloxacin (85%, enrofloxacin (82%, gentamicin (80% and chloramphenicol (75%, resistant to colistin, neomycin, streptomycin, penicillin and tetracycline. [Vet. World 2011; 4(8.000: 358-359

  14. 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.

  15. 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.

  16. 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.

  17. Frequency of isolation and antimicrobial susceptibility pattern of bacterial isolates from blood culture, Gondar University teaching hospital, Northwest Ethiopia.

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    Ali, Jemal; Kebede, Yenew

    2008-04-01

    Bacterial bloodstream infections cause substantial morbidity and mortality, with up to one-quarter of affected patients dying as a result of their infection. Up-to-date information on blood culture isolates and their antimicrobial susceptibility pattern is very important as guide for immediate prescription of antimicrobial agents and monitoring of emergence of drug resistant strains. To determine the frequency of blood culture isolation and antimicrobial susceptibility pattern of isolates in Gondar University teaching hospital. This was retrospective analysis of records of blood culture results for febrile patients seen at Gondar University teaching hospital, bacteriology section from March 2001 to April 2005. During the four years period, blood cultures were done for a total of 472 febrile patients. Among these, 233 (49.4%) were females and 239 (50.6%) were males. The median age was 20.5 years (age range of 2 hours to 78 years). Out of these, total of 114 bacterial strains were isolated with culture positivity rate of 24.2%. Coagulase-negative Staphylococci (CoNS) were isolated with the highest frequency in 38 (33.3%), followed by Staphylococcus aureus in 34 (29.8%), Salmonella species other than Salmonella typhi in 12 (10.5%), Klebsiella species in 10 (8.8%), Streptococcus pneumoniae in 6 (5.3%), Salmonella typhi in 4 (3.5%), Enterobacter species in 3 (2.6%), Escherichia coli in 2 (1.7%). The gram positive and gram negative bacteria constituted 80 (70.2%) and 34 (29.8%) of the culture isolates, respectively. Culture positivity rates vary as for neonates, 63% (17 out of 27);followed by 25.6% (36 out of 141) in children and 20% (61 out of 304) in adults. The isolates especially gram negative bacteria showed multiple drug resistance, to Ampicillin and penicillin. However, ciprofloxacin is fairly effective against both gram negative and gram positive isolates. An effective documented data may serve as a guide for initial empirical treatment of bloodstream infections

  18. 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.

  19. 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

    ABSTRACT 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. PMID:23015740

  20. [Polyvalence of bacteriophages isolated from fruit trees, affected by bacterial fire blight].

    Science.gov (United States)

    Tovkach, F I; Moroz, S N; Korol', N A; Faĭdiuk, Iu V; Kushkina, A I

    2013-01-01

    Phage populations appearing as a result of a pathogenic process caused by Erwinia amylovora have been discovered and described. They accompany bacterial fire blight development in the process of quince, pear and apple trees vegetation in Zakarpattya region of Ukraine. Phage isolates of the affected pear and quince include polyvalent virulent phages able to develop on bacterial strains associated with plants--E. amylovora. E. "horticola" and Pantoea agglomerans. E. amylovora isolated from the plant tissues affected by the fire blight and detected at the same time as phages proved to be resistant to the viral infection. It is hard to explain now this characteristic however it was noticed that resistance to phages can change drastically in case of dissociation, lysogenization and mutagenesis of erwinia in laboratory conditions. Phage population study shows that they are heterogeneous and can obviously include not only polyvalent but also specific viruses. Further studies of biology and molecular genetics of pure lines of isolated phages will help to get closer to understanding the place and role of bacteriophages in the complicated network of relations between bacterial pathogens and plants.

  1. 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.

  2. Heterogeneity in restriction patterns of Gardnerella vaginalis isolates from individuals with bacterial vaginosis.

    Science.gov (United States)

    Nath, K; Devlin, D; Beddoe, A M

    1992-02-01

    This study was undertaken to resolve the genetic make up of Gardnerella vaginalis present in bacterial vaginosis (BV). DNA from several G. vaginalis isolates from within and between individual BV patients were compared by BamHI, ClaI and EcoRI restriction endonuclease analysis (REA) followed by a restriction fragment length polymorphism (RFLP) study, utilizing a 5.7-kb BamHI G. vaginalis ATCC14018 DNA probe. Four G. vaginalis isolates from one patient (GVP-062) were composed of 3 different biotypes (biotypes 3, 5 and 8), and while the REA mirrored the biotype, in RFLP studies at least 3 isolates had DNA fragments in common. All of the isolates from 2 other patients (GVP-063 and GVP-072) represented a single biotype (biotype 2), but under REA and in RFLP studies, the isolates GVP-063 differed from GVP-072. An opposite case existed with the isolates GVP-072 (biotype 2) and GVP-065 (biotype 5), which appeared similar under REA and in RFLP studies. Finally, reisolates after 8 weeks (GVP-080) from a BV patient (isolates GVP-065) representing the same biotype (biotype 5) differed under REA and in RFLP studies. Thus, lacking any unique DNA fingerprint, G. vaginalis occurring in BV represents a (genetically) mixed population.

  3. Survival and transfer ability of phylogenetically diverse bacterial endosymbionts in environmental Acanthamoeba isolates.

    Science.gov (United States)

    Matsuo, Junji; Kawaguchi, Kouhei; Nakamura, Shinji; Hayashi, Yasuhiro; Yoshida, Mitsutaka; Takahashi, Kaori; Mizutani, Yoshihiko; Yao, Takashi; Yamaguchi, Hiroyuki

    2010-08-01

    Obligate intracellular bacteria are commonly found as endosymbionts of acanthamoebae; however, their survival in and ability to transfer to amoebae are currently uncharacterized. In this study, six bacterial endosymbionts, found in five environmental Acanthamoeba isolates (S13, R18, S23, S31, S40) from different locations of Sapporo city, Japan, were characterized. Phylogenetic analysis revealed that three bacterial endosymbionts (eS23, eS31, eS40a) belonged to α- and β-Proteobacteria phyla and the remaining endosymbionts (eS13, eR18, eS40b) belonged to the order Chlamydiales. The Acanthamoeba isolate (S40) contained two phylogenetically different bacterial endosymbionts (eS40a, eS40b). Fluorescent in situ hybridization analysis showed that all bacterial endosymbionts were diffusely localized within amoebae. Transmission electron microscopy also showed that the endosymbionts were rod-shaped (eS23, eS31, eS40a) or sphere- or crescent-shaped (eS13, eR18, eS40b). No successful culture of these bacteria was achieved using conventional culture methods, but the viability of endosymbionts was confirmed by live/dead staining and RT-PCR methods. However, endosymbionts (except eR18) derived from original host cells lost the ability to be transferred to another Acanthamoebae strains [ATCC strain (C3), environmental strains (S14, R23, S24)]. Thus, our data demonstrate that phylogenetically diverse bacterial endosymbionts found in amoebae maintain a stable interaction with amoebae, but the transferability is limited.

  4. Bacterial Agents Isolated from Wards’ Environment and Staff’s Hands in Yahyanejad Hospital, Babol

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    Sadighian, F. (BSc

    2013-01-01

    Full Text Available Background and Objective: Nowadays, nosocomial infection is one of the greatest problems in hospitals. Normal flora of staff’s hands and the bacterial agents on the surface of medical equipment can become progressively colonized with potential pathogens during patient care. This study was carried out to determine the bacterial agents existed on staff’s hands and in the wards of hospital to step in to control nosocomial infection. Material and Methods: In this descriptive study, during 17 months (22.mar.2010- 30.aug.2011, 403 samples, using sterile swab , were randomly obtained from the staff’s hands and medical equipment of emergency departments , ICU, male operation room and female surgical unit . The samples were cultured on Blood agar (BA and Eosin methylene blue (EMB. Then, identification of isolated bacteria was done with diagnostic tests. Results: Of 430 samples, 530 bacteria were isolated from staff’s hands (N= 291 and medical equipment (N= 234. The most common bacterium from personnel’s hands (144; 49.5% and medical equipment (24; 10% is Staphylococcus aureus. Also, three isolates of pseudomonas aeruginosa from staff’s hands of male surgical ward and medical equipment of ICU, and two isolates of Acinetobacter.spp from ICU’s medical equipment were identified. Conclusion: With regard to the findings, it seems that applying the appropriate disinfectant agents by using standard procedures is necessary. Keywords: Medical Equipment; Staff’s Hand; Nosocomial Infection; Staphylococcus Aureus

  5. 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.

  6. Physiological and Molecular Characteristics of Bacterial Isolates from Bandealit Coastal Area Jember, East Java, Indonesia

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    DINA FITRIYAH

    2013-06-01

    Full Text Available Bacteria are the most dominant group of microorganisms in aquatic environments due to their role in organic matter decomposition. Decomposition activity is related to the type and dominance of bacteria in the communities. Therefore, study of bacterial diversity is an important step to understand their role in aquatic ecosystems. This study was to determine bacterial diversity and their physiological characters of bacteria from Bandealit Coast in Jember East Java Indonesia. The bacteria were confirmed by BOX-PCR profile for their genetic polymorphisms. Identification of potential isolate was conducted based on 16S rRNA gene sequence. The result showed that BA011109 isolate was able to utilize D-cellobiose as a sole substrate, indicating its ability to hydrolyse -glucoside bond. This isolate was a potential decomposer in the area considering that most of organic pollutants were from plants that cointain high cellulose. Based on its 16S rRNA gene sequence, this isolate was closely related to Microbacterium esteraromaticum with 100% homology. Further study on quantitative hydrolytic activities is needed to elucidate its role as an organic matter decomposer in aquatic environment.

  7. Therapeutic efficacy of Lactobacillus acidophilus against bacterial isolates from burn wounds

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    Mohammed Sh. Jebur

    2010-12-01

    Full Text Available Background: Probiotics are live microorganisms which are mainly strains of Lactobacillus spp., Bifidobacterium spp. When administered in adequate amounts, these microorganisms offer a health benefit for the host. Probiotic organisms are also available commercially in milk, sour milk, ice cream and other foods. Aims: To identify bacterial species isolated from burn wounds, and also to evaluate (In-vitro the therapeutic efficacy of Lacto. acidophilus against these bacterial isolates. To compare this activity to other antibacterial agents which are used medically in the treatment of burn wound cases. Materials and Methods: Burn wound swabs were obtained from 50 patients who had been admitted to hospitals in Baghdad during August to November 2009. These swabs were inoculated onto enriched and differential culture media. Subcultures were performed on selective media. The necessary biochemical tests were conducted and the organisms identified using standard procedures. Susceptibility of isolated pathogens to local isolates Lacto. Acidophilus (with 1х108 cells/mL and 10 commonly used burn wounds antibiotics was examined using standard susceptibility testing. Results: Ninety different organisms were isolated. Gram-positive cocci accounted for 16 (17.7% and gram-negative bacilli for 74 (82.2% bacterial isolates. Pseudomonas aeruginosa 30(33.3% were the most commonly isolated organisms, followed by Escherichia coli, Enterobacter spp., Klebsiella spp., Proteus spp.(22.2,20,4.4,2.2%, respectively. Staphylococcus aureus isolates were performed in 8(8.8%. However, the incidence of Staphylococcus epidermidis was 2 (2.2%, while ß-haemolytic Streptococci was 4(4.4%. In susceptibility testing, Lacto. acidophilus had coverage against 90 (100% of 74 gram-negative and 16 of gram-positive bacteria tested. The coverage of the remaining 10 antibacterial agents used was different in their activity (resistance or sensitivity, which ranged between 50-100%. Conclusion

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

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    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

  9. Antioxidant treatments counteract the non-culturability of bacterial endophytes isolated from legume nodules.

    Science.gov (United States)

    Muresu, Rosella; Tondello, Alessandra; Polone, Elisa; Sulas, Leonardo; Baldan, Barbara; Squartini, Andrea

    2013-06-01

    In many wild legumes, attempts to cultivate nodule bacteria fail. We hypothesized that the limited culturability could be related to injury from oxidative stress caused by disruption of plant tissues during isolation. To test that, we isolated bacteria from nodules of Hedysarum spinosissimum and Tetragonolobus purpureus using buffers supplemented with scavenging systems to prevent damage from reactive oxygen species (ROS). Treatments included the following: antioxidants (glutathione, ascorbate, EDTA) or enzymes (catalase, peroxidase, superoxide dismutase), tested either as modified squashing buffers or added in plates. Some combinations yielded dramatic increases of culturability. Different endophytes were found, including additional Rhizobiaceae that were not the primary symbiont and were unable to nodulate. Their H2O2 tolerance in broth culture showed differences consistent with the unequal culturability observed. In wild legumes species, ROS generation during extraction appears to be a major factor limiting microbiota isolation, and protocols presented here significantly improve the recovery of culturable bacterial endophytes from plants.

  10. Gardnerella vaginalis isolated from patients with bacterial vaginosis and from patients with healthy vaginal ecosystems.

    Science.gov (United States)

    Aroutcheva, A A; Simoes, J A; Behbakht, K; Faro, S

    2001-10-01

    The differences in the phenotype and genotype of Gardnerella vaginalis isolates from patients with bacterial vaginosis (BV) and from patients without BV are unknown. In our study, 43 isolates of G. vaginalis were examined for biotype (hippurate hydrolysis, lipase, and beta-galactosidase activity), sensitivity to metronidazole, and genotype. Of the 117 women visiting the gynecology clinic at Rush-Presbyterian-St. Luke's Medical Center who were included in the study, 27.4% were found to have BV. G. vaginalis was found in samples from 87.5% of women with BV, from 34.0% of women with intermediate BV, and from 26.4% of women with healthy vaginal ecosystems. Among patients with G. vaginalis, biotypes 7 and 8 were isolated from 32% and 20% of patients, respectively. Biotype 5 was predominantly associated with a healthy vaginal ecosystem (P=.0004). Biotypes 5 and 7 were the most resistant to metronidazole. No specific phenotype or genotype of G. vaginalis causes BV.

  11. Production and characterization of bacterial cellulose by Leifsonia sp. CBNU-EW3 isolated from the earthworm, Eisenia fetida

    Science.gov (United States)

    A total of five bacterial strains were isolated from earthworm, Eisenia fetida and examined for bacterial cellulose (BC) production in Hestrin–Schramm medium (HS). Among the five strains tested, CBNU-EW3 exhibited excellent BC production and was identified as Leifsonia sp. by 16S rDNA sequence analy...

  12. Genome Sequences of 15 Gardnerella vaginalis Strains Isolated from the Vaginas of Women with and without Bacterial Vaginosis

    Science.gov (United States)

    Robinson, Lloyd S.; Perry, Justin; Lek, Sai; Wollam, Aye; Sodergren, Erica; Weinstock, George

    2016-01-01

    Gardnerella vaginalis is a predominant species in bacterial vaginosis, a dysbiosis of the vagina that is associated with adverse health outcomes, including preterm birth. Here, we present the draft genome sequences of 15 Gardnerella vaginalis strains (now available through BEI Resources) isolated from women with and without bacterial vaginosis. PMID:27688326

  13. Isolation and Characterization of Bacteriophages Against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit.

    Science.gov (United States)

    Yu, Ji-Gang; Lim, Jeong-A; Song, Yu-Rim; Heu, Sunggi; Kim, Gyoung Hee; Koh, Young Jin; Oh, Chang-Sik

    2016-02-01

    Pseudomonas syringae pv. actinidiae causes bacterial canker disease in kiwifruit. Owing to the prohibition of agricultural antibiotic use in major kiwifruit-cultivating countries, alternative methods need to be developed to manage this disease. Bacteriophages are viruses that specifically infect target bacteria and have recently been reconsidered as potential biological control agents for bacterial pathogens owing to their specificity in terms of host range. In this study, we isolated bacteriophages against P. syringae pv. actinidiae from soils collected from kiwifruit orchards in Korea and selected seven bacteriophages for further characterization based on restriction enzyme digestion patterns of genomic DNA. Among the studied bacteriophages, two belong to the Myoviridae family and three belong to the Podoviridae family, based on morphology observed by transmission electron microscopy. The host range of the selected bacteriophages was confirmed using 18 strains of P. syringae pv. actinidiae, including the Psa2 and Psa3 groups, and some were also effective against other P. syringae pathovars. Lytic activity of the selected bacteriophages was sustained in vitro until 80 h, and their activity remained stable up to 50°C, at pH 11, and under UV-B light. These results indicate that the isolated bacteriophages are specific to P. syringae species and are resistant to various environmental factors, implying their potential use in control of bacterial canker disease in kiwifruits.

  14. Frequency of β-lactamase enzyme and antibiogram pattern in bacterial flora isolated from staffs hands

    Directory of Open Access Journals (Sweden)

    Shilla Jalalpoor

    2011-12-01

    Full Text Available Background: β-lactamase is an enzyme that can inactivate β–Lactam family antibiotics. High prevalence of β-lactamase producer bacteria on the staff hands, due to antibiotic resistance and nosocomial infection in hospitalized patients. The objective of this study was to assess the frequency of β-lactamase positive bacteria and antibiogram pattern in bacterial flora isolated from staff hands of the Al-Zahra hospital in Isfahan.Materials and Method: This laboratory research was performed during of 2005-2007 in Al-Zahra hospital in Isfahan. According to statistical formula, we randomly selected 80 samples from staff hands. Staff hand samples collected with finger print method. Bacterial identification was performed with microbiological methods and β–lactamase production was performed with Acidometric method and antibiogram pattern was performed with Kirby Bauer method.Results: According to the acidometric test results of 80 isolated staff hands, 61.85% of strains produce β–lactamase. Staphylococcus spp., Bacillus spp. and Enterobacteriaceae were the most important producers respectively (70.83%, 64.72% and 50%. According to antibiogram test results, penicillin and vancomycin had the highest and lowest resistance. Conclusion: High frequency of β–lactamase in bacterial survey represents colonization of bacteria in staff hands; may be due to facility transmission β–lactamase plasmid genes in bacteria. We suggest better hand washing in hospitals and prescription of β–lactame antibiotics was based only on antibiogram results

  15. Isolation and characterization of culturable seed-associated bacterial endophytes from gnotobiotically grown Marama bean seedlings.

    Science.gov (United States)

    Chimwamurombe, Percy Maruwa; Grönemeyer, Jann Lasse; Reinhold-Hurek, Barbara

    2016-06-01

    Marama bean (Tylosema esculentum) is an indigenous non-nodulating legume to the arid agro-ecological parts of Southern Africa. It is a staple food for the Khoisan and Bantu people from these areas. It is intriguing how it is able to synthesize the high-protein content in the seeds since its natural habitat is nitrogen deficient. The aim of the study was to determine the presence of seed transmittable bacterial endophytes that may have growth promoting effects, which may be particularly important for the harsh conditions. Marama bean seeds were surface sterilized and gnotobiotically grown to 2 weeks old seedlings. From surface-sterilized shoots and roots, 123 distinct bacterial isolates were cultured using three media, and identified by BOX-PCR fingerprinting and sequence analyses of the 16S rRNA and nifH genes. Phylogenetic analyses of 73 putative endophytes assigned them to bacterial species from 14 genera including Proteobacteria (Rhizobium, Massilia, Kosakonia, Pseudorhodoferax, Caulobacter, Pantoea, Sphingomonas, Burkholderia, Methylobacterium), Firmicutes (Bacillus), Actinobacteria (Curtobacterium, Microbacterium) and Bacteroidetes (Mucilaginibacter, Chitinophaga). Screening for plant growth-promoting activities revealed that the isolates showed production of IAA, ACC deaminase, siderophores, endoglucanase, protease, AHLs and capacities to solubilize phosphate and fix nitrogen. This is the first report that marama bean seeds may harbor endophytes that can be cultivated from seedlings; in this community of bacteria, physiological characteristics that are potentially plant growth promoting are widespread.

  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. Co-production of two new peptide antibiotics by a bacterial isolate Paenibacillus alvei NP75.

    Science.gov (United States)

    Anandaraj, Balaiah; Vellaichamy, Adaikkalam; Kachman, Maureen; Selvamanikandan, Athinarayanan; Pegu, Shyamanta; Murugan, Vadivel

    2009-02-06

    Two new peptide antibiotics were secreted by a Gram-positive bacterial strain isolated from fermented tomato fruit. Based on its 99% 16S rDNA sequence similarity with Paenibacillus alvei, the isolate was designated as P. alvei NP75. Among these two peptides, one is active against Gram-positive pathogens while the other against Gram-negative pathogens; thus these peptides were named as paenibacillin P and paenibacillin N, respectively. After the purification of those peptide antibiotics from the cell free culture supernatant by RP-HPLC, they were analyzed for their temperature sensitivity and susceptibility to proteases. Higher-temperature tolerant paenibacillin N was easily degraded by proteinase K, while the temperature sensitive paenibacillin P was not affected by any of the proteases used in this study other than a specific protease that was secreted by the same NP75 strain. Mass-spectrometry analysis of the above peptide antibiotics further confirmed their distinction among the known peptide antibiotics. We are reporting first of its kind the co-production of two different new peptide antibiotics from a single bacterial isolate of P. alvei strain.

  18. 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%.

  19. Isolation of bacteria causing secondary bacterial infection in the lesions of cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Ziaie Hengameh

    2008-01-01

    Full Text Available Background: Cutaneous Leishmaniasis (CL is a parasitic disease characterized by single or multiple ulcerations. Secondary bacterial infection is one of the complications of the disease that can increase the tissue destruction and the resulting scar. Objective: To effectively determine the incidence of real secondary bacteria infection in cutaneous leishmaniasis, we designed the current study. Methods and Materials: This was a cross-sectional study performed in Skin Diseases and Leishmaniasis Research Centre, Isfahan, Iran. In this study, 854 patients with confirmed CL were enrolled. Samples were taken from all the patients. Sterile swaps were achieved for the ulcer exudates and scraping was used for nonulcerated lesions. All the samples were transferred to tryptic soy broth medium. After 24 h of incubation in 37°C, they were transferred to eosin methylene blue agar (EBM and blood agar. Laboratory tests were used to determine the species of bacteria. All of the collected data were analyzed by SPSS software and chi-square. Results: Among 854 patients with confirmed cutaneous leishmaniasis, 177 patients (20.7% had positive cultures for secondary bacterial infection. Bacteria isolated from the lesions were as follows: Staphylococcus aureus - 123 cases (69.4%, coagulase negative Staphylococcus - 41 cases (23.1%, E. coil - 7 cases (3.9%, Proteus - 3 cases (1.7% and Klebsiella - 3 cases (1.7%. Conclusions: The incidence of secondary bacterial infection in lesions of CL was 20.7%. The most common isolated pathogen was Staphylococcus aureus . The incidence of secondary bacterial infection was significantly more in the ulcerated lesions as compared with nonulcerated lesions ( P = 0.00001.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. Highly effective bacterial agents against Cimbex quadrimaculatus (Hymenoptera: Cimbicidae): isolation of bacteria and their insecticidal activities.

    Science.gov (United States)

    Cakici, Filiz Ozkan; Ozgen, İnanc; Bolu, Halil; Erbas, Zeynep; Demirbağ, Zihni; Demir, İsmail

    2015-01-01

    Cimbex quadrimaculatus (Hymenoptera: Cimbicidae) is one of the serious pests of almonds in Turkey and worldwide. Since there is no effective control application against this pest, it has been a serious problem up to now. Therefore, we aimed to find an effective bacterium that can be utilized as a biocontrol agent against C. quadrimaculatus in pest management. We isolated seven bacteria from dead and live C. quadrimaculatus larvae, and evaluated the larvicidal potency of all isolates on the respective pest. Based on the morphological, physiological, biochemical and molecular properties (partial sequence of 16S rRNA gene), the isolates were identified to be Bacillus safensis (CQ1), Bacillus subtilis (CQ2), Bacillus tequilensis (CQ3), Enterobacter sp. (CQ4), Kurthia gibsonii (CQ5), Staphylococcus sp. (CQ6) and Staphylococcus sciuri (CQ7). The results of the larvicidal activities of these isolates indicated that the mortality value obtained from all treatments changed from 58 to 100 %, and reached 100 % with B. safensis (CQ1) and B. subtilis (CQ2) on the 3rd instar larvae within 10 days of application of 1.89 × 10(9) cfu/mL bacterial concentration at 25 °C under laboratory conditions. Findings from this study indicate that these isolates appear to be a promising biocontrol agent for C. quadrimaculatus.

  2. Prevalence and antibiogram of bacterial isolates from urinary tract infections at Dessie Health Research Laboratory, Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Mulugeta Kibret; Bayeh Abera

    2014-01-01

    Objective: To determine the prevalence and antimicrobial susceptibility of bacteria from suspected urinary tract infections.Methods:A retrospective analysis of bacterial pathogens and their antimicrobial susceptibility was done on urine samples at Dessie Regional Laboratory in the period 2003 to 2010. Antimicrobial susceptibility tests were done using disc diffusion technique as per the standard of Kirby-Bauer method.Results:The male to female ratio of the patients was 1:1.96. Of the total 1404 samples, 319 (22.7%) were culture positive. Escherichia coli was the dominant isolate (63.6%) followed by Klebsiella spp. (8.5%) and Proteus spp. (8.2%). The overall resistance rates to erythromycin, amoxycillin, and tetracycline were 85.6%, 88.9% and 76.7%, respectively. The three most frequently isolated bacteria had resistance rates of 80.1%-90.0% to, amoxycillin, and tetracycline and sensitivity rates of 0 to 25% to nitrofurantoin, ciprofloxacin and gentamicin. Antibiogram of isolates showed that 152 (47.85%) isolates were resistance to two and more antimicrobials.Conclusions:In the study area resistance rates to erythromycin, amoxycillin and tetracycline were high. Since most isolates were sensitive to nitrofurantoin and gentamicin, they are considered as appropriate antimicrobials for empirical treatment urinary tract infections.

  3. 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)

  4. A case report of acute pediatric bacterial meningitis due to the rare isolate, Pseudomonas putida

    Institute of Scientific and Technical Information of China (English)

    Grishma V. Kulkarni

    2016-01-01

    Acute bacterial meningitis (ABM) is the medical emergency which warrants an early diagnosis and an aggressive therapy. Despite the availability of the potent newer antibiotics, the mortality caused by ABM and its complications remain high in India, ranging from 16% to 32%. The aim of this case report is to present the rare isolation ofPseudomonas putida from cerebrospinal lfuid sample. Besides this, the author also emphasizes the importance of correctly identifying the organism and thus the selection of the most accurate antibiotic from the susceptibility proifle to allow for early recovery and to improve the patient outcome and survival.

  5. 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.

  6. Isolation of bacterial cellulose nanocrystalline from pineapple peel waste: Optimization of acid concentration in the hydrolysis method

    Science.gov (United States)

    Anwar, Budiman; Rosyid, Nurul Huda; Effendi, Devi Bentia; Nandiyanto, Asep Bayu Dani; Mudzakir, Ahmad; Hidayat, Topik

    2016-02-01

    Isolation of needle-shaped bacterial cellulose nanocrystalline with a diameter of 16-64 nm, a fiber length of 258-806 nm, and a degree of crystallinity of 64% from pineapple peel waste using an acid hydrolysis process was investigated. Experimental showed that selective concentration of acid played important roles in isolating the bacterial cellulose nanocrystalline from the cellulose source. To achieve the successful isolation of bacterial cellulose nanocrystalline, various acid concentrations were tested. To confirm the effect of acid concentration on the successful isolation process, the reaction conditions were fixed at a temperature of 50°C, a hydrolysis time of 30 minutes, and a bacterial cellulose-to-acid ratio of 1:50. Pineapple peel waste was used as a model for a cellulose source because to the best of our knowledge, there is no report on the use of this raw material for producing bacterial cellulose nanocrystalline. In fact, this material can be used as an alternative for ecofriendly and cost-free cellulose sources. Therefore, understanding in how to isolate bacterial cellulose nanocrystalline from pineapple peel waste has the potential for large-scale production of inexpensive cellulose nanocrystalline.

  7. Isolation and Partial Characterization of Bacterial Strains on Low Organic Carbon Medium from Soils Fertilized with Different Organic Amendments

    NARCIS (Netherlands)

    Senechkin, I.V.; Speksnijder, A.G.C.L.; Semenov, A.M.; Bruggen, van A.H.C.; Overbeek, van L.S.

    2010-01-01

    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 mu g C ml(-1)) traditionally used for isolation of oligotrophs. Organic amendments in combination with field history resulted in differences in diss

  8. In vitro antimicrobial activity of marbofloxacin and enrofloxacin against bacterial strains isolated from companion animals.

    Science.gov (United States)

    Farca, A M; Cavana, P; Robino, P; Nebbia, P

    2007-06-01

    Fluoroquinolones were originally developed for the Gram-negative aerobic spectrum, but the newer generation agents are also highly effective against some Gram-positive pathogens and cause few adverse effects. Owing to these characteristics, fluoroquinolones are often used in first line therapy in small animal practice. However, their widespread use has raised concern over emerging bacterial resistance. In this study we evaluated the in vitro efficacy of two fluoroquinolones, marbofloxacin and enrofloxacin, on field strains isolated from clinical infections between 2002 and 2005. Our data show that most of the isolates are still sensitive to both antimicrobials and marbofloxacin was more effective than enrofloxacin, especially against P. aeruginosa and beta-Streptococci (P < 0.01). beta-Streptococci demonstrated the greatest resistance to the two study drugs.

  9. Isolation and characteristics of a novel biphenyl-degrading bacterial strain, Dyella ginsengisoli LA-4

    Institute of Scientific and Technical Information of China (English)

    LI Ang; QU Yuanyuan; ZHOU Jiti; GOU Min

    2009-01-01

    A novel biphenyl-degrading bacterial strain LA-4 was isolated from activated sludge. It was identified as Dyella ginsengisoli according to phylogenetic similarity of 16S rRNA gene sequence. This isolate could utilize biphenyl as sole source of carbon and energy, which degraded over 95 mg/L biphenyl within 36 h. The major metabolites formed from biphenyl, such as 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) and benzoic acid, were identified by LC-MS. The crude cell extract of strain LA-4 exhibited the activity of 2,3-dihydroxybiphenyl 1,2-dioxygenase (2,3-DHBD) and the kinetic parameters were Km= 26.48 μmol/L and Vmax= 8.12 μmol/mg protein. A conserved region of the biphenyl dioxygenase gene bphA1 of strain LA-4 was amplified by PCR and confirmed by DNA sequencing.

  10. Isolation, screening and molecular identification of novel bacterial strain removing methylene blue from water solutions

    Science.gov (United States)

    Kilany, Mona

    2017-04-01

    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.

  11. 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

    that Danish bacterial isolates from livestock so far have not or have only to a limited degree developed resistance to antimicrobial compounds commonly used for disinfection. Acquired copper resistance was only found in enterococci. There were large differences in the intrinsic susceptibility of the different......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...... of susceptibilities to the different antimicrobial agents. Large variations were observed in the susceptibility of the different bacterial species to the different compounds. Staphylococci were in general very susceptible to all antimicrobial compounds tested. The Salmonella isolates were in general less susceptible...

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

    Science.gov (United States)

    Rajasekar, Aruliah; Anandkumar, Balakrishnan; Maruthamuthu, Sundaram; Ting, Yen-Peng; Rahman, Pattanathu K S M

    2010-01-01

    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.

  13. Isolation, cultivation, purification and identification of bacterial species from microfauna of soil

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    Amna Ali

    2011-03-01

    Full Text Available

     

    Abstract:
    Soil is an excellent source of unknown microorganisms since bacteria, algae, protozoans, yeasts, moulds, and microscopic worms are routinely found in this environment. Therefore, soil is a medium in which life is sustained in a fragile biological balance. Bacteria play an important role in nutritional chains that are an important part of biological balance. In the present study, four different soil samples were collected from the rhizosphere of i Sapota zapotilla, ii Eucalyptus species, iii Ficus religiosa from Lahore and iv soil from Changa manga, Pakistan. A Total of 28 bacterial species were isolated and classified in the period between November 2008 and December 2009. All species were cultured on recommended media for verification of biochemical characteristics. The results showed that at least fifteen Gram-positive bacterial species were present in samples and these were considered as the major group constituting the bacterial population strains

  14. 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.)

  15. Biodegradation of the metallic carcinogen hexavalent chromium Cr(VI by an indigenously isolated bacterial strain

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    Das Alok

    2010-01-01

    Full Text Available Background : Hexavalent chromium [Cr(VI], a potential mutagen and carcinogen, is regularly introduced into the environment through diverse anthropogenic activities, including electroplating, leather tanning, and pigment manufacturing. Human exposure to this toxic metal ion not only causes potential human health hazards but also affects other life forms. The World Health Organization, the International Agency for Research on Cancer, and the Environmental Protection Agency have determined that Cr(VI compounds are known human carcinogens. The Sukinda valley in Jajpur District, Orissa, is known for its deposit of chromite ore, producing nearly 98% of the chromite ore in India and one of the prime open cast chromite ore mines in the world (CES, Orissa Newsletter. Materials and Methods: Our investigation involved microbial remediation of Cr(VI without producing any byproduct. Bacterial cultures tolerating high concentrations of Cr were isolated from the soil sample collected from the chromite-contaminated sites of Sukinda, and their bioaccumulation properties were investigated. Strains capable of growing at 250 mg/L Cr(VI were considered as Cr resistant. Results: The experimental investigation showed the maximum specific Cr uptake at pH 7 and temperature 30oC. At about 50 mg/L initial Cr(VI concentrations, uptake of the selected potential strain exceeded 98% within 12 h of incubation. The bacterial isolate was identified by 16S rRNA sequencing as Brevebacterium casei. Conclusion: Results indicated promising approach for microbial remediation of effluents containing elevated levels of Cr(VI.

  16. Characterization of Bacterial Strains Isolated from a Novel Seawater-based Retting Treatment of Hemp

    Institute of Scientific and Technical Information of China (English)

    ZHU Run-ye; CHEN Jian-yong; FENG Xin-xing; ZHANG Jian-chun

    2008-01-01

    Cultivable bacteria were isolated from seawater-based retting treatment of hemp, in which three of purified strains (SW - 1, SW - 2, and S - SW1) produced relatively high levels of pectinase activities, and also produced mannanases and xylanases.PCR - based entebacterial repetitive intergenic consensus primers (ERIC- PCR) were employed for fingerprinting DNA of the bacterial strains.The ERIC - PCR fingerprints of stains SW- 1, SW -1, and S -SW1 were found to be different, and should be further identified for each isolate.Strains SW - 1 and SW - 2 were identified as Stenotrophomnas maltophilia, while strain S - SW1 was assigned to Ochrobactrum anthropi by BIOLOG system.These two species represented rhizosphere bacterial genera, and possibly were introduced by the hemp plants.These organisms seemed potentially capable of producing pectinase and hemicellulase, and thus effectively degrading the gum substances in the seawater retting.This research could be helpful for improving a novel seawater-based retting treatment of hemp.

  17. Enzymatic activity of endophytic bacterial isolates of Jacaranda decurrens Cham. (Carobinha-do-campo

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    Aysha Jussara Ivonilde Carrim

    2006-05-01

    Full Text Available The objectives of this work was to isolate endophytic bacteria from Jacaranda decurrens Cham. and screening of some enzymes of biotechnological interest. Ten (10 bacterial species were isolated and identified from the leaves and steams. All the isolates presented enzymatic activity, which was ranked as follows: proteolytic (60% and amilolytic activity (60%, lipolytic (40%, esterasic (40%. However, cellulolytic and pectinolytic activities were not detected. This is the first report on the isolation and identification of endophytic bacteria from Jacaranda decurrens Cham.O objetivo deste trabalho foi isolar bactérias endofíticas de Jacaranda decurrens Cham. e selecionar algumas enzimas de interesse biotecnológico. Dez espécies de bactérias foram isoladas e identificadas de caule e folhas. Todos os isolados de apresentaram atividade enzimática, e a maior predominância foi de atividade proteolítica (60% e atividade amilolítica (60%, seguidas atividades lipolítica (40% e esterásica (40%. Contudo, as atividades celulolítica e pectinolítica não foram detectadas. Este é o primeiro relato de isolamento e identificação de bactérias presentes em Jacaranda decurrens Cham.

  18. Genetic and biochemical diversity of Gardnerella vaginalis strains isolated from women with bacterial vaginosis.

    Science.gov (United States)

    Pleckaityte, Milda; Janulaitiene, Migle; Lasickiene, Rita; Zvirbliene, Aurelija

    2012-06-01

    Gardnerella vaginalis is considered a substantial player in the progression of bacterial vaginosis (BV). We analysed 17 G. vaginalis strains isolated from the genital tract of women diagnosed with BV to establish a potential link between genotypes/biotypes and the expression of virulence factors, vaginolysin (VLY) and sialidase, which are assumed to play a substantial role in the pathogenesis of BV. Amplified ribosomal DNA restriction analysis revealed two G. vaginalis genotypes. Gardnerella vaginalis isolates of genotype 2 appeared more complex than genotype 1 and were subdivided into three subtypes. Biochemical typing allowed us to distinguish four different biotypes. A great diversity of the level of VLY production among the isolates of G. vaginalis may be related to a different cytotoxicity level of the strains. We did not find any correlation between VLY production level and G. vaginalis genotype/biotype. In contrast, a link between G. vaginalis genotype and sialidase production was established. Our findings on the diversity of VLY expression level in different clinical isolates and linking sialidase activity with the genotype of G. vaginalis could help to evaluate the pathogenic potential of different G. vaginalis strains.

  19. Antagonistic interactions between endophytic cultivable bacterial communities isolated from the medicinal plant Echinacea purpurea.

    Science.gov (United States)

    Maida, Isabel; Chiellini, Carolina; Mengoni, Alessio; Bosi, Emanuele; Firenzuoli, Fabio; Fondi, Marco; Fani, Renato

    2016-09-01

    In this work we have studied the antagonistic interactions existing among cultivable bacteria isolated from three ecological niches (rhizospheric soil, roots and stem/leaves) of the traditional natural medicinal plant Echinacea purpurea. The three compartments harboured different taxonomic assemblages of strains, which were previously reported to display different antibiotic resistance patterns, suggesting the presence of differential selective pressure due to antagonistic molecules in the three compartments. Antagonistic interactions were assayed by the cross-streak method and interpreted using a network-based analysis. In particular 'within-niche inhibition' and 'cross-niche inhibition' were evaluated among isolates associated with each compartment as well as between isolates retrieved from the three different compartments respectively. Data obtained indicated that bacteria isolated from the stem/leaves compartment were much more sensitive to the antagonistic activity than bacteria from roots and rhizospheric soil. Moreover, both the taxonomical position and the ecological niche might influence the antagonistic ability/sensitivity of different strains. Antagonism could play a significant role in contributing to the differentiation and structuring of plant-associated bacterial communities. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  20. 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

  1. In vitro evaluation of Pseudomonas bacterial isolates from rice phylloplane for biocontrol of Rhizoctonia solani and plant growth promoting traits.

    Science.gov (United States)

    Akter, Shamima; Kadir, Jugah; Juraimi, Abdul Shukor; Saud, Halimi Mohd

    2016-07-01

    The ability for biocontrol and plant growth promotion of three Pseudomonas bacterial isolates namely Pseudomonas fluorescens (UMB20), Pseudomonas aeruginosa (KMB25) and Pseudomonas asplenii (BMB42) obtained from rice plants was investigated. Fungal growth inhibition by the isolates ranged from 86.85 to 93.15% in volatile and 100% in diffusible metabolites test. Among the isolates, BMB42 showed fungal growth inhibition significantly in the volatile metabolite test. Isolates UMB20 and BMB42 were able to synthesis chitinase with chitinolytic indices of 13.66 and 13.50, respectively. In case of -1,3-glucanase, all the isolates showed activity to produce this enzyme at varied levels and isolate KMB25 showed significantly highest activity (53.53 ppm). Among the three isolates, KMB25 showed positive response to protease production and all of them were negative to pectinase and lipase and positive to the production of siderophore, and HCN, and were able to solubilize tricalcium phosphate. All the three bacterial isolates were capable of forming biofilm at different levels. Above results suggest that phylloplane Pseudomonas bacterial isolates have potential for antifungal activities and plant growth promotion.

  2. Epidemiological Aspect and common Bacterial and Fungal isolates from Suppurative Corneal Ulcer in Mymensingh Region.

    Science.gov (United States)

    Moid, M A; Akhanda, A H; Islam, S; Halder, S K; Islam, R

    2015-04-01

    This prospective study was done to find out the epidemiological factors of suppurative corneal ulcer and the common causative bacterial and fungal isolates from the, patients with suppurative corneal ulcer in secondary and tertiary level hospital at Mymensingh region. A total 100 samples of corneal scrapings were collected purposively from clinically diagnosed suppurative corneal ulcer patients from March 18, 2012 to March 17, 2013. Out of the total 100 samples, bacterial species were 29(29%) cases and the fungal spacies were 71(71%) identified by the culture in blood agar, chocolate agar and sabouraud's agar media and also by microscopic examination. The bacterial species were streptococcus pneumonae 12 cases (12%), Staphylococcus aureus 9 cases (9%), pseudomonas in 6 cases (6%), and Streptococcus pyoganes 2 cases (2%). Fungal species were aspergillus fumigatus 61 cases (61%), aspergillus niger 10 cases (10%). Out of the study populations, most of the populations were from the age group of 41 to 60 years (39 %), followed 21 to 40 years (34%) age group. Considering the sex, male were 67%, female were 33%. The majority of patients came from the rural area of Mymensingh region; occupationally they were farmers (44%). Ocular trauma due to agricultural materials was the most common associated factor (71%). The etiological and epidemiological pattern of suppurative corneal ulcer varies significantly with geographical region, patient population and health of the cornea. The present study was carried out to explore the epidemiological pattern, causative bacterial and fungal specie by laboratory procedure from corneal scraping and to invent a prospective guide line for the management of corneal ulcer in the community.

