-
Journal of Basic Microbiology Aug 2019We unearthed some interesting microecological discoveries while selecting for the most beneficial bacterial strains to be used as probiotics in Lecane inermis rotifer...
We unearthed some interesting microecological discoveries while selecting for the most beneficial bacterial strains to be used as probiotics in Lecane inermis rotifer mass culture. For 3 years, we maintained the cultures of L. inermis, with selection for the highest growth rate and resistance to potential contamination. Then, we conducted further selection and isolation in two groups: rotifers inoculated with the bacterial consortium isolated from the rotifer cultures, and rotifers fed with a commercial bioproduct. Selection was conducted in demanding conditions, with particulate matter suspended in spring water as a substrate, without aeration and under strong consumer pressure, and led to selection of two cultivable strains isolated from the optimal rotifers culture. According to molecular analysis, these strains were Aeromonas veronii and Pseudomonas mosselii. Biolog® ECO plate tests showed that both investigated bacterial communities metabolized wide but similar range of substrates. Therefore, intensely selective conditions led to considerable reduction in bacterial community regarding taxonomy, but not in metabolic activity, showing a functional composition decoupling. Aside from this result, our novel selection method dedicated to the sustainable culture of two trophic levels, a directed selection procedure (DSC), could potentially lead to the development of biotechnologically valuable strains with high metabolic activity and the ability to metabolize different sorts of substrate without harmful impact on higher trophic levels.
Topics: Animals; Bacteria; Biodiversity; Culture Media; Microbial Consortia; Nutrients; Phylogeny; Rotifera; Sewage
PubMed: 31259432
DOI: 10.1002/jobm.201900167 -
Biodegradation Aug 2019Biosurfactants are one among the best alternative for synthetic surfactants that are exploited by many researchers. Several agro wastes help to reduce the cost...
Biosurfactants are one among the best alternative for synthetic surfactants that are exploited by many researchers. Several agro wastes help to reduce the cost biosurfactants by being renewable and economical. The present research focuses on the biosurfactant production from Pseudomonas mosselii utilizing Parthenium hysterophorus as a relatively cheap substrate. P. hysterophorus being a hazardous weed, its eradication is quite tedious. So, the utilization of the weed for useful purposes serves as a choice to overcome the problems posed by the weed. In the study, this weed has been successfully utilized as a substrate and the optimized fermentative production of biosurfactant was done. From one-factor-at a-time analysis it was known that the substrate level of 3% incubation time of 96 h, pH 6.0, temperature 35 °C, glucose and yeast extract was found to be the best C and N sources for a high yield. The extracted biosurfactant was partially purified and characterized using FTIR. The biosurfactant produced from the weed could help to render the milestone for distinct biomedical and other applications.
Topics: Biodegradation, Environmental; Fermentation; Plant Extracts; Surface-Active Agents; Temperature
PubMed: 31104258
DOI: 10.1007/s10532-019-09878-7 -
International Journal of Systematic and... Feb 2019A bacterial strain, designated WCHPs060039, was isolated from hospital sewage in China. The strain was Gram-stain-negative, obligate aerobic, flagellum-motile and...
A bacterial strain, designated WCHPs060039, was isolated from hospital sewage in China. The strain was Gram-stain-negative, obligate aerobic, flagellum-motile and positive for oxidase and catalase. A preliminary analysis of the 16S rRNA gene sequences indicated that strain WCHPs060039 belonged to the genus Pseudomonasand was closely related to members of the Pseudomonas putida group, with the highest similarities to Pseudomonas entomophila L48 (99.5 %), Pseudomonas mosselii CIP 105259 (99.52 %), Pseudomonas taiwanensis BCRC 17751 (99.45 %) and Pseudomonas plecoglossicida NBRC 103162 (99.31 %). Whole genome sequencing of the strain was performed. Phylogenetic analysis based on a set of core gene sequences revealed that the strain was distinct from its closest Pseudomonas species. Average nucleotide identity based on blast and in silico DNA-DNA hybridizationrevealed low genome relatedness to its closest Pseudomonas species (below the recommended thresholds of 95 and 70 %, respectively, for species delineation). The major fatty acids of the strain were 16:0, 17:0 cyclo, summed feature 3 (16:1ω7c/16:1ω6c and 16:1ω6c/16:1ω7c) and summed feature 8 (18:1ω7c). The ability to utilize inositol, sorbitol and d-glucuronic acid could differentiate strain WCHPs060039 from the closely related Pseudomonas species. It is therefore evident that strain WCHPs060039 represents a novel species of the genus Pseudomonas, for which the name Pseudomonas sichuanensis sp. nov. is proposed. The type strain is WCHPs060039 (GDMCC 1.1424=CNCTC 7662).
Topics: Bacterial Typing Techniques; Base Composition; China; DNA, Bacterial; Fatty Acids; Hospitals; Nucleic Acid Hybridization; Phylogeny; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sewage
PubMed: 30566068
DOI: 10.1099/ijsem.0.003188 -
Journal of Biotechnology Sep 2018Pseudomonas is a Gram-negative, rod-shaped bacteria. Many members of this genus displayed remarkable physiological and metabolic activity against different plant...
