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Journal of Materials Science. Materials... Nov 2018This study validated the utilization of triacylglycerides (TAGs) by Pseudomonas mendocina CH50, a wild type strain, resulting in the production of novel mcl-PHAs with...
This study validated the utilization of triacylglycerides (TAGs) by Pseudomonas mendocina CH50, a wild type strain, resulting in the production of novel mcl-PHAs with unique physical properties. A PHA yield of 58% dcw was obtained using 20 g/L of coconut oil. Chemical and structural characterisation confirmed that the mcl-PHA produced was a terpolymer comprising of three different repeating monomer units, 3-hydroxyoctanoate, 3-hydroxydecanoate and 3-hydroxydodecanoate or P(3HO-3HD-3HDD). Bearing in mind the potential of P(3HO-3HD-3HDD) in biomedical research, especially in neural tissue engineering, in vitro biocompatibility studies were carried out using NG108-15 (neuronal) cells. Cell viability data confirmed that P(3HO-3HD-3HDD) supported the attachment and proliferation of NG108-15 and was therefore confirmed to be biocompatible in nature and suitable for neural regeneration.
Topics: Animals; Cell Culture Techniques; Cell Line, Tumor; Cell Proliferation; Cell Survival; Coconut Oil; Materials Testing; Mice; Polyhydroxyalkanoates; Pseudomonas mendocina; Rats
PubMed: 30506294
DOI: 10.1007/s10856-018-6183-9 -
Journal of Bacteriology Sep 1991Pseudomonas mendocina KR1 metabolizes toluene as a carbon source by a previously unknown pathway. The initial step of the pathway is hydroxylation of toluene to form...
Pseudomonas mendocina KR1 metabolizes toluene as a carbon source by a previously unknown pathway. The initial step of the pathway is hydroxylation of toluene to form p-cresol by a multicomponent toluene-4-monooxygenase (T4MO) system. The T4MO enzyme system has broad substrate specificity and provides a new opportunity for biodegradation of toxic compounds and bioconversions. Its known activities include conversion of a variety of phenyl compounds into the phenolic derivatives and the complete degradation of trichloroethylene. We have cloned and characterized a gene cluster from KR1 that determines the offO activity. To clone the T4MO genes, KR1 DNA libraries were constructed in Escherichia coli HB101 by using a broad-host-range vector and transferred to a KR1 mutant able to grow on p-cresol but not on toluene. An insert consisting of two SacI fragments of identical size (10.2 kb) was shown to complement the mutant for growth on toluene. One of the SacI fragments, when cloned into the E. coli vector pUC19, was found to direct the synthesis of indigo dye. The indigo-forming property was correlated with the presence of T4MO activity. The T4MO genes were mapped to a 3.6-kb region, and the direction of transcription was determined. DNA sequencing and N-terminal amino acid determination identified a five-gene cluster, tmoABCDE, within this region. Expression of this cluster carrying a single mutation in each gene demonstrated that each of the five genes is essential for T4MO activity. Other evidence presented indicated that none of the tmo genes was involved in the regulation of the tmo gene cluster, in the control of substrate transport for the T4MO system, or in major processing of the products of the tmo genes. It was tentatively concluded that the tmoABCDE genes encode structural polypeptides of the T4MO enzyme system. One of the tmo genes was tentatively identified as a ferredoxin gene.
Topics: Amino Acid Sequence; Base Sequence; Biodegradation, Environmental; Chromatography, High Pressure Liquid; Cloning, Molecular; DNA, Bacterial; Escherichia coli; Ferredoxins; Genes, Bacterial; Molecular Sequence Data; Multigene Family; Mutagenesis; Oxygenases; Peptide Mapping; Plasmids; Pseudomonas; Restriction Mapping; Sequence Homology, Nucleic Acid; Toluene; Transcription, Genetic; Trypsin
PubMed: 1885512
DOI: 10.1128/jb.173.17.5315-5327.1991 -
Bioscience, Biotechnology, and... Jul 2016Conditions for the optimal production of polyhydroxyalkanoate (PHA) by Pseudomonas mendocina PSU using a biodiesel liquid waste (BLW) were determined by response surface...
Conditions for the optimal production of polyhydroxyalkanoate (PHA) by Pseudomonas mendocina PSU using a biodiesel liquid waste (BLW) were determined by response surface methodology. These were an initial carbon to nitrogen ratio (C/N) of 40 (mole/mole), an initial pH of 7.0, and a temperature of 35 °C. A biomass and PHA concentration of 3.65 g/L and about 2.6 g/L (77% DCW), respectively, were achieved in a growth associated process using 20 g/L glycerol in the BLW after 36 h of exponential growth. The PHA monomer compositions were 3HB (3-hydroxybutyrate), a short-chain-length-PHA, and the medium-chain-length-PHA e.g. 3-hydroxyoctanoate and 3-hydroxydecanoate. Both the phbC and phaC genes were characterized. The phbC enzyme had not been previously detected in a Pseudomonas mendocina species. A 2.15 g/L of an exopolysaccharide, alginate, was also produced with a similar composition to that of other Pseudomonas species.