  3. 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

  4. ISOLATION AND CHARACTERIZATION OF BIFENTHRIN CATABOLIZING BACTERIAL STRAIN BACILLUS CIBI FROM SOIL FOR PYRETHROIDS BIODEGRADATION

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    Preeti Pandey

    2014-01-01

    Full Text Available Pyrethroids are commonly used in most parts of the world and are reported to have potential health risks. Bifenthrin, a third generation pyrethroid used as insecticide has caused potential effect on aquatic life and human health. Bioremediation is a practical approach to reduce pesticide in the environment and reports of microbial degradation of bifenthrin are meagre. This study was aimed at isolating and characterizing bacterial isolates for the efficient removal of bifenthrin residues in the environment. A bacterial strain PGS-4 isolated from sewage of pesticide industry was tested for growth at higher concentration of bifenthrin (800 mg L-1 and the optimum pH and temperature were determined. The strain utilized bifenthrin as sole carbon source for growth over a wide range of pH (4.0-9.0 and temperatures (16-37°C. On the basis of growth kinetics studies, the optimal conditions were determined to be pH 7.0-8.0 and 30°C. 16S rRNA gene sequence analysis showed that strain PGS-4 forms a distinct phylogenetic lineage within the evolutionary radiation encompassed by the genus Bacillus and showed 99% similarity to that of Bacillus cibi. This study depicts the ability of B. cibi to utilize bifenthrin at higher concentration under in vitro thereby can be used in eliminating bifenthrin from contaminated soils as a practical approach to reduce pyrethroid toxicity in the environment.

  5. 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.

  6. 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%.

  7. Bioremediation potential of a highly mercury resistant bacterial strain Sphingobium SA2 isolated from contaminated soil.

    Science.gov (United States)

    Mahbub, Khandaker Rayhan; Krishnan, Kannan; Megharaj, Mallavarapu; Naidu, Ravi

    2016-02-01

    A mercury resistant bacterial strain, SA2, was isolated from soil contaminated with mercury. The 16S rRNA gene sequence of this isolate showed 99% sequence similarity to the genera Sphingobium and Sphingomonas of α-proteobacteria group. However, the isolate formed a distinct phyletic line with the genus Sphingobium suggesting the strain belongs to Sphingobium sp. Toxicity studies indicated resistance to high levels of mercury with estimated EC50 values 4.5 mg L(-1) and 44.15 mg L(-1) and MIC values 5.1 mg L(-1) and 48.48 mg L(-1) in minimal and rich media, respectively. The strain SA2 was able to volatilize mercury by producing mercuric reductase enzyme which makes it potential candidate for remediating mercury. ICP-QQQ-MS analysis of Hg supplemented culture solutions confirmed that almost 79% mercury in the culture suspension was volatilized in 6 h. A very small amount of mercury was observed to accumulate in cell pellets which was also evident according to ESEM-EDX analysis. The mercuric reductase gene merA was amplified and sequenced. The deduced amino acid sequence demonstrated sequence homology with α-proteobacteria and Ascomycota group.

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

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    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.

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

    Science.gov (United States)

    Tedesco, Pietro; Maida, Isabel; Palma Esposito, Fortunato; Tortorella, Emiliana; Subko, Karolina; Ezeofor, Chidinma Christiana; Zhang, Ying; Tabudravu, Jioji; Jaspars, Marcel; Fani, Renato; de Pascale, Donatella

    2016-01-01

    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. PMID:27128927

  10. Biogenic amine producing capability of bacterial populations isolated during processing of different types of dry fermented sausages

    Directory of Open Access Journals (Sweden)

    M. Vincenzini

    2010-04-01

    Full Text Available In order to assess the distribution of the biogenic amine (BA producing capability within the bacterial populations occurring during production of dry fermented sausages, four different types of sausage processing, three with the use of starter cultures and one without, were investigated. All the main bacterial populations involved in the sausage processing showed a diffuse and strain dependent capability to produce BAs. However, quantitative determination of individual BAs produced by the bacterial isolates suggests an important role of enterococci in the accumulation of tyramine, the most abundant biogenic amine found in all investigated sausages.

  11. Isolation and Characterization of Gut Bacterial Proteases Involved in Inducing Pathogenicity of Bacillus thuringiensis Toxin in Cotton Bollworm, Helicoverpa armigera

    Science.gov (United States)

    Regode, Visweshwar; Kuruba, Sreeramulu; Mohammad, Akbar S.; Sharma, Hari C.

    2016-01-01

    Bacillus thuringiensis 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 toward pro-Cry1Ac. Among 12 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°C. Maximum inhibition of total proteolytic activity was exerted by phenylmethane sulfonyl fluoride 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 toward H. armigera. The gut bacterial isolates IVS1, IVS2, and IVS3 showed homology with B. thuringiensis (CP003763.1), Vibrio fischeri (CP000020.2), and Escherichia coli (CP011342.1), respectively. Proteases produced by midgut bacteria are involved in proteolytic processing of B. thuringiensis protoxin and play a major role in inducing pathogenicity of B. thuringiensis toxins in H. armigera. PMID:27766093

  12. 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.

  13. Antibacterial Activity of the Isolation Ethyl Acetate-Soluble Extract Noni Fruit (Morindra citrifolia L.) against Meat Bacterial Decay

    Science.gov (United States)

    Nugraheni, E. R.; Nurrakhman, M. B. E.; Munawaroh, H.; Saputri, L.

    2017-02-01

    Noni (Morindra citrifolia L.) is native to Indonesia which have medicinal properties. One of them as an antibacterial. This study aims to determine the antibacterial activity of isolates from the ethanol extract noni fruit to bacterial decay meat is Bacillus licheniformis, Klebsiella pneumonia, Bacillus alvei, Acinetobacter calcoaceticus, and Staphylococcus saprophyticus. The extraction process using the maceration method, and then made a partition by centrifugation ethyl acetate. Soluble part partition showed bacterial growth inhibition activity of the strong to very strong. Furthermore, the ethyl acetate soluble partition on preparative thin layer chromatography produced 5 isolates. Isolates obtained antibacterial activity test performed with a concentration of 20% and 30%. The results of antibacterial test against bacteria test isolates, showing isolates A can not inhibit the growth of bacteria, isolates B and C have medium activity and strong, isolates D and E isolates have activity against bacteria that were tested. MIC and MBC test results showed that the isolates B gives an inhibitory effect (bacteriostatic) against all bacteria. Content analysis of compounds by TLC using the reagents cerium (IV) sulfate indicates a phenol group. Isolates B contains a major compound which can be used as an antibacterial candidate in food preservation replace chemical preservatives.

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

    DEFF Research Database (Denmark)

    Hendriksen, Rene S.; Mevius, Dik J; Schroeter, Andreas

    2008-01-01

    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...... to the other bacterial species investigated. Conclusion: In general, isolates from Denmark, England (and Wales), the Netherlands, Norway, Sweden and Switzerland showed low frequencies of resistance, whereas many isolates from Belgium, France, Italy, Latvia and Spain were resistant to most antimicrobials tested...

  15. Isolation and characterization of a bacterial strain that efficiently degrades sex steroid hormones

    Institute of Scientific and Technical Information of China (English)

    JI Shulan; LIU Zhipei; LIU Zhipeng; REN Haiyan

    2007-01-01

    A bacterial strain,ZY3,growing on sex steroid hormones as the sole source of carbon and energy was isolated from the sewage treatment plant of a prophylactic steroids factory.ZY3 degrades the 3-methoxy-17β-hyclroxy-1,3,5(10),8(9)-δ-4-estren (MHE).This strain was preliminarily identified as Raoultella sp.ZY3 according to its morphology and its 16S rRNA gene sequence.During the experimental period (72 h),the optimum temperature,pH and 3-MHE concentration for the degradation of hydride by the strain ZY3 were 35℃,10 and 10 mg/L,respectively.The degradation rate of the sex steroid hormones increased to 87% and 85% after the addition of maltose and peptone,respectively.

  16. 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.

  17. Production of volatile aroma compounds by bacterial strains isolated from different surface-ripened French cheeses.

    Science.gov (United States)

    Deetae, Pawinee; Bonnarme, Pascal; Spinnler, Henry E; Helinck, Sandra

    2007-10-01

    Twelve bacterial strains belonging to eight taxonomic groups: Brevibacterium linens, Microbacterium foliorum, Arthrobacter arilaitensis, Staphylococcus cohnii, Staphylococcus equorum, Brachybacterium sp., Proteus vulgaris and Psychrobacter sp., isolated from different surface-ripened French cheeses, were investigated for their abilities to generate volatile aroma compounds. Out of 104 volatile compounds, 54 volatile compounds (identified using dynamic headspace technique coupled with gas chromatography-mass spectrometry [GC-MS]) appeared to be produced by the different bacteria on a casamino acid medium. Four out of eight species used in this study: B. linens, M. foliorum, P. vulgaris and Psychrobacter sp. showed a high flavouring potential. Among these four bacterial species, P. vulgaris had the greatest capacity to produce not only the widest varieties but also the highest quantities of volatile compounds having low olfactive thresholds such as sulphur compounds. Branched aldehydes, alcohols and esters were produced in large amounts by P. vulgaris and Psychrobacter sp. showing their capacity to breakdown the branched amino acids. This investigation shows that some common but rarely mentioned bacteria present on the surface of ripened cheeses could play a major role in cheese flavour formation and could be used to produce cheese flavours.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Liu, Bo; Luo, Jin; Li, Wei; Long, Xiu-Feng; Zhang, Yu-Qin; Zeng, Zhi-Gang; Tian, Yong-Qiang

    2016-01-01

    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).

  1. Antimicrobial susceptibility profiles of bacterial strains isolated from chronic apical periodontitis

    Directory of Open Access Journals (Sweden)

    Luminita Marutescu

    2013-12-01

    Full Text Available The aim of the present study is to investigate the microbiota of root filled teeth with apical periodontitis and to determine the antibiotic susceptibility patterns of microbial strains isolated from twenty nine apical lesion samples taken from patients with fibrous chronic apical lesions. The present study has highlighted the polymicrobial nature of the root canal infections and the importance of facultatively anaerobic, Gram positive bacteria found in 90.74% of the isolated microorganims. The present study has shown an increased resistance of microorganisms to conventional antibiotics, which included penicillin, erythromycin and amoxicillin, as well as tetracyclines, although the last ones have been used sparingly in the past decade. The results of antibiotic sensitivity obtained in this study underline the importance of the microbiological diagnosis and antibiotic susceptibility testing in the choice of therapeutic agents used for the treatment of chronic apical lesions. Further studies with clinical correlation of effectiveness of these antibiotics and cultures taken after administration of antibiotics as well as recording of disappearance of symptoms are also recommended.

  2. The resistance of bacterial isolates from spacecraft assembly cleanrooms against physical and chemical treatments

    Science.gov (United States)

    Rettberg, Petra; Kloss, Maria; Barczyk, Simon; Reitz, Guenther

    The COSPAR planetary protection guidelines define bioburden limits for spacecraft to protect solar system bodies from contamination by terrestrial life, and to protect Earth from possible life forms that may be returned from other solar system bodies. The cleaning and sterilisation methods to be selected for space hardware have to be as efficient as necessary to reach the maximal allowed bioburden limit. To be able to asses the suitability of different methods it is mandatory to investigate the physiological potential of the microbial isolates from cleanrooms. In the ESA project BioDiv the bioburden and biodiversity was determined in cleanrooms where the satellite Herschel was integrated and tested. From all bacterial isolates obtained in sev-eral measurement campaigns 30 strains were selected. Their resistance as vegetative cells was tested against different physical and chemical treatments: drying under ambient conditions, desiccation under defined relative humidity, vacuum exposure, UVC radiation exposure, freeze-thaw cycles under martian atmosphere and pressure, exposure to high and low pH values, and exposure to alcohols. The results of these tests can be summarised as follows: i) Most of the tested microorganisms from cleanrooms exhibit a certain resistance against one or more of the tested conditions. This is in contrast to strains which have already been cultured for long-periods in time under optimal laboratory conditions. They tend to loose their original resistance against different environmental parameters. ii) Different isolates from the same species can exhibit significantly different resistances. Therefore, the sole identification of microorgnisms by 16S rDNA sequencing does not give insights into their physiological potential. iii) The first hours of drying have a substantial inactiviation effect, longer periods of drying or even vacuum exposure reduce the surviving fraction only slightly more. iv) The sensitivity against UVC radiation varies

  3. Isolation of Bacterial Agents from the Lungs of Cattle with Pneumonia and Detection of Pasteurella Spp. by Polymerase Chain Reaction

    OpenAIRE

    KILIÇ, Ayşe; MUZ, Adile

    2004-01-01

    Lungs from 8222 cattle slaughtered at an abattoir in Elazığ were examined macroscopically, and pneumonia was detected in 500 (6.1%) lungs. These samples were inoculated onto blood agar supplemented with 7% sheep blood for isolation of bacterial agents. A polymerase chain reaction (PCR) based upon the use of species-specific primers was carried out on DNA samples extracted from suspected Pasteurella spp. isolates. In addition, a mouse inoculation test was carried out on suspected Pasteurella m...

  4. Uranium isotopic fractionation factors during U(VI) reduction by bacterial isolates

    Science.gov (United States)

    Basu, Anirban; Sanford, Robert A.; Johnson, Thomas M.; Lundstrom, Craig C.; Löffler, Frank E.

    2014-07-01

    We experimentally determined the magnitude of uranium isotopic fractionation induced by U(VI) reduction by metal reducing bacterial isolates. Our results indicate that microbial U(VI) reduction induces isotopic fractionation; heavier isotopes (i.e., 238U) partition into the solid U(IV) products. The magnitudes of isotopic fractionation (expressed as ε = 1000‰ * (α-1)) for 238U/235U were 0.68‰ ± 0.05‰ and 0.99‰ ± 0.12‰ for Geobacter sulfurreducens strain PCA and strain IFRC-N, respectively. The ε values for Anaeromyxobacter dehalogenans strain FRC-W, strain FRC-R5, a novel Shewanella isolate, and Desulfitobacterium sp. strain Viet1 were 0.72‰ ± 0.15‰, 0.99‰ ± 0.12‰, 0.96‰ ± 0.16‰ and 0.86‰ ± 0.06‰, respectively. Our results show that the maximum ε values of ∼1.0‰ were obtained with low biomass (∼107 cells/mL) and low electron donor concentrations (∼500 μM). These results provide an initial assessment of 238U/235U shifts induced by microbially-mediated U(VI) reduction, which is needed as 238U/235U data are increasingly applied as redox indicators in various geochemical settings.

  5. 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.

  6. Antibacterial and antifouling activities of chitosan/TiO2/Ag NPs nanocomposite films against packaged drinking water bacterial isolates.

    Science.gov (United States)

    Natarajan, Saravanan; Bhuvaneshwari, M; Lakshmi, D Shanthana; Mrudula, P; Chandrasekaran, N; Mukherjee, Amitava

    2016-10-01

    TiO2 and Ag NPs are widely used as antibacterial agents against many bacterial pathogens. Chitosan (polymer) itself acts as a strong antibacterial agent. Hence, chitosan/TiO2/Ag NPs incorporated nanocomposite film was prepared against packed drinking water bacterial strains. A concentration-dependent increase in the reduction of cell viability was observed in all the isolates under UV-C and dark exposure conditions. The bacteria consortium showed greater resistance against antibacterial effects of chitosan/TiO2/Ag nanocomposite as compared to single isolates. Glycocalyx test and mass assessment conclude the effective antibacterial activity by inhibiting bacterial adhesion on the film surface. The release of LDH and generation of ROS act as the predominant antibacterial mechanism induced by TiO2/Ag NPs. Surface characterization of chitosan/TiO2/Ag nanocomposite was studied by FTIR and XRD analyses and SEM analysis after interaction with the bacteria.

  7. ‘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.

  8. Molecular characterization of conjugative plasmids in pesticide tolerant and multi-resistant bacterial isolates from contaminated alluvial soil.

    Science.gov (United States)

    Anjum, Reshma; Grohmann, Elisabeth; Malik, Abdul

    2011-06-01

    A total of 35 bacteria from contaminated soil (cultivated fields) near pesticide industry from Chinhat, Lucknow, (India) were isolated and tested for their tolerance/resistance to pesticides, heavy metals and antibiotics. Bacterial isolates were identified by 16S rDNA sequencing. Gas Chromatography analysis of the soil samples revealed the presence of lindane at a concentration of 547 ng g(-1) and α-endosulfan and β-endosulfan of 422 ng g(-1) and 421 ng g(-1) respectively. Atomic Absorption Spectrophotometry analysis of the test sample was done and Cr, Zn, Ni, Fe, Cu and Cd were detected at concentrations of 36.2, 42.5, 43.2, 241, 13.3 and 11.20 mg kg(-1) respectively. Minimum inhibitory concentrations of all the isolates were determined for pesticides and heavy metals. All the multi-resistant/tolerant bacterial isolates were also tested for the presence of incompatibility (Inc) group IncP, IncN, IncW, IncQ plasmids and for rolling circle plasmids of the pMV158-family by PCR. Total community DNA was extracted from pesticide contaminated soil. PCR amplification of the bacterial isolates and soil DNA revealed the presence of IncP-specific sequences (trfA2 and oriT) which was confirmed by dot blot hybridization with RP4-derived DIG-labelled probes. Plasmids belonging to IncN, IncW and IncQ group were neither detected in the bacterial isolates nor in total soil DNA. The presence of conjugative or mobilizable IncP plasmids in the isolates indicate that these bacteria have gene transfer capacity with implications for dissemination of heavy metal and antibiotic resistance genes. We propose that IncP plasmids are mainly responsible for the spread of multi-resistant bacteria in the contaminated soils.

  9. Antimicrobial susceptibility testing of Gram-positive and -negative bacterial isolates directly from spiked blood culture media with Raman spectroscopy.

    Science.gov (United States)

    Dekter, H E; Orelio, C C; Morsink, M C; Tektas, S; Vis, B; Te Witt, R; van Leeuwen, W B

    2017-01-01

    Patients suffering from bacterial bloodstream infections have an increased risk of developing systematic inflammatory response syndrome (SIRS), which can result in rapid deterioration of the patients' health. Diagnostic methods for bacterial identification and antimicrobial susceptibility tests are time-consuming. The aim of this study was to investigate whether Raman spectroscopy would be able to rapidly provide an antimicrobial susceptibility profile from bacteria isolated directly from positive blood cultures. First, bacterial strains (n = 133) were inoculated in tryptic soy broth and incubated in the presence or absence of antibiotics for 5 h. Antimicrobial susceptibility profiles were analyzed by Raman spectroscopy. Subsequently, a selection of strains was isolated from blood cultures and analyzed similarly. VITEK®2 technology and broth dilution were used as the reference methods. Raman spectra from 67 antibiotic-susceptible strains showed discriminatory spectra in the absence or at low concentrations of antibiotics as compared to high antibiotic concentrations. For 66 antibiotic-resistant strains, no antimicrobial effect was observed on the bacterial Raman spectra. Full concordance with VITEK®2 data and broth dilution was obtained for the antibiotic-susceptible strains, 68 % and 98 %, respectively, for the resistant strains. Discriminative antimicrobial susceptibility testing (AST) profiles were obtained for all bacterial strains isolated from blood cultures, resulting in full concordance with the VITEK®2 data. It can be concluded that Raman spectroscopy is able to detect the antimicrobial susceptibility of bacterial species isolated from a positive blood culture bottle within 5 h. Although Raman spectroscopy is cheap and rapid, further optimization is required, to fulfill a great promise for future AST profiling technology development.

  10. Intracloacal inoculation, an effective screening method for determining the efficacy of probiotic bacterial isolates against Campylobacter colonization in broiler chickens.

    Science.gov (United States)

    Arsi, K; Donoghue, A M; Woo-Ming, A; Blore, P J; Donoghue, D J

    2015-01-01

    Campylobacter is a leading cause of foodborne illness worldwide. It is common in poultry, and human infections are often associated with consumption of contaminated poultry products. One strategy to reduce Campylobacter colonization in poultry is the use of oral probiotics, but this produces variable results, possibly because the probiotics are destroyed in the stomach's acidic environment. Protection (e.g., encapsulation) of isolates may overcome this problem, but there is no assurance that these isolates will have efficacy in the lower gastrointestinal tract. Therefore, screening candidate isolates by directly placing them in the lower intestinal tract via cloacal inoculation may eliminate the time and expense of encapsulating ineffective isolates. Thus, the purpose of this study was to collect bacterial isolates with anti-Campylobacter activity in vitro and evaluate their efficacy in vivo upon either oral or intracloacal administration. Bacterial isolates were collected from healthy birds and were evaluated for efficacy against C. jejuni in vitro. Isolates having generally regarded as safe status and demonstrating in vitro anti-Campylobacter properties were evaluated after oral or intracloacal inoculation into chicks on day 1 (n = 10 birds per isolate per route of administration). On day 7, birds were dosed by oral gavage with a four-strain mixture of wild-type Campylobacter containing at least 1 × 10(7) CFU/ml organisms. On day 14, birds were euthanized and the ceca were collected aseptically for Campylobacter enumeration. When dosed orally, only one isolate had a 1-log reduction in cecal Campylobacter counts, whereas when administered intracloacally, six of these isolates produced a 1- to 3-log reduction in cecal Campylobacter counts in 14-day-old chickens. These results support the strategy of evaluating the efficacy of potential probiotic isolates via cloacal inoculation prior to undergoing the effort of encapsulating isolates for oral administration.

  11. Analysis of the bacterial diversity existing on animal hide and wool: development of a preliminary PCR-restriction fragment length polymorphism fingerprint database for identifying isolates.

    Science.gov (United States)

    Chen, Yu; Gao, Hongwei; Zhang, Yanming; Deng, Mingjun; Wu, Zhenxing; Zhu, Laihua; Duan, Qing; Xu, Biao; Liang, Chengzhu; Yue, Zhiqin; Xiao, Xizhi

    2012-01-01

    Twenty-one bacterial strains were isolated from imported cattle hide and rabbit wool using two types of media, nutrient broth, and nutrient broth with serum. The bacteria identified were Brevibacillus laterosporus, Leclercia adecarboxylata, Peptococcus niger, Bacillus circulans, Raoultella ornithinolytica, Bacillus subtilis, Bacillus cereus, Bacillus thermobacillus, Bacillus choshinensis, Bacillus sphaericus, Acinetobacter haemolyticus, Sphingomonas paucimobilis, Bacillus thuringiensis, Staphylococcus intermedius, Mycobacteria, Moraxella, Klebsiella pneumoniae, Ralstonia pickettii, Staphylococcus chromogenes, Comamonas testosteroni, and Cupriavidus pauculus. The 16s rDNA gene of each bacterium was amplified using the universal primers 27f and 1492r. The amplicons were digested with AvaI, BamHI, BgII, DraI, EcoRI, EcoRV, HindIII, HinfI, HpaI, PstI, SmaI, TaqII, XbaI, XmaI, AluI, XhoI, and PvuI individually. A specific fingerprint from the PCR-restriction fragment length polymorphism method based on 16s rDNA was obtained for each bacterium. The results showed that the method developed was useful not only for bacterial identification but also for the etiological investigation of pathogens in imported animal hair and wool.

  12. Isolation and Characterization of a Thermophilic Oil-Degrading Bacterial Consortium

    Institute of Scientific and Technical Information of China (English)

    Gu Guizhou; Li Zheng; Zhao Dongfeng; Zhao Chaocheng

    2013-01-01

    In this study, a thermophilic oil-degrading bacterial consortium KO8-2 growing within the temperature range of 45-65℃(with 55℃being the optimum temperature) was isolated from oil-contaminated soil of Karamay in Xinjiang, China. Denaturing gradient gel electrophoresis (DGGE) showed that there were nine strains included in KO8-2, which originated from the genera of Bacillus, Geobacillus and Clostridium. They all belonged to thermophilic bacteria, and had been previously proved as degraders of at least one petroleum fraction. The crude oil degraded by KO8-2 was analyzed by infrared spectrophotometry, hydrocarbon group type analysis and gas chromatography. The results indicated that the bacterial consortium KO8-2 was able to utilize 64.33%of saturates, 27.06%of aromatics, 13.24%of resins and the oil removal efifciency reached up to 58.73%at 55℃when the oil concentration was 10 g/L. Detailed analysis showed that KO8-2 was able to utilize the hydrocarbon components before C19, and the n-alkanes ranging from C20-C33 were signiif-cantly degraded. The ratios of nC17/Pr and nC18/Ph were 3.12 and 3.87, respectively, before degradation, whereas after degradation the ratios reduced to 0.21 and 0.38, respectively. Compared with the control sample, the oil removal efifciency in KO8-2 composting reactor reached 50.12%after a degradation duration of 60 days.

  13. Twenty lectures on thermodynamics

    CERN Document Server

    Buchdahl, H A

    2013-01-01

    Twenty Lectures on Thermodynamics is a course of lectures, parts of which the author has given various times over the last few years. The book gives the readers a bird's eye view of phenomenological and statistical thermodynamics. The book covers many areas in thermodynamics such as states and transition; adiabatic isolation; irreversibility; the first, second, third and Zeroth laws of thermodynamics; entropy and entropy law; the idea of the application of thermodynamics; pseudo-states; the quantum-static al canonical and grand canonical ensembles; and semi-classical gaseous systems. The text

  14. Frequency of bacterial isolates and pattern of antimicrobial resistance in patients with hematological malignancies: A snapshot from tertiary cancer center

    Directory of Open Access Journals (Sweden)

    M Sengar

    2015-01-01

    Full Text Available BACKGROUND: Infections are the most important cause of mortality in patients with high-risk febrile neutropenia. Emergence of multi-drug resistant organisms (MDROs has become a major challenge for hemato-oncologists. Knowledge of the prevalent organisms and their antimicrobial sensitivity can help deciding the empirical therapy at individual centers and allows timely measures to reduce the risk of antimicrobial resistance. AIMS: To evaluate the frequency of bacterial isolates from all the samples and the pattern of bacterial bloodstream infections and incidence of MDROs. SETTINGS AND DESIGN: This is a retrospective analysis from a tertiary care cancer center. MATERIALS AND METHODS: From January to June 2014 information on all the samples received in Department of Microbiology was collected retrospectively. The data from samples collected from patients with hematological cancers were analyzed for types of bacterial isolates and antimicrobial sensitivity. RESULTS: A total of 739 isolates were identified with 67.9% of isolates being Gram-negative. The predominant Gram-negative organisms were Escherichia coli, Psuedomonas spp. and Klebsiella spp. Among the bacterial bloodstream infections, 66% were Gram-negative isolates. MDROs constituted 22% of all isolates in blood cultures. Incidence of resistant Gram-positive organisms was low in the present dataset (methicillin resistant Staphylococcus aureus and vancomycin-resistant enterococci-1.3%. CONCLUSIONS: The analysis reconfirms the Gram-negative organisms as the predominant pathogens in bacteremia seen in patients with hematological cancers. The high frequency of multi-drug resistance in the dataset calls for the need of emergency measures to curtail further development and propagation of resistant organisms.

  15. 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)

  16. 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.

  17. Textile Dye Removal from Wastewater Effluents Using Bioflocculants Produced by Indigenous Bacterial Isolates

    Directory of Open Access Journals (Sweden)

    Balakrishna Pillay

    2012-11-01

    Full Text Available Bioflocculant-producing bacteria were isolated from activated sludge of a wastewater treatment plant located in Durban, South Africa, and identified using standard biochemical tests as well as the analysis of their 16S rRNA gene sequences. The bioflocculants produced by these organisms were ethanol precipitated, purified using 2% (w/v cetylpyridinium chloride solution and evaluated for removal of wastewater dyes under different pH, temperature and nutritional conditions. Bioflocculants from these indigenous bacteria were very effective for decolourizing the different dyes tested in this study, with a removal rate of up to 97.04%. The decolourization efficiency was largely influenced by the type of dye, pH, temperature, and flocculant concentration. A pH of 7 was found to be optimum for the removal of both whale and mediblue dyes, while the optimum pH for fawn and mixed dye removal was found to be between 9 and 10. Optimum temperature for whale and mediblue dye removal was 35 °C, and that for fawn and mixed dye varied between 40–45 °C and 35–40 °C, respectively. These bacterial bioflocculants may provide an economical and cleaner alternative to replace or supplement present treatment processes for the removal of dyes from wastewater effluents, since they are biodegradable and easily sustainable.

  18. 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.

  19. 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

    2012-01-01

    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. PMID:22179248

  20. Bacterial Contamination and Antibiotic Resistance of Staphylococcus Aureus Isolated from Automated Teller Machine

    Directory of Open Access Journals (Sweden)

    Moshtaghi, H. (PhD

    2015-05-01

    Full Text Available Background and Objective: Automated Teller Machine (ATMs is likely to be contaminated with various microorganisms specially pathogen germs. This may be due to their exposure to dust and their vast dermal contact with multiple users. This study investigated the bacterial contamination on the keyboard of ATMs and drug resistance of the bacteria isolated from them. Material and Methods: the keyboards of 50 ATMs in Shahrekord city, Iran, were examined from October 2012 to February 2013. The sterile swab sticks moistened with Triptose soy broth were used for sampling. The bacteriological tests used were culture, biochemical test and agar disk diffusion method for antibiogram. Results: All the samples were found to be contaminated with Coagulase negative staphylococci (57.54%, Bacillus species (21.92%, Staphylococcus aureus (19.18% and coliform bacteria (1.36%. The resistance of Staphylococcus aureus was 92.8% to penicillin, 85.7% to amoxicilin، 71.4% to ampicillin, 57.1% to nytrofuran, 50% to tetracycline, 42.8% to erythromycin, 42.8% to gentamycin, 14.2 % to ciprofloxacin, 7.1% to trimethoprim and sulfamtuksazul. All species were susceptible to, ofloxacine, chloramphenicol, clindamycin, tobramycin, vancomycin and cefotaxime. Conclusion: given the presence of pathogens on ATMs and their role in transferring the contamination, we recommend considering personal hygiene and periodically disinfecting the keyboards to reduce contamination

  1. Textile dye removal from wastewater effluents using bioflocculants produced by indigenous bacterial isolates.

    Science.gov (United States)

    Buthelezi, Simphiwe P; Olaniran, Ademola O; Pillay, Balakrishna

    2012-11-30

    Bioflocculant-producing bacteria were isolated from activated sludge of a wastewater treatment plant located in Durban, South Africa, and identified using standard biochemical tests as well as the analysis of their 16S rRNA gene sequences. The bioflocculants produced by these organisms were ethanol precipitated, purified using 2% (w/v) cetylpyridinium chloride solution and evaluated for removal of wastewater dyes under different pH, temperature and nutritional conditions. Bioflocculants from these indigenous bacteria were very effective for decolourizing the different dyes tested in this study, with a removal rate of up to 97.04%. The decolourization efficiency was largely influenced by the type of dye, pH, temperature, and flocculant concentration. A pH of 7 was found to be optimum for the removal of both whale and mediblue dyes, while the optimum pH for fawn and mixed dye removal was found to be between 9 and 10. Optimum temperature for whale and mediblue dye removal was 35 °C, and that for fawn and mixed dye varied between 40–45 °C and 35–40 °C, respectively. These bacterial bioflocculants may provide an economical and cleaner alternative to replace or supplement present treatment processes for the removal of dyes from wastewater effluents, since they are biodegradable and easily sustainable.

  2. 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.

  3. 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.

  4. Antibacterial activity of carbapenems against clinical isolates of respiratory bacterial pathogens in the northeastern region of Japan in 2007.

    Science.gov (United States)

    Gomi, Kazunori; Fujimura, Shigeru; Fuse, Katsuhiro; Takane, Hidenari; Nakano, Yoshihisa; Kariya, Yasuko; Kikuchi, Toshiaki; Kurokawa, Iku; Tokue, Yutaka; Watanabe, Akira

    2011-04-01

    As the increasing prevalence of resistant strains of respiratory bacterial pathogens has recently been reported, continuous monitoring of the susceptibility of clinical isolates to antibacterial agents is important. We performed a surveillance study focusing on the susceptibility of major respiratory bacterial pathogens in the northeastern region of Japan to carbapenems and control drugs. A total of 168 bacterial strains isolated from patients with respiratory tract infections in 2007 were collected and the minimum inhibitory concentration (MIC) determined. MIC data were subjected to pharmacokinetic/pharmacodynamic analysis with Monte Carlo simulation to calculate the probability of achieving the target of time above MIC with each carbapenem. All Moraxella catarrhalis, Streptococcus pneumoniae, and methicillin-sensitive Staphylococcus aureus isolates were susceptible to carbapenems. Despite the increasing prevalence of β-lactamase-nonproducing ampicillin-resistant strains, all Haemophilus influenzae isolates were susceptible to meropenem. For Pseudomonas aeruginosa, the susceptibility rates for meropenem and biapenem were 76.7%, and the highest probability of achieving pharmacodynamic target (40% of the time above MIC) was obtained with meropenem 0.5 g three times daily as a 4-h infusion (89.4%), followed by meropenem 0.5 g four times daily as a 1-h infusion (88.4%). Carbapenems have retained their position as key drugs for severe respiratory tract infections.

  5. Persistent Staphylococcus aureus Isolates from Two Independent Cases of Bacteremia Display Increased Bacterial Fitness and Novel Immune Evasion Phenotypes

    Science.gov (United States)

    Richards, R. L.; Haigh, R. D.; Pascoe, B.; Sheppard, S. K.; Price, F.; Jenkins, D.; Rajakumar, K.

    2015-01-01

    Staphylococcus aureus bacteremia cases are complicated by bacterial persistence and treatment failure despite the confirmed in vitro susceptibility of the infecting strain to administered antibiotics. A high incidence of methicillin-resistant S. aureus (MRSA) bacteremia cases are classified as persistent and are associated with poorer patient outcomes. It is still unclear how S. aureus evades the host immune system and resists antibiotic treatment for the prolonged duration of a persistent infection. In this study, the genetic changes and associated phenotypic traits specific to S. aureus persistent bacteremia were identified by comparing temporally dispersed isolates from persistent infections (persistent isolates) originating from two independent persistent S. aureus bacteremia cases with the initial infection isolates and with three resolved S. aureus bacteremia isolates from the same genetic background. Several novel traits were associated specifically with both independent sets of persistent S. aureus isolates compared to both the initial isolates and the isolates from resolved infections (resolved isolates). These traits included (i) increased growth under nutrient-poor conditions; (ii) increased tolerance of iron toxicity; (iii) higher expression of cell surface proteins involved in immune evasion and stress responses; and (iv) attenuated virulence in a Galleria mellonella larva infection model that was not associated with small-colony variation or metabolic dormancy such as had been seen previously. Whole-genome sequence analysis identified different single nucleotide mutations within the mprF genes of all the isolates with the adaptive persistence traits from both independent cases. Overall, our data indicate a novel role for MprF function during development of S. aureus persistence by increasing bacterial fitness and immune evasion. PMID:26056388

  6. Persistent Staphylococcus aureus isolates from two independent cases of bacteremia display increased bacterial fitness and novel immune evasion phenotypes.

    Science.gov (United States)

    Richards, R L; Haigh, R D; Pascoe, B; Sheppard, S K; Price, F; Jenkins, D; Rajakumar, K; Morrissey, J A

    2015-08-01

    Staphylococcus aureus bacteremia cases are complicated by bacterial persistence and treatment failure despite the confirmed in vitro susceptibility of the infecting strain to administered antibiotics. A high incidence of methicillin-resistant S. aureus (MRSA) bacteremia cases are classified as persistent and are associated with poorer patient outcomes. It is still unclear how S. aureus evades the host immune system and resists antibiotic treatment for the prolonged duration of a persistent infection. In this study, the genetic changes and associated phenotypic traits specific to S. aureus persistent bacteremia were identified by comparing temporally dispersed isolates from persistent infections (persistent isolates) originating from two independent persistent S. aureus bacteremia cases with the initial infection isolates and with three resolved S. aureus bacteremia isolates from the same genetic background. Several novel traits were associated specifically with both independent sets of persistent S. aureus isolates compared to both the initial isolates and the isolates from resolved infections (resolved isolates). These traits included (i) increased growth under nutrient-poor conditions; (ii) increased tolerance of iron toxicity; (iii) higher expression of cell surface proteins involved in immune evasion and stress responses; and (iv) attenuated virulence in a Galleria mellonella larva infection model that was not associated with small-colony variation or metabolic dormancy such as had been seen previously. Whole-genome sequence analysis identified different single nucleotide mutations within the mprF genes of all the isolates with the adaptive persistence traits from both independent cases. Overall, our data indicate a novel role for MprF function during development of S. aureus persistence by increasing bacterial fitness and immune evasion.

  7. 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 CO2 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.

  8. Bacterial diversity in spent mushroom compost assessed by amplified rDNA restriction analysis and sequencing of cultivated isolates.

    Science.gov (United States)

    Ntougias, Spyridon; Zervakis, Georgios I; Kavroulakis, Nektarios; Ehaliotis, Constantinos; Papadopoulou, Kalliope K

    2004-11-01

    Spent mushroom compost (SMC) is the residual by-product of commercial Agaricus spp. cultivation, and it is mainly composed of a thermally treated cereal straw/animal manure mixture colonized by the fungal biomass. Research on the valorization of this material is mainly focusing on its use as soil conditioner and plant fertilizer. An investigation of the bacterial diversity in SMC was performed using molecular techniques in order to reveal the origin of SMC microflora and its potential effect on soil microbial communities after incorporation into agricultural soils. The bacterial population was estimated by the plate count method to a mean of 2.7 10(9) colony forming units (cfu) per g of dry weight, while the numbers of Gram-positive and Gram-negative bacteria were 1.9 10(9) and 4.9 10(8) cfu per g dw respectively as estimated by enumeration on semi-selective media. Fifty bacterial isolates were classified into 14 operational taxonomic units (OTUs) following ARDRA-PCR of the 16S rDNA gene. Sequencing of the 16S rDNA amplicon assigned 12 of the 14 OTUs to Gram-positive bacteria, associated with the genera Bacillus, Paenibacillus, Exiguobacterium, Staphylococcus, Desemzia, Carnobacterium, Brevibacterium, Arthrobacter and Microbacterium of the bacterial divisions Firmicutes and Actinobacteria. Two bacterial groups have phylogenetic links with the genera Comamonas and Sphingobacterium, which belong to beta-Proteobacteria and Bacteroidetes respectively. Two potentially novel bacteria are reported, which are associated with the genera Bacillus and Microbacterium. Most of the bacteria identified are of environmental origin, while strains related to species usually isolated from insects, animal and clinical sources were also detected. It appears that bacterial diversity in SMC is greatly affected by the origin of the initial material, its thermal pasteurization treatment and the potential unintended colonization of the mushroom substrate during the cultivation process.

  9. 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

    . Bacterial isolates from 794 Danish patients were tested and compared to 8,625 isolates from European patients. The minimal inhibitory concentrations of eight different antibiotics were determined using a microdilution plate. Similar to findings in European countries, the most common source of bacterial...... 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......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...

  10. Characterization of bacterial isolates from rubber dump site and their use in biodegradation of isoprene in batch and continuous bioreactors.

    Science.gov (United States)

    Srivastva, Navnita; Shukla, Awadhesh Kumar; Singh, Ram Sharan; Upadhyay, Siddh Nath; Dubey, Suresh Kumar

    2015-01-01

    Bacterial isolates from contaminated soil of a waste rubber dumping site were isolated and characterized using biochemical and molecular approaches. Isoprene degradation kinetics in batch mode (isoprene concentration: 100-1000 ppm) revealed the degradation efficiency of isolates as: Pseudomonas sp. (83%)>Alcaligenes sp. (70%)>Klebsiella sp. (68.5%). The most efficient isolate Pseudomonas sp. was finally inoculated in a specifically designed bioreactor system comprising a bioscrubber and a biofilter packed with polyurethane foam connected in series. The bioscrubber and biofilter units when operated in a series showed more than 90% removal efficiency up to the inlet loading rate (IL) of 371.1g/m(3)/h. Maximum elimination capacity (EC) of biofilter was found to be an order of magnitude greater than that for bioscrubber. Oxidative cleavage of the double bond of isoprene has been revealed through IR spectra of the leachate.

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

    Science.gov (United States)

    Shao, Ming-Wei; Lu, Yi-Hui; Miao, Shuang; Zhang, Yun; Chen, Ting-Ting; Zhang, Ying-Lao

    2015-01-01

    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.

  12. 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.

  13. 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

    2015-05-01

    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.

  14. Efficiency of silver nanoparticles against bacterial contaminants isolated from surface and ground water in Egypt

    Directory of Open Access Journals (Sweden)

    Reem Dosoky

    2015-06-01

    Full Text Available The bactericidal efficiency of silver nanoparticles (AgNP was evaluated against bacteria isolated from surface and ground water samples in Egypt. The AgNP were synthesized by typical one-step synthesis protocol, and were characterized using transmission electron microscopy and atomic absorption spectrophotometer. The bactericidal efficiency of AgNP was evaluated by its application in three concentrations i.e., 0.1, 0.05 and 0.01 ppm to water sample, and allowed to interact with bacteria for different duration e.g., 5 min 15 min, 30 min, 1 h and 2 h. Then, the bactericidal efficiency of AgNPs was determined by comparing the counted bacteria before and after the treatments. Higher mean values of total bacterial count (TBC, total coliform count (TCC, and total streptococcal count (TFS were detected in surface water than in ground water. Also, the results showed that TBC, TCC and TFS exceeded permissible limits. Application of AgNP at different concentration, the number of bacteria in TBC was significantly reduced in all AgNP-exposed samples as compared to the control group (p<0.05. The highest concentration of AgNP exhibited highest bactericidal efficiency in TBC, where, after two hours, 0.1, 0.05 and 0.01 mg/L AgNP was found to be sufficient to inhibit 91.85, 89.14 and 74.92%, and 92.33, 85.23 and 53.17% in TBC of surface and ground water, respectively. Moreover, the inhibition efficiency of the highest concentration (0.1 ppm against TCC reached to 98.10 and 99.88% in surface water and 95.54 and 99.20% in ground water after 1 h and 2 h, respectively. Similar results were found against TFS count. The AgNPs were found to be effective against bacteria of water origin.

  15. 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.

  16. 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.

  17. 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.

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

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    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.