Pseudomonas is a Gram-negative, rod-shaped bacteria. Many members of this genus displayed remarkable physiological and metabolic activity against different plant pathogens. However, Pseudomonas mosselii has not yet been characterized in biocontrol against plant disease. Here we isolated a strain of P. mosselii BS011 from the rhizosphere soil of rice plants, and the isolate showed strong inhibitory activity against the rice blast fungus Magnaporthe oryzae. Further we sequenced the complete genome of BS011, which consist of 5.75 Mb with a circular chromosome, 5,170 protein-coding genes, 23 rRNA and 78 tRNA operons. Bioinformatic analysis revealed that seven gene clusters may be involved in the biosynthesis of metabolites. Gene deletion experiments demonstrated that the gene cluster c-xtl is required for inhibitory activity against M. oryzae. Bioassay showed that the crude extract from BS011 fermentation sample significantly inhibited the development of M. oryzae at a concentration of 10 μg/ml. Besides, we illustrated that the crude extract of BS011 impaired the appressorial formation in a dose dependent manner. Collectively our results revealed that P. mosselii BS011 is a promising biocontrol agent and the gene cluster c-xtl is essential for inhibiting the development of M. oryzae.
Topics: Biological Control Agents; Complex Mixtures; Fermentation; Genome, Bacterial; Magnaporthe; Multigene Family; Oryza; Phylogeny; Plant Diseases; Pseudomonas; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 29704539
DOI: 10.1016/j.jbiotec.2018.04.016 -
Journal of Environmental Management Apr 2018Response and growth kinetics of microbes in contaminated medium are useful indices for the screening and selection of tolerant species for eco-friendly bio-augmentative...
Response and growth kinetics of microbes in contaminated medium are useful indices for the screening and selection of tolerant species for eco-friendly bio-augmentative remediation of polluted environments. In this study, the heavy metal (HM) tolerance, bioaccumulation and growth kinetics of seven bacterial strains isolated from mining sites to 10 HMs (Cd, Hg, Ni, Al, Cr, Pb, Cu, Fe, Mn and Zn) at varied concentrations (25-600 mgL) were investigated. The isolates were phylogenetically (16S rRNA gene) related to Lysinibacillus macroides, Achromobacter spanius, Bacillus kochii, B. cereus, Klebsiella pneumoniae, Pseudomonas mosselii and P. nitroreducens. Metal tolerance, effects on lag phase duration and growth rates were assessed using the 96-well micro-titre method. Furthermore, metal bioaccumulation and quantities within cells were determined by transmission electron microscopy and electron dispersive x-ray analyses. Tolerance to Ni, Pb, Fe and Mn occurred at highest concentrations tested. Growth rates increased with increasing Fe concentrations, but reduced significantly (p < .05) with increasing Zn, Cu, Hg, Cd and Al. Significantly higher (p < .05) growth rates (compared to controls) was found with some isolates in Hg (25 mgL), Ni (100 mgL), Cr (150 mgL), Mn (600 mgL), Pb (100 mgL), Fe (600 mgL) and Al (50 mgL). Lag phase urations were isolate- and heavy metal-specific, in direct proportion to concentrations. A. spanius accumulated the most Mn and Zn, while B. cereus accumulated the most Cu. Metals accumulated intra-cellularly without cell morphology distortions. The isolates' multi-metal tolerance, intra-cellular metal bioaccumulation and growth kinetics suggest potentials for application in the synergetic biodegradation and bioremediation of polluted environments, especially HM-rich sites.
Topics: Bacteria; Environmental Monitoring; Gold; Kinetics; Metals, Heavy; Mining; RNA, Ribosomal, 16S
PubMed: 29454247
DOI: 10.1016/j.jenvman.2018.01.038 -
Bioscience, Biotechnology, and... Mar 2018Polyhydroxyalkanoates (PHAs) are biopolyesters produced by microorganisms that are environmentally friendly. PHAs can be used to replace traditional plastic to reduce...
Polyhydroxyalkanoates (PHAs) are biopolyesters produced by microorganisms that are environmentally friendly. PHAs can be used to replace traditional plastic to reduce environmental pollution in various fields. PHA production costs are high because PHA must be produced from a carbon substrate. The purpose of this study was to find the strain that can used the BDF by-product as the sole carbon source to produce high amounts of medium-chain-length PHA. Three isolates were evaluated for potential PHA production by using biodiesel-derived crude glycerol as the sole carbon source. Among them, Pseudomonas mosselii TO7 yielded high PHA content. The PHA produced from P. mosselii TO7 were medium-chain-length-PHAs. The PHA content of 48% cell dry weight in 48 h with a maximum PHA productivity of 13.16 mg PHAs L h. The narrow polydispersity index value of 1.3 reflected the homogeneity of the polymer chain, which was conducive to industrial applications.
