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Protoplasma Jul 2016Thermoplastic-based materials are recalcitrant in nature, which extensive use affect environmental health. Here, we attempt to compare the response of indigenously...
Thermoplastic-based materials are recalcitrant in nature, which extensive use affect environmental health. Here, we attempt to compare the response of indigenously produced bacterial consortium-I and consortium-II in degrading polyvinyl chloride (PVC). These consortia were developed by using different combination of bacterial strains of Pseudomonas otitidis, Bacillus cereus, and Acanthopleurobacter pedis from waste disposal sites of Northern India after their identification via 16S rDNA sequencing. The progressive degradation of PVC by consortia was examined via scanning electron microscopy, atomic force microscopy, UV-vis, FT-IR spectra, gel permeation chromatography, and differential scanning calorimetry analysis at different incubations and time intervals. The consortium-II was superior over consortium-I in degrading the PVC. Further, the carbon source utilization analysis revealed that the extensive use of consortia has not any effect on functional diversity of native soil microbes.
Topics: Biodegradation, Environmental; Microbial Consortia; Molecular Typing; Polyvinyl Chloride; RNA, Ribosomal, 16S; Soil Microbiology; Soil Pollutants
PubMed: 26231814
DOI: 10.1007/s00709-015-0855-9 -
Journal of Global Antimicrobial... Jun 2015Pseudomonas spp. are ubiquitous in nature. Carbapenem resistance in environmental isolates of members of this genus is thought to be rare but the exact resistance rate...
Pseudomonas spp. are ubiquitous in nature. Carbapenem resistance in environmental isolates of members of this genus is thought to be rare but the exact resistance rate is unknown. In this study, carbapenem-resistant Pseudomonas spp. were isolated from chicken and pork samples and the mechanisms underlying the carbapenem resistance in these strains were investigated. A total of 16 carbapenem-resistant Pseudomonas aeruginosa, Pseudomonas putida and Pseudomonas otitidis isolates were recovered from eight samples of chicken and pork. The isolates exhibited meropenem minimum inhibitory concentrations (MICs) of 8 to ≥32mg/L and imipenem MICs of <0.5-16mg/L yet did not harbour any acquired carbapenemase genes. Meropenem resistance in various strains was found to be mediated by efflux systems only, whereas overexpression of MexAB-OprM efflux pump and lack of OprD porin were responsible for carbapenem resistance in P. aeruginosa. The intrinsic metallo-β-lactamase gene bla in P. otitidis and overexpression of the TtgABC efflux system in P. putida were also responsible for carbapenem resistance in these organisms. In conclusion, this study reports for the first time the isolation of carbapenem-resistant P. aeruginosa, P. otitidis and P. putida strains from food. The resistance mechanisms of these strains are rarely due to production of carbapenemases. Further selection of such carbapenem-resistant Pseudomonas spp. in the environment and the risk by which they are transmitted to clinical settings are of great public health concern.
PubMed: 27873658
DOI: 10.1016/j.jgar.2015.03.006 -
Antimicrobial Agents and Chemotherapy Mar 2015The POM-1 metallo-β-lactamase is a subclass B3 resident enzyme produced by Pseudomonas otitidis, a pathogen causing otic infections. The enzyme was overproduced in...
The POM-1 metallo-β-lactamase is a subclass B3 resident enzyme produced by Pseudomonas otitidis, a pathogen causing otic infections. The enzyme was overproduced in Escherichia coli BL21(DE3), purified by chromatography, and subjected to structural and functional analysis. The purified POM-1 is a tetrameric enzyme of broad substrate specificity with higher catalytic activities with penicillins and carbapenems than with cephalosporins.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Carbapenems; Catalysis; Cephalosporins; Escherichia coli; Penicillins; Pseudomonas; beta-Lactamases
PubMed: 25512428
DOI: 10.1128/AAC.03843-14 -
The Plant Pathology Journal Jun 2013We previously developed a sequential screening procedure to select antagonistic bacterial strains against Phytophthora capsici in pepper plants. In this study, we used a...