  19. Isolation and characterization of different bacterial strains for bioremediation of n-alkanes and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Guermouche M'rassi, A; Bensalah, F; Gury, J; Duran, R

    2015-10-01

    Crude oil is a common environmental pollutant composed of a large number of both aromatic and aliphatic hydrocarbons. Biodegradation is carried out by microbial communities that are important in determining the fate of pollutants in the environment. The intrinsic biodegradability of the hydrocarbons and the distribution in the environment of competent degrading microorganisms are crucial information for the implementation of bioremediation processes. In the present study, the biodegradation capacities of various bacteria toward aliphatic and aromatic hydrocarbons were determined. The purpose of the study was to isolate and characterize hydrocarbon-degrading bacteria from contaminated soil of a refinery in Arzew, Algeria. A collection of 150 bacterial strains was obtained; the bacterial isolates were identified by 16S rRNA gene sequencing and their ability to degrade hydrocarbon compounds characterized. The isolated strains were mainly affiliated to the Gamma-Proteobacteria class. Among them, Pseudomonas spp. had the ability to metabolize high molecular weight hydrocarbon compounds such as pristane (C19) at 35.11 % by strain LGM22 and benzo[a] pyrene (C20) at 33.93 % by strain LGM11. Some strains were able to grow on all the hydrocarbons tested including octadecane, squalene, phenanthrene, and pyrene. Some strains were specialized degrading only few substrates. In contrast, the strain LGM2 designated as Pseudomonas sp. was found able to degrade both linear and branched alkanes as well as low and high poly-aromatic hydrocarbons (PAHs). The alkB gene involved in alkane degradation was detected in LGM2 and other Pseudomonas-related isolates. The capabilities of the isolated bacterial strains to degrade alkanes and PAHs should be of great practical significance in bioremediation of oil-contaminated environments.

  20. Characterization of bacterial isolates from the microbiota of mothers' breast milk and their infants.

    Science.gov (United States)

    Kozak, Kimberly; Charbonneau, Duane; Sanozky-Dawes, Rosemary; Klaenhammer, Todd

    2015-01-01

    This investigation assessed the potential of isolating novel probiotics from mothers and their infants. A subset of 21 isolates among 126 unique bacteria from breast milk and infant stools from 15 mother-infant pairs were examined for simulated GI transit survival, adherence to Caco-2 cells, bacteriocin production, and lack of antibiotic resistance. Of the 21 selected isolates a Lactobacillus crispatus isolate and 3 Lactobacillus gasseri isolates demonstrated good profiles of in vitro GI transit tolerance and Caco-2 cell adherence. Bacteriocin production was observed only by L. gasseri and Enterococcus faecalis isolates. Antibiotic resistance was widespread, although not universal, among isolates from infants. Highly similar isolates (≥ 97% similarity by barcode match) of Bifidobacterium longum subsp. infantis (1 match), Lactobacillus fermentum (2 matches), Lactobacillus gasseri (6 matches), and Enterococcus faecalis (1 match) were isolated from 5 infant-mother pairs. Antibiotic resistance profiles between these isolate matches were similar, except in one case where the L. gasseri isolate from the infant exhibited resistance to erythromycin and tetracycline, not observed in matching mother isolate. In a second case, L. gasseri isolates differed in resistance to ampicillin, chloramphenicol and vancomycin between the mother and infant. In this study, gram positive bacteria isolated from mothers' breast milk as well as their infants exhibited diversity in GI transit survival and acid inhibition of pathogens, but demonstrated limited ability to produce bacteriocins. Mothers and their infants offer the potential for identification of probiotics; however, even in the early stages of development, healthy infants contain isolates with antibiotic resistance.

  1. Feline cholecystitis and acute neutrophilic cholangitis: clinical findings, bacterial isolates and response to treatment in six cases.

    Science.gov (United States)

    Brain, Philip H; Barrs, Vanessa R; Martin, Patricia; Baral, Randolph; White, Joanna D; Beatty, Julia A

    2006-04-01

    Clinicopathological findings from six cats with confirmed cholecystitis or acute neutrophilic cholangitis are presented. Historical findings included lethargy and anorexia or inappetence of up to five days duration. On physical examination all cats were pyrexic and four out of six were jaundiced and had cranial abdominal pain. Bile samples were obtained by cholecystocentesis at exploratory coeliotomy (two cases) or by percutaneous, ultrasound-guided cholecystocentesis (four cases). Gall bladder rupture and bile peritonitis occurred subsequent to ultrasound-guided cholecystocentesis in one case. The most common bacterial isolate was Escherichia coli (four cases); E coli was isolated alone in two cases, in combination with a Streptococcus species (one case) and in combination with a Clostridium species (one case). Streptococcus species alone was isolated from one case, as was Salmonella enterica serovar Typhimurium. The latter is the first reported case of Salmonella-associated cholecystitis in a cat. Concurrent pancreatic or intestinal disease was detected histologically in three cases. All cases were treated with antimicrobials based on in vitro susceptibility results. Treatment was successful in five cases. One cat with concurrent diffuse epitheliotropic intestinal lymphoma was euthanased. Percutaneous ultrasound-guided cholecystocentesis is an effective, minimally-invasive technique enabling identification of bacterial isolates in cats with inflammatory hepatobiliary disease.

  2. Antibiotic Resistance Pattern Of Bacterial Pathogens Isolated From Poultry Manure Used To Fertilize Fish Ponds In New Bussa, Nigeria

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    Funso Omojowo

    2013-02-01

    Full Text Available This study was carried out to isolate and identify antibiotic resistant bacteria from poultry manure usually used for pond fertilization. Poultry manure from 120 Chickens in National Institute for Freshwater Fisheries Research (NIFFR integrated fish farms, New-Bussa, Nigeria was collected. Five bacterial pathogens; Salmonella typhi, Escherichia coli, Shigella dysenteriae, Staphylococcus aureus and Aeromonas hydrophila were isolated. Antibiotic susceptibility testing carried out using the disk diffusion technique. Antibiotics used were; ofloxacin, amoxicillin, tetracycline, ampicillin, erythromycin, gentamicin, nalidixic acid and chloramphenicol. All the isolated organisms were 100% sensitive to ofloxacin. The multiple resistance pattern revealed that 100% were resistant to tetracycline, 84.34% resistant to ampicillin, 76.68% resistant to amoxicillin, 66% resistant to chloramphenicol, 66% resistant to gentamicin, 29% resistant to erythromycin, 28.34% resistant to nalidixic acid. The risk posed by untreated poultry manure used in fish pond fertilization and the public health implications of these results were discussed.

  3. Isolation of bacterial plasmids by density gradient centrifugation in cesium trifluoroacetate (CsTFA) without the use of ethidium bromide.

    Science.gov (United States)

    Andersson, K; Hjorth, R

    1985-01-01

    Plasmids extracted from bacterial cells by alkaline extraction can easily be isolated from linear DNA by isopycnic centrifugation in CsTFA. This is a fast and simple method which circumvents the use of the intercalating dye, ethidium bromide, and consequently the problems associated with its removal. The buoyant densities for covalently closed circular DNA and linear DNA in CsTFA are 1.60 g/ml and 1.65 g/ml, respectively. The isolation is achieved regardless of plasmid size and can be accomplished at temperatures of between 4 and 30 degrees C. Plasmid DNA isolated in gradients of CsTFA are of a high purity and have been found to be intact when cleaved with restriction enzymes and ligated with T4 DNA ligase.

  4. Antimicrobial susceptibility pattern of bacterial isolates from wound infection and their sensitivity to antibiotic agents at super specialty hospital, Amravati city, India

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    Hrishikesh Sawdekar

    2015-02-01

    Full Text Available Background: Wound infection is one of the health problems that is caused and aggravated by the invasion of pathogenic organisms. Information on local pathogens and sensitivity to antimicrobial agent is crucial for successful treatment of wounds. So the present study was conducted to determine antimicrobial susceptibility pattern of bacterial isolates from wound infection and their sensitivity to antimicrobial agents. Methods: A retrospective study was conducted among patients with wound infection in Suyash super speciality hospital, from January 2012 to December 2013. Wound swab was collected using sterile cotton swabs and processed for bacterial isolation and susceptibility testing to Systemic antimicrobial agents. Results: In this study 78 bacterial isolates were recovered from 258 specimens showing an isolation rate of 31.2%. The predominant bacteria isolated from wounds were gram positive staphylococci 36 (46.2%, followed by gram negative streptococci 18 (23.1% gram negative pseudomonas 12 (15.4 % and gram negative proteus 8 (10.4%. The gram positive and gram negative bacteria constituted 68 (87.2% and 10 (12.8% of bacterial isolates; respectively. Conclusion: In the present study most of the pathogens isolated from wound isolates showed high rate of resistance to most commonly used newer antibiotics used to treat bacterial infections. Therefore, rational use of antibiotics should be practiced. [Int J Res Med Sci 2015; 3(2.000: 433-439

  5. Characterization of N-acyl homoserine lactones (AHLs) producing bacteria isolated from vacuum-packaged refrigerated turbot (Scophthalmus maximus) and possible influence of exogenous AHLs on bacterial phenotype.

    Science.gov (United States)

    Zhang, Caili; Zhu, Suqin; Jatt, Abdul-Nabi; Zeng, Mingyong

    2016-01-01

    Quorum sensing (QS) is a cell-to-cell communication mechanism through which microbial cells communicate and regulate their wide variety of biological activities. N-acyl homoserine lactones (AHLs) are considered to be the most important QS signaling molecules produced by several Gram-negative bacteria. The present study aimed to screen the AHLs-producing bacteria from spoiled vacuum-packaged refrigerated turbot (Scophthalmus maximus) by biosensor assays, and the profiles of AHLs produced by these bacteria were determined using reversed-phase thin-layer chromatography (RP-TLC) and gas chromatography-mass spectrometry (GC-MS). Effects of exogenous AHLs and QS inhibitor (QSI) on the phenotypes (i.e., extracellular proteolytic activity and biofilm formation) of the AHLs-producing bacteria were also evaluated. Our results demonstrated that eight out of twenty-two isolates were found to produce AHLs. Three of the AHLs-producing isolates were identified as Serratia sp., and the other five were found to belong to the family of Aeromonas. Two isolates (i.e., S. liquefaciens A2 and A. sobria B1) with higher AHLs-producing activities were selected for further studies. Mainly, RP-TLC and GC-MS analysis revealed three AHLs, i.e., 3-oxo-C6-HSL, C8-HSL and C10-HSL were produced by S. liquefaciens A2, while five AHLs, i.e., C4-HSL, C6-HSL, C8-HSL, C10-HSL, and C12-HSL, were produced by A. sobria B1. Moreover, production of AHLs in both bacterial strains were found to be density-dependent, and the AHLs activity reached a maximum level in their middle logarithmic phase and decreased in the stationary phase. The addition of exogenous AHLs and QSI decreased the specific protease activity both of the Serratia A2 and Aeromonas B1. Exogenous AHLs inhibited the biofilm formation of Serratia A2 while it enhanced the biofilm formation in Aeromonas B1. QSI inhibited the specific protease activity and biofilm formation in both bacterial strains.

  6. Two poplar-associated bacterial isolates induce additive favorable responses in a constructed plant-microbiome system

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    Collin M Timm

    2016-04-01

    Full Text Available The biological function of the plant-microbiome system is the result of contributions from the host plant and microbiome members. The Populus root microbiome is a diverse community that has high abundance of β- and γ-Proteobacteria, both classes which include multiple plant-growth promoting representatives. To understand the contribution of individual microbiome members in a community, we studied the function of a simplified community consisting of Pseudomonas and Burkholderia bacterial strains isolated from Populus hosts and inoculated on axenic Populus cutting in controlled laboratory conditions. Both strains increased lateral root formation and root hair production in Arabidopsis plate assays and are predicted to encode for different functions related to growth and plant growth promotion in Populus hosts. Inoculation individually, with either bacterial isolate, increased root growth relative to uninoculated controls, and while root area was increased in mixed inoculation, the interaction term was insignificant indicating additive effects of root phenotype. Complementary data including photosynthetic efficiency, whole-transcriptome gene expression and GC-MS metabolite expression data in individual and mixed inoculated treatments indicate that the effects of these bacterial strains are unique and additive. These results suggest that the function of a microbiome community may be predicted from the additive functions of the individual members.

  7. Exploring the Medicinal Potential of the Fruit Bodies of Oyster Mushroom, Pleurotus ostreatus (Agaricomycetes), against Multidrug-Resistant Bacterial Isolates.

    Science.gov (United States)

    Skariyachan, Sinosh; Prasanna, Apoorva; Manjunath, Sirisha P; Karanth, Soujanya S; Nazre, Ambika

    2016-01-01

    Bacterial resistance to present-generation antibiotics is increasing drastically, which has become a major public health concern. The present study focuses on demonstrating the antimicrobial potential of fruit bodies of the culinary/medicinal oyster mushroom Pleurotus ostreatus against clinical pathogens. Five bacterial isolates were collected from Sagar Hospital in Bangalore, India. The collected strains were grown on selective and differential media and antibiotic susceptibility testing was applied using 48 antibiotics by disc diffusion assay. The antibacterial efficiency of the mushroom extract against clinical pathogens, which were found to be multidrug resistant (MDR) to most of the tested antibiotics, was studied. The yield of cultivated mushrooms was evident at moist, cooler, and humid conditions. The clinical isolates of Staphylococcus aureus, Salmonella typhi, Acinetobacter sp., Proteus mirabilis, and Proteus spp. were found to be MDR to β-lactam, fluoroquinolones, sulfonamides, third- and fourth-generation cephalosporins, aminoglycosides, macrolides, tetracyclines, and carbapenems. The methanolic extracts of mushroom fruit bodies were found to be more effective than present-generation antibiotics against methicillin- and vancomycin- resistant S. aureus, S. typhi, Acinetobacter sp., and P. mirabilis at a concentration ranging from 50 to 100 µg/disc or 50 to 100 µL/well. The current study suggests that the methanolic extract of P. ostreatus can be used as a promising antibacterial agent against MDR bacterial pathogens.

  8. The Effect of Lactobacillus isolates on growth performance, immune response, intestinal bacterial community composition of growing Rex Rabbits.

    Science.gov (United States)

    Wang, C; Zhu, Y; Li, F; Huang, L

    2017-10-01

    The objective of this experiment was to investigate the effect of Lactobacillus isolates on intestinal bacterial community composition of growing Rex Rabbits. A total of 120 weaned Rex Rabbits (30 days old, 30 per group) were used for the experiment, which started after an adaptation period of 7 days. The control group was fed with basal diet only, while the treatment I, II and III groups were fed with basal diet adding antibiotics, Lactobacillus zeae (LB1) and Lactobacillus casei (L3) respectively. Growth performance, immune response and intestinal flora have been examined. The results obtained were as follows: (i) F/G of the rabbits fed with Lactobacillus isolates was significantly lower than that of the control group (p rabbits with Lactobacillus isolates. (iii) Lactobacillus isolates had no influence on the number of mast cells in duodenum and jejunum, but increased the number of mast cells in caecum significantly (p rabbit's intestinal flora can be changed by Lactobacillus isolates and antibiotics, especially for the microbial diversity and abundance in the caecum. In conclusion, the application of proper Lactobacillus isolates can improve the growth performance, enhance the immunological function and adjust the intestinal micro-ecosystem of growing Rex Rabbits. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

  9. A potent fish pathogenic bacterial killer Streptomyces sp. isolated from the soils of east coast region, South India

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    Durairaj Thirumurugan

    2013-10-01

    Full Text Available Objective: To investigate the potentiality of the marine actinobacteria isolated from marine soil against fish pathogenic bacteria. Methods: In the present study, a total of 33 soil samples were collected from the Bay of Bengal, east coast region (ECR of Tamilnadu, South India. Then they were used for the isolation of actinobacteria by using conventional serial dilution technique on starch casein agar medium. The antibacterial activities of the actinobacteria were screened primarily by using cross streak plate method against fish pathogenic bacteria namely Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio cholera, Aeromonas sp. and Pseudomonas sp. The antimicrobial efficacy of the selected isolates was carried out with various organic solvents, and finally the active compound was subjected to chromatographic techniques including TLC and GC-MS. Results: Of the 82 actinobacteria isolated, 21 (26% isolates were possessed antibacterial activity against fish pathogenic bacteria. Out of 21 antibacterial isolates, the isolate ECR77 was selected for further study based on its potential activity against fish pathogenic bacteria. Of the various solvents tested, the ethyl acetate extract had good antibacterial activity against the tested bacterial pathogens. The isolate ECR77 grew well on oat meal agar medium with 2% salt level at 35 °C. GC-MS study found that the presence of bioactive compounds namely tetradecanoic acid, n-hexadecanoic acid and octadecanoic acid. The morphological, physiological, biochemical and cultural characteristics of the potential isolate were supported the identity up to generic level as Streptomyces sp. ECR77. Conclusions: The results obtained from this study concludes that the ECR soils of South India is a hot spot of novel bioactive compound producing marine actinobacteria with great pharmaceutical values.

  10. A potent fish pathogenic bacterial killer Streptomyces sp. isolated from the soils of east coast region, South India

    Institute of Scientific and Technical Information of China (English)

    Durairaj Thirumurugan; Ramasamy Vijayakumar

    2013-01-01

    Objective: To investigate the potentiality of the marine actinobacteria isolated from marine soil against fish pathogenic bacteria.Methods:east coast region (ECR) of Tamilnadu, South India. Then they were used for the isolation of actinobacteria by using conventional serial dilution technique on starch casein agar medium. The antibacterial activities of the actinobacteria were screened primarily by using cross streak plate method against fish pathogenic bacteria namely Vibrio alginolyticus, Vibrio parahaemolyticus,Vibrio cholera, Aeromonas sp. and Pseudomonas sp. The antimicrobial efficacy of the selected isolates was carried out with various organic solvents, and finally the active compound was subjected to chromatographic techniques including TLC and GC-MS.Results:In the present study, a total of 33 soil samples were collected from the Bay of Bengal, against fish pathogenic bacteria. Out of 21 antibacterial isolates, the isolate ECR77 was selected for further study based on its potential activity against fish pathogenic bacteria. Of the various solvents tested, the ethyl acetate extract had good antibacterial activity against the tested bacterial pathogens. The isolate ECR77 grew well on oat meal agar medium with 2% salt level at 35 °C. GC-MS study found that the presence of bioactive compounds namely tetradecanoic acid,n-hexadecanoic acid and octadecanoic acid. The morphological, physiological, biochemical and cultural characteristics of the potential isolate were supported the identity up to generic level asStreptomyces sp. ECR77. Conclusions: The results obtained from this study concludes that the ECR soils of South India is a hot spot of novel bioactive compound producing marine actinobacteria with great pharmaceutical values. Of the 82 actinobacteria isolated, 21 (26%) isolates were possessed antibacterial activity.

  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. Characteristics of Bacterial Strains from Pseudomonas Genera Isolated from Diseased Plum Trees

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    Veljko Gavrilović

    2008-01-01

    Full Text Available Characteristics of Pseudomonas syringae strains isolated from diseased plum trees are presented is this paper. Based on pathogenic, biochemical and physiological characteristics, isolated starins were divided into two groups: First group of strains, isolated from diseased plum branches with symptoms of suden decay, was simillar to Pseudomonas syringae pv. syringae; second group of strains, isolated from necrotic flower buds on plum trees, exhibited characteristics simillar to Pseudomonas syringae pv. morsprunorum. In addition, phytopathogenic fungi belonging to genera Phomopsis, Botryosphaeria and Leucostoma, were also isolated from diseased plum trees. Further study of these pathogens and their role in the epidemiology of suden plum trees decay is in progress.

  13. Host Characteristics and Bacterial Traits Predict Experimental Virulence for Escherichia coli Bloodstream Isolates From Patients With Urosepsis.

    Science.gov (United States)

    Johnson, James R; Porter, Stephen; Johnston, Brian; Kuskowski, Michael A; Spurbeck, Rachel R; Mobley, Harry L T; Williamson, Deborah A

    2015-09-01

    Background.  Extraintestinal Escherichia coli infections are common, costly, and potentially serious. A better understanding of their pathogenesis is needed. Methods.  Sixty-seven E coli bloodstream isolates from adults with urosepsis (Seattle, WA; 1980s) underwent extensive molecular characterization and virulence assessment in 2 infection models (murine subcutaneous sepsis and moth larval lethality). Statistical comparisons were made among host characteristics, bacterial traits, and experimental virulence. Results.  The 67 source patients were diverse for age, sex, and underlying medical and urological conditions. The corresponding E coli isolates exhibited diverse phylogenetic backgrounds and virulence profiles. Despite the E coli isolates' common bloodstream origin, they exhibited a broad range of experimental virulence in mice and moth larvae, in patterns that (for the murine model only) corresponded significantly with host characteristics and bacterial traits. The most highly mouse-lethal strains were enriched with classic "urovirulence" traits and typically were from younger women with anatomically and functionally normal urinary tracts. The 2 animal models corresponded poorly with one another. Conclusions.  Host compromise, including older age and urinary tract abnormalities, allows comparatively low-virulence E coli strains to cause urosepsis. Multiple E coli traits predict both experimental and epidemiological virulence. The larval lethality model cannot be a substitute for the murine sepsis model.

  14. Kinetics of kill of bacterial conjunctivitis isolates with moxifloxacin, a fluoroquinolone, compared with the aminoglycosides tobramycin and gentamicin

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    Rudolph S Wagner

    2010-01-01

    Full Text Available Rudolph S Wagner1, David B Granet2, Steven J Lichtenstein3, Tiffany Jamison4, Joseph J Dajcs4, Robert D Gross5, Paul Cockrum41New Jersey Medical School, Newark, NJ, USA; 2Ratner Children’s Eye Center, University of California – San Diego, La Jolla, CA, USA; 3University of Illinois College of Medicine at Peoria, Peoria, Illinois, USA; 4Alcon Research, Ltd, Fort Worth, TX, USA; 5Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX, USAPurpose: To compare the kinetics and speed of kill of Streptococcus pneumoniae and Haemophilus influenzae on exposure to three topical ophthalmic antibiotic solutions.Materials and methods: Bacterial conjunctivitis isolates of S. pneumoniae and H. influenzae were exposed to 1:1000 dilutions of moxifloxacin 0.5%, tobramycin 0.3%, gentamicin 0.3%, and water (control. At 15, 30, 60, 120, and 180 minutes after exposure, aliquots were collected, cells were cultured, and viable cell counts were determined using standard microbiological methods.Results: Moxifloxacin achieved 99.9% kill (3-log reduction at approximately 2 hours for S. pneumoniae and at 15 minutes for H. influenzae. Tobramycin and gentamicin did not achieve 3-log reduction of S. pneumoniae during the 180-minute study period. An increase in bacterial growth was noted for these isolates. Gentamicin took more than 120 minutes to achieve the 3-log reduction of H. influenzae and tobramycin did not reach the 3-log reduction of this pathogen during the 180-minute study period.Conclusion: Moxifloxacin killed S. pneumoniae and H. influenzae in vitro faster than tobramycin and gentamicin, suggesting its potential clinical benefit as a first-line treatment for bacterial conjunctivitis to minimize patient symptoms and to limit the contagiousness of the disease.Keywords: kinetics of kill, bacterial conjunctivitis, in vitro, Streptococcus pneumoniae, Haemophilus influenzae, fluoroquinolones, aminoglycosides

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

    Science.gov (United States)

    Hendriksen, Rene S; Mevius, Dik J; Schroeter, Andreas; Teale, Christopher; Meunier, Danièle; Butaye, Patrick; Franco, Alessia; Utinane, Andra; Amado, Alice; Moreno, Miguel; Greko, Christina; Stärk, Katharina; Berghold, Christian; Myllyniemi, Anna-Liisa; Wasyl, Dariusz; Sunde, Marianne; Aarestrup, Frank M

    2008-07-08

    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. 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. 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 tetracycline, gentamicin and erythromycin. More resistance

  16. 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

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

    Science.gov (United States)

    Hendriksen, Rene S; Mevius, Dik J; Schroeter, Andreas; Teale, Christopher; Meunier, Danièle; Butaye, Patrick; Franco, Alessia; Utinane, Andra; Amado, Alice; Moreno, Miguel; Greko, Christina; Stärk, Katharina; Berghold, Christian; Myllyniemi, Anna-Liisa; Wasyl, Dariusz; Sunde, Marianne; Aarestrup, Frank M

    2008-01-01

    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 tetracycline

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

    Science.gov (United States)

    Mathur, Ankita; Kumari, Jyoti; Parashar, Abhinav; T., Lavanya; Chandrasekaran, N.; Mukherjee, Amitava

    2015-01-01

    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. PMID:26496250

  19. Removal of 2,4,5-trichlorophenol by bacterial isolates from the secondary sludge of pulp and paper mill.

    Science.gov (United States)

    Karn, Santosh Kr; Reddy, M Sudhakara

    2013-09-01

    2,4,5-trichlorophenol (2,4,5-TCP) mineralizing bacteria were isolated from the secondary sludge of pulp and paper industry. These isolates used 2,4,5-TCP as a source of carbon and energy and were capable of degrading this compound, as indicated by stoichimetric release of chloride and biomass formation. Based on 16S rRNA sequence analysis, these bacteria were identified as Kocuria sp. (CL2), Bacillus pumillus (CL5), Pseudomonas stutzeri (CL7). HPLC analysis revealed that these isolates were able to degrade 2,4,5-TCP at higher concentrations (600 mg/l or 3.0 mM). A consortia of these isolates completely removed 2,4,5-TCP from the sludge obtained from pulp and paper mill within 2 weeks when supplemented at a rate of 100 mg l(-1) . Bacterial consortium also significantly reduced absorbable organic halogen (AOX) and extractable organic halogen (EOX) by 61% and 63%, respectively from the sludge. These isolates have high potential to remove 2,4,5-TCP and may be used for remediation of pulp paper mill waste containing 2,4,5-TCP.

  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.

  1. 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.

  2. Usefulness of the MicroSeq 500 16S rDNA bacterial identification system for identification of anaerobic Gram positive bacilli isolated from blood cultures

    OpenAIRE

    Chan, Km; Yuen, KY; Que, TI; Woo, GKS; Fung, Amy; Yip, KT; Woo, PCY; Ng, KHL; Lau, SKP

    2006-01-01

    Using full 16S ribosomal RNA (rRNA) gene sequencing as the gold standard, 20 non-duplicating anaerobic Gram positive bacilli isolated from blood cultures were analysed by the MicroSeq 500 16S rDNA bacterial identification system. The MicroSeq system successfully identified 13 of the 20 isolates. Four and three isolates were misidentified at the genus and species level, respectively. Although the MicroSeq 500 16S rDNA bacterial identification system is better than three commercially available ...

  3. Usefulness of the MicroSeq 500 16S rDNA bacterial identification system for identification of anaerobic Gram positive bacilli isolated from blood cultures

    OpenAIRE

    Lau, S.K.P.; Ng, K H L; Woo, P C Y; Yip, K‐t; Fung, A M Y; Woo, G K S; Chan, K‐m; Que, T‐L

    2006-01-01

    Using full 16S ribosomal RNA (rRNA) gene sequencing as the gold standard, 20 non‐duplicating anaerobic Gram positive bacilli isolated from blood cultures were analysed by the MicroSeq 500 16S rDNA bacterial identification system. The MicroSeq system successfully identified 13 of the 20 isolates. Four and three isolates were misidentified at the genus and species level, respectively. Although the MicroSeq 500 16S rDNA bacterial identification system is better than three commercially available ...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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. PMID:27774456

  6. Antibacterial activity of norfloxacin against bacterial isolates from the urinary tract.

    Science.gov (United States)

    Qadri, S. M.; Johnson, S.

    1989-01-01

    Two hundred fourteen isolates from clinical specimens were tested in vitro to determine their susceptibility pattern against norfloxacin. Of the 151 strains of gram-negative bacteria tested, 149 (98.7%) were susceptible. Sixty-three (100%) of the gram-positive bacteria tested were also susceptible to norfloxacin. Norfloxacin showed excellent activity against all bacteria isolated from urine. PMID:2738947

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Biological decolorization of the reactive dyes Reactive Black 5 by a novel isolated bacterial strain Enterobacter sp. EC3.

    Science.gov (United States)

    Wang, Hui; Zheng, Xiao-Wei; Su, Jian-Qiang; Tian, Yun; Xiong, Xiao-Jing; Zheng, Tian-Ling

    2009-11-15

    Studies were carried out on the decolorization of the reactive dye Reactive Black 5 by a newly isolated bacterium, EC3. Phenotypic characterization and phylogenetic analysis based on 16S rDNA sequence comparisons indicate that this strain belonged to the genus Enterobacter. The optimal conditions for the decolorizing activity of Enterobacter sp. EC3 were anaerobic conditions with glucose supplementation, at pH 7.0, and 37 degrees C. The maximum decolorization efficiency against Reactive Black 5 achieved in this study was 92.56%. Ultra-violet and visible (UV-vis) analyses before and after decolorization and the colorless bacterial biomass after decolorization suggested that decolorization was due to biodegradation, rather than inactive surface adsorption. The bacterial strain also showed a strong ability to decolorize various reactive textile dyes, including both azo and anthraquinone dyes. To our knowledge, it is the first time that a bacterial strain of Enterobacter sp. has been reported with decolorizing ability against both azo and anthraquinone dyes.

  9. INVESTIGATION OF ANTIMICROBIAL ACTIVITY COMBINED PREPARATIONS FOR CLINICAL STRAINS OF MICROORGANISMS ISOLATED FROM PATIENTS WITH BACTERIAL VAGINIT

    Directory of Open Access Journals (Sweden)

    Aslanian M. A.

    2015-12-01

    Full Text Available The problem of bacterial vaginit in some cases the cause of severe infectious diseases genitalia of the fetus and newborn, which can impair the health of future generations. It is noted that the treatment of antibacterial agents observed numerous negative side effects- reducing the biochemical activity of the intestinal microflora, abuse microbiota, leading to the development of dysbiosis, increasing the number of resistant strains of pathogens, the risk of allergic reaction sand immunological disorders. A study was conducted towards finding effective combinations of drugs from different pharmacological groups means to create a combination of drugs. The aim of the study was to develop and explore and Flamini combination of miramistin combined medicines to treat bacterial vaginit. As a result of studies in patients with bacterial vaginit pathological material was isolated and identified 72 strains of microorganisms (Staphylococcus spp, Streptococcus spp, Enterococcus spp, Escherichia coli, Haemophillu sssp, Candida albican sand various strains of anaerobic microorganisms. For the combined treatment of infectious and in flammatory diseases (mixed infections in humans the combined drugin tablet form. All clinical strains of microorganisms isolated from patients with bacterial vaginit were tested for sensitivity to the combined preparation in tablet form with Flamini and miramistin. The greatest sensitivity to the drugs found clinical strains of microorganisms: Staphylococcu saureus, Staphylococcus epidermidis, Peptococcus niger (diameter zone growth retardation is 25,5-23,5 mm. composition tablets number 1 (0.05 g Flamini, miramistini 0.02 g, which was selected for further study shows bacteriostatic effect against a wide range of microorganisms and fungi Rod Candida. IPC for Staphylococcus sp was 20-25 pg / mL for Streptococcus sp 35,0-40,0 mg / ml, for intestinal group 35,0-40,0 for fungi 30,0 mg / ml unlike pills number 2 and number 3, where the

  10. Activity of Norspermidine on Bacterial Biofilms of Multidrug-Resistant Clinical Isolates Associated with Persistent Extremity Wound Infections.

    Science.gov (United States)

    Cardile, Anthony P; Woodbury, Ronald L; Sanchez, Carlos J; Becerra, Sandra C; Garcia, Rebecca A; Mende, Katrin; Wenke, Joseph C; Akers, Kevin S

    2016-11-19

    Biofilm formation is a major virulence factor for numerous pathogenic bacteria and is cited as a central event in the pathogenesis of chronic human infections, which is in large part due to excessive extracellular matrix secretion and metabolic changes that occur within the biofilm rendering them highly tolerant to antimicrobial treatments. Polyamines, including norspermidine, play central roles in bacterial biofilm development, but have also recently been shown to inhibit biofilm formation in select strains of various pathogenic bacteria. The aim of this study was to evaluate in vitro the biofilm dispersive and inhibitory activities of norspermidine against multidrug-resistant clinical isolates of Acinetobacter baumannii(n = 4), Klebsiella pneumoniae (n = 3), Pseudomonas aeruginosa (n = 5) and Staphylococcus aureus (n = 4) associated with chronic extremity wound infections using the semi-quantitative 96-well plate method and confocal laser microscopy. In addition to the antibiofilm activity, biocompatibility of norspermidine was also evaluated by measuring toxicity in vitro to human cell lines and whole porcine tissue explants using MTT viability assay and histological analysis. Norspermidine (5-20 mM) had variable dispersive and inhibitory activity on biofilms which was dependent on both the strain and species. Of the clinical bacterial species evaluated herein, A. baumannii isolates were the most sensitive to the effect of norspermidine, which was in part due to the inhibitory effects of norspermidine on bacterial motility and expression of genes involved in the production of homoserine lactones and quorum sensing molecules both essential for biofilm formation. Importantly, exposure of cell lines and whole tissues to norspermidine for prolonged periods of time (≥24 h) was observed to reduce viability and alter tissue histology in a time and concentration dependent manner, with 20 mM exposure having the greatest negative effects on both

  11. 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.

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

    Science.gov (United States)

    da Costa, Pedro Beschoren; Granada, Camille E; Ambrosini, Adriana; Moreira, Fernanda; de Souza, Rocheli; dos Passos, João Frederico M; Arruda, Letícia; Passaglia, Luciane M P

    2014-01-01

    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.

  13. Prevalence and Bacterial Isolates of Mastitis in Dairy Farms in Selected Districts of Eastern Harrarghe Zone, Eastern Ethiopia.

    Science.gov (United States)

    Zeryehun, Tesfaheywet; Abera, Gerema

    2017-01-01

    The study was conducted from November 2015 to April 2016 to estimate the prevalence of clinical and subclinical mastitis in lactating cows, to assess the associated risk factors, and to isolate the major bacterial pathogens in dairy farms in selected district of Eastern Harrarghe Zone, Eastern Ethiopia. The study was carried out in 384 dairy cows based on data collection, farm visit, animal examination, California mastitis test (CMT), and isolation bacterial pathogens using standard techniques. In the present study the overall mastitis at cow level was 247 (64.3%). The prevalence of clinical and subclinical mastitis and quarter level prevalence for clinical and subclinical mastitis were 12.5% and 51.8% at cow level and 10.7% and 46.4% at quarter level, respectively. Clinically, 101 (6.6%) quarters which belong to 75 (19.5%) animals were found to be with blind teat. In the present study prevalence of mastitis was significantly associated with parity and age (p mastitis particularly the subclinical mastitis was major problem of dairy cows in the area and hence warrants serious attention.

  14. The uptake of Ni2+ and Ag+ by bacterial strains isolated from a boreal nutrient-poor bog

    Directory of Open Access Journals (Sweden)

    Merja Lusa

    2016-05-01

    Full Text Available We studied the uptake of Ni2+ and Ag+ by bacterial strains of Paenibacillus, Pseudomonas, Burkholderia and Rhodococcus isolated from an acidic nutrient-poor boreal bog. The tests were run in two different growth media at two temperatures; +4 °C and +20 °C. All bacterial strains removed Ni2+ and Ag+ from the solution with highest efficiencies shown by one of the Pseudomonas sp. and one of the Paenibacillus sp. strains. Highest Ni2+ uptake was found in 1% Tryptone solution, whereas the highest removal of Ag+ was obtained using 1% Yeast extract. Temperature affected the uptake of Ni2+ and Ag+, but statistically significant difference was found only for Ni2+. Based on tests carried out for the bacteria in nutrient broths and for fresh samples taken from varying depth up to seven meters from the ombrotrophic bog, from which the bacteria were isolated, we estimated that in in situ conditions of the bog the uptake of Ni2+ by bacteria accounts for approximately 0.02% of the total sorption in the uppermost moss layer, 0.01% in the peat layer, 0.02% in the gyttja layer and 0.1% in the bottom clay layer of the bog. For Ag+ the corresponding values were 2.3% in the moss layer, 0.04% in the peat layer, 0.2% in the gyttja and 0.03% in the clay layer.

  15. Diversity and antimicrobial potential of bacterial isolates associated with the soft coral Alcyonium digitatum from the Baltic Sea.

    Science.gov (United States)

    Pham, Thi Mien; Wiese, Jutta; Wenzel-Storjohann, Arlette; Imhoff, Johannes F

    2016-01-01

    It is well recognized that microorganisms associated with marine invertebrates, in particular sponges and hard corals, are an excellent source of new natural products. Therefore, the diversity of bacteria associated with marine invertebrates and their potential to produce bioactive compounds have received much attention in recent years. We report here for the first time on the biodiversity of bacteria associated with the soft coral Alcyonium digitatum, which is abundant in the Baltic Sea. In order to increase the cultured diversity, bacteria were isolated using four different media, identified with support of 16S rRNA gene sequences and screened for antimicrobial activity using two different media. Activity of crude extracts was tested against Bacillus subtilis, Staphylococcus epidermidis, Escherichia coli, and the yeast Candida albicans. A total of 251 coral-associated bacterial isolates were classified and found to belong to 41 species in 14 genera of the Firmicutes, Actinobacteria, Gammaproteobacteria, and Alphaproteobacteria. The genus Bacillus was most abundant and diverse with 17 recognized species. Forty-eight percent of all 251 isolates exhibited antimicrobial activity. All isolates of Bacillus methylotrophicus and Bacillus amyloliquefaciens displayed inhibition of at least three out of the four tested microorganisms. It became obvious during this study that the production of antibiotic substances not only is strain-specific, but in many cases also depends on the media composition and growth conditions. In addition, the antimicrobial potential of bacteria associated with A. digitatum may represent a promising source for antimicrobial substances.

  16. 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.

  17. 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.

  18. Evaluating robustness of a diesel-degrading bacterial consortium isolated from contaminated soil

    DEFF Research Database (Denmark)

    Sydow, Mateusz; Owsianiak, Mikolaj; Szczepaniak, Zuzanna;

    2016-01-01

    It is not known whether diesel-degrading bacterial communities are structurally and functionally robust when exposed to different hydrocarbon types. Here, we exposed a diesel-degrading consortium to model either alkanes, cycloalkanes or aromatic hydrocarbons as carbon sources to study its...... structural resistance. The structural resistance was low, with changes in relative abundances of up to four orders of magnitude, depending on hydrocarbon type and bacterial taxon. This low resistance is explained by the presence of hydrocarbon-degrading specialists in the consortium and differences in growth...... kinetics on individual hydrocarbons. However, despite this low resistance, structural and functional resilience were high, as verified by re-exposing the hydrocarbon-perturbed consortium to diesel fuel. The high resilience is either due to the short exposure time, insufficient for permanent changes...

  19. Characterization of Bacterial Strains Isolated Through Microbial Profiling of Urine Samples

    Directory of Open Access Journals (Sweden)

    Poulomi Nandy

    2007-01-01

    Full Text Available The present study was conducted to determine the microbial profile in urine samples. Differential and selective chromogenic culture media were used for the rapid detection, identification and enumeration of urinary tract pathogens namely, E. coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, Proteus mirabilis. Urine samples of normal healthy individuals as well as patients with Urinary Tract Infection (UTI were screened on hicrome agar plates. The cultivable bacteria present in urine were isolated based on chromogenic detection. Antibiotic sensitivity assay, morphological characterization and biochemical tests, namely protease, oxidase, catalase, lipase, DNase and lecithinase assay were performed with the 15 isolates obtained from urine samples. The molecular analyses of the isolates were done through partial sequencing of the 16SrDNA gene; six of them were found to be novel and submitted in GenBank under the accession numbers EF644491-96. Phylogenetic tree of the isolates were constructed by neighbour joining method.

  20. Prevalence and antibiogram of bacterial isolates from urinary tract infections at Dessie Health Research Laboratory, Ethiopia

    Directory of Open Access Journals (Sweden)

    Mulugeta Kibret

    2014-02-01

    Conclusions: In the study area resistance rates to erythromycin, amoxycillin and tetracycline were high. Since most isolates were sensitive to nitrofurantoin and gentamicin, they are considered as appropriate antimicrobials for empirical treatment urinary tract infections.

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

    OpenAIRE

    Carmen Dragomir; Rodica Schipor; Neculai Dragomir; Nicoleta Moraru; Claudiu Ghiocel; Darius Văcariu

    2013-01-01

    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 is...

  2. 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.

  3. 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

  4. Selected lactic acid-producing bacterial isolates with the capacity to reduce Salmonella translocation and virulence gene expression in chickens.

    Science.gov (United States)

    Yang, Xiaojian; Brisbin, Jennifer; Yu, Hai; Wang, Qi; Yin, Fugui; Zhang, Yonggang; Sabour, Parviz; Sharif, Shayan; Gong, Joshua

    2014-01-01

    Probiotics have been used to control Salmonella colonization/infection in chickens. Yet the mechanisms of probiotic effects are not fully understood. This study has characterized our previously-selected lactic acid-producing bacterial (LAB) isolates for controlling Salmonella infection in chickens, particularly the mechanism underlying the control. In vitro studies were conducted to characterize 14 LAB isolates for their tolerance to low pH (2.0) and high bile salt (0.3-1.5%) and susceptibility to antibiotics. Three chicken infection trials were subsequently carried out to evaluate four of the isolates for reducing the burden of Salmonella enterica serovar Typhimurium in the broiler cecum. Chicks were gavaged with LAB cultures (10(6-7) CFU/chick) or phosphate-buffered saline (PBS) at 1 day of age followed by Salmonella challenge (10(4) CFU/chick) next day. Samples of cecal digesta, spleen, and liver were examined for Salmonella counts on days 1, 3, or 4 post-challenge. Salmonella in the cecum from Trial 3 was also assessed for the expression of ten virulence genes located in its pathogenicity island-1 (SPI-1). These genes play a role in Salmonella intestinal invasion. Tested LAB isolates (individuals or mixed cultures) were unable to lower Salmonella burden in the chicken cecum, but able to attenuate Salmonella infection in the spleen and liver. The LAB treatments also reduced almost all SPI-1 virulence gene expression (9 out of 10) in the chicken cecum, particularly at the low dose. In vitro treatment with the extracellular culture fluid from a LAB culture also down-regulated most SPI-1 virulence gene expression. The possible correlation between attenuation of Salmonella infection in the chicken spleen and liver and reduction of Salmonella SPI-1 virulence gene expression in the chicken cecum by LAB isolates is a new observation. Suppression of Salmonella virulence gene expression in vivo can be one of the strategies for controlling Salmonella infection in chickens.

