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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