Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| isolation of polyvalent bacteriophages by sequential multiple-host approaches. | many studies on phage biology are based on isolation methods that may inadvertently select for narrow-host-range phages. consequently, broad-host-range phages, whose ecological significance is largely unexplored, are consistently overlooked. to enhance research on such polyvalent phages, we developed two sequential multihost isolation methods and tested both culture-dependent and culture-independent phage libraries for broad infectivity. lytic phages isolated from activated sludge were capable o ... | 2016 | 26590277 |
| mvat family proteins encoded on incp-7 plasmid pcar1 and the host chromosome regulate the host transcriptome cooperatively but differently. | mvat proteins are members of the h-ns family of proteins in pseudomonads. the incp-7 conjugative plasmid pcar1 carries an mvat-homologous gene, pmr. in pseudomonas putida kt2440 bearing pcar1, pmr and the chromosomally carried homologous genes, tura and turb, are transcribed at high levels, and pmr interacts with tura and turb in vitro. in the present study, we clarified how the three mvat proteins regulate the transcriptome of p. putida kt2440(pcar1). analyses performed by a modified chromatin ... | 2016 | 26590283 |
| substrate and cofactor range differences of two cysteine dioxygenases from ralstonia eutropha h16. | cysteine dioxygenases (cdos), which catalyze the sulfoxidation of cysteine to cysteine sulfinic acid (csa), have been extensively studied in eukaryotes because of their roles in several diseases. in contrast, only a few prokaryotic enzymes of this type have been investigated. in ralstonia eutropha h16, two cdo homologues (cdoa and cdob) have been identified previously. in vivo studies showed that escherichia coli cells expressing cdoa could convert 3-mercaptopropionate (3mp) to 3-sulfinopropiona ... | 2016 | 26590284 |
| use of substrate-induced gene expression in metagenomic analysis of an aromatic hydrocarbon-contaminated soil. | metagenomics allows the study of genes related to xenobiotic degradation in a culture-independent manner, but many of these studies are limited by the lack of genomic context for metagenomic sequences. this study combined a phenotypic screen known as substrate-induced gene expression (sigex) with whole-metagenome shotgun sequencing. sigex is a high-throughput promoter-trap method that relies on transcriptional activation of a green fluorescent protein (gfp) reporter gene in response to an induci ... | 2016 | 26590287 |
| genetically modified whole-cell bioreporters for environmental assessment. | living whole-cell bioreporters serve as environmental biosentinels that survey their ecosystems for harmful pollutants and chemical toxicants, and in the process act as human and other higher animal proxies to pre-alert for unfavorable, damaging, or toxic conditions. endowed with bioluminescent, fluorescent, or colorimetric signaling elements, bioreporters can provide a fast, easily measured link to chemical contaminant presence, bioavailability, and toxicity relative to a living system. though ... | 2013 | 26594130 |
| genome sequence and description of the anaerobic lignin-degrading bacterium tolumonas lignolytica sp. nov. | tolumonas lignolytica brl6-1(t) sp. nov. is the type strain of t. lignolytica sp. nov., a proposed novel species of the tolumonas genus. this strain was isolated from tropical rainforest soils based on its ability to utilize lignin as a sole carbon source. cells of tolumonas lignolytica brl6-1(t) are mesophilic, non-spore forming, gram-negative rods that are oxidase and catalase negative. the genome for this isolate was sequenced and returned in seven unique contigs totaling 3.6mbp, enabling the ... | 2015 | 26594307 |
| removal of 2-butoxyethanol gaseous emissions by biotrickling filtration packed with polyurethane foam. | the removal of 2-butoxyethanol from gaseous emissions was studied using two biotrickling filters (btf1 and btf2) packed with polyurethane foam. two different inoculum sources were used: a pure culture of pseudomonas sp. boe200 (btf1) and activated sludge from a municipal wastewater treatment plant (btf2). the bioreactors were operated at inlet loads (ils) of 130 and 195 g m(-3) hour(-1) and at an empty bed residence time (ebrt) of 12.5s. under an il of ∼130 g m(-3) hour(-1), btf1 presented highe ... | 2016 | 26596886 |