  5. Measuring the CCN and IN ability of bacterial isolates: implications for the southeastern United States and Puerto Rico

    Science.gov (United States)

    Purdue, S.; Waters, S.; Konstantinidis, K.; Nenes, A.; DeLeon-Rodriguez, N.

    2015-12-01

    Ice nucleation is an important process in the climate system as it influences global precipitation processes, and can affect the vertical distribution of clouds with effects that both cool and warm the atmosphere. Of the pathways to ice nucleation, immersion mode, which occurs when ice nuclei (IN) particles are surrounded by an aqueous phase that subsequently freezes, dominates primary ice production in mixed-phase clouds. A simple but effective method to study immersion freezing is to utilize a droplet freezing assay (DFA) that consists of an aluminum plate, precisely cooled by a continuous flow of an ethylene glycol-water mixture. Using such a system we study the immersion IN characteristics of bacterial isolates (for temperatures ranging from -15oC to 0oC) isolated from rainwater and air collected in Atlanta, GA and Puerto Rico, over storms throughout the year. Despite their relatively large size and the presence of hydrophilic groups on the outer membranes of many bacteria, it is unclear if bacteria possess an inherent ability to nucleate an aqueous phase (a requirement for immersion freezing) for the wide range of supersaturations found in clouds. For this, we measure the cloud condensation nucleation (CCN) activity of each isolate (over the 0.05% to 0.6% supersaturation range) using a Continuous Flow Streamwise Thermal Gradient CCN Counter. Initial results have shown certain isolates to be very efficient CCN, allowing them to form droplets even for the very low supersaturations found in radiation fogs. In combination, these experiments provide insight into the potential dual-ability of some bacteria, isolated from the southeastern United States and Puerto Rico, to act as both efficient CCN and IN.

  6. Mechanisms, molecular and sero-epidemiology of antimicrobial resistance in bacterial respiratory pathogens isolated from Japanese children

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    Sunakawa Keisuke

    2007-08-01

    Full Text Available Abstract Background The clinical management of community-acquired respiratory tract infections (RTIs is complicated by the increasing worldwide prevalence of antibacterial resistance, in particular, β-lactam and macrolide resistance, among the most common causative bacterial pathogens. This study aimed to determine the mechanisms and molecular- and sero-epidemiology of antibacterial resistance among the key paediatric respiratory pathogens in Japan. Methods Isolates were collected at 18 centres in Japan during 2002 and 2003 from children with RTIs as part of the PROTEKT surveillance programme. A proportion of Haemophilus influenzae isolates was subjected to sequencing analysis of the ftsI gene; phylogenetic relatedness was assessed using multilocus sequence typing. Streptococcus pneumoniae isolates were screened for macrolide-resistance genotype by polymerase chain reaction and serotyped using the capsular swelling method. Susceptibility of isolates to selected antibacterials was performed using CLSI methodology. Results and Discussion Of the 557 H. influenzae isolates collected, 30 (5.4% were β-lactamase-positive [BL+], 115 (20.6% were BL-nonproducing ampicillin-resistant (BLNAR; MIC ≥ 4 mg/L and 79 (14.2% were BL-nonproducing ampicillin-intermediate (BLNAI; MIC 2 mg/L. Dabernat Group III penicillin binding protein 3 (PBP3 amino acid substitutions in the ftsI gene were closely correlated with BLNAR status but phylogenetic analysis indicated marked clonal diversity. PBP mutations were also found among BL+ and BL-nonproducing ampicillin-sensitive isolates. Of the antibacterials tested, azithromycin and telithromycin were the most active against H. influenzae (100% and 99.3% susceptibility, respectively. A large proportion (75.2% of the 468 S. pneumoniae isolates exhibited macrolide resistance (erythromycin MIC ≥ 1 mg/L; erm(B was the most common macrolide resistance genotype (58.8%, followed by mef(A (37.2%. The most common pneumococcal

  7. Radiation Induced DNA Double Strand Break Studies of a Metal Sensitive Novel Bacterial Isolate from East Calcutta Wetland

    Directory of Open Access Journals (Sweden)

    Sanhita Chowdhury

    2009-01-01

    uncultivable anaerobic bacterial isolate and predict the growth conditions for the isolate. On irradiation with 60Co γ rays the isolate showed maximum repair following 60 Gray damage. DNA polymerase inhibitor arabinose CTP inhibited the repair mechanism completely. This indicated that DNA polymerase took active part in repair process and thus the mechanism was that of homologous recombination repair.

  8. Microbial enhanced heavy crude oil recovery through biodegradation using bacterial isolates from an Omani oil field.

    Science.gov (United States)

    Al-Sayegh, Abdullah; Al-Wahaibi, Yahya; Al-Bahry, Saif; Elshafie, Abdulkadir; Al-Bemani, Ali; Joshi, Sanket

    2015-09-16

    Biodegradation is a cheap and environmentally friendly process that could breakdown and utilizes heavy crude oil (HCO) resources. Numerous bacteria are able to grow using hydrocarbons as a carbon source; however, bacteria that are able to grow using HCO hydrocarbons are limited. In this study, HCO degrading bacteria were isolated from an Omani heavy crude oil field. They were then identified and assessed for their biodegradation and biotransformation abilities under aerobic and anaerobic conditions. Bacteria were grown in five different minimum salts media. The isolates were identified by MALDI biotyper and 16S rRNA sequencing. The nucleotide sequences were submitted to GenBank (NCBI) database. The bacteria were identified as Bacillus subtilis and B. licheniformis. To assess microbial growth and biodegradation of HCO by well-assay on agar plates, samples were collected at different intervals. The HCO biodegradation and biotransformation were determined using GC-FID, which showed direct correlation of microbial growth with an increased biotransformation of light hydrocarbons (C12 and C14). Among the isolates, B. licheniformis AS5 was the most efficient isolate in biodegradation and biotransformation of the HCO. Therefore, isolate AS5 was used for heavy crude oil recovery experiments, in core flooding experiments using Berea core plugs, where an additional 16 % of oil initially in place was recovered. This is the first report from Oman for bacteria isolated from an oil field that were able to degrade and transform HCO to lighter components, illustrating the potential use in HCO recovery. The data suggested that biodegradation and biotransformation processes may lead to additional oil recovery from heavy oil fields, if bacteria are grown in suitable medium under optimum growth conditions.

  9. 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...... 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...

  10. Pure bacterial isolates that convert p-xylene to terephthalic acid.

    Science.gov (United States)

    Bramucci, M G; McCutchen, C M; Singh, M; Thomas, S M; Larsen, B S; Buckholz, J; Nagarajan, V

    2002-02-01

    Bacteria that grow on p-xylene, p-toluic acid, and terephthalic acid (TPA) were isolated from a wastewater bioreactor that is used to treat a waste stream that contains all three of these compounds. Although previously described aerobic bacteria degrade p-xylene by initially oxidizing a single methyl group to form p-toluic acid and then cleaving the aromatic ring, some of the bacteria isolated during this study transformed p-xylene by oxidizing both methyl groups to produce TPA.

  11. Tessaracoccus massiliensis sp. nov., a new bacterial species isolated from the human gut

    Directory of Open Access Journals (Sweden)

    E. Seck

    2016-09-01

    Full Text Available A new Actinobacterium, designated Tessaracoccus massiliensis type strain SIT-7T (= CSUR P1301 = DSM 29060, have been isolated from a Nigerian child with kwashiorkor. It is a facultative aerobic, Gram positive, rod shaped, non spore-forming, and non motile bacterium. Here, we describe the genomic and phenotypic characteristics of this isolate. Its 3,212,234 bp long genome (1 chromosome, no plasmid exhibits a G+C content of 67.81% and contains 3,058 protein-coding genes and 49 RNA genes.

  12. 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.

  13. 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.

  14. 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

    2013-01-01

    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. PMID:23924881

  15. 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.

  16. Effect of metals on a siderophore producing bacterial isolate and its implications on microbial assisted bioremediation of metal contaminated soils.

    Science.gov (United States)

    Gaonkar, Teja; Bhosle, Saroj

    2013-11-01

    A bacterial isolate producing siderophore under iron limiting conditions, was isolated from mangroves of Goa. Based on morphological, biochemical, chemotaxonomical and 16S rDNA studies, the isolate was identified as Bacillus amyloliquefaciens NAR38.1. Preliminary characterization of the siderophore indicated it to be catecholate type with dihydroxy benzoate as the core component. Optimum siderophore production was observed at pH 7 in mineral salts medium (MSM) without any added iron with glucose as the carbon source. Addition of NaCl in the growth medium showed considerable decrease in siderophore production above 2% NaCl. Fe(+2) and Fe(+3) below 2 μM and 40 μM concentrations respectively, induced siderophore production, above which the production was repressed. Binding studies of the siderophore with Fe(+2) and Fe(+3) indicated its high affinity towards Fe(+3). The siderophore concentration in the extracellular medium was enhanced when MSM was amended with essential metals Zn, Co, Mo and Mn, however, decreased with Cu, while the concentration was reduced with abiotic metals As, Pb, Al and Cd. Significant increase in extracellular siderophore production was observed with Pb and Al at concentrations of 50 μM and above. The effect of metals on siderophore production was completely mitigated in presence of Fe. The results implicate effect of metals on the efficiency of siderophore production by bacteria for potential application in bioremediation of metal contaminated iron deficient soils especially in the microbial assisted phytoremediation processes.

  17. Growth of 48 built environment bacterial isolates on board the International Space Station (ISS).

    Science.gov (United States)

    Coil, David A; Neches, Russell Y; Lang, Jenna M; Brown, Wendy E; Severance, Mark; Cavalier, Darlene; Eisen, Jonathan A

    2016-01-01

    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.

  18. Isolated Bacterial Spores at High-velocity Survive Surface Impacts in Vacuum

    Science.gov (United States)

    Austin, Daniel; Barney, Brandon

    We present experiments in which bacterial spores were found to survive being accelerated in vacuum to velocities in the range 30-120 m/s and impacted on a dense target. In these experiments, spores of Bacillus subtilis spores were charged using electrospray at atmospheric pressure, dried, and then introduced into high vacuum. Through choice of skimmers and beam tubes, different velocity ranges were achieved. An image-charge detector observed the charged spores, providing total charge and velocity. The spores then impacted a glass target within a collection vessel. After the experiment, the collection vessel contents were extracted and cultured. Several positive and negative controls were used, including the use of antibiotic-resistant spores and antibiotic-containing (rifampicin) agar for culturing. These impact velocities are of particular interest for possible transport of bacterial spores from Mars to Phobos, and may have implications for planetary protection in a Phobos sample return mission. In addition, bacteria may reach similar velocities during a spacecraft crash (e.g., within components, or from spacecraft to surface materials during impact, etc.), raising concerns about forward contamination. The velocities of interest to transport of life between planets (panspermia) are somewhat higher, but these results complement shock-based experiments and contribute to the general discussion of impact survivability of organisms.

  19. 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.

  20. 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.

  1. ‘Flaviflexus massiliensis’, a new bacterial species isolated from the human gut

    Directory of Open Access Journals (Sweden)

    S.I. Traore

    2016-11-01

    Full Text Available Herein, we report the main characteristics of ‘Flaviflexus massiliensis’ strain SIT4T (CSURP1300, a new bacterium that was isolated from the stool specimen of a 2-year-old girl from Niger suffering from kwashiorkor.

  2. Genome Sequences of 12 Bacterial Isolates Obtained from the Urine of Pregnant Women

    Science.gov (United States)

    Weimer, Cory M.; Deitzler, Grace E.; Robinson, Lloyd S.; Park, SoEun; Hallsworth-Pepin, Kymberlie; Wollam, Aye; Mitreva, Makedonka

    2016-01-01

    The presence of bacteria in urine can pose significant risks during pregnancy. However, there are few reference genome strains for many common urinary bacteria. We isolated 12 urinary strains of Streptococcus, Staphylococcus, Citrobacter, Gardnerella, and Lactobacillus. These strains and their genomes are now available to the research community. PMID:27688327

  3. Isolation of DNA from bacterial samples of the human gastrointestinal tract

    NARCIS (Netherlands)

    Zoetendal, E.G.; Heilig, G.H.J.; Klaassens, E.S.; Booijink, C.C.G.M.; Kleerebezem, M.; Smidt, H.; Vos, de W.M.

    2006-01-01

    The human gastrointestinal (GI) tract contains a complex microbial community that develops in time and space. The most widely used approaches to study microbial diversity and activity are all based on the analysis of nucleic acids, DNA, rRNA and mRNA. Here, we present a DNA isolation protocol that i

  4. A survey on species and prevalence rate of bacterial agents isolated from cockroaches in three hospitals.

    Science.gov (United States)

    Zarchi, Ali Akbar Karimi; Vatani, Hadi

    2009-04-01

    The presence of cockroaches has health implications, such as nosocomial infection, as the insects move freely from areas within and around hospitals that may harbor pathogenic organisms. The goals of the present study were to determine species of bacteria isolated from cockroaches found in three Tehran hospitals, and to determine distribution of potential vectors by species and sex. The study is descriptive laboratory research. A total of 305 cockroaches from three species were trapped and identified: Periplaneta americana (65.6%), Blatella germanica (12.1%), and Blatta orientalis (22.3%). From these potential vectors, 19 species of bacteria were isolated and identified. After transportation of cockroaches to the laboratory, separation of the whole-homogenized suspension of each species was carried out. Identification of the isolated bacteria was performed according to Burgey's Manual of Determinative Bacteriology, 9th Edition. The most common species of bacteria isolated from cockroaches were Escherichia coli, Streptococcus Group D, Bacillus spp., Klebsiella pneumoniae, and Proteus vulgaris. No statistical significance was found between sex and species of cockroach carrying bacteria (p > 0.05), but significance was found for sex in Citrobacter freundii, Staphylococcus aureus, and Streptococcus non-group A&B (p < 0.05).

  5. 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...

  6. 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)

  7. Antibacterial efficacy of the seed extracts of Melia azedarach against some hospital isolated human pathogenic bacterial strains

    Institute of Scientific and Technical Information of China (English)

    Abdul Viqar Khan; Qamar Uddin Ahmed; M Ramzan Mir; Indu Shukla; Athar Ali Khan

    2011-01-01

    To investigate the antibacterial potential of the polar and non-polar extracts of the seeds of Melia azedarach (M. azedarach) L. (Meliaceae) against eighteen hospital isolated human pathogenic bacterial strains. Methods: Petrol, benzene, ethyl acetate, methanol, and aqueous extracts at five different concentrations (1, 2, 5, 10 and 15 mg/mL) were evaluated. Disk diffusion method was followed to evaluate the antibacterial efficacy. Results: All extracts of the seeds demonstrated significant antibacterial activity against tested pathogens. Among all extracts, ethyl acetate extract revealed the highest inhibition comparatively. The present study also favored the traditional uses reported earlier. Conclusions: Results of this study strongly confirm that the seed extracts of M. azedarach could be effective antibiotics, both in controlling gram-positive and gram-negative human pathogenic infections.

  8. Effect of PGR producing bacterial strains isolated from vermisources on germination and growth of Vigna unguiculata (L. Walp.

    Directory of Open Access Journals (Sweden)

    Anandharaj Marimuthu

    2014-12-01

    Full Text Available Nineteen bacterial strains were isolated from vermisources andscreened for Indole-3-acetic acid (IAA production among themonly nine strains produce IAA and they were identified asStreptococcus spp., Micrococcus spp., Klebsiella spp., Bacillus spp., Enterobacter spp., Escherichia spp., Alcaligenes spp., Erwinia spp., and Pseudomonas spp. Among all other strains Bacillus sp. showed the higher IAA production hence selected for further molecular analysis and confirmed as Bacillus cereus. The B. cereus was grown in nutrient broth supplemented with different concentrations (1, 2, 3, 4 and 5mg/ml of tryptophan for seven days at pH 7 and at 37ºC. Crude IAA was used for in vitro phytostimulatory studies using Vigna unguiculata (L. Walp. The plant growth parameters were analyzed at different day intervals (5, 10 and 15 days. Supplementation of 5 ml crude IAA (2mg/ml of tryptophan dynamically enhances the plant growth parameters after 15 days.

  9. 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.

  10. 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.

  11. 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.

  12. Aerobic De-Epoxydation of Trichothecene Mycotoxins by a Soil Bacterial Consortium Isolated Using In Situ Soil Enrichment

    Science.gov (United States)

    He, Wei-Jie; Yuan, Qing-Song; Zhang, You-Bing; Guo, Mao-Wei; Gong, An-Dong; Zhang, Jing-Bo; Wu, Ai-Bo; Huang, Tao; Qu, Bo; Li, He-Ping; Liao, Yu-Cai

    2016-01-01

    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. PMID:27669304

  13. [Isolation and identification of Gardnerella vaginalis in women with symptoms of bacterial vaginosis].

    Science.gov (United States)

    León, X; Ruiz, M; de Moreno, N O; de Richards, L

    1992-09-01

    70 samples of vaginal secretions were collected from women with bacterial vaginosis syndrome, that were attended in Nuevo Veranillo' Health Center. All samples were tested in order to determinate the presence of amine and to Gram'methods stain to observe the morphologic characteristics of the "Clue" cells (epithelial cells with adhered bacteria). Samples were cultured in a selective media of blood agar in Columbia base with colistine and nalidixic acid, and incubated in an environment of CO2 at 37 degrees C. Tests of oxidase, catalase, glucid fermentation, hippurate hydrolysis and starch hydrolysis were made on the grown colonies. 27 out of 70 samples resulted in positive cultures for Gardnerella vaginalis, 11 to pregnant women and 16 to nonpregnant women; among these, 14 women used some kind of contraceptive methods as DIU or pill.

  14. Isolation and characteristics analysis of a novel high bacterial cellulose producing strain Gluconacetobacter intermedius CIs26.

    Science.gov (United States)

    Yang, Ying; Jia, Jingjing; Xing, Jianrong; Chen, Jianbing; Lu, Shengmin

    2013-02-15

    A strain producing bacterial cellulose (BC) screened from rotten mandarin fruit was identified as Gluconacetobacter intermedius CIs26 by the examination of general taxonomical characteristics and 16S rDNA sequence analysis. Furthermore, Fourier transform infrared (FT-IR) spectrum showed that pellicle produced by strain CIs26 was composed of glucan, and had the same functional group as a typical BC. X-ray diffractometry (XRD) analysis indicated that the BC was type I in structure with crystallinity index of 75%. BC yields of strain CIs26 in Hestrin-Schramn (HS), citrus waste modified HS (CMHS) and citrus waste solution (CWS) mediums were 2.1 g/L, 5.7 g/L, and 7.2 g/L, respectively. It was shown that citrus waste could stimulate BC production of strain CIs26 efficiently. Based on the ability of utilization of citrus waste, this strain appeared to have potential in BC manufacture on an industrial scale.

  15. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Barnali Paul

    2013-05-01

    Full Text Available 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 (MIC of 3,4 dihydroxy cinnamic acid was also recorded against those bacteria by serial dilution technique. Kanamycin was used as positive control. Results showed that 3,4 dihydroxy cinnamic acid had antibacterial activity against the tested bacteria.

  18. Increasing Ciprofloxacin Resistance Among Prevalent Urinary Tract Bacterial Isolates in Gaza Strip, Palestine

    Directory of Open Access Journals (Sweden)

    Zakaria El Astal

    2005-01-01

    Full Text Available This article presents the incidence of ciprofloxacin resistance among 480 clinical isolates obtained from patients with urinary tract infection (UTI during January to June 2004 in Gaza Strip, Palestine. The resistance rates observed were 15.0% to ciprofloxacin, 82.5% to amoxycillin, 64.4% to cotrimoxazole, 63.1% to doxycycline, 32.5% to cephalexin, 31.9% to nalidixic acid, and 10.0% to amikacin. High resistance to ciprofloxacin was detected among Acinetobacter haemolyticus (28.6%, Staphylococcus saprophyticus (25.0%,Pseudomonas aeruginosa (20.0%, Klebsiella pneumonia (17.6%, and Escherichia coli (12.0%. Minimal inhibitory concentration (MIC of ciprofloxacin evenly ranged from 4 to 32 μg/mL with a mean of 25.0 μg/mL. This study indicates emerging ciprofloxacin resistance among urinary tract infection isolates. Increasing resistance against ciprofloxacin demands coordinated monitoring of its activity and rational use of the antibiotics.

  19. Interactions of antibiotics and methanolic crude extracts of Afzelia Africana (Smith.) against drug resistance bacterial isolates.

    Science.gov (United States)

    Aiyegoro, Olayinka; Adewusi, Adekanmi; Oyedemi, Sunday; Akinpelu, David; Okoh, Anthony

    2011-01-01

    Infection due to multidrug resistance pathogens is difficult to manage due to bacterial virulence factors and because of a relatively limited choice of antimicrobial agents. Thus, it is imperative to discover fresh antimicrobials or new practices that are effective for the treatment of infectious diseases caused by drug-resistant microorganisms. The objective of this experiment is to investigate for synergistic outcomes when crude methanolic extract of the stem bark of Afzelia africana and antibiotics were combined against a panel of antibiotic resistant bacterial strains that have been implicated in infections. Standard microbiological protocols were used to determine the minimum inhibitory concentrations (MICs) of the extract and antibiotics, as well as to investigate the effect of combinations of the methanolic extract of A. africana stem bark and selected antibiotics using the time-kill assay method. The extract of Afzelia africana exhibited antibacterial activities against both Gram-negative and Gram-positive bacteria made up of environmental and standard strains at a screening concentration of 5 mg/mL. The MICs of the crude extracts and the antibiotics varied between 1 μg/mL and 5.0 mg/mL. Overall, synergistic response constituted about 63.79% of all manner of combinations of extract and antibiotics against all test organisms; antagonism was not detected among the 176 tests carried out. The extract from A. africana stem bark showed potentials of synergy in combination with antibiotics against strains of pathogenic bacteria. The detection of synergy between the extract and antibiotics demonstrates the potential of this plant as a source of antibiotic resistance modulating compounds.

  20. Physico-chemical surface characterization of a bacterial population isolated from a milking machine

    OpenAIRE

    Teixeira, P.; Lopes, Zulmira; Azeredo, Joana; Oliveira, Rosário; Vieira, M. J.

    2005-01-01

    The hydrophobicity of 26 species of bacteria representative of the main genera isolated from a rubber short milk tube, which is a constituent of a cluster from a milking machine, was determined. The materials forming the cluster namely rubber, stainless steel (SS) 316, stainless steel (SS) 304, glass and polymethylmethacrylate (PMMA) were also assayed in terms of hydrophobicity. In relation with the hydrophobicity of bacteria, all the strains of Lactobacillus lactis lactis as well as...

  1. Identification and physicochemical characterization of bacterial surface isolated from catering services in health establishment

    Directory of Open Access Journals (Sweden)

    Khadija Azelmad

    2016-12-01

    Full Text Available The initial interaction between microorganisms and substrata is mediated by physicochemical forces, which originate from the physicochemical surface properties of both interacting surfaces. In this context, we have determined the physicochemical proprieties (hydrophobicity, electron-donor and electron-acceptor of 37 isolates belonging to three genres of bacteria: Pseudomonas spp., Staphylococcus spp. and some species of Enterobacteriaceae isolated from various surfaces of the equipment and materials used in health establishment catering services. The physicochemical properties of these isolates were determined by contact angles measurements via Sessile Drop Technique. The results revealed that 62% of all bacteria studied exhibit a hydrophilic character (ΔGiwi >0 and other strains have a hydrophobic character (ΔGiwi <0. Also the results show that all strains have a high electron donor character (high γ- (ranging from 22.8 mJ.m-2 to 105.4 mJ.m-2. Forty one percent of these strains have a high electron acceptor (γ+ (ranging from 14.7 mJ.m-2 to 34.6 mJ.m-2 and the others express a low electron acceptor character.

  2. 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.

  3. A positive correlation between bacterial autoaggregation and biofilm formation in native Sinorhizobium meliloti isolates from Argentina.

    Science.gov (United States)

    Sorroche, Fernando G; Spesia, Mariana B; Zorreguieta, Angeles; Giordano, Walter

    2012-06-01

    Sinorhizobium meliloti is a symbiotic nitrogen-fixing bacterium that elicits nodule formation on roots of alfalfa plants. S. meliloti produces two exopolysaccharides (EPSs), termed EPS I and EPS II, that are both able to promote symbiosis. EPS I and EPS II are secreted in two major fractions that reflect differing degrees of subunit polymerization, designated high- and low-molecular-weight fractions. We reported previously that EPSs are crucial for autoaggregation and biofilm formation in S. meliloti reference strains and isogenic mutants. However, the previous observations were obtained by use of "domesticated" laboratory strains, with mutations resulting from successive passages under unnatural conditions, as has been documented for reference strain Rm1021. In the present study, we analyzed the autoaggregation and biofilm formation abilities of native S. meliloti strains isolated from root nodules of alfalfa plants grown in four regions of Argentina. 16S rRNA gene analysis of all the native isolates revealed a high degree of identity with reference S. meliloti strains. PCR analysis of the expR gene of all the isolates showed that, as in the case of reference strain Rm8530, this gene is not interrupted by an insertion sequence (IS) element. A positive correlation was found between autoaggregation and biofilm formation abilities in these rhizobia, indicating that both processes depend on the same physical adhesive forces. Extracellular complementation experiments using mutants of the native strains showed that autoaggregation was dependent on EPS II production. Our results indicate that a functional EPS II synthetic pathway and its proper regulation are essential for cell-cell interactions and surface attachment of S. meliloti.

  4. Bacillus rubiinfantis sp. nov. strain mt2T, a new bacterial species isolated from human gut

    Directory of Open Access Journals (Sweden)

    M. Tidjiani Alou

    2015-11-01

    Full Text Available Bacillus rubiinfantis sp. nov. strain mt2T is the type strain of B. rubiinfantis sp. nov., isolated from the fecal flora of a child with kwashiorkor in Niger. It is Gram-positive facultative anaerobic rod belonging to the Bacillaceae family. We describe the features of this organism alongside the complete genome sequence and annotation. The 4 311 083 bp long genome (one chromosome but no plasmid contains 4028 protein-coding gene and 121 RNA genes including nine rRNA genes.

  5. 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.

  6. 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.

  7. 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.

  8. Antimicrobial Evaluation of Bacterial Isolates from Urine Specimen of Patients with Complaints of Urinary Tract Infections in Awka, Nigeria

    Science.gov (United States)

    Ekwealor, Perpetua A.; Ugwu, Malachy C.; Ezeobi, Ifeanyi; Amalukwe, George; Ugwu, Belinda C.; Okezie, Ugochukwu; Stanley, Catherine; Esimone, Charles

    2016-01-01

    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. PMID:27200093

  9. A Multi-Unit Project for Building Scientific Confidence via Authentic Research in Identification of Environmental Bacterial Isolates

    Directory of Open Access Journals (Sweden)

    Christa Chatfield

    2014-08-01

    Full Text Available This authentic research project is designed to identify environmental isolates by metabolic phenotypes and 16s sequence analysis and with an investigation of biofilm growth is presented as implemented in an upper-level microbiology lab course. Three units were used in the lab: one for basic metabolic identification, one for the 16s rDNA sequencing and a third for biofilm growth analysis. Assessment was by weekly notebook entries detailing the outcomes of each day in lab, providing relatively on-time feedback on student understanding and learning to both the student and the instructor. The intent for these units was for each to increase the uncertainty of the project outcomes and to challenge students to design projects with open-ended results. All student groups have been able to obtain DNA sequence data in the limited 6-7 weeks of the lab project. Students report increased confidence in their abilities and a general excitement about the project methods and results. The data produced by the students can be incorporated into larger research questions posed by the faculty running the course as determined by the source of the unknown bacterial isolates.

  10. Isolation and characterization of a novel violacein-like pigment producing psychrotrophic bacterial species Janthinobacterium svalbardensis sp. nov.

    Science.gov (United States)

    Ambrožič Avguštin, Jerneja; Žgur Bertok, Darja; Kostanjšek, Rok; Avguštin, Gorazd

    2013-04-01

    A bacterial strain designated JA-1, related to Janthinobacterium lividum, was isolated from glacier ice samples from the island Spitsbergen in the Arctic. The strain was tested for phenotypic traits and the most prominent appeared to be the dark red brown to black pigmentation different from the violet pigment of Janthinobacterium, Chromobacterium and Iodobacter. Phylogenetic analysis based on 16S rRNA gene sequences and DNA-DNA hybridization tests showed that strain JA-1 belongs to the genus Janthinobacterium but represents a novel lineage distinct from the two known species of this genus, J. lividum and Janthinobacterium agaricidamnosum. The DNA G + C content of strain JA-1 was determined to be 62.3 mol %. The isolate is a psychrotrophic Gram negative bacterium, rod-shaped with rounded ends, containing intracellular inclusions and one polar flagellum. On the basis of the presented results strain JA-1 is proposed as the type strain of a novel species of the genus Janthinobacterium, for which the name Janthinobacterium svalbardensis sp. nov. is proposed (JA-1(T) = DSM 25734, ZIM B637).

  11. Isolation and characterization of an efficient bacterial cellulose producer strain in agitated culture: Gluconacetobacter hansenii P2A.

    Science.gov (United States)

    Aydın, Yasar Andelib; Aksoy, Nuran Deveci

    2014-02-01

    In this study, typical niches of acetic acid bacteria were screened for isolation of cellulose producer strains. Hestrin Schramm broth was used as enrichment and production media. Only nine out of 329 isolates formed thick biofilms on liquid surface and were identified as potential cellulose producers. Physiological and biochemical tests proved that all cellulose producers belonged to Gluconacetobacter genus. Most productive and mutation-resistant strain was subjected to 16S rRNA sequence analysis and identified as Gluconacetobacter hansenii P2A due to 99.8 % sequence similarity. X-ray diffraction analysis proved that the biofilm conformed to Cellulose I crystal structure, rich in Iα mass fraction. Static cultivation of G. hansenii P2A in HS medium resulted with 1.89 ± 0.08 g/l of bacterial cellulose production corresponding to 12.0 ± 0.3 % yield in terms of substrate consumption. Shaking and agitation at 120 rpm aided in enhancement of the amount and yield of produced cellulose. Productivity and yield reached up to 3.25 ± 0.11 g/l and 17.20 ± 0.14 % in agitated culture while a slight decrease from 78.7 % to 77.3 % was observed in the crystallinity index.

  12. 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)).

  13. A small-scale, low-cost isolation system for the incubation and rearing of low bacterial load chicks as a model to study microbial-intestinal interactions.

    Science.gov (United States)

    Forder, Rebecca E A; Firth, Gordon A; Tivey, David R; Howarth, Gordon S; Hughes, Robert J

    2008-04-01

    A small-scale, economical isolator system was adapted to hatch and raise chicks in a bacteria-free environment as a means to observe bacterial interactions with the intestinal mucosa during early development. The design and construction of flexible plastic isolators for incubation and brooding are described along with methodologies for preparation of eggs for entry into the isolators, incubation and hatching. Two trials were conducted, the first in August 2005 and the second in March 2006. Results from both trials showed no differences in body weights of chicks raised in isolation when compared with those raised conventionally. Growth of bacteria was detected from rectal swabs at day 2 post-hatch, with both trials, showing a light growth of Bacillus sp., coagulase-negative staphylococci and haemolytic streptococcus in trial 1, and a light growth of Bacillus cereus only in trial 2. Although not germfree, the growth of bacteria in chicks raised in isolation was decreased or absent when compared with chicks raised conventionally. Feed was negative for contamination and surface swabs of equipment were also negative until day 3 post-hatch, suggesting possible contamination within the eggs themselves. Despite the presence of bacterial species, the isolator system was successful in producing low bacterial load chicks for comparison studies with conventionally raised chicks.

  14. 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.

    2016-01-01

    Summary 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 global carbon fixation and 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 an unusual compartment designed by nature to optimize metabolic processes within a cellular context. PMID:26148529

  15. 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.

  16. 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.

  17. Isolation, characterization and phylogenetic analysis of a bacterial strain capable of degrading acetamiprid

    Institute of Scientific and Technical Information of China (English)

    YAO Xiao-hua; MIN Hang

    2006-01-01

    An aerobic bacterium, capable of degrading the new chloronicotine pesticide acetamiprid, was isolated from the sludge of pesticide factory after successive enrichment cultures and named strain FH2 which is a Gram-negative, rod-shaped, obligate aerobic organism with ((0.5-0.7) ×(1.5-3.0))μm of cell size and with monotrichous flagellum. It was identified as a member of Pseudomonas sp. based on morphology, physio-biochemical properties, Biolog GN2, 16S rDNA sequence and phylogenetic characteristic analysis. The isolate could grow optimally at pH 7.0 and 30℃ in acetamiprid-mineral medium with 800 mg/L concentration. About 53.3% acetamiprid was degraded by strain FH2 after incubation for 14 d in acetamiprid-mineral medium and nearly 96.7% degraded when incubated in acetamiprid-yeast mineral medium at 30℃ for 14 d. This paper describes phylogenetic and degradation characterization of a pure bacterium being able to mineralize acetamiprid for the first time.

  18. ISOLATION AND CHARACTERIZATION OF HALOPHILIC BACTERIAL STRAINS FROM SALINE WATERS OF KHEWRA SALT MINES ON THE BASIS OF 16S rRNA GENE SEQUENCE

    Directory of Open Access Journals (Sweden)

    Muhammad Kaleem Sarwar

    2014-02-01

    Full Text Available Halophiles are salt loving microbes optimally growing at high concentrations of salt. Khewra salt mines of Pakistan provide extreme saline conditions where enormous halophilic microbial biota thrives. The present study aimed at isolation and molecular identification of bacterial strains from saline waters of Khewra salt mines. Using halophilic media, nine halophilic bacterial strains from saline water bodies were cultured and studied under optimized growth conditions (NaCl, pH and temperature. Bacterial growth at different NaCl concentrations was measured at 600nm wavelength, showing optimal growth at 1.5M NaCl. 769bp size 16S rRNA gene was amplified for molecular identification of bacterial strains. The amplified genes of the strains FA2.2 and FA3.3 were sequenced and their homology with other bacterial strains was analyzed. The results showed FA2.2 shared maximum homology with Bacillus anthracis strain while FA3.3 showed close resemblance with Staphylococcus saprophyticus subsp. bovis. Isolated halophilic bacterial strains possess potential for various biotechnological applications. They could be manipulated for synthesizing transgenic crops tolerating high salinity boosting the agricultural yield. Moreover extremozymes of these bacteria holds great industrial importance.

  19. 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.

  20. Identification of bacterial isolates obtained from intestinal contents associated with 12,000-year-old mastodon remains.

    Science.gov (United States)

    Rhodes, A N; Urbance, J W; Youga, H; Corlew-Newman, H; Reddy, C A; Klug, M J; Tiedje, J M; Fisher, D C

    1998-02-01

    Mastodon (Mammut americanum) remains unearthed during excavation of ancient sediments usually consist only of skeletal material, due to postmortem decomposition of soft tissues by microorganisms. Two recent excavations of skeletal remains in anoxic sediments in Ohio and Michigan, however, have uncovered organic masses which appear to be remnants of the small and large intestines, respectively. Macrobotanical examinations of the composition of these masses revealed assemblages of plant material radiocarbon dated to approximately 11,500 years before the present and thought to be incompletely digested food remains from this extinct mammal. We attempted to cultivate and identify bacteria from the intestinal contents, bone-associated sediments, and sediments not in proximity to the remains using a variety of general and selective media. In all, 295 isolates were cultivated, and 38 individual taxa were identified by fatty acid-methyl ester (FAME) profiles and biochemical characteristics (API-20E). The taxonomic positions of selected enteric and obligately anaerobic bacteria were confirmed by 16S ribosomal DNA (rDNA) sequencing. Results indicate that the intestinal and bone-associated samples contained the greatest diversity of bacterial taxa and that members of the family Enterobacteriaceae represented 41% of all isolates and were predominant in the intestinal masses and sediments in proximity to the skeleton but were uncommon in the background sediments. Enterobacter cloacae was the most commonly identified isolate, and partial rDNA sequencing revealed that Rahnella aquatilis was the correct identity of strains suggested by FAME profiles to be Yersinia enterocolitica. No Bacteroides spp. or expected intestinal anaerobes were recovered. The only obligate anaerobes recovered were clostridia, and these were not recovered from the small intestinal masses. Microbiological evidence from this study supports other, macrobotanical data indicating the intestinal origin of these

  1. Usefulness of the MicroSeq 500 16S rDNA bacterial identification system for identification of anaerobic Gram positive bacilli isolated from blood cultures

    National Research Council Canada - National Science Library

    Lau, S K P; Ng, K H L; Woo, P C Y; Yip, K-T; Fung, A M Y; Woo, G K S; Chan, K-M; Que, T-L; Yuen, K-Y

    2006-01-01

    Using full 16S ribosomal RNA (rRNA) gene sequencing as the gold standard, 20 non-duplicating anaerobic Gram positive bacilli isolated from blood cultures were analysed by the MicroSeq 500 16S rDNA bacterial identification system...

  2. ‘Khoudiadiopia massiliensis’ gen. nov., sp. nov., strain Marseille-P2746TT, a new bacterial genus isolated from the female genital tract

    Directory of Open Access Journals (Sweden)

    A. Diop

    2017-09-01

    Full Text Available We report the main characteristics of ‘Khoudiadiopia massiliensis’ gen. nov., sp. nov., strain Marseille-P2746T (= CSUR P2746, a new member of the Peptoniphilaceae family isolated from a vaginal swab of a patient suffering from bacterial vaginosis.

  3. Gram-negative bacterial isolates from fresh-cut processing plants enhance the presence of Escherichia Coli O157:H7 in dual-species biofilms

    Science.gov (United States)

    Biofilms formed by resident microflora may provide a microenvironment for foodborne bacterial pathogens to survive and cause cross-contamination in fresh-cut processing and handling facilities. The objective of this study is to determine the impact of individual bacteria strains isolated from two l...

  4. Complete Genome Sequence of Lactobacillus jensenii Strain SNUV360, a Probiotic for Treatment of Bacterial Vaginosis Isolated from the Vagina of a Healthy Korean Woman

    Science.gov (United States)

    Lee, Sunghee; You, Hyun Ju; Kwon, Bomi

    2017-01-01

    ABSTRACT Lactobacillus jensenii SNUV360 is a potential probiotic strain that shows antimicrobial activity for the treatment of bacterial vaginosis. Here, we present the complete genomic sequence of L. jensenii SNUV360, isolated from a vaginal sample from a healthy Korean woman. Analysis of the sequence may provide insight into its functional activity. PMID:28280032

  5. Selected lactic acid-producing bacterial isolates with the capacity to reduce Salmonella translocation and virulence gene expression in chickens.

    Directory of Open Access Journals (Sweden)

    Xiaojian Yang

    Full Text Available BACKGROUND: Probiotics have been used to control Salmonella colonization/infection in chickens. Yet the mechanisms of probiotic effects are not fully understood. This study has characterized our previously-selected lactic acid-producing bacterial (LAB isolates for controlling Salmonella infection in chickens, particularly the mechanism underlying the control. METHODOLOGY/PRINCIPAL FINDINGS: In vitro studies were conducted to characterize 14 LAB isolates for their tolerance to low pH (2.0 and high bile salt (0.3-1.5% and susceptibility to antibiotics. Three chicken infection trials were subsequently carried out to evaluate four of the isolates for reducing the burden of Salmonella enterica serovar Typhimurium in the broiler cecum. Chicks were gavaged with LAB cultures (10(6-7 CFU/chick or phosphate-buffered saline (PBS at 1 day of age followed by Salmonella challenge (10(4 CFU/chick next day. Samples of cecal digesta, spleen, and liver were examined for Salmonella counts on days 1, 3, or 4 post-challenge. Salmonella in the cecum from Trial 3 was also assessed for the expression of ten virulence genes located in its pathogenicity island-1 (SPI-1. These genes play a role in Salmonella intestinal invasion. Tested LAB isolates (individuals or mixed cultures were unable to lower Salmonella burden in the chicken cecum, but able to attenuate Salmonella infection in the spleen and liver. The LAB treatments also reduced almost all SPI-1 virulence gene expression (9 out of 10 in the chicken cecum, particularly at the low dose. In vitro treatment with the extracellular culture fluid from a LAB culture also down-regulated most SPI-1 virulence gene expression. CONCLUSIONS/SIGNIFICANCE: The possible correlation between attenuation of Salmonella infection in the chicken spleen and liver and reduction of Salmonella SPI-1 virulence gene expression in the chicken cecum by LAB isolates is a new observation. Suppression of Salmonella virulence gene expression in

  6. Differentiation of environmental aquatic bacterial isolates by MALDI-TOF MS.

    Science.gov (United States)

    Popović, Natalija Topić; Kazazić, Snježana P; Strunjak-Perović, Ivančica; Čož-Rakovac, Rozelindra

    2017-01-01

    Identification of bacteria in aquatic and environmental applications, for monitoring purposes and research, for health assessments and therapy considerations of farmed and free-living aquatic organisms, still relies on conventional phenotypic and biochemical protocols. Although molecular techniques based on DNA amplification and sequencing are finding ways into diagnostic laboratories, they are time-consuming, costly and difficult in the case of multiplex assays. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate proteomic method reliable for identification of unknown bacteria to the genus and species level. Upon extension of databases, it will certainly find its position in environmental sciences. The paper presents an overview of the principle of the method, its effectiveness in comparison with conventional and molecular identification procedures, and applicability on environmental and aquatic isolates, discussing its advantages and shortcomings, as well as possible future implementations.

  7. 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.

  8. 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.

  9. Interaction of legionella pneumophila and helicobacter pylori with bacterial species isolated from drinking water biofilms

    Directory of Open Access Journals (Sweden)

    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.

