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Microbial Biotechnology Nov 2017This study demonstrated the utilization of unprocessed biodiesel waste as a carbon feedstock for Pseudomonas mendocinaCH50, for the production of PHAs. A PHA yield of...
This study demonstrated the utilization of unprocessed biodiesel waste as a carbon feedstock for Pseudomonas mendocinaCH50, for the production of PHAs. A PHA yield of 39.5% CDM was obtained using 5% (v/v) biodiesel waste substrate. Chemical analysis confirmed that the polymer produced was poly(3-hydroxyhexanoate-co-3-hydroxyoctanoate-co-3-hydroxydecanoate-co-3-hydroxydodecanoate) or P(3HHx-3HO-3HD-3HDD). P(3HHx-3HO-3HD-3HDD) was further characterized and evaluated for its use as a tissue engineering scaffold (TES). This study demonstrated that P(3HHx-3HO-3HD-3HDD) was biocompatible with the C2C12 (myoblast) cell line. In fact, the % cell proliferation of C2C12 on the P(3HHx-3HO-3HD-3HDD) scaffold was 72% higher than the standard tissue culture plastic confirming that this novel PHA was indeed a promising new material for soft tissue engineering.
Topics: Animals; Cell Line; Cell Proliferation; Mice; Molecular Structure; Myoblasts; Polyhydroxyalkanoates; Pseudomonas mendocina; Tissue Engineering; Tissue Scaffolds; Waste Products
PubMed: 28905518
DOI: 10.1111/1751-7915.12782 -
Biotechnology Letters Dec 2017An extracellular protease inhibitor (BTPI-301) of trypsin was purified and characterized from an isolate of Pseudomonas mendocina.
OBJECTIVES
An extracellular protease inhibitor (BTPI-301) of trypsin was purified and characterized from an isolate of Pseudomonas mendocina.
RESULTS
BTPI-301was purified to homogeneity by (NH)SO, precipitation, DEAE Sepharose and CNBr-activated Sepharose chromatography. Homogeneity was proved by native PAGE and SDS-PAGE. The intact molecular mass was 11567 Da by MALDI-TOF analysis. BTPI-301was a competitive inhibitor with a Ki of 3.5 × 10 M. It was stable and active at pH 4-12 and also at 4-90 °C for 1 h. Peptide mass fingerprinting by MALDI revealed that the BTPI-301 is a new inhibitor not reported so far with protease inhibitory activity. The pI of the inhibitor was 3.8. The stoichiometry of trypsin-BTPI-301 interaction is 1:1. The inhibitor was specific towards trypsin.
CONCLUSION
A pH tolerant and thermostable protease inhibitor BTPI-301 active against trypsin was purified and characterized from P. mendocina that could be developed and used as biopreservative as well as biocontrol agent.
Topics: Bacterial Proteins; Hot Temperature; Hydrogen-Ion Concentration; Kinetics; Protease Inhibitors; Protein Stability; Pseudomonas mendocina; Trypsin; Trypsin Inhibitors
PubMed: 28861750
DOI: 10.1007/s10529-017-2424-0 -
Scientific Reports Aug 2017Aerobic denitrification is a process reducing the nitrate into gaseous nitrogen forms in the presence of oxygen gas, which makes the nitrification and denitrification...
Aerobic denitrification is a process reducing the nitrate into gaseous nitrogen forms in the presence of oxygen gas, which makes the nitrification and denitrification performed simultaneously. However, little was known on the diversity of the culturable aerobic denitrifying bacteria in the surface water system. In this study, 116 strains of aerobic denitrifying bacteria were isolated from the sediment, water and biofilm samples in Liangshui River of Beijing. These bacteria were classified into 14 genera based on the 16 S rDNA, such as Pseudomonas, Rheinheimera, and Gemmobacter. The Pseudomonas sp., represented by the Pseudomonas stutzeri, Pseudomonas mendocina and Pseudomonas putida, composed the major culturable aerobic denitrifiers of the river, followed by Ochrobactrum sp. and Rheinheimera sp. The PCA plot showed the unclassified Pseudomonas sp. and Rheinheimera pacifica preferred to inhabit in biofilm phase while one unclassified Ochrobactrum sp. and Pseudomonas resinovorans had higher abundance in the sediment. In the overlying water, the Pseudomonas stutzeri and Ochrobactrum rhizosphaerae were found to have higher abundance, indicating these aerobic denitrifiers had different habitat-preferable characteristics among the 3 phases of river system. The findings may help select the niche to isolate the aerobic denitrifiers and facilitate the bioaugmentation-based purification of the nitrate polluted surface water.