| integrative genomic mining for enzyme function to enable engineering of a non-natural biosynthetic pathway. | the ability to biosynthetically produce chemicals beyond what is commonly found in nature requires the discovery of novel enzyme function. here we utilize two approaches to discover enzymes that enable specific production of longer-chain (c5-c8) alcohols from sugar. the first approach combines bioinformatics and molecular modelling to mine sequence databases, resulting in a diverse panel of enzymes capable of catalysing the targeted reaction. the median catalytic efficiency of the computationall ... | 2015 | 26598135 |
| purification and characterization of a novel nad(p)+-farnesol dehydrogenase from polygonum minus leaves. | juvenile hormones have attracted attention as safe and selective targets for the design and development of environmentally friendly and biorational insecticides. in the juvenile hormone iii biosynthetic pathway, the enzyme farnesol dehydrogenase catalyzes the oxidation of farnesol to farnesal. in this study, farnesol dehydrogenase was extracted from polygonum minus leaves and purified 204-fold to apparent homogeneity by ion-exchange chromatography using deae-toyopearl, sp-toyopearl, and super-q ... | 2015 | 26600471 |
| chemotaxis increases the residence time of bacteria in granular media containing distributed contaminant sources. | the use of chemotactic bacteria in bioremediation has the potential to increase access to, and the biotransformation of, contaminant mass within the subsurface. this laboratory-scale study aimed to understand and quantify the influence of chemotaxis on the residence times of pollutant-degrading bacteria within homogeneous treatment zones. focus was placed on a continuous-flow sand-packed column in which a uniform distribution of naphthalene crystals created distributed sources of dissolved-phase ... | 2016 | 26605857 |
| epidemiologic and genotypic review of carbapenemase-producing organisms in british columbia, canada, between 2008 and 2014. | carbapenemase-producing organisms (cpos) are a serious emerging problem for health care facilities worldwide. owing to their resistance to most antimicrobial therapies, cpos are difficult to treat and pose a challenge for infection prevention and control. since 2010, lab-based surveillance for cpos and pcr-based testing were implemented in british columbia (bc), canada. a review of cpos in bc from 2008 to march 2014 was done to characterize the resistance mechanisms and possible clonal strain tr ... | 2016 | 26607987 |
| a novel biocatalyst for efficient production of 2-oxo-carboxylates using glycerol as the cost-effective carbon source. | the surplus of glycerol has increased remarkably as a main byproduct during the biofuel's production. exploiting an alternative route for glycerol utilization is significantly important for sustainability of biofuels. | 2015 | 26609321 |
| protective role of glycerol against benzene stress: insights from the pseudomonas putida proteome. | chemical activities of hydrophobic substances can determine the windows of environmental conditions over which microbial systems function and the metabolic inhibition of microorganisms by benzene and other hydrophobes can, paradoxically, be reduced by compounds that protect against cellular water stress (bhaganna et al. in microb biotechnol 3:701-716, 2010; cray et al. in curr opin biotechnol 33:228-259, 2015a). we hypothesized that this protective effect operates at the macromolecule structure- ... | 2016 | 26612269 |
| integrated micro-biochemical approach for phytoremediation of cadmium and lead contaminated soils using gladiolus grandiflorus l cut flower. | the potential of vermicompost, elemental sulphur, thiobacillus thiooxidans and pseudomonas putida for phytoremediation is well known individually but their integrated approach has not been discovered so far. the present work highlights the consideration of so far overlooked aspects of their integrated treatment by growing the ornamental plant, gladiolus grandiflorus l in uncontaminated and sewage-contaminated soils (sulphur-deficient alluvial entisols, ph 7.6-7.8) for phytoremediation of cadmium ... | 2016 | 26615479 |