  10. 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

    Directory of Open Access Journals (Sweden)

    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.

  11. 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

    Recent years have seen renewed interest in phage therapy - the use of viruses to specifically kill disease-causing bacteria – because of the alarming rise in antibiotic resistance. However, a major limitation of phage therapy is the ease at with bacteria can evolve resistance to phages. Here we...... determined if in vitro experimental coevolution can increase the efficiency of phage therapy by limiting the resistance evolution of intermittent and chronic cystic fibrosis Pseudomonas aeruginosa lung isolates to four different phages. We first pre-adapted all phage strains against all bacterial strains...... 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...

  12. Biodegradation of free cyanide by bacterial species isolated from cyanide-contaminated artisanal gold mining catchment area in Burkina Faso.

    Science.gov (United States)

    Razanamahandry, Lovasoa Christine; Andrianisa, Harinaivo Anderson; Karoui, Hela; Kouakou, Koffi Marcelin; Yacouba, Hamma

    2016-08-01

    Soil and water samples were collected from a watershed in Burkina Faso where illegal artisanal gold extraction using cyanidation occurs. The samples were used to evaluate cyanide contamination and the presence of cyanide degrading bacteria (CDB). Free cyanide (F-CN) was detected in all samples, with concentrations varying from 0.023 to 0.9 mg kg(-1), and 0.7-23 μg L(-1) in the soil and water samples, respectively. Potential CDB also were present in the samples. To test the effective F-CN degradation capacity of the isolated CDB species, the species were cultivated in growth media containing 40, 60 or 80 mg F-CN L(-1), with or without nutrients, at pH 9.5 and at room temperature. More than 95% of F-CN was degraded within 25 h, and F-CN degradation was associated with bacterial growth and ammonium production. However, initial concentrations of F-CN higher than 100 mg L(-1) inhibited bacterial growth and cyanide degradation. Abiotic tests showed that less than 3% of F-CN was removed by volatilization. Thus, the degradation of F-CN occurred predominately by biological mechanisms, and such mechanisms are recommended for remediation of contaminated soil and water. The bacteria consortium used in the experiment described above exist in a Sahelian climate, which is characterized by a long hot and dry season. Because the bacteria are already adapted to the local climate conditions and show the potential for cyanide biodegradation, further applicability to other contaminated areas in West Africa, where illegal gold cyanidation is widespread, should be explored. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Comparative analysis of tertiary alcohol esterase activity in bacterial strains isolated from enrichment cultures and from screening strain libraries.

    Science.gov (United States)

    Herter, Susanne; Nguyen, Giang-Son; Thompson, Mark L; Steffen-Munsberg, Fabian; Schauer, Frieder; Bornscheuer, Uwe T; Kourist, Robert

    2011-05-01

    The preparation of enantiopure tertiary alcohols is of great contemporary interest due to the application of these versatile building blocks in organic synthesis and as precursors towards high value pharmaceutical compounds. Herein, we describe two approaches taken towards the discovery of novel biocatalysts for the synthesis of these valuable compounds. The first approach was initiated with screening of 47 bacterial strains for hydrolytic activity towards the simple tertiary alcohol ester tert-butyl acetate. In conjunction, a second method focussed on the isolation of strains competent for growth on tert-butyl acetate as the sole source of carbon and energy. From functional screening, 10 Gram-positive Actinomycetes showed hydrolytic activity, whilst enrichment selection resulted in the identification of 14 active strains, of which five belong to the Gram-negative cell-wall type. Bacterial strains obtained from both approaches were viable for enantioselective hydrolysis of pyridine substituted tertiary alcohol esters in addition to bulky aliphatic and keto-derived substrates from the same class. Activity towards each of the test substrates was uncovered, with promising enantioselectivities of up to E = 71 in the hydrolysis of a para-substituted pyridine tertiary alcohol ester using a strain of Rhodococcus ruber. Interestingly strains of Microbacterium and Alcaligenes sp. gave opposite enantiopreference in the hydrolysis of a meta-substituted pyridine tertiary alcohol ester with E values of 17 and 54. These approaches show that via both possibilities, screening established strain collections and performing enrichment selection, it is possible to identify novel species which show activity towards sterically challenging substrates.

  14. [Isolation and identification of a bacterial strain JS018 capable of degrading several kinds of organophosphate pesticides].

    Science.gov (United States)

    Jiang, Yu-Ji; Deng, You-Jin; Liu, Xin-Rui; Xie, Bao-Gui; Hu, Fang-Ping

    2006-06-01

    Organophosphate pesticides are used widely all over the world and play an important role in plant pest control. However these pesticides are considered as pollutants and harmful to human health. To search for microorganisms that can degrade organophosphate pesticides with high efficiency, a bacterial strain, coded as JS018, was isolated and screened from the soil in the vicinity of Shanming Pesticides Factory, Shanming, Fujian. Laboratory tests showed that the bacterium could degrade several kinds of organophosphate pesticides, such as Parathion-methyl and phoxin. The strain's degrading rates on phoxin, Parathion-methyl, hostathion and dichlorvos in LB liquid fermentation medium for 36 h were 99%, 96%, 80.4% and 69.0% respectively. The bacterial colonies on LB plate appeared shiny and pale-pink in color. The bacteria were Gram-negative coccoids, 0.5 - 0.7 microm in diameter. They grew well at 30 - 38 degrees C and pH 7.0 - 9.0. The optimal temperature and pH for cell growth was 32 degrees C and pH 7.5 - 8.0, respectively. They did not grow in medium containing 6% or more NaCl. The antibiotic susceptibility tests showed that the strain was resistant to ampicillin, penicillin and lincomycin. It was sensitive to kanamycin, tetracycline and gentamicin. Laboratory tests also showed that the strain could ferment D-glucose, trehalose, melezitose and ethanol. It was negative in the production of indole and hydrogen sulfide. It could not liquefy gelatin, utilize citrate, nor ferment L-arabinose, sucrose, D-mannitol, D-xylose, fructose, D-galactose, maltose or lactose. The catalase, urease and nitrate reduction were positive. Based on its morphological, physiological and biochemical properties as well as the 16S rDNA sequence analysis result, the strain was tentatively identified as Roseomonas sp.

  15. Susceptibility pattern of some clinical bacterial isolates to selected antibiotics and disinfectants.

    Science.gov (United States)

    Ogbulie, Jude N; Adieze, Ifechukwu E; Nwankwo, Ngozi C

    2008-01-01

    The antibacterial activities of five antibiotics, three brands of Ofloxacins (Obenasin, Floxavid and Drovid) and two brands of Ciprofloxacins (Uroxin and Siprosan), and five commonly used disinfectants (Lysol, Dettol, Purit, Roberts and Wex-cide) against Staphylococcus aureus, Escherichia coli, Proteus spp., Pseudomonas aeruginosa, Streptococcus spp. and Bacillus spp. were investigated. The growth inhibitory effect of both the antibiotics and disinfectants were determined using paper disk diffusion method and well-in-agar technique respectively. The highest mean zone of growth inhibition (19.3 mm) was given by Drovid on Streptococcus spp., while the smallest (7.0 mm) was by Floxavid on P. aeruginosa. Lysol had the highest mean zone of growth inhibition (18.0 mm) on Streptococcus spp. while P. aeruginosa and Bacillus spp. had no zone of growth inhibition with Roberts at 100-fold dilution. All the isolates were also resistant to Wex-cide. The test organisms were found to be significantly susceptible to the routinely used antimicrobials tested. However, there is the need for continuous surveillance for the detection of emerging resistance pattern.

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

    Science.gov (United States)

    Jonák, J

    2007-04-15

    Prokaryotic elongation factors EF-Tu form a family of homologous, three-domain molecular switches catalyzing the binding of aminoacyl-tRNAs to ribosomes during the process of mRNA translation. They are GTP-binding proteins, or GTPases. Binding of GTP or GDP regulates their conformation and thus their activity. Because of their particular structure and regulation, various activities (also outside of the translation system) and a relative abundance they represent attractive tools for studies of many basic but still not fully understood mechanisms both of the translation process, the structure-function relationships in EF-Tu molecules themselves and proteins and energy transduction mechanisms in general. The review critically summarizes procedures for the isolation and purification of native and engineered eubacterial elongation factors EF-Tu and their mutants on a large as well as small scale. Current protocols for the purification of both native and polyHis-tagged or glutathione-S-transferase (GST)-tagged EF-Tu proteins and their variants using conventional procedures and the Ni-NTA-Agarose or Glutathione Sepharose are presented.

  17. Anaerobic biotransformation of high concentrations of chloroform by an enrichment culture and two bacterial isolates.

    Science.gov (United States)

    Shan, Huifeng; Kurtz, Harry D; Mykytczuk, Nadia; Trevors, Jack T; Freedman, David L

    2010-10-01

    A fermentative enrichment culture (designated DHM-1) was developed that is capable of cometabolically biotransforming high concentrations of chloroform (CF) to nontoxic end products. Two Pantoea spp. were isolated from DHM-1 that also possess this dechlorination capability. Following acclimation to increasing levels of CF, corn syrup-grown DHM-1 was able to transform over 500 mg/liter CF in the presence of vitamin B(12) (approximately 3% of CF on a molar basis) at a rate as high as 22 mg/liter/day in a mineral salts medium. CO, CO(2), and organic acids were the predominant biodegradation products, suggesting that hydrolytic reactions predominate during CF transformation. DHM-1 was capable of growing on corn syrup in the presence of high concentrations of CF (as may be present near contaminant source zones in groundwater), which makes it a promising culture for bioaugmentation. Strains DHM-1B and DHM-1T transform CF at rates similar to that of the DHM-1 enrichment culture. The ability of these strains to grow in the presence of high concentrations of CF appears to be related to alteration of membrane fluidity or homeoviscous and homeophasic adaptation.

  18. Bioelectricity production from microbial fuel cell using mixed bacterial culture isolated from distillery wastewater.

    Science.gov (United States)

    Samsudeen, N; Radhakrishnan, T K; Matheswaran, Manickam

    2015-11-01

    The effect of various system parameters such as wastewater Chemical Oxygen Demand (COD) concentration, pH, conductivity, membrane size and thickness on efficient energy production using mixed isolated culture from the distillery wastewater in the MFC was studied. The power density increased with increase in the anolyte pH from 6 to 8. The peak power density and COD removal efficiency was observed as 63.8±0.65 mW/m(2) and 63.5±1.5% at pH 8, respectively. The MFC performance increased with increasing COD concentration (800-3200 mg/l), conductivity (1.1-9.7 mS/cm) and membrane area (8-24 cm(2)). The MFC operating with wastewater COD concentration of 3200 mg/l and its conductivity of 9.7 mS/cm produced the highest power density of 202±6 mW/m(2) with a corresponding current density of 412±12 mA/m(2). The results showed that the efficient electricity generation and simultaneous treatment of distillery wastewater can be attained in the MFC.

  19. 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.

  20. Anti-bacterial effects of enzymatically-isolated sialic acid from glycomacropeptide in a Helicobacter pylori-infected murine model

    Science.gov (United States)

    Noh, Hye-Ji; Koh, Hong Bum; Kim, Hee-Kyoung; Cho, Hyang Hyun

    2017-01-01

    BACKGROUND/OBJECTIVES Helicobacter pylori (H. pylori) colonization of the stomach mucosa and duodenum is the major cause of acute and chronic gastroduodenal pathology in humans. Efforts to find effective anti-bacterial strategies against H. pylori for the non-antibiotic control of H. pylori infection are urgently required. In this study, we used whey to prepare glycomacropeptide (GMP), from which sialic acid (G-SA) was enzymatically isolated. We investigated the anti-bacterial effects of G-SA against H. pylori in vitro and in an H. pylori-infected murine model. MATERIALS/METHODS The anti-bacterial activity of G-SA was measured in vitro using the macrodilution method, and interleukin-8 (IL-8) production was measured in H. pylori and AGS cell co-cultures by ELISA. For in vivo study, G-SA 5 g/kg body weight (bw)/day and H. pylori were administered to mice three times over one week. After one week, G-SA 5 g/kg bw/day alone was administered every day for one week. Tumor necrosis factor-α (TNF-α), IL-1β, IL-6, and IL-10 levels were measured by ELISA to determine the anti-inflammatory effects of G-SA. In addition, real-time PCR was performed to measure the genetic expression of cytotoxin-associated gene A (cagA). RESULTS G-SA inhibited the growth of H. pylori and suppressed IL-8 production in H. pylori and in AGS cell co-cultures in vitro. In the in vivo assay, administration of G-SA reduced levels of IL-1β and IL-6 pro-inflammatory cytokines whereas IL-10 level increased. Also, G-SA suppressed the expression of cagA in the stomach of H. pylori-infected mice. CONCLUSION G-SA possesses anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect in an experimental H. pylori-infected murine model. G-SA has potential as an alternative to antibiotics for the prevention of H. pylori infection and H. pylori-induced gastric disease prevention. PMID:28194260

  1. Complete genome sequence of the extremely acidophilic methanotroph isolate V4, Methylacidiphilum infernorum, a representative of the bacterial phylum Verrucomicrobia

    Directory of Open Access Journals (Sweden)

    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

  2. Phytochemical Screening and In Vitro Anti-Bacterial Studies of the Ethanolic Extract of Citrus Senensis (Linn.) Peel against some Clinical Bacterial Isolates

    OpenAIRE

    Lawal, D.; J. A. Bala; S. Y. Aliyu; M. A. Huguma

    2013-01-01

    Citrus senensis peel has many medicinal properties and is widely used against various ailments, such as colic, upset stomach, cancer, diuretic, cormunative, immuno – enhancing, stomachic, tonic to digestive system, immune system and skin. It is also used to treat and prevent vitamin deficiencies, colds, flu, and scurvy and helping to fight viral and bacterial infections. The aim of the study is to verify the ethnomedicinal use of the peel as anti-bacterial. The peels were air-dried and ground...

  3. A biogeochemical and genetic survey of acetylene fermentation by environmental samples and bacterial isolates

    Science.gov (United States)

    Miller, Laurence G.; Baesman, Shaun M.; Kirshtein, Julie; Voytek, Mary A.; Oremland, Ronald S.

    2013-01-01

    Anoxic samples (sediment and groundwater) from 13 chemically diverse field sites were assayed for their ability to consume acetylene (C2H2). Over incubation periods ranging from ˜ 10 to 80 days, selected samples from 7 of the 13 tested sites displayed significant C2H2 removal. No significant formation of ethylene was noted in these incubations; therefore, C2H2 consumption could be attributed to acetylene hydratase (AH) rather than nitrogenase activity. This putative AH (PAH) activity was observed in only 21% of the total of assayed samples, while amplification of AH genes from extracted DNA using degenerate primers derived from Pelobacter acetylenicus occurred in even fewer (9.8%) samples. Acetylene-fermenting bacteria were isolated as a pure culture from the sediments of a tidal mudflat in San Francisco Bay (SFB93) and as an enrichment culture from freshwater Searsville Lake (SV7). Comparison of 16S rDNA clone libraries revealed that SFB93 was closely related to P. carbolinicus, while SV7 consisted of several unrelated bacteria. AH gene was amplified from SFB93 but not SV7. The inability of the primers to generate amplicons in the SV7 enrichment, as well as from several of the environmental samples that displayed PAH activity, implied that either the primers were too highly constrained in their specificity or that there was a different type of AH gene in these environmental samples than occurs in P. acetylenicus. The significance of this work with regard to the search for life in the outer Solar System, where C2HL2 is abundant, is discussed.

  4. Pseudomonas syringae pv. actinidiae (PSA isolates from recent bacterial canker of kiwifruit outbreaks belong to the same genetic lineage.

    Directory of Open Access Journals (Sweden)

    Angelo Mazzaglia

    Full Text Available Intercontinental spread of emerging plant diseases is one of the most serious threats to world agriculture. One emerging disease is bacterial canker of kiwi fruit (Actinidia deliciosa and A. chinensis caused by Pseudomonas syringae pv. actinidiae (PSA. The disease first occurred in China and Japan in the 1980s and in Korea and Italy in the 1990s. A more severe form of the disease broke out in Italy in 2008 and in additional countries in 2010 and 2011 threatening the viability of the global kiwi fruit industry. To start investigating the source and routes of international transmission of PSA, genomes of strains from China (the country of origin of the genus Actinidia, Japan, Korea, Italy and Portugal have been sequenced. Strains from China, Italy, and Portugal have been found to belong to the same clonal lineage with only 6 single nucleotide polymorphisms (SNPs in 3,453,192 bp and one genomic island distinguishing the Chinese strains from the European strains. Not more than two SNPs distinguish each of the Italian and Portuguese strains from each other. The Japanese and Korean strains belong to a separate genetic lineage as previously reported. Analysis of additional European isolates and of New Zealand isolates exploiting genome-derived markers showed that these strains belong to the same lineage as the Italian and Chinese strains. Interestingly, the analyzed New Zealand strains are identical to European strains at the tested SNP loci but test positive for the genomic island present in the sequenced Chinese strains and negative for the genomic island present in the European strains. Results are interpreted in regard to the possible direction of movement of the pathogen between countries and suggest a possible Chinese origin of the European and New Zealand outbreaks.

  5. Evaluation of antibacterial efficacy of anise wastes against some multidrug resistant bacterial isolates

    Directory of Open Access Journals (Sweden)

    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

  6. Leisingera sp. JC1, a Bacterial Isolate from Hawaiian Bobtail Squid Eggs, Produces Indigoidine and Differentially Inhibits Vibrios.

    Science.gov (United States)

    Gromek, Samantha M; Suria, Andrea M; Fullmer, Matthew S; Garcia, Jillian L; Gogarten, Johann Peter; Nyholm, Spencer V; Balunas, Marcy J

    2016-01-01

    Female members of many cephalopod species house a bacterial consortium in the accessory nidamental gland (ANG), part of the reproductive system. These bacteria are deposited into eggs that are then laid in the environment where they must develop unprotected from predation, pathogens, and fouling. In this study, we characterized the genome and secondary metabolite production of Leisingera sp. JC1, a member of the roseobacter clade (Rhodobacteraceae) of Alphaproteobacteria isolated from the jelly coat of eggs from the Hawaiian bobtail squid, Euprymna scolopes. Whole genome sequencing and MLSA analysis revealed that Leisingera sp. JC1 falls within a group of roseobacters associated with squid ANGs. Genome and biochemical analyses revealed the potential for and production of a number of secondary metabolites, including siderophores and acyl-homoserine lactones involved with quorum sensing. The complete biosynthetic gene cluster for the pigment indigoidine was detected in the genome and mass spectrometry confirmed the production of this compound. Furthermore, we investigated the production of indigoidine under co-culture conditions with Vibrio fischeri, the light organ symbiont of E. scolopes, and with other vibrios. Finally, both Leisingera sp. JC1 and secondary metabolite extracts of this strain had differential antimicrobial activity against a number of marine vibrios, suggesting that Leisingera sp. JC1 may play a role in host defense against other marine bacteria either in the eggs and/or ANG. These data also suggest that indigoidine may be partially, but not wholly, responsible for the antimicrobial activity of this squid-associated bacterium.

  7. TDtest: easy detection of bacterial tolerance and persistence in clinical isolates by a modified disk-diffusion assay

    Science.gov (United States)

    Gefen, Orit; Chekol, Betty; Strahilevitz, Jacob; Balaban, Nathalie Q.

    2017-01-01

    Antibiotic tolerance - the ability for prolonged survival under bactericidal treatments - is a potentially clinically significant phenomenon that is commonly overlooked in the clinical microbiology laboratory. Recent in vitro experiments show that high tolerance can evolve under intermittent antibiotic treatments in as little as eight exposures to high doses of antibiotics, suggesting that tolerance may evolve also in patients. However, tests for antibiotic susceptibilities, such as the disk-diffusion assay, evaluate only the concentration at which a bacterial strain stops growing, namely resistance level. High tolerance strains will not be detected using these tests. We present a simple modification of the standard disk-diffusion assay that allows the semi-quantitative evaluation of tolerance levels. This novel method, the “TDtest”, enabled the detection of tolerant and persistent bacteria by promoting the growth of the surviving bacteria in the inhibition zone, once the antibiotic has diffused away. Using the TDtest, we were able to detect different levels of antibiotic tolerance in clinical isolates of E. coli. The TDtest also identified antibiotics that effectively eliminate tolerant bacteria. The additional information on drug susceptibility provided by the TDtest should enable tailoring better treatment regimens for pathogenic bacteria. PMID:28145464

  8. A comparative ecotoxicity analysis of α- and γ-phase aluminium oxide nanoparticles towards a freshwater bacterial isolate Bacillus licheniformis.

    Science.gov (United States)

    Pakrashi, Sunandan; Kumar, Deepak; Iswarya, V; Bhuvaneshwari, M; Chandrasekaran, N; Mukherjee, Amitava

    2014-12-01

    Crystalline structure of nanoparticles may influence their physicochemical behaviour as well as their toxicological impact on biota. The differences in orientation of the atoms result in the variations in chemical stability. Thus, toxicological impacts of different crystalline phases of aluminium oxide nanoparticles are expected to vary. The present study brings out a comparative toxicity analysis of γ-phase and α-phase aluminium oxide nanoparticles of comparable hydrodynamic size range towards a freshwater bacterial isolate Bacillus licheniformis at low exposure concentrations (5, 1, 0.5 and 0.05 µg/mL). Upon 2-h exposure, the α-aluminium oxide particles showed lower toxicity than the γ-phase aluminium oxide. The lower level of oxidative stress generation and cell membrane damage in case of the α-phase aluminium oxide nanoparticles substantiated the toxicity results. The involvement of protein, lipopolysaccharides in nanoparticle-cell surface interaction, was noted in both the cases. To conclude, the crystallinity of aluminium oxide nanoparticles played an important role in the interaction and the toxicity response.

  9. 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.

  10. Phytochemical and antibacterial activity of the extracts of Fagara zanthoxyloides on selected cariogenic and enteric bacterial isolates

    Directory of Open Access Journals (Sweden)

    Martins Ajibade Adefisoye

    2012-02-01

    Methods: Crude extracts were obtained by cold extraction method of the powdered stem in methanol-water mixture (MW in ratio 3:2 and phosphate buffer saline (PBS. Filtrates obtained were concentrated in a rotary evaporator and lyophilized. Antimicrobial activity of the extracts, at a concentration of 25 mg/ml was tested against four bacterial isolates using agar well diffusion method. Phytochemical analysis of the plant extract for the presence of tannins, saponins, alkaloids and flavanoids was based on chemical examination. Results and discussions: Extracts from methanol-water mixture showed some antimicrobial activity against Lactobacillus brevis (NCIMB 4617, L. plantarum (NCDO 1752 and Escherichia coli and Proteus vulgaris. The minimum inhibitory concentration (MIC of extracts ranged between 1.57 and 12.5 mg/ml except in E. coli with value greater than 12.5.mg/ml. The phytochemical screening indicated that the extract tested positive for tannin, saponin, flavonoids and alkaloids. Results showed that F. zanthoxyloides would be valuable in the treatment of microbial diseases particularly those of the oral cavity. The considerable antibacterial activities exhibited by the extract of the plant thus justify the use as a teeth cleansing agent in the local setting. The problem of antibiotics resistance to synthetic drugs is also expected to be mitigated with the use of natural drugs. [J Intercult Ethnopharmacol 2012; 1(1.000: 1-6

  11. Degradation of Bacterial Quorum Sensing Signaling Molecules by the Microscopic Yeast Trichosporon loubieri Isolated from Tropical Wetland Waters

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    Cheng-Siang Wong

    2013-09-01

    Full Text Available Proteobacteria produce N-acylhomoserine lactones as signaling molecules, which will bind to their cognate receptor and activate quorum sensing-mediated phenotypes in a population-dependent manner. Although quorum sensing signaling molecules can be degraded by bacteria or fungi, there is no reported work on the degradation of such molecules by basidiomycetous yeast. By using a minimal growth medium containing N-3-oxohexanoylhomoserine lactone as the sole source of carbon, a wetland water sample from Malaysia was enriched for microbial strains that can degrade N-acylhomoserine lactones, and consequently, a basidiomycetous yeast strain WW1C was isolated. Morphological phenotype and molecular analyses confirmed that WW1C was a strain of Trichosporon loubieri. We showed that WW1C degraded AHLs with N-acyl side chains ranging from 4 to 10 carbons in length, with or without oxo group substitutions at the C3 position. Re-lactonisation bioassays revealed that WW1C degraded AHLs via a lactonase activity. To the best of our knowledge, this is the first report of degradation of N-acyl-homoserine lactones and utilization of N-3-oxohexanoylhomoserine as carbon and nitrogen source for growth by basidiomycetous yeast from tropical wetland water; and the degradation of bacterial quorum sensing molecules by an eukaryotic yeast.

  12. Characterization of a Novel Mesophilic Bacterial Amylase Secreted by ZW2531-1,a Strain Newly Isolated from Soil

    Institute of Scientific and Technical Information of China (English)

    WANG Yang; LI Fan; GAO Chao-hui; ZHANG Ying-Jiu

    2009-01-01

    A novel mesophilic bacterial amylase,named oligosaccharide-producing multifunctional amylase(OPMA),was discovered and characterized.OPMA is an extracellular enzyme secreted by ZW2531-1,a strain newly isolated from Chinese soil.It could be purified to homogeneity from the culture supematant of ZW2531-1 by 30%-60% saturated ammonium sulfate precipitation,followed by twice Sephadex gel filtration chromatography.OPMA is a 66 kDa protein based on SDS-PAGE and has an isoelectric point(p/) at pH=5.3 by Isoelectric focusing electrophoresis(IFE),it only catalyzes the degradation of starch,rather than other alpha-1,4-and/or 1,6-glucan polysaccharides such as β-cyclomaltodextrin and pullulan.OPMA degraded starch to produce several oligosccharides including maltose,maltotriose,and isomaltotriose as the major end-products,and perhaps other oligosaccharides such as isomaltotetraose,rather than glucose.OPMA exhibited optimal catalytic activity at a reaction temperature of 50 ℃ and pH=6.0,as determined by orthogonal test.Under the optimal reaction conditions,purified OPMA had a specific activity of 13.75 U/mg.These findings suggest that OPMA could be used for the production of some oligosaccharides beneficial to the food industry and medicine.

  13. Isolation and characterization of bovine herpesvirus 4 (BoHV-4 from a cow affected by post partum metritis and cloning of the genome as a bacterial artificial chromosome

    Directory of Open Access Journals (Sweden)

    Cavirani Sandro

    2009-08-01

    Full Text Available Abstract Background Bovine herpesvirus 4 (BoHV-4 is a gammaherpesvirus with a Worldwide distribution in cattle and is often isolated from the uterus of animals with postpartum metritis or pelvic inflammatory disease. Virus strain adaptation to an organ, tissue or cell type is an important issue for the pathogenesis of disease. To explore the mechanistic role of viral strain variation for uterine disease, the present study aimed to develop a tool enabling precise genetic discrimination between strains of BoHV-4 and to easily manipulate the viral genome. Methods A strain of BoHV-4 was isolated from the uterus of a persistently infected cow and designated BoHV-4-U. The authenticity of the isolate was confirmed by RFLP-PCR and sequencing using the TK and IE2 loci as genetic marker regions for the BoHV-4 genome. The isolated genome was cloned as a Bacterial Artificial Chromosome (BAC and manipulated through recombineering technology Results The BoHV-4-U genome was successfully cloned as a BAC, and the stability of the pBAC-BoHV-4-U clone was confirmed over twenty passages, with viral growth similar to the wild type virus. The feasibility of using BoHV-4-U for mutagenesis was demonstrated using the BAC recombineering system. Conclusion The analysis of genome strain variation is a key method for investigating genes associated with disease. A resource for dissection of the interactions between BoHV-4 and host endometrial cells was generated by cloning the genome of BoHV-4 as a BAC.

  14. Biodegradation of Maya crude oil fractions by bacterial strains and a defined mixed culture isolated from Cyperus laxus rhizosphere soil in a contaminated site

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Ramirez, I. J.; Gutierrez-Rojas, M.; Favela-Torres, E. [Autonomous Metropolitan University (UAM)- Iztapalapa, Dept. of Biotechnology, Federal District (Mexico); Ramirez-Sada, H. [Autonomous Metropolitan University (UAM)-Xochimilco, Dept. of Biological Systems, Federal District (Mexico)

    2003-12-01

    Biodegradation of aliphatic, aromatic, and polar constituents of Maya crude oil by a set of isolated bacterial strains and a defined mixed culture made up with all isolated strains, was evaluated. The bacterial strains were obtained from the rhizosphere of Cyperus laxus, a native plant on a highly hydrocarbon-polluted site. Oxygen uptake rate was used to determine the culture transfer timing during the enrichment culture. Results showed that five of the isolated strains were able to degrade 50 per cent of the aliphatic fractions of Maya crude oil. With the defined mixed culture the level of biodegradation was 47 per cent for aliphatics and 6 per cent of the aromatic-polar mixture. When grown in the presence of total hydrocarbons, the defined mixed culture was able to degrade 40 per cent of the aliphatic fraction and 26 per cent of the aromatic fraction. By combining enrichment cultures with oxygen uptake rate to determine the culture transfer timing during the enrichment cultures allowed the isolation of bacterial strains that are able to degrade specific hydrocarbon fractions at high consumption rates. 28 refs., 4 tabs., 1 fig.

  15. Clinical comparison of isolator, Septi-Chek, nonvented tryptic soy broth, and direct agar plating combined with thioglycolate broth for diagnosing spontaneous bacterial peritonitis.

    Science.gov (United States)

    Hay, J E; Cockerill, F R; Kaese, D; Vetter, E A; Wollan, P C; Rakela, J; Wilhelm, M P

    1996-01-01

    Spontaneous bacterial peritonitis is a life-threatening complication of cirrhotic ascites. Optimal patient management depends on the isolation of the causal organism from ascitic fluid. To evaluate culture techniques for the diagnosis of spontaneous bacterial peritonitis, we prospectively compared three blood culture system, the Isolator system, a lysis-centrifugation system, the Septi-Chek system, a biphasic culture system, and a nonvented tryptic soy broth system, all inoculated at the bedside, and our standard method of direct inoculation of specimens after transport to the laboratory onto agar plates and into thioglycolate broth. The results showed that the Septi-Chek and nonvented tryptic soy broth systems each recovered statistically significantly more pathogens than either the Isolator system (P = 0.0084) or the standard method (P = 0.00098). The Isolator system recovered more pathogens than the standard plate method, but this difference was not statistically significant. Both the Isolator system and the standard plate method recovered more contaminating microorganisms than the Septi-Chek or nonvented tryptic soy broth system. The Isolator system required the most processing time compared with the processing times required by any other method. PMID:8748267

  16. Identification of nif genes in N2-fixing bacterial strains isolated from rice fields along the Yangtze River Plain.

    Science.gov (United States)

    Xie, Guang Hui; Cui, Zongjun; Yu, Jun; Yan, Jing; Hai, Weili; Steinberger, Yosef

    2006-01-01

    The aim of this research was to identify nifH and nifHDKYE ' genes in twenty strains of N2-fixing heterotrophic bacteria isolated from rice fields in the Yangtze River Plain. Southern hybridization of the total DNA from each strain was performed with the Klebsiella pneumoniae nifHDKYE ' gene probe (6.2 kb Eco RI fragment from pSA30) and the Azospirillum brasilense nifH gene probe (0.6 kb Eco RI-Hin dIII fragment from pHU8). We found that Eco RI fragments of total DNA from Aeromonas hydrophila HY2, Bacillus azotoformans FD, Bacillus licheniformis NCH1, NCH5, WH4, Bacillus brevis NC2, Bacillus pumilus NC12, Bacillus cereus NCH2, Citrobacter freundii HY5, HY9, Derxia gummosa HZ5, Pseudomonas mendocina HZ1 and Pseudomonas pseudoalcaligenes WH3 were positively hybridized with both of the probes. Agrobacterium radiobacter HY17, Corynebacterium sp. HY12, YZ and Pseudomonas sp. HY11 had Eco RI fragments hybridized with the K. pneumoniae nifHDKYE ' gene probe. An Eco RI fragment of total DNA from Bacillus megaterium YY4 was positively hybridized to the A. brasilense nifH gene probe. No hybridization sign was found in the total DNA fragments from Alcaligenes cupidus YY6 and Corynebacterium sp. NC11 hybridized with either of the gene probes. The data provide the number and size of EcoRI fragments of the total DNA hybridized with the nif gene probes for these strains of rarely studied species, suggesting additional evidence for N2 fixing and nif gene diversity of N2-fixing bacteria in rice fields along the Yangtze River Plain.

  17. 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.

  18. 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

    2015-09-25

    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.

  19. 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.

  20. The effect of pH and chemical preservatives on the growth of bacterial isolates from some Nigerian packaged fruit juices.

    Science.gov (United States)

    Oladipo, I C; Adeleke, D T; Adebiyi, A O

    2010-01-01

    Bacterial pathogens were isolated from some Nigerian packaged fruit juices. The isolates were characterized and identified as Bacillus licheniformis, Aeromonas hydrophila, Bacillus circulans, Proteus morganii, Pseudomonas cepacia, Bacillus alvei and Pseudomonas chlororaphis. The antibiotic susceptibility profile of the seven isolates was determined and it was discovered that 65% of the microorganisms isolated were resistance to the antibiotic used while 35% were sensitive. The effect of pH, benzoic acid and sodium chloride concentration on the growth rate of isolates was investigated. It was found that as the pH of the growth medium increased from 3 to 9, the rate of growth of most isolates also increased except for Pseudomonas cepacia, which had optimum growth at neutral pH 7. As the concentration of sodium chloride increased from 2 to 5%, the rate of growth of all the seven isolates decreased. It was also noted that as concentration of benzoic acid increased from 250 to 1000 mg L(-1) Bacillus licheniformis decreased from 1.330 to 0.167 nm, Aeromonas hydrophila decreased from 1.208 to 0.164 nm Bacillus circulans decreases from 1.158 to 0.299 nm, Proteus morganii decreases from 1.377 to 0.141 nm etc. The higher the concentration of Benzoic acid the lower the rate of growth of the isolates.

  1. Antibacterial and antibiotic potentiating activity of Vangueria madagascariensis leaves and ripe fruit pericarp against human pathogenic clinical bacterial isolates

    Directory of Open Access Journals (Sweden)

    M. Fawzi Mahomoodally

    2016-10-01

    Full Text Available This study aimed to assess the antibacterial and antibiotic potentiating property of Vangueria madagascariensis (VM (fruit and leaf extracts against 10 clinical isolates. A microdilution broth susceptibility assay for bacteria was used for the determination of the minimum inhibitory concentration (MIC and associated with antibiotics to evaluate any synergistic effect. VM extracts were found to potentiate the activity of 3 conventional antibiotics. Chloramphenicol and Ciprofloxacin showed no activity against Acinetobacter spp. but when mixed with VM (in a ratio of 50% VM extracts: 30% antibiotic, showed potentiating effect. The methanolic fruit extract at lower concentration of Chloramphenicol (30% gave better synergistic effect (MIC = 3.75 μg/mL as compared to 50% (MIC = 12.5 μg/mL. With Gentamicin, no activity was detected with leaf decoction but other extracts (methanolic leaf/fruit extract and fruit decoction showed enhancement (MIC- 0.47, 7.5 and 15 μg/mL respectively. Interestingly, Chloramphenicol showed no activity against MRSA, but when mixed with VM, produced low MICs (<0.39–0.78 μg/mL with 50% antibiotic and from <0.47 to 0.94 μg/mL with 30% antibiotic. Combining Gentamicin with VM extracts showed an enhancement in the potentiating activity against MRSA. In conclusion, the observed antimicrobial property of VM tend to suggest a promising alternative and complementary strategy to manage bacterial infections and hence can open new avenues for further research using traditional medicinal food plant.

  2. Antibacterial and antibiotic potentiating activity of Vangueria madagascariensis leaves and ripe fruit pericarp against human pathogenic clinical bacterial isolates.

    Science.gov (United States)

    Mahomoodally, M Fawzi; Dilmohamed, Schajeed

    2016-10-01

    This study aimed to assess the antibacterial and antibiotic potentiating property of Vangueria madagascariensis (VM) (fruit and leaf extracts) against 10 clinical isolates. A microdilution broth susceptibility assay for bacteria was used for the determination of the minimum inhibitory concentration (MIC) and associated with antibiotics to evaluate any synergistic effect. VM extracts were found to potentiate the activity of 3 conventional antibiotics. Chloramphenicol and Ciprofloxacin showed no activity against Acinetobacter spp. but when mixed with VM (in a ratio of 50% VM extracts: 30% antibiotic), showed potentiating effect. The methanolic fruit extract at lower concentration of Chloramphenicol (30%) gave better synergistic effect (MIC = 3.75 μg/mL) as compared to 50% (MIC = 12.5 μg/mL). With Gentamicin, no activity was detected with leaf decoction but other extracts (methanolic leaf/fruit extract and fruit decoction) showed enhancement (MIC- 0.47, 7.5 and 15 μg/mL respectively). Interestingly, Chloramphenicol showed no activity against MRSA, but when mixed with VM, produced low MICs (<0.39-0.78 μg/mL with 50% antibiotic and from <0.47 to 0.94 μg/mL with 30% antibiotic). Combining Gentamicin with VM extracts showed an enhancement in the potentiating activity against MRSA. In conclusion, the observed antimicrobial property of VM tend to suggest a promising alternative and complementary strategy to manage bacterial infections and hence can open new avenues for further research using traditional medicinal food plant.

  3. Leisingera sp. JC1, a Bacterial Isolate from Hawaiian Bobtail Squid Eggs, Produces Indigoidine and Differentially Inhibits Vibrios

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    Samantha M. Gromek

    2016-09-01

    Full Text Available Female members of many cephalopod species house a bacterial consortium that is part of their reproductive system, the accessory nidamental gland (ANG. These bacteria are deposited into eggs that are then laid in the environment where they must develop unprotected from predation, pathogens and fouling. In this study, we characterized the genome and secondary metabolite production of Leisingera sp. JC1, a member of the roseobacter clade (Rhodobacteraceae of Alphaproteobacteria isolated from the jelly coat of eggs from the Hawaiian bobtail squid, Euprymna scolopes. Whole genome sequencing and MLSA analysis revealed that Leisingera sp. JC1 falls within a group of roseobacters associated with squid ANGs. Genome and biochemical analyses revealed the potential for and production of a number of secondary metabolites, including siderophores and acyl-homoserine lactones involved with quorum sensing. The complete biosynthetic gene cluster for the pigment indigoidine was detected in the genome and mass spectrometry confirmed the production of this compound. Furthermore, we investigated the production of indigoidine under co-culture conditions with Vibrio fischeri, the light organ symbiont of E. scolopes, and with other vibrios. Finally, both Leisingera sp. JC1 and secondary metabolite extracts of this strain had differential antimicrobial activity against a number of marine vibrios, suggesting that Leisingera sp. JC1 may play a role in host defense against other marine bacteria either in the eggs and/or ANG. These data also suggest that indigoidine may be partially, but not wholly, responsible for the antimicrobial activity of this squid-associated bacterium. □

  4. 405 nm light exposure of osteoblasts and inactivation of bacterial isolates from arthroplasty patients: potential for new disinfection applications?

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    RS McDonald

    2013-01-01

    Full Text Available Infection rates after arthroplasty surgery are between 1-4 %, rising significantly after revision procedures. To reduce the associated costs of treating these infections, and the patients’ post-operative discomfort and trauma, a new preventative method is required. High intensity narrow spectrum (HINS 405 nm light has bactericidal effects on a wide range of medically important bacteria, and it reduced bacterial bioburden when used as an environmental disinfection method in a Medical Burns Unit. To prove its safety for use for environmental disinfection in orthopaedic theatres during surgery, cultured osteoblasts were exposed to HINS-light of intensities up to 15 mW/cm2 for 1 h (54 J/cm2. Intensities of up to 5 mW/cm2 for 1 h had no effect on cell morphology, activity of alkaline phosphatase, synthesis of collagen or osteocalcin expression, demonstrating that under these conditions this dose is the maximum safe exposure for osteoblasts; after exposure to 15 mW/cm2 all parameters of osteoblast function were significantly decreased. Viability (measured by protein content and Crystal Violet staining of the osteoblasts was not influenced by exposure to 5 mW/cm2 for at least 2 h. At 5 mW/cm2 HINS-light is an effective bactericide. It killed 98.1 % of Staphylococcus aureus and 83.2 % Staphylococcus epidermis populations seeded on agar surfaces, and is active against both laboratory strains and clinical isolates from infected hip and knee arthroplasties. HINS-light could have potential for development as a method of disinfection to reduce transmission of bacteria during arthroplasty, with wider applications in diverse surgical procedures involving implantation of a medical device.

  5. Common causes of vaginal infections and antibiotic susceptibility of aerobic bacterial isolates in women of reproductive age attending at Felegehiwot Referral Hospital, Ethiopia: a cross sectional study.

    Science.gov (United States)

    Mulu, Wondemagegn; Yimer, Mulat; Zenebe, Yohannes; Abera, Bayeh

    2015-05-13

    Bacterial vaginosis, candidal, trichomonal and Gonococcal vaginal infections are a major health problems associated with gynecologic complications and increase in replication, shedding and transmission of HIV and other STIs in women of reproductive age. The study aimed at determining the prevalence of common vaginal infections and antimicrobial susceptibility profiles of aerobic bacterial isolates in women of reproductive age, attending Felegehiwot referral Hospital. A hospital based cross sectional study was conducted from May to November, 2013. Simple random sampling technique was used. Demographic variables were collected using a structured questionnaire. Clinical data were collected by physicians. Two vaginal swab specimens were collected from each participant. Wet mount and Gram staining were carried out to identify motile T.vaginalis, budding yeast and clue cells. All vaginal specimens were cultured for aerobic bacterial isolates using standard microbiology methods. Antimicrobial susceptibility was performed using disc diffusion technique as per the standard by Kirby-Bauer method. The results were analyzed using descriptive, chi-square and fisher's exact test as appropriate. A total of 409 women in reproductive age (15 - 49 years) participated in the study. The median age of the women was 28 years. Overall, 63 (15.4 %) of women had vaginal infections. The proportion of vaginal infection was higher in non-pregnant (17.3 %) than pregnant women (13.3 %) (P = 0.002). The most common identified vaginal infections were candidiasis (8.3 %) and bacterial vaginosis (2.8 %) followed by trichomoniasis (2.1 %). The isolation rate of N. gonorrhoeae and group B Streptococcus colonization was 4 (1 %) and 6 (1.2 %), respectively. Bacterial vaginosis was higher in non-pregnant (5.6 %) than pregnant women (0.5 %) (P = 0.002). Religion, age, living in rural area and having lower abdominal pain were significantly associated with bacterial vaginosis and

  6. A Year of Infection in the Intensive Care Unit: Prospective Whole Genome Sequencing of Bacterial Clinical Isolates Reveals Cryptic Transmissions and Novel Microbiota.