We previously developed a sequential screening procedure to select antagonistic bacterial strains against Phytophthora capsici in pepper plants. In this study, we used a modified screening procedure to select effective biocontrol strains against P. capsici; we evaluated the effect of selected strains on Phytophthora blight and anthracnose occurrence and fruit yield in pepper plants under field and plastic house conditions from 2007 to 2009. We selected four potential biocontrol strains (Pseudomonas otitidis YJR27, P. putida YJR92, Tsukamurella tyrosinosolvens YJR102, and Novosphingobium capsulatum YJR107) among 239 bacterial strains. In the 3-year field tests, all the selected strains significantly (P < 0.05) reduced Phytophthora blight without influencing rhizosphere microbial populations; they showed similar or better levels of disease suppressions than in metalaxyl treatment in the 2007 and 2009 tests, but not in the 2008 test. In the 2-year plastic house tests, all the selected strains significantly (P < 0.05) reduced anthracnose incidence in at least one of the test years, but their biocontrol activities were variable. In addition, strains YJR27, YJR92, and YJR102, in certain harvests, increased pepper fruit numbers in field tests and red fruit weights in plastic house tests. Taken together, these results indicate that the screening procedure is rapid and reliable for the selection of potential biocontrol strains against P. capsici in pepper plants. In addition, these selected strains exhibited biocontrol activities against anthracnose, and some of the strains showed plant growth-promotion activities on pepper fruit.
PubMed: 25288942
DOI: 10.5423/PPJ.OA.07.2012.0104 -
ISRN Biotechnology 2013The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic...
The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic pollutants. Such limitation of bioavailability can be overcome by steady-state biofilm-based reactor. The aim of this study was to examine the effect of such multicellular aggregation by naturally existing oil-degrading bacteria on crude oil degradation. Microorganisms, capable of utilizing crude oil as sole carbon source, were isolated from river, estuary and sea-water samples. Biochemical and 16S rDNA analysis of the best degraders of the three sources was found to belong to the Pseudomonas species. Interestingly, one of the isolates was found to be close to Pseudomonas otitidis family which is not reported yet as a degrader of crude oil. Biodegradation of crude oil was estimated by gas chromatography, and biofilm formation near oil-water interface was quantified by confocal laser scanning microscopy. Biofilm supported batches of the isolated Pseudomonas species were able to degrade crude oil much readily and extensively than the planktonic counterparts. Volumetric and topographic analysis revealed that biofilms formed in presence of crude oil accumulate higher biomass with greater thickness compared to the biofilms produced in presence of glucose as sole carbon source.
PubMed: 25937972
DOI: 10.5402/2013/250749 -
Bioresource Technology Nov 2012Polyhydroxyalkanoates (PHA) production using Pseudomonas otitidis, a newly isolated strain from PHA producing bioreactor was investigated using synthetic acids (SA) and...
Polyhydroxyalkanoates (PHA) production using Pseudomonas otitidis, a newly isolated strain from PHA producing bioreactor was investigated using synthetic acids (SA) and acidogenic effluents (AE) from biohydrogen reactor at different organic loading rates (OLRs). P. otitidis showed ability to grow and accumulate PHA, with simultaneous waste remediation. AE showed less PHA production (54%, OLR3), than SA (58%, OLR2). PHA composition showed co-polymer, poly-3(hydroxy butyrate-co-hydroxy valerate), P3(HB-co-HV). Bioprocess evaluation and enzymatic activities showed good correlation with PHA production. Kinetic studies on the growth of bacteria using different models at varying OLR were substantiated with PHA production. High substrate removal was registered at OLR1 (SA, 87%; AE, 82%). AE could be used as an alternative for pure substrates keeping in view of their high cost.
Topics: Acids; Base Sequence; Biocatalysis; Biological Oxygen Demand Analysis; Fatty Acids, Volatile; Hydrogen-Ion Concentration; Kinetics; Models, Biological; Molecular Sequence Data; Phylogeny; Polyhydroxyalkanoates; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, RNA; Substrate Specificity; Waste Disposal, Fluid; Wastewater; Water Purification
PubMed: 22940357
DOI: 10.1016/j.biortech.2012.07.077 -
Bioprocess and Biosystems Engineering Mar 2013The marine strain Pseudomonas otitidis was isolated to hydrolyze the cooked sunflower oil (CSO) followed by the production of lipase. The optimum culture conditions for...