Topics: 3-Hydroxybutyric Acid; Alginates; Biodegradation, Environmental; Biofuels; Caprylates; Carbon; Decanoic Acids; Factor Analysis, Statistical; Gene Expression; Genes, Bacterial; Glucuronic Acid; Glycerol; Hexuronic Acids; Hydrogen-Ion Concentration; Industrial Waste; Nitrogen; Phylogeny; Polyhydroxyalkanoates; Pseudomonas mendocina; Temperature
PubMed: 26981955
DOI: 10.1080/09168451.2016.1158628 -
Journal of Industrial Microbiology &... Aug 2010A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of three Pseudomonas species belonging to the... (Comparative Study)
Comparative Study
A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of three Pseudomonas species belonging to the mendocina sublineage (P. oleovorans, P. pseudoalcaligenes, and P. oleovorans subsp. lubricantis) found in contaminated metalworking fluids (MWFs). These microbes are the primary colonizers and serve as indicator organisms of biodegradation of used MWFs. Molecular techniques such as qPCR are preferred for the detection of these microbes since they grow poorly on typical growth media such as R2A agar and Pseudomonas isolation agar (PIA). Traditional culturing techniques not only underestimate the actual distribution of these bacteria but are also time-consuming. The primer-probe pair developed from gyrase B (gyrB) sequences of the targeted bacteria was highly sensitive and specific for the three species. qPCR was performed with both whole cell and genomic DNA to confirm the specificity and sensitivity of the assay. The sensitivity of the assay was 10(1) colony forming units (CFU)/ml for whole cell and 13.7 fg with genomic DNA. The primer-probe pair was successful in determining concentrations from used MWF samples, indicating levels between 2.9 x 10(3) and 3.9 x 10(6) CFU/ml. In contrast, the total count of Pseudomonas sp. recovered on PIA was in the range of <1.0 x 10(1) to 1.4 x 10(5) CFU/ml for the same samples. Based on these results from the qPCR assay, the designed TaqMan primer-probe pair can be efficiently used for rapid (within 2 h) determination of the distribution of these species of Pseudomonas in contaminated MWFs.
Topics: Bacterial Proteins; Bacteriological Techniques; DNA Gyrase; DNA Primers; Industrial Waste; Oligonucleotide Probes; Polymerase Chain Reaction; Pseudomonas; Sensitivity and Specificity; Water Microbiology
PubMed: 20458609
DOI: 10.1007/s10295-010-0731-8 -
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 -
Journal of Hazardous Materials Sep 2005A pentachlorophenol (PCP) degrading bacterium was isolated from PCP-contaminated soils and identified as Pseudomonas mendocina NSYSU (P. mendocina NSYSU). The main...
A pentachlorophenol (PCP) degrading bacterium was isolated from PCP-contaminated soils and identified as Pseudomonas mendocina NSYSU (P. mendocina NSYSU). The main objectives of this study were to (1) clarify the factors affecting the ability and efficiency of PCP biodegradation by P. mendocina NSYSU, and (2) optimize the use of this bacterium in bioremediation of PCP. Microcosm experiments were conducted to fulfill the objectives. In batch cultures, P. mendocina NSYSU used PCP as its sole source of carbon and energy and was capable of completely degrading this compound. This was confirmed by the stoichiometric release of chloride ion. Moreover, P. mendocina NSYSU was able to mineralize a high concentration of PCP (150 mg/L). Results from the oxygen concentration experiment reveal that the growth of P. mendocina NSYSU was inhibited under low oxygen and anaerobic conditions. Results indicate that the optimal growth conditions for P. mendocina NSYSU include the following: slightly acidic (6
mendocina NSYSU is able to effectively biodegrade PCP and its biodegradation byproducts without the accumulation of inhibitory toxic compounds. Results from this study could be used to assist the optimization of its use in bioremediation of PCP. Topics: Biodegradation, Environmental; Carbon; Chlorides; Environment; Oxygen; Phencyclidine; Pseudomonas mendocina
PubMed: 15979238
DOI: 10.1016/j.jhazmat.2005.03.051 -
Applied and Environmental Microbiology Oct 2006N-Nitrosodimethylamine (NDMA) is a potent carcinogen and an emerging contaminant in groundwater and drinking water. The metabolism of NDMA in mammalian cells has been...