Topics: Bacteria, Aerobic; Biofilms; Denitrification; Geologic Sediments; Microbiota; Nitrogen-Fixing Bacteria; Rivers
PubMed: 28855587
DOI: 10.1038/s41598-017-09556-9 -
3 Biotech Oct 2017Poly(3-hydroxybutyrate--4-hydroxybutyrate) (P(3HB--4HB)) is a biodegradable plastic that is extensively utilized in many fields. In this work, P(3HB--4HB) powder was...
Poly(3-hydroxybutyrate--4-hydroxybutyrate) (P(3HB--4HB)) is a biodegradable plastic that is extensively utilized in many fields. In this work, P(3HB--4HB) powder was degraded by for the preparation of low-molecular-mass (LMW) P(3HB--4HB). After degradation, the remaining P(3HB--4HB) powder was analyzed via gel permeation chromatography (GPC), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and proton nuclear magnetic resonance (H NMR) spectroscopy. The degradation of P(3HB--4HB) by occurred in two stages: the fast degradation stage (0-8 h) and the slow degradation stage (8-24 h). GPC analysis showed that the molecular weight of P(3HB--4HB) gradually decreased with degradation time. After 24 h of degradation, the weight-average molecular weight of P(3HB--4HB) was reduced to 4-5 kDa. DSC and XRD analyses both verified that the degree of crystallinity decreased with prolonged degradation time. The melting temperature of the degraded powder, however, remained unchanged. FTIR and H NMR analyses of the degraded powder showed that no new material was produced during degradation. Thus, the degradation of P(3HB--4HB) by could be used to produce LMW P(3HB--4HB) for use in various applications, such as the synthesis of amphiphilic block copolymers.
PubMed: 28828288
DOI: 10.1007/s13205-017-0824-4 -
3 Biotech Jul 2017Endosulfan contamination is one of the major concerns of soil ecosystem, which causes detrimental effects not only to humans but also to animals and plants. Therefore,...
Endosulfan contamination is one of the major concerns of soil ecosystem, which causes detrimental effects not only to humans but also to animals and plants. Therefore, the aim of this study was to isolate and identify a novel bacterial strain capable of degrading endosulfan in agriculture contaminated soils. A novel bacterial strain was isolated from the sugarcane field contaminated with endosulfan, and was named as ZAM1 strain. The ZAM1 bacterial strain was further identified as Pseudomonas mendocina based on the biochemical and molecular analysis. 16sRNA sequence analysis of ZAM1 strain shows maximum similarity with known endosulfan-degrading bacteria (Pseudomonas putida), respectively. Enrichment was carried out using the endosulfan as sole sulfur source. The ZAM1 strain was able to use α and β endosulfan as a sole sulfur source. Our results showed that ZAM1 strain degrades endosulfan >64.5% (50 mg/l) after 12 days of incubation. The residues were analyzed by GC-MS analysis and confirmed the formation of metabolites of dieldrin, 2 heptanone, methyl propionate, and endosulfan lactone compounds. Hence, these results indicate that the ZAM1 strain is a promising bacterial source for detoxification of endosulfan residues in the environment.
PubMed: 28667651
DOI: 10.1007/s13205-017-0823-5 -
Nefrologia : Publicacion Oficial de La... 2017
Topics: Humans; Male; Peritoneal Dialysis; Peritonitis; Pseudomonas Infections; Pseudomonas mendocina; Young Adult
PubMed: 28655401
DOI: 10.1016/j.nefro.2016.11.004 -
AMB Express Dec 2017Root exudates are chemical compounds that are released from living plant roots and provide significant energy, carbon, nitrogen and phosphorus sources for microbes...
Root exudates are chemical compounds that are released from living plant roots and provide significant energy, carbon, nitrogen and phosphorus sources for microbes inhabiting the rhizosphere. The exudates shape the microflora associated with the plant, as well as influences the plant health and productivity. Therefore, a better understanding of the trophic link that is established between the plant and the associated bacteria is necessary. In this study, a comprehensive survey on the utilization of grapevine and rootstock related organic acids were conducted on a vineyard soil isolate which is Pseudomonas mendocina strain S5.2. Phenotype microarray analysis has demonstrated that this strain can utilize several organic acids including lactic acid, succinic acid, malic acid, citric acid and fumaric acid as sole growth substrates. Complete genome analysis using single molecule real-time technology revealed that the genome consists of a 5,120,146 bp circular chromosome and a 252,328 bp megaplasmid. A series of genetic determinants associated with the carbon utilization signature of the strain were subsequently identified in the chromosome. Of note, the coexistence of genes encoding several iron-sulfur cluster independent isoenzymes in the genome indicated the importance of these enzymes in the events of iron deficiency. Synteny and comparative analysis have also unraveled the unique features of D-lactate dehydrogenase of strain S5.2 in the study. Collective information of this work has provided insights on the metabolic role of this strain in vineyard soil rhizosphere.