Topics: Glycerol; Polyhydroxyalkanoates; Pseudomonas
PubMed: 29338575
DOI: 10.1080/09168451.2017.1422386 -
Frontiers in Microbiology 2017[This retracts the article on p. 1307 in vol. 7, PMID: 27617005.].
[This retracts the article on p. 1307 in vol. 7, PMID: 27617005.].
PubMed: 29204138
DOI: 10.3389/fmicb.2017.02363 -
Plant Biotechnology Journal Feb 2018The coleopteran insect western corn rootworm (WCR, Diabrotica virgifera virgifera) is an economically important pest in North America and Europe. Transgenic corn plants...
The coleopteran insect western corn rootworm (WCR, Diabrotica virgifera virgifera) is an economically important pest in North America and Europe. Transgenic corn plants producing Bacillus thuringiensis (Bt) insecticidal proteins have been useful against this devastating pest, but evolution of resistance has reduced their efficacy. Here, we report the discovery of a novel insecticidal protein, PIP-47Aa, from an isolate of Pseudomonas mosselii. PIP-47Aa sequence shows no shared motifs, domains or signatures with other known proteins. Recombinant PIP-47Aa kills WCR, two other corn rootworm pests (Diabrotica barberi and Diabrotica undecimpunctata howardi) and two other beetle species (Diabrotica speciosa and Phyllotreta cruciferae), but it was not toxic to the spotted lady beetle (Coleomegilla maculata) or seven species of Lepidoptera and Hemiptera. Transgenic corn plants expressing PIP-47Aa show significant protection from root damage by WCR. PIP-47Aa kills a WCR strain resistant to mCry3A and does not share rootworm midgut binding sites with mCry3A or AfIP-1A/1B from Alcaligenes that acts like Cry34Ab1/Cry35Ab1. Our results indicate that PIP-47Aa is a novel insecticidal protein for controlling the corn rootworm pests.
Topics: Animals; Bacillus thuringiensis; Pest Control, Biological; Plants, Genetically Modified; Zea mays
PubMed: 28796437
DOI: 10.1111/pbi.12806 -
Journal of Hazardous Materials Sep 2017Three bacterial strains capable of degrading phthalates namely Pseudomonas sp. PKDM2, Pseudomonas sp. PKDE1 and Pseudomonas sp. PKDE2 were isolated and characterized for...
Biodegradation of phthalic acid esters (PAEs) and in silico structural characterization of mono-2-ethylhexyl phthalate (MEHP) hydrolase on the basis of close structural homolog.
Three bacterial strains capable of degrading phthalates namely Pseudomonas sp. PKDM2, Pseudomonas sp. PKDE1 and Pseudomonas sp. PKDE2 were isolated and characterized for their degradative potential. These strains efficiently degraded 77.4%-84.4% of DMP, 75.0%-75.7% of DEP and 71.7%-74.7% of DEHP, initial amount of each phthalate is 500mgL of each phthalate, after 44h of incubation. GC-MS results reveal the tentative DEHP degradation pathway, where hydrolases mediate the breakdown of DEHP to phthalic acid (PA) via an intermediate MEHP. MEHP hydrolase is a serine hydrolase which is involved in the reduction of the MEHP to PA. The predicted 3D model of MEHP hydrolase from Pseudomonas mosselii was docked with phthalate monoesters (PMEs) such as MEHP, mono-n-hexyl phthalate (MHP), mono-n-butyl phthalate (MBP) and mono-n-ethyl phthalate (MEP), respectively. Docking results show the distance between the carbonyl carbon of respective phthalate monoester and the hydroxyl group of catalytic serine lies in the range of 2.9 to 3.3Å, which is similar to the ES complex of other serine hydrolases. This structural study highlights the interaction and the role of catalytic residues of MEHP hydrolase involved in the biodegradation of PMEs to phthalate.
Topics: Anti-Bacterial Agents; Biodegradation, Environmental; Catalytic Domain; Computer Simulation; Diethylhexyl Phthalate; Esters; Gas Chromatography-Mass Spectrometry; Hydrolases; Microbial Sensitivity Tests; Microscopy, Electron, Scanning; Molecular Docking Simulation; Molecular Structure; Pseudomonas; RNA, Ribosomal, 16S; Soil Pollutants; Species Specificity
PubMed: 28531656
DOI: 10.1016/j.jhazmat.2017.04.055 -
Genome Announcements Nov 2016Pseudomonas mosselii Gil3 was isolated from a catfish that survived from lethal challenge with hypervirulent Aeromonas hydrophila (vAh). When assayed in vitro, the...
Pseudomonas mosselii Gil3 was isolated from a catfish that survived from lethal challenge with hypervirulent Aeromonas hydrophila (vAh). When assayed in vitro, the bacterium showed antagonism against vAh. Sequence analysis revealed that the genome of P. mosselii Gil3 encodes numerous aromatic metabolism pathways and proteins for biosynthesis of antimicrobial compounds.
PubMed: 27856595
DOI: 10.1128/genomeA.01305-16