The marine strain Pseudomonas otitidis was isolated to hydrolyze the cooked sunflower oil (CSO) followed by the production of lipase. The optimum culture conditions for the maximum lipase production were determined using Plackett-Burman design and response surface methodology. The maximum lipase production, 1,980 U/ml was achieved at the optimum culture conditions. After purification, an 8.4-fold purity of lipase with specific activity of 5,647 U/mg protein and molecular mass of 39 kDa was obtained. The purified lipase was stable at pH 5.0-9.0 and temperature 30-80 °C. Ca(2+) and Triton X-100 showed stimulatory effect on the lipase activity. The purified lipase was highly stable in the non-polar solvents. The functional groups of the lipase were determined by Fourier transform-infrared (FT-IR) spectroscopy. The purified lipase showed higher hydrolytic activity towards CSO over the other cooked oil wastes. About 92.3 % of the CSO hydrolysis was observed by the lipase at the optimum time 3 h, pH 7.5 and temperature 35 °C. The hydrolysis of CSO obeyed pseudo first order rate kinetic model. The thermodynamic properties of the lipase hydrolysis were studied using the classical Van't Hoff equation. The hydrolysis of CSO was confirmed by FT-IR studies.
Topics: Biotechnology; Detergents; Hydrogen-Ion Concentration; Hydrolysis; Lipase; Lipolysis; Molecular Weight; Octoxynol; Phylogeny; Plant Oils; Solvents; Spectroscopy, Fourier Transform Infrared; Sunflower Oil; Surface Properties; Temperature; Thermodynamics
PubMed: 22833226
DOI: 10.1007/s00449-012-0785-2 -
Diagnostic Microbiology and Infectious... Mar 2012
Topics: Anti-Bacterial Agents; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Typing; Otitis Media; Pseudomonas; Pseudomonas Infections; beta-Lactamases
PubMed: 22209511
DOI: 10.1016/j.diagmicrobio.2011.11.007 -
Antimicrobial Agents and Chemotherapy Jan 2011Susceptibility to several β-lactams and β-lactamase production was investigated in a collection of 20 strains of Pseudomonas otitidis, a new Pseudomonas species that...
Susceptibility to several β-lactams and β-lactamase production was investigated in a collection of 20 strains of Pseudomonas otitidis, a new Pseudomonas species that has been recently recognized in association with otic infections in humans. All strains appeared to be susceptible to piperacillin, cefotaxime, ceftazidime, and aztreonam, while resistance or decreased susceptibility to carbapenems was occasionally observed. All strains were found to express metallo-β-lactamase (MBL) activity and to carry a new subclass B3 MBL gene, named bla(POM), that appeared to be highly conserved in this species. P. otitidis, therefore, is the first example of a pathogenic Pseudomonas species endowed with a resident MBL. The POM-1 protein from P. otitidis type strain MCC10330 exhibits the closest similarity (60 to 64%) to the L1 MBL of Stenotrophomonas maltophilia. Expression in Escherichia coli and Pseudomonas aeruginosa revealed that, similar to L1 and other subclass B3 MBLs, POM-1 confers decreased susceptibility or resistance to carbapenems, penicillins, and cephalosporins but not to aztreonam. Expression of the POM MBL in P. otitidis is apparently constitutive and, in most strains, does not confer a carbapenem-resistant phenotype. However, a strong inoculum size effect was observed for carbapenem MICs, and carbapenem-resistant mutants could be readily selected upon exposure to imipenem, suggesting that carbapenem-based regimens should be considered with caution for P. otitidis infections.
Topics: Amino Acid Sequence; Anti-Bacterial Agents; Bacterial Proteins; Carbapenems; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Molecular Sequence Data; Phylogeny; Pseudomonas; Sequence Homology, Amino Acid; beta-Lactamases
PubMed: 21060106
DOI: 10.1128/AAC.01062-10 -
Journal of Environmental Sciences... 2009Pseudomonas otitidis WL-13, which has a high capacity to decolorize triphenylmethane dyes, was isolated from activated sludge obtained from a wastewater treatment plant...
Pseudomonas otitidis WL-13, which has a high capacity to decolorize triphenylmethane dyes, was isolated from activated sludge obtained from a wastewater treatment plant of a dyeing industry. This strain exhibited a remarkable color-removal capability when tested against several triphenylmethane dyes under both shaking and static conditions at high concentrations of dyes. More than 95% of Malachite Green and Brilliant Green was removed within 12 h at 500 micromol/L dye concentration under shaking conditions. Crystal Violet lost about 13% of its color under the same conditions tested. The rate of decolorization increased when the M9 medium was supplemented with yeast extract. The optimum pH and temperature for color removal were 7-9 and 35-40 degrees C, respectively. The observed changes in the visible spectra and the inspection of bacterial growth indicated the color-removal by the adsorption of dye to the cells during incubation with strains.
Topics: Biodegradation, Environmental; Coloring Agents; Pseudomonas; Trityl Compounds
PubMed: 19862963
DOI: 10.1016/s1001-0742(08)62368-2