PubMed: 28655216
DOI: 10.1186/s13568-017-0437-7 -
Emerging Infectious Diseases Feb 2017We isolated IMP-19-producing Pseudomonas aeruginosa from 7 patients with nosocomial infections linked to contaminated sinks in France. We showed that bla was located on...
We isolated IMP-19-producing Pseudomonas aeruginosa from 7 patients with nosocomial infections linked to contaminated sinks in France. We showed that bla was located on various class 1 integrons among 8 species of gram-negative bacilli detected in sinks: P. aeruginosa, Achromobacter xylosoxidans, A. aegrifaciens, P. putida, Stenotrophomonas maltophilia, P. mendocina, Comamonas testosteroni, and Sphingomonas sp.
Topics: Cross Infection; Drug Resistance, Bacterial; France; Humans; Microbial Sensitivity Tests; Pseudomonas Infections; Pseudomonas aeruginosa; Water Microbiology; beta-Lactamase Inhibitors; beta-Lactamases
PubMed: 28098548
DOI: 10.3201/eid2302.160649 -
Applied Microbiology and Biotechnology May 2017Bioremediation usually exhibits low removal efficiency toward hexane because of poor water solubility, which limits the mass transfer rate between the substrate and...
Bioremediation usually exhibits low removal efficiency toward hexane because of poor water solubility, which limits the mass transfer rate between the substrate and microorganism. This work aimed to enhance the hexane degradation rate by increasing cell surface hydrophobicity (CSH) of the degrader, Pseudomonas mendocina NX-1. The CSH of P. mendocina NX-1 was manipulated by treatment with starch and chitosan solution of varied concentrations, reaching a maximum hydrophobicity of 52%. The biodegradation of hexane conformed to the Haldane inhibition model, and the maximum degradation rate (ν ) of the cells with 52% CSH was 0.72 mg (mg cell)·h in comparison with 0.47 mg (mg cell)·h for cells with 15% CSH. The production of CO by high CSH cells was threefold higher than that by cells at 15% CSH within 30 h, and the cumulative rates of O consumption were 0.16 and 0.05 mL/h, respectively. High CSH was related to low negative charge carried by the cell surface and probably reduced the repulsive electrostatic interactions between hexane and microorganisms. The FT-IR spectra of cell envelopes demonstrated that the methyl chain was inversely proportional to increasing CSH values, but proteins exhibited a positive effect to CSH enhancement. The ratio of extracellular proteins and polysaccharides increased from 0.87 to 3.78 when the cells were treated with starch and chitosan, indicating their possible roles in increased CSH.
Topics: Biotransformation; Carbon Dioxide; Chitosan; Hexanes; Hydrophobic and Hydrophilic Interactions; Oxygen; Pseudomonas mendocina; Spectroscopy, Fourier Transform Infrared; Starch; Surface Properties
PubMed: 28091789
DOI: 10.1007/s00253-017-8100-4 -
Nature Nov 2016The universal Per-ARNT-Sim (PAS) domain functions as a signal transduction module involved in sensing diverse stimuli such as small molecules, light, redox state and...
The universal Per-ARNT-Sim (PAS) domain functions as a signal transduction module involved in sensing diverse stimuli such as small molecules, light, redox state and gases. The highly evolvable PAS scaffold can bind a broad range of ligands, including haem, flavins and metal ions. However, although these ligands can support catalytic activity, to our knowledge no enzymatic PAS domain has been found. Here we report characterization of the first PAS enzyme: a haem-dependent oxidative N-demethylase. Unrelated to other amine oxidases, this enzyme contains haem, flavin mononucleotide, 2Fe-2S and tetrahydrofolic acid cofactors, and specifically catalyses the NADPH-dependent oxidation of dimethylamine. The structure of the α subunit reveals that it is a haem-binding PAS domain, similar in structure to PAS gas sensors. The dimethylamine substrate forms part of a highly polarized oxygen-binding site, and directly assists oxygen activation by acting as both an electron and proton donor. Our data reveal that the ubiquitous PAS domain can make the transition from sensor to enzyme, suggesting that the PAS scaffold can support the development of artificial enzymes.
Topics: Binding Sites; Coenzymes; Crystallography, X-Ray; Dimethylamines; Flavin Mononucleotide; Heme; Iron-Sulfur Proteins; Models, Molecular; NADP; Oxidation-Reduction; Oxidoreductases, N-Demethylating; Oxygen; Protein Domains; Protein Subunits; Pseudomonas mendocina; Tetrahydrofolates
PubMed: 27851736
DOI: 10.1038/nature20159