    Science.gov (United States)

    Roach, David J; Burton, Joshua N; Lee, Choli; Stackhouse, Bethany; Butler-Wu, Susan M; Cookson, Brad T; Shendure, Jay; Salipante, Stephen J

    2015-07-01

    Bacterial whole genome sequencing holds promise as a disruptive technology in clinical microbiology, but it has not yet been applied systematically or comprehensively within a clinical context. Here, over the course of one year, we performed prospective collection and whole genome sequencing of nearly all bacterial isolates obtained from a tertiary care hospital's intensive care units (ICUs). This unbiased collection of 1,229 bacterial genomes from 391 patients enables detailed exploration of several features of clinical pathogens. A sizable fraction of isolates identified as clinically relevant corresponded to previously undescribed species: 12% of isolates assigned a species-level classification by conventional methods actually qualified as distinct, novel genomospecies on the basis of genomic similarity. Pan-genome analysis of the most frequently encountered pathogens in the collection revealed substantial variation in pan-genome size (1,420 to 20,432 genes) and the rate of gene discovery (1 to 152 genes per isolate sequenced). Surprisingly, although potential nosocomial transmission of actively surveilled pathogens was rare, 8.7% of isolates belonged to genomically related clonal lineages that were present among multiple patients, usually with overlapping hospital admissions, and were associated with clinically significant infection in 62% of patients from which they were recovered. Multi-patient clonal lineages were particularly evident in the neonatal care unit, where seven separate Staphylococcus epidermidis clonal lineages were identified, including one lineage associated with bacteremia in 5/9 neonates. Our study highlights key differences in the information made available by conventional microbiological practices versus whole genome sequencing, and motivates the further integration of microbial genome sequencing into routine clinical care.

  7. Isolation and identification of bioactive compounds responsible for the anti-bacterial efficacy of Lotus corniculatus var. São Gabriel

    Directory of Open Access Journals (Sweden)

    Dalmarco Juliana

    2010-01-01

    Full Text Available Lotus corniculatus (Fabaceae is considered a forage plant utilized as food for ruminants in the south of Brazil. This herb is also actually used to treat intestinal infection in these animals. In our experiments, we evaluated the anti-bacterial activity of crude extract from L. corniculatus var. Sγo Gabriel were assayed against Gram-positive and Gram-negative bacterium. The crude extracted did not show any anti-bacterial activity, but the hexane fraction did on Bacillus cereus (MIC=100 μg/mL and on Enterococcus faecalis, Listeria monocytogenes, Staphylococcus aureus, Staphylococcus epidermidis, Acinetobacter calcoaceticus, and Providencia alcalifaciens (MIC=600, 800 or 1000 μg/mL. The Ethyl acetate fraction (AcOEt also showed important anti-bacterial activity on Bacillus cereus, E. faecalis, and Acinetobacter calcoaceticus (MIC=800 μg/mL. The oleanolic acid isolated from hexane fraction showed the same effect on Staphylococcus aureus methycillin-resistant (MIC=100 μg/mL, L. monocytogenes (MIC=25 μg/mL, and Bacillus cereus (MIC=25 μg/mL. Further, Kaempferitrin isolated from ethyl acetate fraction has also shown anti-bacterial activity on Shighella flexinerii (MIC=100 μg/mL, Salmonella typhimurium (MIC=100 μg/mL, A. calcoaceticus (MIC=100 μg/mL, E. faecalis (MIC=3.9 μg/mL, and Bacillus cereus (MIC=8.5 μg/mL. This study suggests that L. corniculatus var. Sγo Gabriel have potential pharmacological property for a new anti-bacterial drug development.

  8. Isolation of high-salinity-tolerant bacterial strains, Enterobacter sp., Serratia sp., Yersinia sp., for nitrification and aerobic denitrification under cyanogenic conditions.

    Science.gov (United States)

    Mpongwana, N; Ntwampe, S K O; Mekuto, L; Akinpelu, E A; Dyantyi, S; Mpentshu, Y

    2016-01-01

    Cyanides (CN(-)) and soluble salts could potentially inhibit biological processes in wastewater treatment plants (WWTPs), such as nitrification and denitrification. Cyanide in wastewater can alter metabolic functions of microbial populations in WWTPs, thus significantly inhibiting nitrifier and denitrifier metabolic processes, rendering the water treatment processes ineffective. In this study, bacterial isolates that are tolerant to high salinity conditions, which are capable of nitrification and aerobic denitrification under cyanogenic conditions, were isolated from a poultry slaughterhouse effluent. Three of the bacterial isolates were found to be able to oxidise NH(4)-N in the presence of 65.91 mg/L of free cyanide (CN(-)) under saline conditions, i.e. 4.5% (w/v) NaCl. The isolates I, H and G, were identified as Enterobacter sp., Yersinia sp. and Serratia sp., respectively. Results showed that 81% (I), 71% (G) and 75% (H) of 400 mg/L NH(4)-N was biodegraded (nitrification) within 72 h, with the rates of biodegradation being suitably described by first order reactions, with rate constants being: 4.19 h(-1) (I), 4.21 h(-1) (H) and 3.79 h(-1) (G), respectively, with correlation coefficients ranging between 0.82 and 0.89. Chemical oxygen demand (COD) removal rates were 38% (I), 42% (H) and 48% (G), over a period of 168 h with COD reduction being highest at near neutral pH.

  9. Biodecolorization of Reactive Black-5 by a metal and salt tolerant bacterial strain Pseudomonas sp. RA20 isolated from Paharang drain effluents in Pakistan.

    Science.gov (United States)

    Hussain, Sabir; Maqbool, Zahid; Ali, Shafaqat; Yasmeen, Tahira; Imran, Muhammad; Mahmood, Faisal; Abbas, Farhat

    2013-12-01

    Discharge of untreated azo dyes contaminated textile wastewater into soil and water bodies causes severe contamination. The present study was conducted to isolate dye degrading bacterial strains from a textile industry wastewater carrying drain in the neighborhood of Faisalabad, Pakistan. Seventy six bacterial strains were initially isolated and was screened using liquid mineral salts medium spiked with Reactive Black-5 azo dye. The strain RA20 was found to be the most efficient azo dye degrading bacterial isolate and was identified by amplifying and sequencing its 16S rRNA. Analysis indicated that this strain belonged to genus Pseudomonas and was designated as Pseudomonas sp. RA20. It had the highest decolorization activity at pH 8 and 25 °C incubation temperature under static conditions using yeast extract as an additional C source. This strain was also effective in decolorizing structurally related other reactive dyes including Reactive Orange 16, Reactive Yellow 2 and Reactive Red 120 but with varying efficacy. RA20 decolorized Reactive Black-5 significantly in the presence of up to 30 g L⁻¹ NaCl; however, the decolorization rate was significantly (p≤0.05) reduced beyond this salt concentration. Moreover, this bacterial strain also exhibited moderate tolerance to different heavy metals including zinc (Zn), cadmium (Cd), chromium (Cr), lead (Pb) and copper (Cu). RA20 also decolorized Reactive Black-5 in the presence of a mixture of the selected heavy metals depending upon their concentrations. This study highlights the importance of Pseudomonas sp. RA20 as a prospective biological resource for bioremediation of water and soils contaminated with azo dyes.

  10. 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

  11. Edwardsiella tarda and Aeromonas hydrophila isolated from diseased Southern flounder (Paralichthys lethostigma) are virulent to channel catfish and Nile tilapia

    Science.gov (United States)

    The aim of this study is to identify bacterial pathogens isolated from diseased Southern flounder and determine their virulence to channel catfish and Nile tilapia. Twenty five Gram-negative bacteria isolates were recovered from five tissues (skin lesions, brain, liver, intestine, and posterior kidn...

  12. 树鼩粪便细菌分离培养与鉴定%Isolation, culture and identification of bacterial strains from tree shrews feces

    Institute of Scientific and Technical Information of China (English)

    刘丽君; 余柄廷; 胡凝珠; 孙晓梅; 王玮; 孙静; 胡云章; 李建芳

    2015-01-01

    Objective Study the fecal flora diversity of the tree shrew , to provide a basis data of fecal bacteria of feeding the tree shrew .Methods Ten tree shrews were used in this study .The Stools of the animals were respectively cultured with oxygen and without oxygen to isolate the bacterial .Then the PCR-amplified 16S rRNA of the bacterial was sequenced and analyzed .Results 25 bacterial strains belonging to ten bacterial species were isolated by anaerobic incubation , and 25 bacterial strains belonging to twelve bacterial species were isolated by aerobic incubation .Proteus vulgaris, Enterococcus faecalis, Escherichia fergusonii, Enterococcus faecium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus , Aeromonas salmonicida subsp .masoucida , Rahnella aquatilis , Exiguobacterium aquaticum , Raoultella terrigena , and Escherichia coli were identified in this study .Conclusions There is a fecal flora diversity of the tree shrew, and the Proteus vulgaris , Escherichia fergusonii and Enterococcus faecium may be the major parasitic flora .%目的:了解人工饲养树鼩粪便菌群多样性,为树鼩的正常饲养繁殖和微生物质量控制标准化提供依据。方法随机采集10份树鼩粪便样品,利用有氧及厌氧培养基进行细菌分离培养,提取细菌基因组DNA后PCR扩增16SrRNA基因并测序鉴定。结果本实验从树鼩粪便样品中,经有氧培养分离鉴定出25株、12种细菌,经厌氧培养分离鉴定出25株、10种细菌,包括变形杆菌属、肠球菌属、埃希菌属、志贺菌属、葡萄球菌属、气单胞菌属、拉恩氏菌属、拉乌尔菌属、微小杆菌属、链球菌属、明串珠菌属。结论树鼩肠道好氧菌及厌氧菌具有丰富的种属多样性,普通变形杆菌群、费格森埃希菌群和屎肠球菌群可能是树鼩肠道的主要寄生菌群。

  13. Workshop on the Application of Genomic Tools for the Rapid Molecular Characterization of Bacterial Isolates in Food-borne Disease Outbreak Investigations Ottawa, ON, February 24-25, 2014

    Science.gov (United States)

    2014-05-01

    pathogens by WGS is leading to a shift in paradigm. At the CDC, WGS began with the investigation of the Haiti cholera outbreak in 2010. The CDC is...Workshop on the Application of Genomic Tools for the Rapid Molecular Characterization of Bacterial Isolates in Food-borne Disease Outbreak ...Characterization of Bacterial Isolates in Food-borne Disease Outbreak Investigations Ottawa, ON, February 24-25, 2014

  14. Twenty Years of KSHV

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    Yuan Chang

    2014-11-01

    Full Text Available Twenty years ago, Kaposi’s sarcoma (KS was the oncologic counterpart to Winston Churchill’s Russia: a riddle, wrapped in a mystery, inside an enigma. First described by Moritz Kaposi in 1872, who reported it to be an aggressive skin tumor, KS became known over the next century as a slow-growing tumor of elderly men—in fact, most KS patients were expected to die with the tumor rather than from it. Nevertheless, the course and manifestations of the disease varied widely in different clinical contexts. The puzzle of KS came to the forefront as a harbinger of the AIDS epidemic. The articles in this issue of Viruses recount progress made in understanding Kaposi’s sarcoma herpesvirus (KSHV since its initial description in 1994.

  15. Fabrication of a platform to isolate the influences of surface nanotopography from chemistry on bacterial attachment and growth.

    Science.gov (United States)

    Pegalajar-Jurado, Adoracion; Easton, Christopher D; Crawford, Russell J; McArthur, Sally L

    2015-03-26

    Billions of dollars are spent annually worldwide to combat the adverse effects of bacterial attachment and biofilm formation in industries as varied as maritime, food, and health. While advances in the fabrication of antifouling surfaces have been reported recently, a number of the essential aspects responsible for the formation of biofilms remain unresolved, including the important initial stages of bacterial attachment to a substrate surface. The reduction of bacterial attachment to surfaces is a key concept in the prevention or minimization of biofilm formation. The chemical and physical characteristics of both the substrate and bacteria are important in understanding the attachment process, but substrate modification is likely the most practical route to enable the extent of bacterial attachment taking place to be effectively controlled. The microtopography and chemistry of the surface are known to influence bacterial attachment. The role of surface chemistry versus nanotopography and their interplay, however, remain unclear. Most methods used for imparting nanotopographical patterns onto a surface also induce changes in the surface chemistry and vice versa. In this study, the authors combine colloidal lithography and plasma polymerization to fabricate homogeneous, reproducible, and periodic nanotopographies with a controllable surface chemistry. The attachment of Escherichia coli bacteria onto carboxyl (plasma polymerized acrylic acid, ppAAc) and hydrocarbon (plasma polymerized octadiene, ppOct) rich plasma polymer films on either flat or colloidal array surfaces revealed that the surface chemistry plays a critical role in bacterial attachment, whereas the effect of surface nanotopography on the bacterial attachment appears to be more difficult to define. This platform represents a promising approach to allow a greater understanding of the role that surface chemistry and nanotopography play on bacterial attachment and the subsequent biofouling of the surface.

  16. Biodegradation of Alachlor in Liquid and Soil Cultures Under Variable Carbon and Nitrogen Sources by Bacterial Consortium Isolated from Corn Field Soil

    Directory of Open Access Journals (Sweden)

    Simin Nasseri

    2013-03-01

    Full Text Available Alachlor, an aniline herbicide widely used in corn production, is frequently detected in water resources. The main objectives of this research were focused on isolating bacterial consortium capable of alachlor biodegradation, assessing the effects of carbon and nitrogen sources on alachlor biodegradation and evaluating the feasibility of using bacterial consortium in soil culture. Kavar corn field soil with a long history of alachlor application in Fars province of Iran has been explored for their potential of alachlor biodegradation. The influence of different carbon compounds (glucose, sodium citrate, sucrose, starch and the combination of these compounds, the effect of nitrogen sources (ammonium nitrate and urea and different pH (5.5-8.5 on alachlor removal efficiency by the bacterial consortium in liquid culture were investigated. After a multi-step enrichment program 100 days of acclimation, a culture with the high capability of alachlor degradation was obtained (63%. Glucose and sodium citrate had the highest alachlor reduction rate (85%. Alachlor reduction rate increased more rapidly by the addition of ammonium nitrate (94% compare to urea. Based on the data obtained in the present study, pH of 7.5 is optimal for alachlor biodegradation. After 30 days of incubation, the percent of alachlor reduction were significantly enhanced in the inoculated soils (74% as compared to uninoculated control soils (17.67% at the soil moisture content of 25%. In conclusion, bioaugmentation of soil with bacterial consortium may enhance the rate of alachlor degradation in a polluted soil.

  17. 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.

  18. Isolation and Identification of a New Tetrodotoxin-Producing Bacterial Species, Raoultella terrigena, from Hong Kong Marine Puffer Fish Takifugu niphobles

    Directory of Open Access Journals (Sweden)

    Fred Wang-Fat Lee

    2011-11-01

    Full Text Available Puffer fish, Takifugu niphobles, collected from the Hong Kong coastal waters were screened for tetrodotoxin-producing bacteria. A Gram-negative, non-acid-fast, non-sporing and rod shaped bacterial strain (designated as gutB01 was isolated from the intestine of the puffer fish and was shown to produce tetrodotoxin (TTX. Based on the Microbial Identification (MIDI and 16S-23S rDNA internal transcribed spacer (ITS phylogenetic analysis, the strain was identified as Raoultella terrigena. The TTX production ability of the strain was confirmed by mouse bioassay, ELISA and mass spectrometry (MALDI-TOF. Our results reiterate that the TTX found in puffer fish was likely produced by the associated bacteria and TTX are widely produced amongst a diversity of bacterial species.

  19. Isolation and identification of a new tetrodotoxin-producing bacterial species, Raoultella terrigena, from Hong Kong marine puffer fish Takifugu niphobles.

    Science.gov (United States)

    Yu, Vincent Chung-Him; Yu, Peter Hoi-Fu; Ho, Kin-Chung; Lee, Fred Wang-Fat

    2011-01-01

    Puffer fish, Takifugu niphobles, collected from the Hong Kong coastal waters were screened for tetrodotoxin-producing bacteria. A Gram-negative, non-acid-fast, non-sporing and rod shaped bacterial strain (designated as gutB01) was isolated from the intestine of the puffer fish and was shown to produce tetrodotoxin (TTX). Based on the Microbial Identification (MIDI) and 16S-23S rDNA internal transcribed spacer (ITS) phylogenetic analysis, the strain was identified as Raoultella terrigena. The TTX production ability of the strain was confirmed by mouse bioassay, ELISA and mass spectrometry (MALDI-TOF). Our results reiterate that the TTX found in puffer fish was likely produced by the associated bacteria and TTX are widely produced amongst a diversity of bacterial species.

  20. Identification of non-Listeria spp. bacterial isolates yielding a β-D-glucosidase-positive phenotype on Agar Listeria according to Ottaviani and Agosti (ALOA).

    Science.gov (United States)

    Angelidis, Apostolos S; Kalamaki, Mary S; Georgiadou, Sofia S

    2015-01-16

    Agar Listeria according to Ottaviani and Agosti (ALOA) is the mandatory medium used for the detection and enumeration of Listeria monocytogenes in foods according to the official International Organization for Standardization (ISO) methods. On ALOA, Listeria spp. appear as bluish-green colonies due to the production of β-D-glucosidase, an enzyme that cleaves 5-bromo-4-chloro-3-indolyl-β-D-glucopyranoside, a chromogenic substrate included in the formulation of the medium. The present work reports on bacterial isolates (n=64) from ready-to-eat soft cheeses, which are able to grow on ALOA, forming bluish-green colonies and therefore phenotypically resemble Listeria spp. All isolates were also capable of growing on the selective media PALCAM and RAPID L'mono. The isolates were characterised with biochemical tests including those specified in the ISO standards for the confirmation of Listeria spp. and identified via partial sequencing of their 16S rRNA gene. According to sequencing results the isolates represented 12 different bacterial species or species-groups belonging to seven different genera: Bacillus spp. (B. circulans, B. clausii, B. licheniformis and B. oleronius), Cellulosimicrobium spp. (C. funkei), Enterococcus spp. (E. faecalis, E. faecium/durans), Kocuria spp. (K. kristinae), Marinilactibacillus spp. (M. psychrotolerans), Rothia spp. (R. terrae) and Staphylococcus spp. (S. sciuri and S. saprophyticus subsp. saprophyticus/xylosus). Cellulosimicrobium spp. have never been previously isolated from foods. These results significantly extend the list of bacteria previously known as capable of growing on ALOA as bluish-green colonies and suggest that there may be room for further improvement in the medium's inhibitory properties towards non-Listeria spp., Gram-positive bacteria present in foods.

  1. Top at Twenty

    CERN Document Server

    2015-01-01

    The "Top at Twenty" workshop is dedicated to the celebration of 20 years since the top quark discovery at Fermilab in 1995. Speakers from all experiments capable of studying top quark, ATLAS, CDF, CMS and DZero, will present the most recent results of the top quark studies based on Run II of the Tevatron and Run I of the LHC. Reviews of such fundamental measurements as mass of the top quark, its spin, charge and production properties are planned with some of them orders of magnitude better in precision in comparison with original CDF and DZero papers announcing the top quark discovery. Measurements of top quark production and decay that illuminate the nature of the Higgs boson and seek new phenomena will be presented. Theoretical talks on how the top quark fits into the Standard Model and its potential extensions will also be presented. This workshop will complement the yearly Top Workshop which is held in September and will benefit from many new results expected to be presented at winter conferences in 2015...

  2. Evaluation of anti–bacterial and anti–oxidant potential of andrographolide and echiodinin isolated from callus culture of Andrographis paniculata Nees

    OpenAIRE

    Mohmmed Arifullah; Nima Dandu Namsa; Manabendra Mandal; Kishore Kumar Chiruvella; Paritala Vikrama; Ghanta Rama Gopal

    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 antioxidant 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 eff...

  3. Isolation and characterisation of bacterial colonies from seeds and in vitro cultures of Fraxinus spp. from Italian sites.

    Science.gov (United States)

    Donnarumma, F; Capuana, M; Vettori, C; Petrini, G; Giannini, R; Indorato, C; Mastromei, G

    2011-01-01

    Culturable bacteria were isolated from seeds, embryos and contaminated in vitro cultures of ash (Fraxinus excelsior L., F. ornus L. and F. angustifolia L.) and were identified using morphological and molecular analyses. Fourteen morphologically distinct isolates were recovered from seeds of Fraxinus spp. 16S rDNA sequencing categorised these isolates into ten separate genera. Three strains isolated from contaminated in vitro cultures, Pantoea agglomerans, Staphylococcus succinus and Aerococcus viridans, were used for comparative analysis with isolates from seeds. Antibiotic sensitivity testing of the isolated contaminants, including phytotoxicity of antibiotics on in vitro cultures of ash, was also investigated. Phytotoxic effects on explants immersed in ampicillin or cultured on medium containing ampicillin were negligible, however tetracycline, either alone or in combination with other antibiotics, had phytotoxic effects. We conclude that ampicillin is a suitable antibiotic to limit the growth of contaminating bacteria during the in vitro culture of ash. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. 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.

  5. 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 ...

  6. Multiple-stress tolerance of ionizing radiation-resistant bacterial isolates obtained from various habitats: correlation between stresses.

    Science.gov (United States)

    Shukla, Manish; Chaturvedi, Ruchi; Tamhane, Dhruti; Vyas, Pranav; Archana, G; Apte, Shree; Bandekar, J; Desai, Anjana

    2007-02-01

    Isolation of five ionizing radiation (IR)-resistant bacteria by screening of isolates from various habitats classified as common and stressed is reported. IR-resistant isolates exhibited varying degrees of resistance to gamma-radiation and were classified as highly and moderately radiation resistant. Resistance to ultraviolet (UV) radiation correlated well with gamma-radiation resistance, whereas a comparable desiccation resistance for all the highly and moderately radiation-resistant isolates was observed. However, salt tolerance failed to correlate with IR resistance, indicating a divergent evolution of the salt tolerance and radiation resistance. Characterization of isolates by the amplified rDNA restriction analysis profiling attested to the clustering of these isolates with their stress phenotype. 16S rRNA gene-based analysis of the isolates showed that the bacteria with similar-resistance physiologies clustered together and belonged to related genera. Hydrogen peroxide resistance and mitomycin survival patterns of the isolates indicated the roles of oxidative-stress tolerance in desiccation survival and recombination repair in higher radiation resistance, respectively.

  7. Occurrence of Potential Bacterial Pathogens and Their Antimicrobial Susceptibility Patterns Isolated from Herbal Medicinal Products Sold in Different Markets of Gondar Town, Northwest Ethiopia

    Directory of Open Access Journals (Sweden)

    Abdela Yesuf

    2016-01-01

    Full Text Available Background. The World Health Organization estimates that about 80% of the world’s population uses herbal medicine to treat various illnesses as means of primary healthcare. However, during preparation, herbal plants may be exposed to contamination by potential pathogens, and this may lead to infections. The aim of this study was to determine bacterial contamination of herbal medicinal products and to assess the antibiotic susceptibility pattern of the isolated bacteria. Methods. A cross-sectional study was conducted from January 1 to May 25, 2013, at Gondar Town. A total of 55 samples used as oral, local, and intranasal routes of administration were collected from the herbalists. Results. In the present study the total aerobic bacterial count ranges from zero to 2.41×109 CFU/g with mean count of 1.99×108 CFU/g or mL while the total coliform count showed an average of 1.05×108 CFU/g or mL with a range of zero to 2.1×109 CFU/g. The most common bacteria isolated were Bacillus spp. followed by Enterobacter spp., Shigella dysenteriae, and Salmonella spp. Multiple drug resistance was not uncommon and it was found that 125 (83.4% of the isolates were resistant to two or more antibiotics. Conclusion. Herbal medicinal preparations were highly contaminated with pathogenic microorganisms with high microbial load. Most of the isolates have multiple drug resistance. Using those contaminated herbal medicines may lead to infection of other health related risks. Therefore, this warrants urgent training of herbalists and management scale-up for quality and safety of medicinal plants.

  8. Antibiotic resistance pattern of bacterial isolates from cases of urinary tract infections among hospitalized and out-patients at a tertiary health facility in South Western Nigeria

    Directory of Open Access Journals (Sweden)

    Oyekale Oluwalana Timothy

    2014-01-01

    Full Text Available Aim: Urinary tract infections (UTIs are among the most common human infections with distribution of causative agents and their susceptibility pattern to antibiotics varying from region to region. This study aimed at determining the bacterial uropathogens and their antibiotic resistance profile among patients in a Nigerian tertiary health care facility. Materials and Methods: Appropriate urine specimens (midstream/catheter specimen urine of all suspected cases of UTI by clinicians were processed in the medical microbiology laboratory for detection of significant bacteriuria. Bacteria uropathogens isolated were identified by standard biochemical tests and antibiotic susceptibility test to eight antibiotics was carried out on them using Kirby-Bauer disc diffusion technique. Methicillin-resistant Staphylococcus aureus (MRSA was identified by cefoxitin disc diffusion technique and extended-spectrum beta-lactamase (ESBL producing enterobacteria were detected using double-disc synergy test. Results: Of the total 157 males and 189 females investigated, 35.7% and 66.1% respectively had significant bacteriuria. Escherichia coli was the most commonly isolated bacterial pathogen both among in- and out-patients (52.6% vs. 65.5%. Other isolated organisms were S. aureus (13.4% vs. 19.0%, Pseudomonas aeruginosa (10.3% vs. 2.4%, Klebsiella pneumoniae (7.2% vs. 7.1% and K. aerogenes (7.2% vs. 1.2%. Resistance rate of uropathogens to antibiotics was higher among in-patients. Resistance rate to ofloxacin, ceftazidime and ceftriaxone was generally very low compared to other tested antibiotics. Multiple resistant bacteria: MRSA and ESBL-producing enterobacteria were detected among both in-and out-patient with no significant difference in isolation rate. Conclusion: There is a need for continuous monitoring of uropathogens and their antibiotic sensitivity profile for evidence-based empirical treatment of UTI. There is an urgent need for the establishment of antibiotic

  9. Evaluation of anti-bacterial and anti-oxidant potential of andrographolide and echiodinin isolated from callus culture of Andrographis paniculata Nees

    Institute of Scientific and Technical Information of China (English)

    Mohammed Arifullah; Nima Dandu Namsa; Manabendra Mandal; Kishore Kumar Chiruvella; Paritala Vikrama; Ghanta Rama Gopal

    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 Mycobacteriumsmegmatis, 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.

  10. Isolated thallus-associated compounds from the macroalga Fucus vesiculosus mediate bacterial surface colonization in the field similar to that on the natural alga.

    Science.gov (United States)

    Lachnit, Tim; Wahl, Martin; Harder, Tilmann

    2010-01-01

    This study investigated whether surface-associated compounds isolated from the macroalga Fucus vesiculosus had the potential to mediate microbial and/or macrobial epibiosis similar to that on the natural alga. To selectively yield thallus-associated compounds and avoid contamination by intracellular algal compounds, cell lysis was monitored by surface microscopy of algal cells and chemical profiling of algal surface extracts by coupled gas chromatography mass spectroscopy. The optimized extraction resulted in polar and non-polar algal surface extracts. The non-polar surface extract was immobilized in hydrogel, the polar surface extract was homogeneously perfused through the gel to ensure a temporally constant delivery of polar extract components. During a 7 day field trial, bacterial biofilms were formed on control gels and gels featuring polar and/or non-polar extract components. PERMANOVA revealed that bacterial community profiles on controls and on gels featuring polar or non-polar extract were significantly different from the profile on F. vesiculosus, while the profile on the gels bearing both polar and non-polar extracts was not. Moreover, the polar surface extracts inhibited the settlement of barnacle cyprids. Considering the pronounced effects of bacterial biofilms on invertebrate larval settlement, these results suggest that algal surface chemistry affects macrofouling not only directly but also indirectly, via its control of biofilm formation and composition.

  11. 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)

  12. Prevalence and current antibiogram trend of bacterial isolates of urinary tract infections in outpatients at Helping Hands Community Hospital, Kathmandu, Nepal

    Institute of Scientific and Technical Information of China (English)

    Sunil Pandey; Bivek Timalsina

    2016-01-01

    Objective:To ascertain the prevalence and antibiotic susceptibility pattern of bacteria from urinary tract infections. Methods:A retrospective analysis of bacterial pathogens and antibiogram was done in Helping Hands Community Hospital Laboratory from August to November, 2014. Results:The prevalence of bacterial isolates was higher among females (44.70%) than males (31.34%) (P<0.001). The most common bacteria were Escherichia coli 35 (59.32%), followed by coagulase-negative Staphylococcus 5 (8.47%), Salmonella enterica 4 (6.78%), Proteus mirabilis 2 (3.39%), Proteus vulgaris 2 (3.39%), Klebsiella pneumoniae 2 (3.39%), Salmonella typhi 2 (3.39%), Pseudomonas species 2 (3.39%), Staphylococcus aureus 2 (3.39%), Citrobacter species 2 (3.39%), Acinetobacter baumannii 1 (1.69%), Acinetobacter species 1 (1.69%), Proteus vulgaris 1 (1.69%). Conclusions:Most Gram-positive isolates were sensitive to nitrofurantoin, gentamycin and norfloxacin, and they are considered as appropriate microbials for empirical treatment of urinary tract infections.

  13. Purification of bacterial genomic DNA in less than 20 min using chelex-100 microwave: examples from strains of lactic acid bacteria isolated from soil samples.

    Science.gov (United States)

    Reyes-Escogido, Lourdes; Balam-Chi, Mario; Rodríguez-Buenfil, Ingrid; Valdés, Jesús; Kameyama, Luis; Martínez-Pérez, Francisco

    2010-11-01

    We established a Chelex 100-Microwave method for the purification of bacterial genomic DNA (gDNA) in less than 20 min with high yield and good quality, useful for multiple purposes. It combines Chelex 100, proteinase K, RNase A and heating in a microwave oven. The resulting gDNA was used directly to identify bacterial species of the Order Lactobacillales by means of PCR amplification of their 16S rDNA gene, isolated from sediments on the Yucatan Peninsula, Mexico. This method produced gDNA free of phenolic and protein residual contaminants from 100 of these isolated bacteria. 16S rDNA amplification and sequencing showed Pediococcus acidilactici to prevail in inland lagoons, and Pediococcus pentosaceus, Lactobacillus plantarum, Lactobacillus sp., and Lactobacillus fermentum to be most abundant in the soils of livestock farms. The combination of Chelex 100, enzymes and microwave heating used in the Chelex 100-Microwave method produced large amounts of highly pure gDNA from Gram-positive and Gram-negative bacteria, in less than 20 min.

  14. In vitro activity of Melaleuca alternifolia (tea tree) oil against bacterial and Candida spp. isolates from clinical specimens.

    Science.gov (United States)

    Banes-Marshall, L; Cawley, P; Phillips, C A

    2001-01-01

    This study investigates the in vitro activity of tea tree oil (TTO) against a range of wild strains of microorganisms isolated from clinical specimens of leg ulcers and pressure sores. The antimicrobial effectiveness of TTO is determined in terms of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC). The isolates include methicillin-resistant Staphylococcus aureus (MRSA), S. aureus, faecal streptococci, beta-haemolytic streptococci, coagulase-negative staphylococci, Pseudomonas spp. and coliform bacilli. Eleven Candida spp. isolates from skin and vaginal swabs also are tested. Using an agar dilution assay, the MICs of TTO in 88 out of 90 isolates was 0.5-1.0% (v/v), whilst with P. aeruginosa it was >2% (v/v). A broth microdilution method was used to determine MIC and minimum cidal concentration (MCC) of 80 isolates. In 64 isolates, TTO produced an inhibitory and cidal effect at 3% and 4% (v/v), respectively. S. aureus and Candida spp. were the most susceptible to TTO, with MICs and MBCs of 0.5% and 1%, respectively. P. aeruginosa and the faecal streptococci isolates, with MICs and MBCs of >8%, were resistant to TTO.

  15. Evaluation of radiation resistance of the bacterial contaminants from femoral heads processed for allogeneic transplantation

    Science.gov (United States)

    Singh, Rita; Singh, Durgeshwer

    2009-09-01

    Femoral heads excised during surgery were obtained from patients who had a fractured neck of the femur and were processed as bone allograft. The bacterial contaminants were isolated from femoral heads at different stages of processing and identified based on morphological characteristics and biochemical tests. Bacterial contaminants on bone were mainly Gram-positive bacilli and cocci (58.3%). Twenty-four isolates from bone samples were screened for resistance to radiation. The D10 values for Gram-negative bacteria isolated from femoral heads ranged from 0.17 to 0.65 kGy. Higher D10 values 0.56-1.04 kGy were observed for Gram-positive bacterial isolates.

  16. Evaluation of radiation resistance of the bacterial contaminants from femoral heads processed for allogeneic transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Rita [Radiation Dosimetry and Processing Group, Defence Laboratory, Jodhpur 342011 (India)], E-mail: singhritadr@yahoo.com; Singh, Durgeshwer [Radiation Dosimetry and Processing Group, Defence Laboratory, Jodhpur 342011 (India)

    2009-09-15

    Femoral heads excised during surgery were obtained from patients who had a fractured neck of the femur and were processed as bone allograft. The bacterial contaminants were isolated from femoral heads at different stages of processing and identified based on morphological characteristics and biochemical tests. Bacterial contaminants on bone were mainly Gram-positive bacilli and cocci (58.3%). Twenty-four isolates from bone samples were screened for resistance to radiation. The D{sub 10} values for Gram-negative bacteria isolated from femoral heads ranged from 0.17 to 0.65 kGy. Higher D{sub 10} values 0.56-1.04 kGy were observed for Gram-positive bacterial isolates.

  17. Twenty years of dendrotoxins.

    Science.gov (United States)

    Harvey, A L

    2001-01-01

    Dendrotoxins are small proteins that were isolated 20 years ago from mamba (Dendroaspis) snake venoms (Harvey, A.L., Karlsson, E., 1980. Dendrotoxin from the venom of the green mamba, Dendroaspis angusticeps: a neurotoxin that enhances acetylcholine release at neuromuscular junctions. Naunyn-Schmiedebergs Arch. Pharmacol. 312, 1-6.). Subsequently, a family of related proteins was found in mamba venoms and shown to be homologous to Kunitz-type serine protease inhibitors, such as aprotinin. The dendrotoxins contain 57-60 amino acid residues cross-linked by three disulphide bridges. The dendrotoxins have little or no anti-protease activity, but they were demonstrated to block particular subtypes of voltage-dependent potassium channels in neurons. Studies with cloned K(+) channels indicate that alpha-dendrotoxin from green mamba Dendroaspis angusticeps blocks Kv1.1, Kv1.2 and Kv1.6 channels in the nanomolar range, whereas toxin K from the black mamba Dendroaspis polylepis preferentially blocks Kv1.1 channels. Structural analogues of dendrotoxins have helped to define the molecular recognition properties of different types of K(+) channels, and radiolabelled dendrotoxins have also been useful in helping to discover toxins from other sources that bind to K(+) channels. Because dendrotoxins are useful markers of subtypes of K(+) channels in vivo, dendrotoxins have become widely used as probes for studying the function of K(+) channels in physiology and pathophysiology.

  18. Pathogenic Staphylococcus aureus Isolates from Postoperative Wounds of Hospitalized Patients

    Directory of Open Access Journals (Sweden)

    Smritikana Biswas

    2010-07-01

    Full Text Available Staphylococcus sp., gram positive pyogenic bacteria located on skin, nose etc, secretes toxin that causes toxic shock syndrome, abscess, food poisoning and other infectious diseases. This study was carried out to identify and characterize the type of Staphylococcus sp. bacteria especially Staphylococcus aureus in the pus from postoperative wounds of hospitalized patients. From pus samples collected from twenty-four patients from Kharagpur Hospital, Paschim Medinipur, West Bengal, twenty-eight bacterial isolates were obtained. Among them twenty-five (89.2% were appeared with golden yellow colonies which is usually formed by Staphylococcus aureus. Twenty-three (82.14% of the bacterial isolates were Gram positive. Among them twenty isolates (86.9% were further confirmed to be Staphylococcus aureus by their ability to produce Catalase enzyme (positive in Catalase test and Coagulase enzyme (positive in Coagulase Test. Eighteen (90.00% of these Staphylococcus aureus were found to liquefy gelatin (Gelatin hydrolysis test, were able to hydrolyze urea (Urea hydrolysis test and were also l positive in Mannitol Fermentation Test. But there was no growth found of these isolates on MacConkey Agar, while sixteen isolates (80.00% of Staphylococcus aureus were resistant to penicillin (50µg/ml. Moreover eighteen (90.00% Staphylococcus aureus isolates were able to elaborate Hemolysin (Hemolysis test on Blood Agar media. Hence the bacterial isolates obtained from pus of postoperative wounds were predominantly pathogenic Staphylococcus aureus. So it can be concluded that careful treatment and postoperative measures to be taken to avoid serious health problem that may often be life threatening.

  19. ORIGINAL ARTICLE: Detection of β-Lactamase Activity in Various Clinical Bacterial Isolates by Three Different Methods and its Correlation with Drug Resistance.

    Directory of Open Access Journals (Sweden)

    Sanjay M Wavare

    2012-07-01

    Full Text Available Background: β-lactams such as penicillins are the most widely used antibiotics, and β-lactamases are the greatest source of resistance to penicillins. Aims and Objectives: To study β-lactamase production in clinical isolates of family Enterobacteriaceae, P. aeruginosa and Staphylococci by three different methods and to correlate its potential with drug resistance; with an endeavour to evaluate convenient and economical method duly supported by relevant Minimum Inhibitory Concentration (MIC studies. Material and Methods: Total 240 clinical isolates (Gram-negative bacilli-191, staphylococci-49 were subjected to antimicrobial susceptibility testing by Kirby-Bauer disk diffusion method and MIC for ampicillin and penicillin was determined by agar dilution method. β-lactamase was detected by broth acidometric, iodometric cell suspension and microbiological method. Results: Multidrug resistance was observed in more than 90% isolates. One hundred and ninety Gram-negative bacilli were resistant to ampicillin and 47 staphylococcal isolates were resistant to both penicillin and ampicillin. Though microbiological method gave highest positive results 210 (87.5%, iodometric method could detect β-lactamase in apparently sensitive isolates as well giving satisfactory [207 (86.25%] comparable results. Conclusion: In view of the noted bacterial resistance, tests for β-lactamase should be carried out on a routine basis for an early implementation of appropriate antimicrobial therapy. Iodometric method is eminently convenient, economical and reliable method. Isolates showing MIC <0.125µg/ml for penicillin and MIC <8µg/ml for ampicillin should be checked for β-lactamase production.

  20. 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.

  1. ISOLATION AND IDENTIFICATION OF BACTERIAL CAUSED SOFT ROT DISEASE ON CARROT (Daucus carota L. LOCAL VARIETY IN BALI

    Directory of Open Access Journals (Sweden)

    Ni Wayan Desi Bintari

    2015-03-01

    Full Text Available Soft rot bacteria infection in carrot tuber (D. carota L. causes severe economic losses. Soft rot disease can be caused by various bacteria belonging to Enterobacteriaceae. This study aimed to isolate and identify bacteria as causal agent of soft rot disease in local carrot variety in Bali. Samples were collected at Badung Tradisional Market, Denpasar, Bali. Isolation was carried out by serial dilution method (Platting Method. Eight bacteria (BL1, BL2, BL3, BL4, BL5, BL6, BL7 and BL8 were isolated from soft rot tuber. BL6 isolate showed positive result in Postulat Koch test that caused soft rot on carrot tuber. The result of identification by Microgen™ GnA+B-ID System and identification book Bergeys’s Manual of Determinative Bacteriology Ninth Edition (Holt et al., 1994, BL6 was identified as Citrobacter.

  2. Persistent Staphylococcus aureus Isolates from Two Independent Cases of Bacteremia Display Increased Bacterial Fitness and Novel Immune Evasion Phenotypes

    OpenAIRE

    Richards, R L; Haigh, R. D.; Pascoe, B.; Sheppard, S.K.; Price, F.; Jenkins, D.; Rajakumar, K; Morrissey, J. A.

    2015-01-01

    Staphylococcus aureus bacteremia cases are complicated by bacterial persistence and treatment failure despite the confirmed in vitro susceptibility of the infecting strain to administered antibiotics. A high incidence of methicillin-resistant S. aureus (MRSA) bacteremia cases are classified as persistent and are associated with poorer patient outcomes. It is still unclear how S. aureus evades the host immune system and resists antibiotic treatment for the prolonged duration of a persistent in...

  3. 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.

  4. 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.

  5. The metabolism of neonicotinoid insecticide thiamethoxam by soil enrichment cultures, and the bacterial diversity and plant growth-promoting properties of the cultured isolates.