N-Nitrosodimethylamine (NDMA) is a potent carcinogen and an emerging contaminant in groundwater and drinking water. The metabolism of NDMA in mammalian cells has been widely studied, but little information is available concerning the microbial transformation of this compound. The objective of this study was to elucidate the pathway(s) of NDMA biotransformation by Pseudomonas mendocina KR1, a strain that possesses toluene-4-monooxygenase (T4MO). P. mendocina KR1 was observed to initially oxidize NDMA to N-nitrodimethylamine (NTDMA), a novel metabolite. The use of 18O2 and H(2)18O revealed that the oxygen added to NDMA to produce NTDMA was derived from atmospheric O2. Experiments performed with a pseudomonad expressing cloned T4MO confirmed that T4MO catalyzes this initial reaction. The NTDMA produced by P. mendocina KR1 did not accumulate, but rather it was metabolized further to produce N-nitromethylamine (88 to 94% recovery) and a trace amount of formaldehyde (HCHO). Small quantities of methanol (CH3OH) were also detected when the strain was incubated with NDMA but not during incubation with either NTDMA or HCHO. The formation of methanol is hypothesized to occur via a second, minor pathway mediated by an initial alpha-hydroxylation of the nitrosamine. Strain KR1 did not grow on NDMA or mineralize significant quantities of the compound to carbon dioxide, suggesting that the degradation process is cometabolic.
Topics: Biotransformation; Dimethylnitrosamine; Nitroso Compounds; Pseudomonas mendocina; Water Pollutants, Chemical
PubMed: 16950909
DOI: 10.1128/AEM.01535-06 -
Molecular Biology Reports May 2024
PubMed: 38704763
DOI: 10.1007/s11033-024-09536-z -
International Journal of Systematic and... Jan 2009Strain 78-123T was isolated from a sample of a bird's nest situated on the bank of Qiongtailan River in the region of Tuomuer Peak of Tianshan Mountain in the Xin-jiang...
Strain 78-123T was isolated from a sample of a bird's nest situated on the bank of Qiongtailan River in the region of Tuomuer Peak of Tianshan Mountain in the Xin-jiang Uygur Autonomous Region in north-western China. Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain 78-123T was related to members of the genus Pseudomonas. 16S rRNA gene sequence similarity between strain 78-123T and Pseudomonas mendocina ATCC 25411T, Pseudomonas pseudoalcaligenes JCM 5968T and Pseudomonas alcaliphila AL15-21T was 97.1, 97.4 and 97.5 %, respectively. The major cellular fatty acids were C(16 : 0), C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH, C(18 : 1)omega7c and C(12 : 0). The G+C content was 60.4 mol%. On the basis of the phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, the novel species Pseudomonas tuomuerensis sp. nov. is proposed, with the type strain 78-123T (=CGMCC 1.1365T =JCM 14085T).
Topics: Animals; Bacterial Typing Techniques; Base Composition; Birds; China; DNA, Bacterial; DNA, Ribosomal; Fatty Acids; Genes, rRNA; Housing, Animal; Nucleic Acid Hybridization; Phenotype; Phylogeny; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Species Specificity
PubMed: 19126738
DOI: 10.1099/ijs.0.000547-0 -
Microbial Ecology Nov 2009Arbuscular mycorrhizal (AM) symbiosis and plant-growth-promoting rhizobacterium (PGPR) can alleviate the effects of water stress in plants, but it is unknown whether...
Differential effects of Pseudomonas mendocina and Glomus intraradices on lettuce plants physiological response and aquaporin PIP2 gene expression under elevated atmospheric CO2 and drought.
Arbuscular mycorrhizal (AM) symbiosis and plant-growth-promoting rhizobacterium (PGPR) can alleviate the effects of water stress in plants, but it is unknown whether these benefits can be maintained at elevated CO2. Therefore, we carried out a study where seedlings of Lactuca sativa were inoculated with the AM fungus (AMF) Glomus intraradices N.C. Schenk & G.S. Sm. or the PGPR Pseudomonas mendocina Palleroni and subjected to two levels of watering and two levels of atmospheric CO2 to ascertain their effects on plant physiological parameters and gene expression of one PIP aquaporin in roots. The inoculation with PGPR produced the greatest growth in lettuce plants under all assayed treatments as well as the highest foliar potassium concentration and leaf relative water content under elevated [CO2] and drought. However, under such conditions, the PIP2 gene expression remained almost unchanged. G. intraradices increased significantly the AMF colonization, foliar phosphorus concentration and leaf relative water content in plants grown under drought and elevated [CO2]. Under drought and elevated [CO2], the plants inoculated with G. intraradices showed enhanced expression of the PIP2 gene as compared to P. mendocina or control plants. Our results suggest that both microbial inoculation treatments could help to alleviate drought at elevated [CO2]. However, the PIP2 gene expression was increased only by the AMF but not by the PGPR under these conditions.
Topics: Aquaporins; Biomass; Carbon Dioxide; Droughts; Gene Expression Regulation, Plant; Genes, Plant; Lactuca; Mycorrhizae; Phosphorus; Plant Leaves; Plant Proteins; Plant Roots; Plant Transpiration; Pseudomonas mendocina; Symbiosis; Water
PubMed: 19495853
DOI: 10.1007/s00248-009-9544-6