    Science.gov (United States)

    Zhou, Guang-Can; Wang, Ying; Ma, Yuan; Zhai, Shan; Zhou, Ling-Yan; Dai, Yi-Jun; Yuan, Sheng

    2014-01-01

    A soil enrichment culture (SEC) rapidly degraded 96% of 200 mg L(-1) neonicotinoid insecticide thiamethoxam (TMX) in MSM broth within 30 d; therefore, its metabolic pathway of TMX, bacterial diversity and plant growth-promoting rhizobacteria (PGPR) activities of the cultured isolates were studied. The SEC transformed TMX via the nitro reduction pathway to form nitrso, urea metabolites and via cleavage of the oxadiazine cycle to form a new metabolite, hydroxyl CLO-tri. In addition, 16S rRNA gene-denaturing gradient gel electrophoresis analysis revealed that uncultured rhizobacteria are predominant in the SEC broth and that 77.8% of the identified bacteria belonged to uncultured bacteria. A total of 31 cultured bacterial strains including six genera (Achromobacter, Agromyces, Ensifer, Mesorhizobium, Microbacterium and Pseudoxanthomonas) were isolated from the SEC broth. The 12 strains of Ensifer adhaerens have the ability to degrade TMX. All six selected bacteria showed PGPR activities. E. adhaerens TMX-23 and Agromyces mediolanus TMX-25 produced indole-3-acetic acid, whereas E. adhaerens TMX-23 and Mesorhizobium alhagi TMX-36 are N2-fixing bacteria. The six-isolated microbes were tolerant to 200 mg L(-1) TMX, and the growth of E. adhaerens was significantly enhanced by TMX, whereas that of Achromobacter sp. TMX-5 and Microbacterium sp.TMX-6 were enhanced slightly. The present study will help to explain the fate of TMX in the environment and its microbial degradation mechanism, as well as to facilitate future investigations of the mechanism through which TMX enhances plant vigor.

  6. Bacterial Diversity of Ny-Ålesund, Arctic Archipelago Svalbard

    Directory of Open Access Journals (Sweden)

    Battsetseg Choidash

    2012-12-01

    Full Text Available The bacterial diversity of the water sample, collected from Ny-Ålesund, Arctic Archipelago Svalbard was analyzed by a phenotypic as well as a genotypic approach. Pure colonies of the culturable bacteria were established and grown at a range of temperatures: 4ºC, 15ºC, 22ºC and 37ºC. Optimum growth was found at 15ºC, and around 28 colonies were obtained. The library was dominated by 16S rDNAs of Gram-negative bacteria ( γ -Proteobacteria. Twenty two isolates exhibited sequences were similar to that of known bacterial isolates (>97% sequence similarity, represented by the species of the genera Psychrobacter , Pseudomonas , and Acinetobacter . Six isolates exhibited sequences showed less affi liation with known taxa (<97% sequence similarity, and may represent novel taxa.

  7. Outlook: The Next Twenty Years

    Energy Technology Data Exchange (ETDEWEB)

    Murayama, Hitoshi

    2003-12-07

    I present an outlook for the next twenty years in particle physics. I start with the big questions in our field, broken down into four categories: horizontal, vertical, heaven, and hell. Then I discuss how we attack the bigquestions in each category during the next twenty years. I argue for a synergy between many different approaches taken in our field.

  8. Isolation

    DEFF Research Database (Denmark)

    Agerholm, Frank Juul

    2011-01-01

    Næringsstoffet har i dette nummer sat fokus på ”velvære i vinterkulden”, ”indendørsaktiviteter” og ”fedtafgift”. I klummen vises det, at disse tre fokusområder, der for en umiddelbar betragtning måske nok synes noget uensartede, falder sammen i ét tema: Isolation!......Næringsstoffet har i dette nummer sat fokus på ”velvære i vinterkulden”, ”indendørsaktiviteter” og ”fedtafgift”. I klummen vises det, at disse tre fokusområder, der for en umiddelbar betragtning måske nok synes noget uensartede, falder sammen i ét tema: Isolation!...

  9. Isolation and characterization of bacteria with antibacterial properties from Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Etyemez, Miray; Balcazar, Jose Luis

    2016-04-01

    One hundred and twenty bacterial isolates were obtained from the intestinal mucus of Nile tilapia (Oreochromis niloticus) and screened for antagonistic activity and adherence abilities. Based on in vitro antagonism against two pathogens (Streptococcus iniae and Edwardsiella piscicida), five isolates were selected and identified by 16S rRNA gene sequence analysis. All antagonistic isolates were affiliated to the genus Bacillus, which showed inhibitory activity against S. iniae. Only the isolate B191 (closely related to Bacillus mojavensis) inhibited the growth of both pathogens. Moreover, isolate B191 adhered significantly better to fish intestinal mucus than other antagonistic isolates. According to our results, these bacterial isolates, particularly isolate B191, should be further studied to explore their probiotic effects under in vivo conditions.

  10. ISOLATION AND IDENTIFICATION OF BACTERIAL CAUSED SOFT ROT DISEASE ON CARROT (Daucus carota L.) LOCAL VARIETY IN BALI

    OpenAIRE

    Ni Wayan Desi Bintari; Retno Kawuri; Meitini Wahyuni Proborini

    2015-01-01

    Soft rot bacteria infection in carrot tuber (D. carota L.) causes severe economic losses. Soft rot disease can be caused by various bacteria belonging to Enterobacteriaceae. This study aimed to isolate and identify bacteria as causal agent of soft rot disease in local carrot variety in Bali. Samples were collected at Badung Tradisional Market, Denpasar, Bali. Isolation was carried out by serial dilution method (Platting Method). Eight bacteria (BL1, BL2, BL3, BL4, BL5, BL6, BL7 and BL8) were ...

  11. Isolation and characterization of bacterial strains with a hydrolytic profile with potential use in bioconversion of agroindustial by-products and waste

    Directory of Open Access Journals (Sweden)

    Cintia Anabela Mazzucotelli

    2013-06-01

    Full Text Available There is a trend towards the use of novel technologies nowadays, mainly focused on biological processes, for recycling and the efficient utilization of organic residues that can be metabolized by different microorganisms as a source of energy. In the present study the isolation of bacterial strains from six different agro-industrial by-products and waste was performed with the objective of evaluating their hydrolytic capacities and suitability for use in bioconversion of specific substrates. The 34 isolated strains were screened in specific culture media for the production of various hydrolytic enzymes (lipase, protease, cellulase, and amylase. It was found that 28 strains exhibited proteolytic activity, 18 had lipolytic activity, 13 had caseinolytic activity, 15 had amylolytic activity, and 11 strains exhibited cellulolytic activity. The strains that showed the highest hydrolytic capacities with biotechnological potential were selected, characterized genotipically, and identified as Bacillus, Serratia, Enterococcus, Klebsiella, Stenotrophomonas, Lactococcus, and Escherichia genera. It was concluded that the strain isolates have a high potential for use in the bioconversion of agro-industrial waste, both as a pure culture and as a microbial consortium.

  12. Unusual long-chain N-acyl homoserine lactone production by and presence of quorum quenching activity in bacterial isolates from diseased tilapia fish.

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    Chien-Yi Chang

    Full Text Available Growth-dependent cell-cell communication termed quorum sensing is a key regulatory system in bacteria for controlling gene expression including virulence factors. In this study five potential bacterial pathogens including Bacillus sp. W2.2, Klebsiella sp. W4.2, Pseudomonas sp. W3 and W3.1 and Serratia sp. W2.3 were isolated from diseased Tilapia fish in Malaysia, supplied by the leading global fish supplier. Proteolytic activity assays confirmed that with the exception of Klebsiella sp. W4.2, all isolates showed distinct proteolytic activity. Furthermore Bacillus sp. W2.2 and Pseudomonas sp. strains W3 and W3.1 also displayed haemolytic activity. By using high resolution liquid chromatography mass spectrometry, we revealed the presence of unusually long-chain N-(3-oxohexadecanoyl-homoserine lactone (3-oxo-C16-HSL from Pseudomonas sp. W3.1 and N-dodecanoyl-homoserine lactone (C12-HSL from Serratia sp. W2.3, respectively. Interestingly, Pseudomonas sp. W3.1 also produced a wide range of Pseudomonas quinolone signalling (PQS molecules. Pseudomonas sp. W3 did not show any quorum sensing properties but possessed quorum quenching activity that inactivated AHLs. This study is the first documentation that shows unusual long-chain AHLs production in Serratia sp. and Pseudomonas sp. isolated from diseased fish and the latter also produce a wide range of PQS molecules.

  13. Evaluation of Antimicrobial Activity of Cuminum Cyminum Essential Oil and Extract against Bacterial Strains Isolated from Patients with Symptomatic Urinary Tract Infection

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    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.

  14. A comparative study of bacterial isolates from the urine samples of AIDS and non-AIDS patients in Benue, Nigeria

    Institute of Scientific and Technical Information of China (English)

    Okwori EE; Nwadioha SI; Jombo GTA; Nwokedi EOP; Odimayo MS

    2010-01-01

    Objective:To determine the common bacterial causes of urinary tract infection and their antibiotic susceptibility pattern in AIDS patients versus non-AIDS patients. Methods: One thousand consecutive AIDS patients with signs and symptoms of AIDS and non-AIDS patients (served as control) each on admission were recruited into the study between January 2005 to January 2008, in Federal Medical Center, Makurdi. Urine samples were collected with sterile universal bottles and analysed with appropriate laboratory methods and antibiotic susceptibility test was carried out by disk diffusion technique in accordance with National Committee for Clinical Laboratory Standards (NCCLS, now CLSI) criteria. The results were analysed using SPSS 11.0 statistical software. Results:Urine samples of AIDS patients with urinary infection had a more spectrum of micro-organisms including Candida organisms, Pseudomonas aeruginosa and Staphylococcus aureus. Ceftriaxone, Ceftazidime or Ciprofloxacin had a remarkably high anti-bacterial activity across the two study groups. A general resistance was recorded in ampicillin, tetracycline and co-trimoxazole. There was no significant difference in antibiotic susceptibility patterns between AIDS and non-AIDS patients(P>0.05). Conclusions:A reduction in unnecessary use of antibiotics as well as infection control should be encouraged in our health facilities.

  15. Effective biodegradation of 2,4,6-trinitrotoluene using a novel bacterial strain isolated from TNT-contaminated soil

    NARCIS (Netherlands)

    Gümüscü, B.; Tekinay, Turgay

    2013-01-01

    In this environmental-sample based study, rapid microbial-mediated degradation of 2,4,6-trinitrotoluene (TNT) contaminated soils is demonstrated by a novel strain, Achromobacter spanius STE 11. Complete removal of 100 mg L−1 TNT is achieved within only 20 h under aerobic conditions by the isolate. I

  16. 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.

  17. Draft Genome Sequence of Burkholderia sp. MR1, a Methylarsenate-Reducing Bacterial Isolate from Florida Golf Course Soil

    Science.gov (United States)

    Pawitwar, Shashank S.; Utturkar, Sagar M.; Brown, Steven D.; Yoshinaga, Masafumi

    2015-01-01

    To elucidate the environmental organoarsenical biocycle, we isolated a soil organism, Burkholderia sp. MR1, which reduces relatively nontoxic pentavalent methylarsenate to the more toxic trivalent methylarsenite, with the goal of identifying the gene for the reductase. Here, we report the draft genome sequence of Burkholderia sp. MR1. PMID:26044439

  18. Draft Genome Sequence of Burkholderia sp. MR1, a Methylarsenate-Reducing Bacterial Isolate from Florida Golf Course Soil

    OpenAIRE

    Pawitwar, Shashank S.; Utturkar, Sagar M.; Brown, Steven D.; Yoshinaga, Masafumi; Rosen, Barry P.

    2015-01-01

    To elucidate the environmental organoarsenical biocycle, we isolated a soil organism, Burkholderia sp. MR1, which reduces relatively nontoxic pentavalent methylarsenate to the more toxic trivalent methylarsenite, with the goal of identifying the gene for the reductase. Here, we report the draft genome sequence of Burkholderia sp. MR1.

  19. Bio-precipitation of uranium by two bacterial isolates recovered from extreme environments as estimated by potentiometric titration, TEM and X-ray absorption spectroscopic analyses

    Energy Technology Data Exchange (ETDEWEB)

    Merroun, Mohamed L., E-mail: merroun@ugr.es [Institute of Radiochemistry, Helmholtz Centre Dresden-Rossendorf, Dresden (Germany); Departamento de Microbiologia, Universidad de Granada, Campus Fuentenueva s/n 18071, Granada (Spain); Nedelkova, Marta [Institute of Radiochemistry, Helmholtz Centre Dresden-Rossendorf, Dresden (Germany); Ojeda, Jesus J. [Cell-Mineral Interface Research Programme, Kroto Research Institute, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); Experimental Techniques Centre, Brunel University, Uxbridge, Middlesex UB8 3PH (United Kingdom); Reitz, Thomas [Institute of Radiochemistry, Helmholtz Centre Dresden-Rossendorf, Dresden (Germany); Fernandez, Margarita Lopez; Arias, Jose M. [Departamento de Microbiologia, Universidad de Granada, Campus Fuentenueva s/n 18071, Granada (Spain); Romero-Gonzalez, Maria [Cell-Mineral Interface Research Programme, Kroto Research Institute, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); Selenska-Pobell, Sonja [Institute of Radiochemistry, Helmholtz Centre Dresden-Rossendorf, Dresden (Germany)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Precipitation of uranium as U phosphates by natural bacterial isolates. Black-Right-Pointing-Pointer The uranium biomineralization involves the activity of acidic phosphatase. Black-Right-Pointing-Pointer Uranium bioremediation could be achieved via the biomineralization of U(VI) in phosphate minerals. - Abstract: This work describes the mechanisms of uranium biomineralization at acidic conditions by Bacillus sphaericus JG-7B and Sphingomonas sp. S15-S1 both recovered from extreme environments. The U-bacterial interaction experiments were performed at low pH values (2.0-4.5) where the uranium aqueous speciation is dominated by highly mobile uranyl ions. X-ray absorption spectroscopy (XAS) showed that the cells of the studied strains precipitated uranium at pH 3.0 and 4.5 as a uranium phosphate mineral phase belonging to the meta-autunite group. Transmission electron microscopic (TEM) analyses showed strain-specific localization of the uranium precipitates. In the case of B. sphaericus JG-7B, the U(VI) precipitate was bound to the cell wall. Whereas for Sphingomonas sp. S15-S1, the U(VI) precipitates were observed both on the cell surface and intracellularly. The observed U(VI) biomineralization was associated with the activity of indigenous acid phosphatase detected at these pH values in the absence of an organic phosphate substrate. The biomineralization of uranium was not observed at pH 2.0, and U(VI) formed complexes with organophosphate ligands from the cells. This study increases the number of bacterial strains that have been demonstrated to precipitate uranium phosphates at acidic conditions via the activity of acid phosphatase.

  20. Inhibitory effect of pomegranate (Punica granatum L.) polyphenol extracts on the bacterial growth and survival of clinical isolates of pathogenic Staphylococcus aureus and Escherichia coli.

    Science.gov (United States)

    Pagliarulo, Caterina; De Vito, Valentina; Picariello, Gianluca; Colicchio, Roberta; Pastore, Gabiria; Salvatore, Paola; Volpe, Maria Grazia

    2016-01-01

    In the present study major polyphenols of pomegranate arils and peel by-products were extracted in 50% (v/v) aqueous ethanol, characterized and used in microbiological assays in order to test antimicrobial activity against clinically isolated human pathogenic microorganisms. Total concentration of polyphenols and in vitro antioxidant properties were determined by the Folin-Ciocalteu and DPPH methods, respectively. The most abundant bioactive molecules, including anthocyanins, catechins, tannins, gallic and ellagic acids were identified by RP-HPLC-DAD, also coupled to off-line matrix assisted laser desorption/ionization (MALDI-TOF) mass spectrometry (MS). The inhibitory spectrum of extracts against test microorganisms was assessed by the agar well-diffusion method. Data herein indicated that both pomegranate aril and peel extracts have an effective antimicrobial activity, as evidenced by the inhibitory effect on the bacterial growth of two important human pathogens, including Staphylococcus aureus and Escherichia coli, which are often involved in foodborne illness.

  1. Determination of selected pesticides in water samples adjacent to agricultural fields and removal of organophosphorus insecticide chlorpyrifos using soil bacterial isolates

    Science.gov (United States)

    Hossain, M. S.; Chowdhury, M. Alamgir Zaman; Pramanik, Md. Kamruzzaman; Rahman, M. A.; Fakhruddin, A. N. M.; Alam, M. Khorshed

    2015-06-01

    The use of pesticide for crops leads to serious environmental pollution, therefore, it is essential to monitor and develop approaches to remove pesticide from contaminated environment. In this study, water samples were collected to monitor pesticide residues, and degradation of chlorpyrifos was also performed using soil bacteria. Identification of pesticide residues and determination of their levels were performed by high-performance liquid chromatography with photodiode array detector. Among 12 samples, 10 samples were found contaminated with pesticides. Chlorpyrifos was detected in four tested samples and concentrations ranged from 3.27 to 9.31 μg/l whereas fenitrothion ranging from (Below Detection Limit, pesticide residues in water, to protect the aquatic environment. Chlorpyrifos degrading bacterial isolates can be used to clean up environmental samples contaminated with the organophosphate pesticides.

  2. The Antimicrobial Activity o f Honey o n Bacterial Isolates From Burns/Wound o f Patients Attending General Hospital, Ankpa, Kogi State. Nigeria

    Directory of Open Access Journals (Sweden)

    Aliyu Aminu Ibrahim

    2016-05-01

    Full Text Available The antimicrobial activity of honey samples from Ankpa, Enjema and Ojoku districts of Ankpa Local Government Area of Kogi State, Nigeria against coagulase negative Staphylococcus species, Pseudomonas aeruginosa, coagulase positive Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli and Proteus speciesobtained from 200 burns/wound patients attending General Hospital, Ankpa were determined. The sensitivity of honey to the test organisms ranges from 16mm to 19mm in diameter. The minimum inhibitory concentration (MIC of the honey samples on the bacterial isolates from Ankpa and Ojoku were 0.16 v/v and 0.32 v/v for honey from Enjema. The results of the study revealed that honey from the area understudy has high antimicrobial activity and it is recommended that pure natural honey should be stocked in hospitals/clinics so as to encourage its application in the treatment of burns/wound infections

  3. The identification of a bacterial strain BGI-1 isolated from the intestinal flora of Blattella germanica, and its anti-entomopathogenic fungi activity.

    Science.gov (United States)

    Huang, Y H; Wang, X J; Zhang, F; Huo, X B; Fu, R S; Liu, J J; Sun, W B; Kang, D M; Jing, X

    2013-02-01

    A bacterial strain BGI-1 was isolated from the gut of German cockroaches (Blattella germanica L.) and was identified as Bacillus subtilis based on 16S rDNA sequence and morphological, physiological, and biochemical characters. The strain BGI-1 inhibited the growth of Beauveria bassiana; the diameter of the inhibition zone exceeded 30 mm. Vesicles were observed in B. bassiana hyphae on the edge of the inhibition zone. Fermentation of BGI-1 reduced the conidial germination rate by 12%. Further studies demonstrated that B. bassiana infections in German cockroaches orally treated with the extracts of BGI-1 fermentation were significantly weakened. Cumulative mortality rate was 49.5% in the treatment group at the 20 d, while that of the control group was 62.3%. The study intends to understand the relationship between the intestinal flora and the cockroach. Those microbes with anti-entomopathogenic fungi activity might contribute to resisting the infection of pathogenic fungi.

  4. Isolation, crystallization, and investigation of ribosomal protein S8 complexed with specific fragments of rRNA of bacterial or archaeal origin.

    Science.gov (United States)

    Tishchenko, S V; Vassilieva, J M; Platonova, O B; Serganov, A A; Fomenkova, N P; Mudrik, E S; Piendl, W; Ehresmann, C; Ehresmann, B; Garber, M B

    2001-09-01

    The core ribosomal protein S8 binds to the central domain of 16S rRNA independently of other ribosomal proteins and is required for assembling the 30S subunit. It has been shown with E. coli ribosomes that a short rRNA fragment restricted by nucleotides 588-602 and 636-651 is sufficient for strong and specific protein S8 binding. In this work, we studied the complexes formed by ribosomal protein S8 from Thermus thermophilus and Methanococcus jannaschii with short rRNA fragments isolated from the same organisms. The dissociation constants of the complexes of protein S8 with rRNA fragments were determined. Based on the results of binding experiments, rRNA fragments of different length were designed and synthesized in preparative amounts in vitro using T7 RNA-polymerase. Stable S8-RNA complexes were crystallized. Crystals were obtained both for homologous bacterial and archaeal complexes and for hybrid complexes of archaeal protein with bacterial rRNA. Crystals of the complex of protein S8 from M. jannaschii with the 37-nucleotide rRNA fragment from the same organism suitable for X-ray analysis were obtained.

  5. Silver- and fluoride-containing mesoporous bioactive glasses versus commonly used antibiotics: Activity against multidrug-resistant bacterial strains isolated from patients with burns.

    Science.gov (United States)

    Gholipourmalekabadi, M; Sameni, M; Hashemi, A; Zamani, F; Rostami, A; Mozafari, M

    2016-02-01

    The wound healing process is frequently associated with a number of major clinical challenges, due to the failure of commonly used antibiotics as a remedy for wounds. There have always been fascinating questions about the novel applications of bioactive glasses (BGs) and it is expected that in the next few years these types of materials may play an important role in many aspects of soft tissue regeneration. This research focuses on the feasibility of using silver- and fluoride-containing BGs against multidrug-resistant bacterial strains isolated from patients with burns. According to the results obtained, fluoride did not exhibit antibacterial activity against the tested bacteria, while both 1% and 2% silver-containing BGs inhibited the bacterial growth. It is an important finding that 1% silver-containing BGs showed a potential antibacterial activity without any toxicity against fibroblasts, suggesting that this class of BGs could play a key role in the prevention of infection, reduction of pain, and removal of excessive exudates. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

  6. Comparative Genomics of Field Isolates of Mycobacterium bovis and M. caprae Provides Evidence for Possible Correlates with Bacterial Viability and Virulence.

    Directory of Open Access Journals (Sweden)

    José de la Fuente

    2015-11-01

    Full Text Available Mycobacteria of the Mycobacterium tuberculosis complex (MTBC greatly affect humans and animals worldwide. The life cycle of mycobacteria is complex and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Recently, comparative genomics analyses have provided new insights into the evolution and adaptation of the MTBC to survive inside the host. However, most of this information has been obtained using M. tuberculosis but not other members of the MTBC such as M. bovis and M. caprae. In this study, the genome of three M. bovis (MB1, MB3, MB4 and one M. caprae (MB2 field isolates with different lesion score, prevalence and host distribution phenotypes were sequenced. Genome sequence information was used for whole-genome and protein-targeted comparative genomics analysis with the aim of finding correlates with phenotypic variation with potential implications for tuberculosis (TB disease risk assessment and control. At the whole-genome level the results of the first comparative genomics study of field isolates of M. bovis including M. caprae showed that as previously reported for M. tuberculosis, sequential chromosomal nucleotide substitutions were the main driver of the M. bovis genome evolution. The phylogenetic analysis provided a strong support for the M. bovis/M. caprae clade, but supported M. caprae as a separate species. The comparison of the MB1 and MB4 isolates revealed differences in genome sequence, including gene families that are important for bacterial infection and transmission, thus highlighting differences with functional implications between isolates otherwise classified with the same spoligotype. Strategic protein-targeted analysis using the ESX or type VII secretion system, proteins linking stress response with lipid metabolism, host T cell epitopes of mycobacteria, antigens and peptidoglycan assembly protein identified new genetic markers and candidate vaccine antigens that warrant

  7. Comparative Genomics of Field Isolates of Mycobacterium bovis and M. caprae Provides Evidence for Possible Correlates with Bacterial Viability and Virulence.

    Science.gov (United States)

    de la Fuente, José; Díez-Delgado, Iratxe; Contreras, Marinela; Vicente, Joaquín; Cabezas-Cruz, Alejandro; Tobes, Raquel; Manrique, Marina; López, Vladimir; Romero, Beatriz; Bezos, Javier; Dominguez, Lucas; Sevilla, Iker A; Garrido, Joseba M; Juste, Ramón; Madico, Guillermo; Jones-López, Edward; Gortazar, Christian

    2015-11-01

    Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly affect humans and animals worldwide. The life cycle of mycobacteria is complex and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Recently, comparative genomics analyses have provided new insights into the evolution and adaptation of the MTBC to survive inside the host. However, most of this information has been obtained using M. tuberculosis but not other members of the MTBC such as M. bovis and M. caprae. In this study, the genome of three M. bovis (MB1, MB3, MB4) and one M. caprae (MB2) field isolates with different lesion score, prevalence and host distribution phenotypes were sequenced. Genome sequence information was used for whole-genome and protein-targeted comparative genomics analysis with the aim of finding correlates with phenotypic variation with potential implications for tuberculosis (TB) disease risk assessment and control. At the whole-genome level the results of the first comparative genomics study of field isolates of M. bovis including M. caprae showed that as previously reported for M. tuberculosis, sequential chromosomal nucleotide substitutions were the main driver of the M. bovis genome evolution. The phylogenetic analysis provided a strong support for the M. bovis/M. caprae clade, but supported M. caprae as a separate species. The comparison of the MB1 and MB4 isolates revealed differences in genome sequence, including gene families that are important for bacterial infection and transmission, thus highlighting differences with functional implications between isolates otherwise classified with the same spoligotype. Strategic protein-targeted analysis using the ESX or type VII secretion system, proteins linking stress response with lipid metabolism, host T cell epitopes of mycobacteria, antigens and peptidoglycan assembly protein identified new genetic markers and candidate vaccine antigens that warrant further study to

  8. Comparative Genomics of Field Isolates of Mycobacterium bovis and M. caprae Provides Evidence for Possible Correlates with Bacterial Viability and Virulence

    Science.gov (United States)

    de la Fuente, José; Díez-Delgado, Iratxe; Contreras, Marinela; Vicente, Joaquín; Cabezas-Cruz, Alejandro; Tobes, Raquel; Manrique, Marina; López, Vladimir; Romero, Beatriz; Bezos, Javier; Dominguez, Lucas; Sevilla, Iker A.; Garrido, Joseba M.; Juste, Ramón; Madico, Guillermo; Jones-López, Edward; Gortazar, Christian

    2015-01-01

    Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly affect humans and animals worldwide. The life cycle of mycobacteria is complex and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Recently, comparative genomics analyses have provided new insights into the evolution and adaptation of the MTBC to survive inside the host. However, most of this information has been obtained using M. tuberculosis but not other members of the MTBC such as M. bovis and M. caprae. In this study, the genome of three M. bovis (MB1, MB3, MB4) and one M. caprae (MB2) field isolates with different lesion score, prevalence and host distribution phenotypes were sequenced. Genome sequence information was used for whole-genome and protein-targeted comparative genomics analysis with the aim of finding correlates with phenotypic variation with potential implications for tuberculosis (TB) disease risk assessment and control. At the whole-genome level the results of the first comparative genomics study of field isolates of M. bovis including M. caprae showed that as previously reported for M. tuberculosis, sequential chromosomal nucleotide substitutions were the main driver of the M. bovis genome evolution. The phylogenetic analysis provided a strong support for the M. bovis/M. caprae clade, but supported M. caprae as a separate species. The comparison of the MB1 and MB4 isolates revealed differences in genome sequence, including gene families that are important for bacterial infection and transmission, thus highlighting differences with functional implications between isolates otherwise classified with the same spoligotype. Strategic protein-targeted analysis using the ESX or type VII secretion system, proteins linking stress response with lipid metabolism, host T cell epitopes of mycobacteria, antigens and peptidoglycan assembly protein identified new genetic markers and candidate vaccine antigens that warrant further study to

  9. Antimicrobial Susceptibility Monitoring of Bacterial Pathogens Isolated from Urinary Tract Infections in Dogs and Cats Across Europe: ComPath Results.

    Science.gov (United States)

    Moyaert, Hilde; Morrissey, Ian; de Jong, Anno; El Garch, Farid; Klein, Ulrich; Ludwig, Carolin; Thiry, Julien; Youala, Myriam

    2017-04-01

    ComPath is a pan-European antimicrobial surveillance program collecting bacterial pathogens from dogs and cats not recently exposed to antimicrobials. We present minimum inhibitory concentration data obtained using Clinical and Laboratory Standards Institute methodology for 616 urinary tract infection (UTI) isolates collected between 2008 and 2010. In both dogs and cats, the most common pathogen was Escherichia coli (59.8% and 46.7%, respectively). Antimicrobial activity against E. coli in dogs and cats was similar with fluoroquinolone and trimethoprim/sulfamethoxazole susceptibility >90%. Ampicillin susceptibility was ∼80%. Staphylococcus intermedius Group isolates from dogs (67/437, 15.3%) had high antimicrobial susceptibility (>90%) toward beta-lactams, fluoroquinolones, and trimethoprim/sulfamethoxazole. Four canine isolates (6%) were oxacillin resistant, and harbored mecA. Proteus mirabilis from dogs (48/437, 11.0%) had high antimicrobial susceptibility (∼90%) to amoxicillin/clavulanic acid, enrofloxacin, and marbofloxacin and slightly lower susceptibility (∼80-85%) to ampicillin and orbifloxacin. Streptococcus canis isolates (35/437, 8.0%) from dogs were all susceptible to ampicillin and amoxicillin/clavulanic acid and >90% susceptible to marbofloxacin. Although resistance was not observed, high intermediate susceptibility was seen for both enrofloxacin (28.6%) and orbifloxacin (85.7%). Overall, antimicrobial in vitro activity appears to be high in UTI pathogens from dogs and cats with low multidrug resistance, although a lack of specific dog and cat breakpoints for important antimicrobials such as cefovecin, cephalexin, and ibafloxacin prevents analysis of susceptibility for these agents.

  10. Degradative capacities of bacteria and fungi isolated from a fuel-contaminated soil. Capacites degradatives de bacteries et de champignons isoles d'un sol contamine par un fuel

    Energy Technology Data Exchange (ETDEWEB)

    Oudot, J.; Fusey, P.; Abdelouahid, D.E.; Haloui, S.; Roquebert, M.F. (Museum national d' histoire naturelle, Cedex (France))

    1987-01-01

    The long-term influence of a fuel spill on the bacterial and fungal communities of an agricultural soil was studied. Three years after the contamination, biodegradation of the fuel in the soil was achieved and after 5 years the residual compounds had no significant effect on the density and the specific composition of the microbial populations of the soil. Hydrocarbon-oxidizing bacteria Corynebacterium and Nocardia spp. were isolated. Most of the active fungi were Aspergillus and Penicillium spp., but strains of Paecilomyces, Acremonium, Fusarium, and Gliocladium were also identified. In laboratory experiments, the biodegration rate of a reference crude oil by pure cultures of oil-degrading strains was nearly the same as in mixed cultures. The biodegradation potential of the strains isolated from the control plot was as high as strains isolated from the oiled plot. In the soil, as in laboratory cultures, the saturate hydrocarbons were more degraded than the aromatics, whereas the resins and asphaltenes were resistant to microbial attack, as were polycyclic alkanes, steranes and triterpanes. Nocardia degraded preferentially the aromatics and attacked significantly the asphaltenes, as did Fusarium oxysporum. Aspergillus niger, Aspergillus flavus, and Fusarium oxysporum degraded part of the resins. The spectrum of the initial degradation of petroleum by the most active fungi and bacteria was identical, and it appears that the enzymatic equipment necessary to oxidize hydrocarbons is quite complete in these strains. 21 refs., 9 figs., 5 tabs.

  11. Comparison of commercial DNA extraction kits for isolation and purification of bacterial and eukaryotic DNA from PAH-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoudi, Nagissa; Slater, Greg F.; Fulthorpe, Roberta R.

    2011-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are in the environment and are carcinogenic, teratogenic and mutagenic. Their hydrophobic structure gives them low water solubility and makes them readily absorbed onto soils and sediments, where they persists until they are degraded. Microbial degradation of PAHs has been well documented and is thought to be an important process in remediating contaminated sediments and soils. Obtaining high quality purified DNA is an essential requirement for the successful DNA amplifications that underlie all subsequent procedures. Several commercial DNA extraction kits exist that provide consistent solutions for the central problems - cell lysis and humic acid removal. This study compared four commercial DNA extraction kits to extract pure, high quality bacterial and eukaryotic DNA from PAH contaminated soils and concluded that they can be used on a wide variety of soils, including heavily contaminated soils. The PowerSoil kit was the most effective and reliable.

  12. Ceftobiprole activity against over 60,000 clinical bacterial pathogens isolated in Europe, Turkey, and Israel from 2005 to 2010.

    Science.gov (United States)

    Farrell, David J; Flamm, Robert K; Sader, Helio S; Jones, Ronald N

    2014-07-01

    Ceftobiprole medocaril is a newly approved drug in Europe for the treatment of hospital-acquired pneumonia (HAP) (excluding patients with ventilator-associated pneumonia but including ventilated HAP patients) and community-acquired pneumonia in adults. The aim of this study was to evaluate the in vitro antimicrobial activity of ceftobiprole against prevalent Gram-positive and -negative pathogens isolated in Europe, Turkey, and Israel during 2005 through 2010. A total of 60,084 consecutive, nonduplicate isolates from a wide variety of infections were collected from 33 medical centers. Species identification was confirmed, and all isolates were susceptibility tested using reference broth microdilution methods. Ceftobiprole had high activity against methicillin-susceptible Staphylococcus aureus (MSSA) (100.0% susceptible), methicillin-susceptible coagulase-negative staphylococci (CoNS), beta-hemolytic streptococci, and Streptococcus pneumoniae (99.3% susceptible), with MIC90 values of 0.25, 0.12, ≤ 0.06, and 0.5 μg/ml, respectively. Ceftobiprole was active against methicillin-resistant S. aureus (MRSA) (98.3% susceptible) and methicillin-resistant CoNS, having a MIC90 of 2 μg/ml. Ceftobiprole was active against Enterococcus faecalis (MIC50/90, 0.5/4 μg/ml) but not against most Enterococcus faecium isolates. Ceftobiprole was very potent against the majority of Enterobacteriaceae (87.3% susceptible), with >80% inhibited at ≤ 0.12 μg/ml. The potency of ceftobiprole against Pseudomonas aeruginosa (MIC50/90, 2/>8 μg/ml; 64.6% at MIC values of ≤ 4 μg/ml) was similar to that of ceftazidime (MIC50/90, 2/>16 μg/ml; 75.4% susceptible), but limited activity was observed against Acinetobacter spp. and Stenotrophomonas maltophilia. High activity was also observed against all Haemophilus influenzae (MIC90, ≤ 0.06 μg/ml) and Moraxella catarrhalis (MIC50/90, ≤ 0.06/0.25 μg/ml) isolates. Ceftobiprole demonstrated a wide spectrum of antimicrobial activity against

  13. HPLC based method for the measurement of the reduction of aflatoxin B1 by bacterial cultures isolated from different African foods.

    Science.gov (United States)

    Färber, P; Brost, I; Adam, R; Holzapfel, W

    2000-06-01

    The consumption of fermented foods contaminated with aflatoxin B1 is linked to aflatoxicosis. Aflatoxicosis is a serious problem in developing countries with environmental conditions appropriate for the biosynthesis of AFB1 byAspergillus flavus andAspergillus parasiticus. In Africa, especially in Ghana and Nigeria, there is a very high risk of liver cancer which is caused by the consumption of AFB1-intoxicated, traditionally fermented maize and sorghum products. It is suggested that one way to diminish this health risk might be the reduction of the AFB1 concentration in foods by bacteria. Especially bacteria used for food fermentation processes are of great importance, with a special emphasis on lactic acid bacteria which are involved in traditionally fermented African foods based on maize and sorghum.Most publications dealing with aflatoxin degradation by microorganisms describe a phosphate buffer test system for the performance of degradation experiments. In contrast to that, a test system based on physiological active bacterial and yeast cells has been developed, to assess food fermentation organisms for their ability to reduce the AFB1 concentration in vitro. The aflatoxin B1 concentration in test samples was quatitatively determined by HPLC.The assessment of lactic acid bacteria originating from different German and other European culture collections only showed a very slight reduction of the AFB1 concentration from 3% to 12%. Screening experiments in which other bacterial genera and lactic acid bacteria, isolated from different African foods have been assessed, in most cases showed the same results. However, some bacterial strains, e.g. strains of the genusBacillus derived from European culture collections and strains of the genusLactobacillus isolated from African foods, caused a release of AFB1 which was chemically bound before to components of the test medium and which therefore could not be extracted with chloroform.A process quite similar to that may

  14. Pseudomonas argentinensis sp. nov., a novel yellow pigment-producing bacterial species, isolated from rhizospheric soil in Cordoba, Argentina.

    Science.gov (United States)

    Peix, Alvaro; Berge, Odile; Rivas, Raúl; Abril, Adriana; Velázquez, Encarna

    2005-05-01

    During a study in the Argentinian region of Chaco (Cordoba), some strains were isolated from the rhizosphere of grasses growing in semi-desertic arid soils. Two of these strains, one isolated from the rhizospheric soil of Chloris ciliata (strain CH01(T)) and the other from Pappophorum caespitosum (strain PA01), were Gram-negative, strictly aerobic rods, which formed yellow round colonies on nutrient agar. They produced a water-insoluble yellow pigment, and a fluorescent pigment was also detected. A polyphasic taxonomic approach was used to characterize the strains. Comparison of the 16S rRNA gene sequences showed a similarity of 99.3 % between them, and phylogenetic analysis revealed that the strains belong to the genus Pseudomonas, within the gamma-subclass of the Proteobacteria. The closest related species is Pseudomonas straminea IAM 1598(T) (similarity of 99.0 % to strain CH01(T) and 98.8 % to strain PA01), clustering in a separate branch with the various methods of tree building used. Strains CH01(T) and PA01 both had a single polar flagellum, like other yellow pigment-producing pseudomonads related to them. Both strains produced catalase and oxidase. Similar to P. straminea, they did not hydrolyse gelatin or casein. The G+C DNA contents determined were 57.5 mol% for CH01(T) and 58.0 mol% for PA01. DNA-DNA hybridization results showed 81 % relatedness between them, and only 40-44 % relatedness with respect to the type strain of P. straminea. These results, together with other phenotypic characteristics, support the conclusion that both isolates belong to the same species, and should be described as representing a novel species within the genus Pseudomonas, for which the name Pseudomonas argentinensis sp. nov. is proposed. The type strain is CH01(T) (=LMG 22563(T) = CECT 7010(T)).

  15. Lead tolerance capacity of clinical bacterial isolates and change in their antibiotic susceptibility pattern after exposure to a heavy metal

    Directory of Open Access Journals (Sweden)

    Divya Garhwal

    2014-07-01

    Full Text Available Introduction: Heavy metal pollutions of soil and wastewater are a significant environmental problem as they are not degraded or destroyed. Several metal resistance mechanisms have been identified which is responsible for alteration of normal cell physiology leading to development of drug resistance in microorganisms. Heavy metals used in industry and in household products are, along with antibiotics, creating a selective pressure in the environment that leads to the mutations in microorganisms. The present study was carried out to study the heavy metal lead tolerance by bacteria and change in antibiotic-sensitivity pattern after its exposure. Materials and Methods: 30 clinical isolates from various samples received in the Department of Microbiology, Government Medical College, Surat, were included in the study. To check the lead tolerance capacity, isolates were exposed to graded concentration of lead nitrate by plate dilution method, starting from 50 up to 1000 μg/ml strength. Antibiotic susceptibility was performed by the Kirby Bauer disc diffusion method. A change in antibiotic susceptibility pattern was studied before and after lead exposure. Result: 30 clinical isolates were included in the study, 25 Gram negative (83.3% and 5 Gram positive (16.7%. MIC to lead was higher in Acinetobacter spp. and Pseudomonas spp. (600-1000 μg/ml as compared to E. coli, Klebsiella spp., S. aureus (50-150 μg/ml. Multiple antibiotic resistance indexes were changed significantly after lead exposure. Conclusion: Bacteria exposed to high levels of heavy metals in their environment have adapted to this stress by developing various resistance mechanism. Infection with antibiotic-resistant organisms create problem in treatment and management of patients. We should take efforts to prevent environmental pollution with such heavy metals and transmission of antibiotic-resistant microorganism from environment to health care set up.

  16. Microcystin-degrading activity of an indigenous bacterial strain Stenotrophomonas acidaminiphila MC-LTH2 isolated from Lake Taihu.

    Directory of Open Access Journals (Sweden)

    Fei Yang

    Full Text Available Microcystin-LR (MC-LR and microcystin-RR (MC-RR produced by harmful cyanobacterial blooms (HCBs pose substantial threats to the ecosystem and public health due to their potential hepatotoxicity. Degradation of microcystins (MCs by indigenous bacteria represents a promising method for removing MCs from fresh water without harming the aquatic environment, but only a few microcystin (MC-degrading bacteria have been isolated and had their mechanisms reported. This study aimed to isolate indigenous bacteria from Lake Taihu, and investigate the capability and mechanism of MC degradation by these bacteria. During a Microcystis bloom, an indigenous MC-degrading bacterium designated MC-LTH2 was successfully isolated from Lake Taihu, and identified as Stenotrophomonas acidaminiphila based on phylogenetic analysis. In the presence of MC-LR together with MC-RR, the strain MC-LTH2 was capable of totally degrading both simultaneously in 8 days, at rates of 3.0 mg/(L⋅d and 5.6 mg/(L⋅d, respectively. The degradation rates of MCs were dependent on temperature, pH, and initial MC concentration. Adda (3-amino-9-methoxy-2, 6, 8-trimethyl-10-phenyldeca-4, 6-dienoic acid was detected as an intermediate degradation product of MCs using high performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF-MS. To the best of our knowledge, this is the first report of Stenotrophomonas acidaminiphila capable of degrading two MC analogues and other compounds containing Adda residue completely under various conditions, although the mlrA gene in the strain was not detected. These results indicate the Stenotrophomonas acidaminiphila strain MC-LTH2 possesses a significant potential to be used in bioremediation of water bodies contaminated by MC-LR and MC-RR, and is potentially involved in the degradation of MCs during the disappearance of the HCBs in Lake Taihu.

  17. Characterisation of the bacterial microbiota of the vagina of dairy cows and isolation of pediocin-producing Pediococcus acidilactici.

    Science.gov (United States)

    Wang, Yvonne; Ametaj, Burim N; Ambrose, Divakar J; Gänzle, Michael G

    2013-01-29

    Uterine infections in dairy cows lower profitability of dairy operations. Infections of the reproductive tract are related to the overgrowth of pathogenic bacteria during the first three weeks after parturition. However, alterations in the vaginal microbiota composition in the first weeks after parturition remain poorly documented. In this study, bacteria isolated from the vagina of healthy pregnant, and infected postpartum cows were characterised by random amplification of polymorphic DNA (RAPD) analysis and partial 16S ribosomal RNA (rDNA) gene sequencing. Populations of bacilli and lactic acid bacteria of the genera Enterococcus, Lactobacillus, and Pediococcus were present in both healthy and infected cows. Infected cows had a significant increase in the vaginal enteric bacteria population which consisted mainly of Escherichia coli. Three E. coli isolates harboured the gene coding for Shiga-like-toxin (SLT) I or II. Several isolates of the Pediococcus acidilactici were found to produce the bacteriocin pediocin AcH/PA-1. Quantitative PCR analyses of vaginal mucus samples collected from ten metritic cows before and after parturition confirmed the presence of the Lactobacillus group (Lactobacillus spp., Pediococcus spp., Leuconostoc spp., and Weissella spp.); Enterobacteriaceae, E. coli, and bacilli. The presence of the pediocin AcH/PA-1 structural gene and SLT genes were also confirmed with qPCR. In conclusion, overgrowth of pathogenic bacteria, particularly E. coli, after parturition likely contributes to the development of metritis. Our microbiota analysis extends the information related to the composition of commensal bacteria in the bovine female reproductive tract and may facilitate the development of novel intervention strategies for prevention of uterine infections in dairy cows.

  18. Characterisation of the bacterial microbiota of the vagina of dairy cows and isolation of pediocin-producing Pediococcus acidilactici

    Directory of Open Access Journals (Sweden)

    Wang Yvonne

    2013-01-01

    Full Text Available Abstract Background Uterine infections in dairy cows lower profitability of dairy operations. Infections of the reproductive tract are related to the overgrowth of pathogenic bacteria during the first three weeks after parturition. However, alterations in the vaginal microbiota composition in the first weeks after parturition remain poorly documented. Results In this study, bacteria isolated from the vagina of healthy pregnant, and infected postpartum cows were characterised by random amplification of polymorphic DNA (RAPD analysis and partial 16S ribosomal RNA (rDNA gene sequencing. Populations of bacilli and lactic acid bacteria of the genera Enterococcus, Lactobacillus, and Pediococcus were present in both healthy and infected cows. Infected cows had a significant increase in the vaginal enteric bacteria population which consisted mainly of Escherichia coli. Three E. coli isolates harboured the gene coding for Shiga-like-toxin (SLT I or II. Several isolates of the Pediococcus acidilactici were found to produce the bacteriocin pediocin AcH/PA-1. Quantitative PCR analyses of vaginal mucus samples collected from ten metritic cows before and after parturition confirmed the presence of the Lactobacillus group (Lactobacillus spp., Pediococcus spp., Leuconostoc spp., and Weissella spp.; Enterobacteriaceae, E. coli, and bacilli. The presence of the pediocin AcH/PA-1 structural gene and SLT genes were also confirmed with qPCR. Conclusions In conclusion, overgrowth of pathogenic bacteria, particularly E. coli, after parturition likely contributes to the development of metritis. Our microbiota analysis extends the information related to the composition of commensal bacteria in the bovine female reproductive tract and may facilitate the development of novel intervention strategies for prevention of uterine infections in dairy cows.

  19. Isolation of bacterial strains able to degrade biphenyl, diphenyl ether and the heat transfer fluid used in thermo-solar plants.

    Science.gov (United States)

    Blanco-Moreno, Rafael; Sáez, Lara P; Luque-Almagro, Víctor M; Roldán, M Dolores; Moreno-Vivián, Conrado

    2017-03-25

    Thermo-solar plants use eutectic mixtures of diphenyl ether (DE) and biphenyl (BP) as heat transfer fluid (HTF). Potential losses of HTF may contaminate soils and bioremediation is an attractive tool for its treatment. DE- or BP-degrading bacteria are known, but up to now bacteria able to degrade HTF mixture have not been described. Here, five bacterial strains which are able to grow with HTF or its separate components DE and BP as sole carbon sources have been isolated, either from soils exposed to HTF or from rhizospheric soils of plants growing near a thermo-solar plant. The organisms were identified by 16S rRNA gene sequencing as Achromobacter piechaudii strain BioC1, Pseudomonas plecoglossicida strain 6.1, Pseudomonas aeruginosa strains HBD1 and HBD3, and Pseudomonas oleovorans strain HBD2. Activity of 2,3-dihydroxybiphenyl dioxygenase (BphC), a key enzyme of the biphenyl upper degradation pathway, was detected in all isolates. Pseudomonas strains almost completely degraded 2000ppm HTF after 5-day culture, and even tolerated and grew in the presence of 150,000ppm HTF, being suitable candidates for in situ soil bioremediation. Degradation of both components of HTF is of particular interest since in the DE-degrader Sphingomonas sp. SS3, growth on DE or benzoate was strongly inhibited by addition of BP.

  20. Enhancing the Decolorizing and Degradation Ability of Bacterial Consortium Isolated from Textile Effluent Affected Area and Its Application on Seed Germination

    Directory of Open Access Journals (Sweden)

    Rashid Mahmood

    2015-01-01

    Full Text Available A bacterial consortium BMP1/SDSC/01 consisting of six isolates was isolated from textile effected soil, sludge, and textile effluent from Hudiara drain near Nishat Mills Limited, Ferozepur Road, Lahore, Pakistan. It was selected because of being capable of degrading and detoxifying red, green, black, and yellow textile dyes. The pH and supplements were optimized to enhance the decolorization ability of the selected consortium. The results indicated that decolorizing ability of consortium for the red, green, black, and yellow dyes was higher as compared to individual strains. The consortium was able to decolorize 84%, 84%, 85%, 85%, and 82% of 200 ppm of red, green, black, yellow, and mixed dyes within 24 h while individual strain required 72 h. On supplementing urea, the consortium decolorized 87, 86, 89, 86, and 83%, respectively, while on supplementing sodium chloride the consortium decolorized 93, 94, 93, 94, and 89% of red, green, black, yellow, and mixed dyes, respectively, which was maximum while in the presence of ascorbic acid and ammonium chloride it showed intermediate results. The effect of untreated and treated dyes was investigated on Zea mays L. (maize and Sorghum vulgare Pers. (sorghum. This study will help to promote an efficient biotreatment of textile effluents.

  1. [Evaluation of mixed biofilm formation between Candida albicans and a variety of bacterial species isolated from peripheral catheters at Tlemcen CHU. First study in Algeria].

    Science.gov (United States)

    Seghir, A; Boucherit-Otmani, Z; Boucherit, K; Sari-Belkharroubi, L; Anselme-Bertrand, I

    2015-06-01

    Mixed-species biofilms constitute a reservoir of infection for a group of bacteria and yeasts that coexist on the same support. Peripheral venous catheters make up a good surface for the attachment of microorganisms that promote biofilm formation and this requires complex strategies for antimicrobial treatments. No such studies on formation mixed biofilms have ever been conducted in Algeria. Therefore, we evaluated the potential for the formation of mixed-species biofilms by Candida albicans and some bacterial species isolated from peripheral vascular catheters at the University Hospital of Tlemcen, in Algeria. The results obtained showed that C. albicans have the potential to form mixed biofilms with three bacteria (Enterobacter cloacae, Bordetella spp. and Serratia liquefaciens) isolated from the same catheter as the yeasts. The amount of biofilms produced varies depending on the species and the composition of the growth medium. Observations by scanning electron microscopy showed that the structure of the mixed biofilm depends on the surface support the biofilm was formed on, and varies with the species. A competition was noted between bacteria and yeasts; it depends on the composition of the medium and its pH, which both play an important role in promoting the dominance of one over the other. Copyright © 2015. Published by Elsevier Masson SAS.

  2. Isolation and characterization of Acidithiobacillus caldus from a sulfur-oxidizing bacterial biosensor and its role in detection of toxic chemicals.

    Science.gov (United States)

    Hassan, Sedky H A; Van Ginkel, Steven W; Kim, Sung-Min; Yoon, Sung-Hwan; Joo, Jin-Ho; Shin, Beom-Soo; Jeon, Byong-Hun; Bae, Wookeun; Oh, Sang-Eun

    2010-08-01

    A novel toxicity detection methodology based on sulfur-oxidizing bacteria (SOB) has been developed for the rapid and reliable detection of toxic chemicals in water. The methodology exploits the ability of SOB to oxidize sulfur particles in the presence of oxygen to produce sulfuric acid. The reaction results in an increase in electrical conductivity (EC) and a decrease in pH. The assay is based on the inhibition of SOB in the presence of toxic chemicals by measuring changes in EC and pH. We found that SOB biosensor can detect toxic chemicals, such as heavy metals and CN-, in the 5-2000ppb range. One bacterium was isolated from an SOB biosensor and the 16S rRNA gene of the bacterial strain has 99% and 96% sequence similarity to Acidithiobacillus sp. ORCS6 and Acidithiobacillus caldus DSM 8584, respectively. The isolate was identified as A. caldus SMK. The SOB biosensor is ideally suited for monitoring toxic chemicals in water having the advantages of high sensitivity and quick detection.

  3. Differential induction of innate defense antimicrobial peptides in primary nasal epithelial cells upon stimulation with inflammatory cytokines, Th17 cytokines or bacterial conditioned medium from Staphylococcus aureus isolates.

    Science.gov (United States)

    Burgey, Christine; Kern, Winfried V; Römer, Winfried; Rieg, Siegbert

    2016-01-01

    To date it is incompletely understood why half of the human population is intrinsically resistant to Staphylococcus aureus colonization whereas the other half is intermittently or permanently colonized. Nasal colonization represents the primary niche for S. aureus. We therefore investigated whether primary nasal epithelial cells (HNEC) express antimicrobial peptides (AMPs) upon stimulation by inflammatory cytokines or bacterial conditioned medium (BCM) of different colonizing and invasive staphylococci. Stimulation with classical cytokines (IL-1β, TNF-α, IFN-γ) potently induced hBD-3 and RNase7 in HNEC. Th17 cytokines (IL-17A, IL-17F, IL-22) yielded comparably weak hBD-3 and RNase7 induction and no synergistic effects with classical cytokines. BCM of S. aureus and Staphylococcus epidermidis isolates moderately induced hBD3 and RNase7 mRNA expression without significant differences when comparing colonizing vs. invasive isolates. Our results indicate that HNEC contribute to the innate defense by secretion of an AMP-containing chemical defense shield along the nasal mucosa i.e. within the primary colonization niche of S. aureus. Further studies are needed to investigate whether a deficient AMP expression in the nasal mucosa may be related to different S. aureus carrier states. AMPs or AMP-inducing agents may be promising candidates for future topical decolonization regimens that aim to prevent invasive S. aureus infections.

  4. Synergistic Effects of n-Hexane Fraction of Parkia biglobosa (Jacq. Bark Extract and Selected Antibiotics on Bacterial Isolates

    Directory of Open Access Journals (Sweden)

    Oluwatayo E. Abioye

    2017-02-01

    Full Text Available The incidence of resistance to commonly used antimicrobial agents by microbial pathogens demands increased effort in the development of effective ways of treating infections and diseases. The n-hexane fraction of lyophilized crude bark extract of Parkia biglobosa (Jacq. was prepared and, in combination with selected antibiotics, assayed for antimicrobial activity against some selected bacterial pathogens using time-kill assay. Protein leakage analysis of the combined agents was performed using Bradford protein quantification method. Determination of active compounds present in the n-hexane fraction was done using Fourier Transform Infrared Spectroscopy (FTIR. While time-kill assay detected 43.33% synergy; 56.67% indifference and no antagonism at 1/2 × minimum inhibitory concentration (MIC, 1 × MIC exhibited 55% synergy, 45% indifference and no antagonism. Protein leakages from the cells of selected bacteria ranged from 1.20 µg/mL to 256.93 µg/mL. The presence of a phenyl group, an aromatic ring and phenolic compounds in the n-hexane fraction was confirmed at 2162 cm−1–2020 cm−1, 1605 cm−1–1533 cm−1 and 1438 cm−1–1444 cm−1 spectra peaks, respectively. The observed antibiotic−n-hexane fraction synergistic interaction revealed the improved antibacterial activity of the selected antibiotics. Hence, exploration of a combination of antibiotics with plant secondary metabolites is hereby advocated in the global quest for means of combating infectious diseases caused by multidrug-resistant pathogens.

  5. s-triazine degrading bacterial isolate Arthrobacter sp. AK-YN10, a candidate for bioaugmentation of atrazine contaminated soil.

    Science.gov (United States)

    Sagarkar, Sneha; Bhardwaj, Pooja; Storck, Veronika; Devers-Lamrani, Marion; Martin-Laurent, Fabrice; Kapley, Atya

    2016-01-01

    The Arthrobacter sp. strain AK-YN10 is an s-triazine pesticide degrading bacterium isolated from a sugarcane field in Central India with history of repeated atrazine use. AK-YN10 was shown to degrade 99 % of atrazine in 30 h from media supplemented with 1000 mg L(-1) of the herbicide. Draft genome sequencing revealed similarity to pAO1, TC1, and TC2 catabolic plasmids of the Arthrobacter taxon. Plasmid profiling analyses revealed the presence of four catabolic plasmids. The trzN, atzB, and atzC atrazine-degrading genes were located on a plasmid of approximately 113 kb.The flagellar operon found in the AK-YN10 draft genome suggests motility, an interesting trait for a bioremediation agent, and was homologous to that of Arthrobacter chlorophenolicus. The multiple s-triazines degradation property of this isolate makes it a good candidate for bioremediation of soils contaminated by s-triazine pesticides.

  6. The Antibiotic Resistance Profiles of Bacterial Strains Isolated from Patients with Hospital-Acquired Bloodstream and Urinary Tract Infections

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    Hamed Ghadiri

    2012-01-01

    Full Text Available Treatment of nosocomial infections is becoming difficult due to the increasing trend of antibiotics resistance. Current knowledge on antibiotic resistance pattern is essential for appropriate therapy. We aimed to evaluate antibiotic resistance profiles in nosocomial bloodstream and urinary tract pathogens. A total of 129 blood stream and 300 urinary tract positive samples were obtained from patients referring to Besat hospital over a two-year period (2009 and 2010. Antibiotic sensitivity was ascertained using the Kirby-Bauer disk diffusion technique according to CLSI guidelines. Patient's data such as gender and age were recorded. The ratio of gram-negative to gram-positive bacteria in BSIs was 1.6 : 1. The most prevalent BSI pathogen was Coagulase-Negative Staphylococci (CoNS. The highest resistance rate of CoNS was against penicillin (91.1% followed by ampicillin (75.6%, and the lowest rate was against vancomycin (4.4%. Escherichia coli was the most prevalent pathogen isolated from urinary tract infections (UTIs. Ratio of gram-negative to gram-positive bacteria was 3.2 : 1. The highest resistance rate of E. coli isolates was against nalidixic acid (57.7%. The present study showed that CoNS and E. coli are the most common causative agents of nosocomial BSIs and UTIs, and control of infection needs to be addressed in both antibiotic prescription and general hygiene.

  7. Calcium Carbonate Precipitation by Bacillus and Sporosarcina Strains Isolated from Concrete and Analysis of the Bacterial Community of Concrete.

    Science.gov (United States)

    Kim, Hyun Jung; Eom, Hyo Jung; Park, Chulwoo; Jung, Jaejoon; Shin, Bora; Kim, Wook; Chung, Namhyun; Choi, In-Geol; Park, Woojun

    2016-03-01

    Microbially induced calcium carbonate precipitation (CCP) is a long-standing but re-emerging environmental engineering process for production of self-healing concrete, bioremediation, and long-term storage of CO2. CCP-capable bacteria, two Bacillus strains (JH3 and JH7) and one Sporosarcina strain (HYO08), were isolated from two samples of concrete and characterized phylogenetically. Calcium carbonate crystals precipitated by the three strains were morphologically distinct according to field emission scanning electron microscopy. Energy dispersive X-ray spectrometry mapping confirmed biomineralization via extracellular calcium carbonate production. The three strains differed in their physiological characteristics: growth at alkali pH and high NaCl concentrations, and urease activity. Sporosarcina sp. HYO08 and Bacillus sp. JH7 were more alkali- and halotolerant, respectively. Analysis of the community from the same concrete samples using barcoded pyrosequencing revealed that the relative abundance of Bacillus and Sporosarcina species was low, which indicated low culturability of other dominant bacteria. This study suggests that calcium carbonate crystals with different properties can be produced by various CCP-capable strains, and other novel isolates await discovery.

  8. Bioremediation of polycyclic aromatic hydrocarbon (PAH) compounds: (acenaphthene and fluorene) in water using indigenous bacterial species isolated from the Diep and Plankenburg rivers, Western Cape, South Africa.

    Science.gov (United States)

    Alegbeleye, Oluwadara Oluwaseun; Opeolu, Beatrice Olutoyin; Jackson, Vanessa

    2016-11-24

    This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25°C, 30°C, 35°C, 37°C, 38°C, 40°C and 45°C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37°C, 37°C, 30°C and 35°C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems.

  9. Bacterial isolates and drug susceptibility patterns of urinary tract infection among pregnant women at Muhimbili National Hospital in Tanzania.

    Science.gov (United States)

    Moyo, Sabrina J; Aboud, Said; Kasubi, Mabula; Maselle, Samuel Y

    2010-10-01

    Urinary tract infection (UTI) during pregnancy may cause complications such as pyelonephritis, hypertensive disease of pregnancy, anaemia, chronic renal failure, premature delivery and foetal mortality. This study aimed to identify the etiologic agents of UTI and to determine the patterns of antimicrobial drug susceptibility among pregnant women at Muhimbili National Hospital in Tanzania. Retrospective analysis of 200 mid-stream urine specimens processed for culture and antimicrobial drug susceptibility testing between January 2007 and December 2009 was carried out. Significant bacteriuria (> 105 colony forming units/mL of urine) was found in 42/200 (21%) specimens. Of the 42 isolates, the most commonly isolated bacteria were Escherichia coli 14 (33.3%), Klebsiella spp 9 (21.4%) coagulase negative Staphylococcus 7 (16.7%), Staphylococcus aureus 6 (14.3%), Proteus species 3 (7.1%) and Enterococcus species 3 (7.1%). Low rate to moderately high rate of antimicrobial drug resistance was observed against first line drugs namely, nitrofurantoin 18.7 % (n=16), co-trimoxazole 38.5 % (n=13) and ampicillin 57.7% (n=26). Relatively low rate of resistance was seen against second line drugs: ciprofloxacin 13.6 % (n=22) and amikacin 5 % (n=20). High rate of resistance was observed in third generation cephalosporin cefotaxime 31.2 % (n=16). Of the Gram-positive organisms tested against vancomicin and methicilin, resistance was found in 25 % (n=13) and 25 % (n=4), respectively. In conclusion, E coli was found to be the common cause of UTI among the pregnant women. Low to moderately high level of resistance was found in first line drugs while high level of resistance was found in third generation cephalosporin. It is recommended to monitor the levels of resistance for nitrofurantoin, fluoroquinolone and cefotaxime and to screen for Extended Spectrum Beta Lactamase production among cefotaxime resistant E. coli and Klebsiella spp.

  10. Isolation of anaerobic bacterial strains from cellulolytic bacterial com- munity WSC-9%纤维素分解复合菌系WSC-9中厌氧细菌的分离

    Institute of Scientific and Technical Information of China (English)

    温雪; 付博锐; 王彦杰; 高亚梅; 刘权; 晏磊; 王伟东

    2013-01-01

    The microbial community WSC-9 capable of degrading lignocellulose with high efficiency was enriched from composting of cattle manure and rice straw. The aims of this study were to isolate and identify the anaerobic bacterial strains from the cellulose-degrading bacterial community. An anaerobic, thermophilic and cellulolytic bacterium was isolated, which was named WSC-9-7. More than 47% of rice straw was degraded within 10 days of inoculation at 50 ° C by WSC-9-7. WSC-9-7 is a spore-forming and straight rod. Cellobiose, cellulose, filter paper and rice straw can be utilized as sole carbon and energy sources by WSC-9-7 in medium. On the basis of 16S rDNA gene sequence similarity, WSC-9-7 was mapped to the genus Clostridium. It is closely related to HAW-RM37-2-B-1600d-W (99%), and Clostridium islandicum AK1(98%). Clostridium islandicum AK1 was a new anaerobic, saccharolytic, thermophilic bacterium, isolated from hot spring in Iceland. HAW-RM37-2-B-1600d-W was uncultured clone from compost environmental samples. All of them were thermophilic and anaerobic bacterium. Hence, WSC-9-7 represents a novel species is proposed.%  复合菌系WSC-9是一组具高效稳定分解纤维素能力的细菌复合群体.为了研究其微生物组成,以纤维素分解情况为依据,分离复合菌系中具有纤维素分解能力的厌氧纯培养菌株,通过16S rDNA基因序列初步分析确定系统发育地位.从WSC-9中获得1株可有效降解纤维素的严格厌氧细菌WSC-9-7,50℃培养10 d,稻秆的总干重减少了47%.WSC-9-7为杆菌,产孢,能够利用纤维二糖、纤维素、滤纸、稻秆等.经数据库比对,与菌株HAW-RM37-2-B-1600d-W(FN563295)的相似性达到99%,与Clostridium islandicum AK1(EF088328)的相似性为98%.其中,Clostridium islandicum AK1厌氧且可以分解多糖类物质,获于冰岛的热泉;HAW-RM37-2-B-1600d-W在堆肥样品的克隆结果中获得,未获得纯培养.菌株WSC-9-7与这两株细菌均为嗜高温的严格

  11. Microbiota anaeróbia isolada de bovinos com pododermatite Anaerobic bacterial species isolated from bovines with pododermatitis

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    C.A. Silva

    1999-06-01

    Full Text Available O presente trabalho teve como objetivo isolar e identificar espécies bacterianas anaeróbias presentes nos pés de bovinos portadores de vários graus de pododermatite. Foram utilizados 60 bovinos, distribuídos em quatro grupos de 15. O grupo I foi constituído por animais saudáveis e serviu de controle; o grupo II, por bovinos na fase inicial do processo; o grupo III, por animais portadores de pododermatite interdigital vegetativa e o grupo IV, por bovinos portadores de pododermatite necrosante. Foram colhidos fragmentos de tecido interdigital para cultura e as principais espécies bacterianas isoladas foram: Dichelobacter nodosus nos grupos II, III e IV e Fusobacterium necrophorum nos grupos III e IV, com freqüências de 26,7%, 6,7%, 20,0%, 6,7% e de 13,3%, respectivamente. Encontraram-se também Fusobacterium symbiosum em 40,0% no gb>rupo I, 6,7% no grupo II, 13,3% no grupo III e 13,3% no grupo IV, Bacteroides sp. em 6,7% nos grupos I e IV, Bacteroides ruminatus em 33,3% no grupo I, 6,7% no grupo II, 33,3% no grupo III e 13,3% no grupo IV, Bacteroides oralis em 6,7% no grupo III e Fusobacterium mortiferum em 6,7% no grupo IV.The objective of this study was to isolate and identify the anaerobic bacteria species in bovine with different degrees of pododermatitis. Sixty bovines were divided into four groups of 15 as follows: group I included healthy animals, used as control; group II with animals in the initial phase of the process; group III, with animals displaying interdigital skin hyperplasia and group IV with animals with footrot. Interdigital tissue fragments were collected and processed for isolation and identification of anaerobic agents. The bacteria species isolated were: Dichelobacter nodosus in groups II, III and IV and Fusobacterium necrophorum only in groups III and IV, with frequencies of 26.7%, 6.7%, and 20.0% for the former and 6.7% and 13.3% for the latter, respectively. In addition, Fusobacterium symbiosum was present in

  12. Optimization of Endoglucanase Production from a Novel Bacterial Isolate, Arthrobacter sp. HPG166 and Characterization of Its Properties

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    Shengwei Huang

    2015-10-01

    Full Text Available ABSTRACTIn this study, a potential novel cellulolytic bacteriumArthrobacter sp. HPG166 was isolated from the hindgut of root-feeding larvaeHolotrichia parallela. Optimization of fermentation factors for endoglucanase production byArthrobacter sp. HPG166 was carried out via response surface methodology. Sodium carboxymethylcellulose 1.19% (w/v and beef extract 0.35% (w/v were the ideal combination of carbon and nitrogen sources for enzyme production; the optimum temperature and pH for cellulase production were 34°C and pH 8.0 respectively. Under the optimized fermentation conditions, the maximum endoglucanase activity of 1.411 U mL-1 was obtained. The crude endoglucanase was thermotolerant as it retained 50.31% of its activity after incubation at 70°C for an hour. Metal profile of the enzyme indicated that Mg2+ and Na+ were strong stimulators while Mn2+ and Co+ drastically inhibited its activity. Due to its particular characteristics, this enzyme could have potential for industrial applications.

  13. Isolation of a bacterial strain, Acinetobacter sp. from centrate wastewater and study of its cooperation with algae in nutrients removal.

    Science.gov (United States)

    Liu, Hui; Lu, Qian; Wang, Qin; Liu, Wen; Wei, Qian; Ren, Hongyan; Ming, Caibing; Min, Min; Chen, Paul; Ruan, Roger

    2017-07-01

    Algae were able to grow healthy on bacteria-containing centrate wastewater in a pilot-scale bioreactor. The batch experiment indicated that the co-cultivation of algae and wastewater-borne bacteria improved the removal efficiencies of chemical oxygen demand and total phosphorus in centrate wastewater to 93.01% and 98.78%, respectively. A strain of beneficial aerobic bacteria, Acinetobacter sp., was isolated and its biochemical characteristics were explored. Synergistic cooperation was observed in the growth of algae and Acinetobacter sp. Removal efficiencies of some nutrients were improved significantly by the co-cultivation of algae and Acinetobacter sp. After treatment, residual nutrients in centrate wastewater reached the permissible discharge limit. The cooperation between algae and Acinetobacter sp. was in part attributed to the exchange of carbon dioxide and oxygen between the algae and bacteria. This synergetic relationship between algae and Acinetobacter sp. provided a promising way to treat the wastewater by improving the nutrients removal and biomass production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Beta-lactam effects on mixed cultures of common respiratory isolates as an approach to treatment effects on nasopharyngeal bacterial population dynamics.

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    David Sevillano

    Full Text Available BACKGROUND: Streptococcus pneumoniae, Streptococcus pyogenes and Haemophilus influenzae are bacteria present in the nasopharynx as part of normal flora. The ecological equilibrium in the nasopharynx can be disrupted by the presence of antibiotics. METHODOLOGY/PRINCIPAL FINDINGS: A computerized two-compartment pharmacodynamic model was used to explore beta-lactam effects on the evolution over time of a bacterial load containing common pharyngeal isolates by simulating free serum concentrations obtained with amoxicillin (AMX 875 mg tid, amoxicillin/clavulanic acid (AMC 875/125 mg tid and cefditoren (CDN 400 mg bid regimens over 24 h. Strains and MICs (microg/ml of AMX, AMC and CDN were: S. pyogenes (0.03, 0.03 and 0.015, S. pneumoniae (2, 2 and 0.25, a beta-lactamase positive H. influenzae (BL(+; >16, 2 and 0.06 and a beta-lactamase positive AMC-resistant H. influenzae (BLPACR, >16, 8 and 0.06. Mixture of identical 1:1:1:1 volumes of each bacterial suspension were prepared yielding an inocula of approximately 4 x 10(6 cfu/ml. Antibiotic concentrations were measured both in bacterial and in bacteria-free antibiotic simulations. beta-lactamase production decreased AMX concentrations and fT(>MIC against S. pneumoniae (from 43.2% to 17.7% or S. pyogenes (from 99.9% to 24.9%, and eradication was precluded. The presence of clavulanic acid countered this effect of co-pathogenicity, and S. pyogenes (but not BL(+ and S. pneumoniae was eradicated. Resistance of CDN to TEM beta-lactamase avoided this co-pathogenicity effect, and CDN eradicated S. pyogenes and H. influenzae strains (fT(>MIC >58%, and reduced in 94% S. pneumoniae counts (fT(>MIC approximately 25%. CONCLUSIONS/SIGNIFICANCE: Co-pathogenicity seems to be gradual since clavulanic acid countered this effect for strains very susceptible to AMX as S. pyogenes but not for strains with AMX MIC values in the limit of susceptibility as S. pneumoniae. There is a potential therapeutic advantage for beta

  15. Antibiotic resistance of bacterial isolates from aquatic animals and its prevention and control%水产动物源细菌耐药性与预防控制

    Institute of Scientific and Technical Information of China (English)

    李国烈; 李林桂; 房文红

    2012-01-01

    Bacterial resistance is the ability of a disease-causing bacterium to resist being killed by antibiotics. The formation of bacterial resistance is the result of the development of bacterial evolution and the manifest of bacterial adaptability; however, it threatens the development of aquaculture and human health. Firstly, this paper summarized the research progress on the bacterial resistance in aquatic animals in recent years, including plasmid-mediated resistance of bacteria, resistance gene of bacterial isolates from aquatic animals, and the genetic mechanism of antibiotic resistance and so on. Secondly, the paper analyzed the harm of bacterial resistance, which included the pathogen of bacterial resistance that caused epidemics and the antibiotic resistance of bacterial isolates from aquatic animals that threatened public health. Finally, from rational and standardized use of drugs, speeding up the development and application of aquatic vaccines and new antimicrobial drugs alternatives, strengthening of the surveillance about pathogen isolates from aquatic animals and so on, the paper provided some valuable methods and strategies on the prevention and control for bacterial resistance in aquatic animals.%细菌耐药性是指细菌对于抗菌药物作用的耐受性。细菌耐药性的形成,是细菌进化发展的结果,是细菌适应性的表现,但它却给养殖业的发展和人类的健康带来威胁。本文首先综述了水产动物源细菌耐药性研究现状,主要包括质粒介导的水产动物源细菌耐药性、细菌耐药基因、细菌耐药性遗传学机制等;其次,从病原菌耐药性会导致水产疾病流行爆发和水产细菌耐药性对人类公共卫生安全的影响两方面,分析了水产动物源细菌耐药性的危害;最后,从合理、规范用药,加快水产疫苗和新型抗菌药物替代品的研制与应用,加强水产动物致病菌耐药性监测等方面,提出了预防和控制

  16. Honey bees avoid nectar colonized by three bacterial species, but not by a yeast species, isolated from the bee gut.

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    Ashley P Good

    Full Text Available The gut microflora of the honey bee, Apis mellifera, is receiving increasing attention as a potential determinant of the bees' health and their efficacy as pollinators. Studies have focused primarily on the microbial taxa that appear numerically dominant in the bee gut, with the assumption that the dominant status suggests their potential importance to the bees' health. However, numerically minor taxa might also influence the bees' efficacy as pollinators, particularly if they are not only present in the gut, but also capable of growing in floral nectar and altering its chemical properties. Nonetheless, it is not well understood whether honey bees have any feeding preference for or against nectar colonized by specific microbial species. To test whether bees exhibit a preference, we conducted a series of field experiments at an apiary using synthetic nectar inoculated with specific species of bacteria or yeast that had been isolated from the bee gut, but are considered minor components of the gut microflora. These species had also been found in floral nectar. Our results indicated that honey bees avoided nectar colonized by the bacteria Asaia astilbes, Erwinia tasmaniensis, and Lactobacillus kunkeei, whereas the yeast Metschnikowia reukaufii did not affect the feeding preference of the insects. Our results also indicated that avoidance of bacteria-colonized nectar was caused not by the presence of the bacteria per se, but by the chemical changes to nectar made by the bacteria. These findings suggest that gut microbes may not only affect the bees' health as symbionts, but that some of the microbes may possibly affect the efficacy of A. mellifera as pollinators by altering nectar chemistry and influencing their foraging behavior.

  17. Isolation and Identification of an Indigenous Probiotic Lactobacillus Strain: Its Encapsulation with Natural Branched Polysaccharids to Improve Bacterial Viability

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    Nafiseh Sadat Foroutan

    2017-06-01

    Full Text Available Background and Objective: Probiotics have to reach their site of action in certain numbers in order to exhibit positive health effects. Encapsulation has shown remarkable enhancing effects on probiotic survival in simulated gastric conditions compared to free bacteria. The purpose of this study was identification and evaluation of a potential probiotic strain using encapsulation process by new carriers in order to improve probiotic viability during in vitro simulated conditions.Material and Methods: A native Lactobacillus was isolated from yogurt, identified as Lactobacillus casei PM01 (NCBI registered and analyzed for probiotic properties alongside established probiotic strains of Lactobacillus acidophilus ATCC 43556, and Lactobacillus rhamnosus ATCC 7469. Acid and bile resistance, adhesion to Caco-2 cells and antibiotic resistance were evaluated. Lactobacillus casei PM01 was encapsulated with alginate, chitosan and natural branched polysaccharides (pectin, tragacanth gum and gum Arabic by using extrusion technique. Encapsulation efficiency, acidification activity and viability of entrapped Lactobacillus casei PM01 in simulated gastric pH were determined. Results and Conclusion: Based on the results, all the three strains could be considered as potential probiotics, and are good candidates for further in vitro and in vivo evaluation. The results showed that the survival of encapsulated Lactobacillus casei PM01 was significantly (p≤0.05 increased when it was incubated in simulated gastric pH. It can be concluded that indigenous Lactobacillus casei PM01 in encapsulated form is introduced as an efficient probiotic strain for using in dairy products.Conflict of interest: The authors declare no conflict of interest.

  18. Isolation of a Siderophore-Producting Bacterial Strain and Mica-bacterial Interactions%一株产铁载体细菌的筛选及其与云母的相互作用

    Institute of Scientific and Technical Information of China (English)

    何琳燕; 张垠; 盛下放; 黄智

    2012-01-01

    Studies on the interactions between siderophore-producting bacteria and mica minerals will help us understand the mechanism of bio-weathering, the formation of soil, global cycle of several elements, and local environmental contamination. A siderophore(pyoverdins)-producting bacterial strain Z6 was isolated from rhizosphere soil of advantage wild plants sheep sorrel (Rumex acetosa L.) growing in Longshan potassium mine tailings in Nanjing, which was identified as Pseudomonas sp. By checking the individual morphology, colony characteristics, and 16S rDNA sequencing. Using the test cultures containing biotite or muscovite inoculated with Pseudomonas sp. Z6, we found that a strong increase in the amount of siderophore in the fiest 15 days and bacteria could influence silicon and iron mobilization from mica minerals consistently until 75 d of culture. The amounts of iron released from biotite in the presence of Z6 increased by 211 times and the silicon increased by a factor of 27.8, much higher than that in the negative control without minerals. SEM analysis revealed the formation of erosion and bacteria-mineral aggregates on the surface of mica. Cellular growth, siderophere production and pH change by Pseudomonas sp. Z6 cultivated in biotite were directly and quickly influenced, more significantly than that in muscovite experimental setup. The siderophore(pyoverdins)-producting bacterial strain Z6 might play an important role in the process of mica weathering. Production of bacterial siderophore may be related to the presence of different mica minerals.%产铁载体细菌与云母类矿物相互作用的研究有助于了解矿物生物风化和土壤形成的演化规律和机理.采用纯培养法自南京龙山废钾矿区酸模根际土壤分离筛选到一株高产荧光铁载体的细菌Z6,通过16S rDNA序列分析和生理生化反应将其鉴定为假单胞菌属(Pseudomonas sp.);通过室温静置培养试验研究Z6菌株与云母的相互作用结果

  19. IS711-based real-time PCR assay as a tool for detection of Brucella spp. in wild boars and comparison with bacterial isolation and serology

    Directory of Open Access Journals (Sweden)

    Miserez Raymond

    2009-07-01

    Full Text Available Abstract Background Control of brucellosis in livestock, wildlife and humans depends on the reliability of the methods used for detection and identification of bacteria. In the present study, we describe the evaluation of the recently established real-time PCR assay based on the Brucella-specific insertion sequence IS711 with blood samples from 199 wild boars (first group of animals and tissue samples from 53 wild boars (second group of animals collected in Switzerland. Results from IS711 real-time PCR were compared to those obtained by bacterial isolation, Rose Bengal Test (RBT, competitive ELISA (c-ELISA and indirect ELISA (i-ELISA. Results In the first group of animals, IS711 real-time PCR detected infection in 11.1% (16/144 of wild boars that were serologically negative. Serological tests showed different sensitivities [RBT 15.6%, c-ELISA 7.5% and i-ELISA 5.5%] and only 2% of blood samples were positive with all three tests, which makes interpretation of the serological results very difficult. Regarding the second group of animals, the IS711 real-time PCR detected infection in 26% of animals, while Brucella spp. could be isolated from tissues of only 9.4% of the animals. Conclusion The results presented here indicate that IS711 real-time PCR assay is a specific and sensitive tool for detection of Brucella spp. infections in wild boars. For this reason, we propose the employment of IS711 real-time PCR as a complementary tool in brucellosis screening programs and for confirmation of diagnosis in doubtful cases.

  20. Construction and characterization of two bacterial artificial chromosome libraries of pea (Pisum sativum L.) for the isolation of economically important genes.

    Science.gov (United States)

    Coyne, C J; McClendon, M T; Walling, J G; Timmerman-Vaughan, G M; Murray, S; Meksem, K; Lightfoot, D A; Shultz, J L; Keller, K E; Martin, R R; Inglis, D A; Rajesh, P N; McPhee, K E; Weeden, N F; Grusak, M A; Li, C-M; Storlie, E W

    2007-09-01

    Pea (Pisum sativum L.) has a genome of about 4 Gb that appears to share conserved synteny with model legumes having genomes of 0.2-0.4 Gb despite extensive intergenic expansion. Pea plant inventory (PI) accession 269818 has been used to introgress genetic diversity into the cultivated germplasm pool. The aim here was to develop pea bacterial artificial chromosome (BAC) libraries that would enable the isolation of genes involved in plant disease resistance or control of economically important traits. The BAC libraries encompassed about 3.2 haploid genome equivalents consisting of partially HindIII-digested DNA fragments with a mean size of 105 kb that were inserted in 1 of 2 vectors. The low-copy oriT-based T-DNA vector (pCLD04541) library contained 55 680 clones. The single-copy oriS-based vector (pIndigoBAC-5) library contained 65 280 clones. Colony hybridization of a universal chloroplast probe indicated that about 1% of clones in the libraries were of chloroplast origin. The presence of about 0.1% empty vectors was inferred by white/blue colony plate counts. The usefulness of the libraries was tested by 2 replicated methods. First, high-density filters were probed with low copy number sequences. Second, BAC plate-pool DNA was used successfully to PCR amplify 7 of 9 published pea resistance gene analogs (RGAs) and several other low copy number pea sequences. Individual BAC clones encoding specific sequences were identified. Therefore, the HindIII BAC libraries of pea, based on germplasm accession PI 269818, will be useful for the isolation of genes underlying disease resistance and other economically important traits.

  1. Bacteriophage-encoded shiga toxin gene in atypical bacterial host

    Directory of Open Access Journals (Sweden)

    Casas Veronica

    2011-07-01

    Full Text Available Abstract Background Contamination from fecal bacteria in recreational waters is a major health concern since bacteria capable of causing human disease can be found in animal feces. The Dog Beach area of Ocean Beach in San Diego, California is a beach prone to closures due to high levels of fecal indicator bacteria (FIB. A potential source of these FIB could be the canine feces left behind by owners who do not clean up after their pets. We tested this hypothesis by screening the DNA isolated from canine feces for the bacteriophage-encoded stx gene normally found in the virulent strains of the fecal bacterium Escherichia coli. Results Twenty canine fecal samples were collected, processed for total and bacterial fraction DNA, and screened by PCR for the stx gene. The stx gene was detected in the total and bacterial fraction DNA of one fecal sample. Bacterial isolates were then cultivated from the stx-positive fecal sample. Eighty nine of these canine fecal bacterial isolates were screened by PCR for the stx gene. The stx gene was detected in five of these isolates. Sequencing and phylogenetic analyses of 16S rRNA gene PCR products from the canine fecal bacterial isolates indicated that they were Enterococcus and not E. coli. Conclusions The bacteriophage-encoded stx gene was found in multiple species of bacteria cultivated from canine fecal samples gathered at the shoreline of the Dog Beach area of Ocean Beach in San Diego, California. The canine fecal bacteria carrying the stx gene were not the typical E. coli host and were instead identified through phylogenetic analyses as Enterococcus. This suggests a large degree of horizontal gene transfer of exotoxin genes in recreational waters.

  2. Isolation of prawn ( Exopalaemon carinicauda) lipopolysaccharide and β-1, 3-glucan binding protein gene and its expression in responding to bacterial and viral infections

    Science.gov (United States)

    Ge, Qianqian; Li, Jian; Duan, Yafei; Li, Jitao; Sun, Ming; Zhao, Fazhen

    2016-04-01

    The pattern recognition proteins (PRPs) play a major role in immune response of crustacean to resist pathogens. In the present study, as one of PRPs, lipopolysaccharide and β-1, 3-glucan binding protein (LGBP) gene in the ridge tail white prawn ( Exopalaemon carinicauda) ( EcLGBP) was isolated. The full-length cDNA of EcLGBP was 1338 bp, encoding a polypeptide of 366 amino acid residules. The deduced amino acid sequence of EcLGBP shared high similarities with LGBP and BGBP from other crustaceans. Some conservative domains were predicted in EcLGBP sequence. EcLGBP constitutively expressed in most tissues at different levels, and the highest expression was observed in hepatopancreas. With infection time, the cumulative mortality increased gradually followed by the proliferation of Vibrio parahaemolyticus and white spot syndrome virus (WSSV). The expression of EcLGBP in response to V. parahaemolyticus infection was up-regulated in hemocytes and hepatopancreas, and the up-regulation in hepatopancreas was earlier than that in hemocytes. EcLGBP expression after WSSV infection increased at 3 h, then significantly decreased in both hemocytes and hepatopancreas. The results indicated that EcLGBP was involved in the immune defense against bacterial and viral infections.