| the catalytic mechanism of decarboxylative hydroxylation of salicylate hydroxylase revealed by crystal structure analysis at 2.5 å resolution. | the x-ray crystal structure of a salicylate hydroxylase from pseudomonas putida s-1 complexed with coenzyme fad has been determined to a resolution of 2.5 å. structural conservation with p- or m-hydroxybenzoate hydroxylase is very good throughout the topology, despite a low amino sequence identity of 20-40% between these three hydroxylases. salicylate hydroxylase is composed of three distinct domains and includes fad between domains i and ii, which is accessible to solvent. in this study, which ... | 2016 | 26616054 |
| metabolic engineering of pseudomonas putida for production of docosahexaenoic acid based on a myxobacterial pufa synthase. | long-chain polyunsaturated fatty acids (lc-pufas) can be produced de novo via polyketide synthase-like enzymes known as pufa synthases, which are encoded by pfa biosynthetic gene clusters originally discovered from marine microorganisms. recently similar gene clusters were detected and characterized in terrestrial myxobacteria revealing several striking differences. as the identified myxobacterial producers are difficult to handle genetically and grow very slowly we aimed to establish heterologo ... | 2016 | 26617065 |
| genetic programming of catalytic pseudomonas putida biofilms for boosting biodegradation of haloalkanes. | bacterial biofilms outperform planktonic counterparts in whole-cell biocatalysis. the transition between planktonic and biofilm lifestyles of the platform strain pseudomonas putida kt2440 is ruled by a regulatory network controlling the levels of the trigger signal cyclic di-gmp (c-di-gmp). this circumstance was exploited for designing a genetic device that over-runs the synthesis or degradation of c-di-gmp--thus making p. putida to form biofilms at user's will. for this purpose, the transcripti ... | 2016 | 26620533 |
| characterization of a carbapenem-hydrolyzing enzyme, poxb, in pseudomonas aeruginosa pao1. | pseudomonas aeruginosa is an opportunistic pathogen often associated with severe and life-threatening infections that are highly impervious to treatment. this microbe readily exhibits intrinsic and acquired resistance to varied antimicrobial drugs. resistance to penicillin-like compounds is commonplace and provided by the chromosomal ampc β-lactamase. a second, chromosomally encoded β-lactamase, poxb, has previously been reported in p. aeruginosa. in the present work, the contribution of this cl ... | 2016 | 26621621 |
| isolation and characterization of two novel halotolerant catechol 2, 3-dioxygenases from a halophilic bacterial consortium. | study of enzymes in halophiles will help to understand the mechanism of aromatic hydrocarbons degradation in saline environment. in this study, two novel catechol 2,3-dioxygenases (c23o1 and c23o2) were cloned and overexpressed from a halophilic bacterial consortium enriched from an oil-contaminated saline soil. phylogenetic analysis indicated that the novel c23os and their relatives formed a new branch in subfamily i.2.a of extradiol dioxygenases and the sequence differences were further analyz ... | 2015 | 26621792 |
| non-pathogenic microflora of a spring water with regenerative properties. | the comano spring water (comano, italy) has been demonstrated to improve skin regeneration, not only by increasing keratinocyte proliferation and migration, but also by modulating the regenerated collagen and elastic fibers in the dermis. however, such biological properties may not be entirely explained by its mineral composition only. as the non-pathogenic bacterial populations have demonstrated an active role in different biological processes, the potential presence of non-pathogenic bacterial ... | 2015 | 26623012 |
| metabolic engineering of acinetobacter baylyi adp1 for removal of clostridium butyricum growth inhibitors produced from lignocellulosic hydrolysates. | pretreatment of lignocellulosic biomass can produce inhibitory compounds that are harmful for microorganisms used in the production of biofuels and other chemicals from lignocellulosic sugars. selective inhibitor removal can be achieved with biodetoxification where microorganisms catabolize the inhibitors without consuming the sugars. we engineered the strictly aerobic acinetobacter baylyi adp1 for detoxification of lignocellulosic hydrolysates by removing the gene for glucose dehydrogenase, gcd ... | 2015 | 26628912 |
| individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology. | for bacteria, replication mainly involves growth by binary fission. however, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. they thereby evade detection by conventional culture-based methods. such dormant cells may also be observed in laboratory cultures and in clinical microbiology. they are usually more tolerant to s ... | 2015 | 26629334 |
| overflow metabolism in escherichia coli results from efficient proteome allocation. | overflow metabolism refers to the seemingly wasteful strategy in which cells use fermentation instead of the more efficient respiration to generate energy, despite the availability of oxygen. known as the warburg effect in the context of cancer growth, this phenomenon occurs ubiquitously for fast-growing cells, including bacteria, fungi and mammalian cells, but its origin has remained unclear despite decades of research. here we study metabolic overflow in escherichia coli, and show that it is a ... | 2015 | 26632588 |
| enhanced retention of chemotactic bacteria in a pore network with residual napl contamination. | nonaqueous-phase liquid (napl) contaminants are difficult to eliminate from natural aquifers due, in part, to the heterogeneous structure of the soil. chemotaxis enhances the mixing of bacteria with contaminant sources in low-permeability regions, which may not be readily accessible by advection and dispersion alone. a microfluidic device was designed to mimic heterogeneous features of a contaminated groundwater aquifer. napl droplets (toluene) were trapped within a fine pore network, and bacter ... | 2016 | 26633578 |
| characterization of pseudooxynicotine amine oxidase of pseudomonas putida s16 that is crucial for nicotine degradation. | pseudooxynicotine amine oxidase (pnao) is essential to the pyrrolidine pathway of nicotine degradation of pseudomonas putida strain s16, which is significant for the detoxification of nicotine, through removing the ch3nh2 group. however, little is known about biochemical mechanism of this enzyme. here, we characterized its properties and biochemical mechanism. isotope labeling experiments provided direct evidence that the newly introduced oxygen atom in 3-succinoylsemialdehyde-pyridine is derive ... | 2015 | 26634650 |
| pseudomonads rule degradation of polyaromatic hydrocarbons in aerated sediment. | given that the degradation of aromatic pollutants in anaerobic environments such as sediment is generally very slow, aeration could be an efficient bioremediation option. using stable isotope probing (sip) coupled with pyrosequencing analysis of 16s rrna genes, we identified naphthalene-utilizing populations in aerated polyaromatic hydrocarbon (pah)-polluted sediment. the results showed that naphthalene was metabolized at both 10 and 20°c following oxygen delivery, with increased degradation at ... | 2015 | 26635740 |
| antibacterial activity of stenotrophomonas maltophilia endolysin p28 against both gram-positive and gram-negative bacteria. | maltocin p28 is a phage-tail like bacteriocin produced by stenotrophomonas maltophilia p28. the orf8 of maltocin p28 gene cluster is predicted to encode an endolysin and we name it endolysin p28. sequence analysis revealed that it contains the lysozyme_like superfamily conserved domain. endolysin p28 has the four consensus motifs as that of escherichia coli phage lambda gpr. in this study, endolysin p28 was expressed in e. coli bl21 (de3) and purified with a c-terminal oligo-histidine tag. the a ... | 2015 | 26635765 |
| metabolic engineering of pseudomonas putida kt2440 to produce anthranilate from glucose. | the pseudomonas putida kt2440 strain was engineered in order to produce anthranilate (oab, ortho-aminobenzoate), a precursor of the aromatic amino acid tryptophan, from glucose as sole carbon source. to enable the production of the metabolic intermediate oab, the trpdc operon encoding an anthranilate phosphoribosyltransferase (trpd) and an indole-3-glycerol phosphate synthase (trpc), were deleted. in addition, the chorismate mutase (phea) responsible for the conversion of chorismate over prephen ... | 2015 | 26635771 |
| water stress responses of tomato mutants impaired in hormone biosynthesis reveal abscisic acid, jasmonic acid and salicylic acid interactions. | to investigate the putative crosstalk between ja and aba in solanum lycopersicum plants in response to drought, suppressor of prosystemin-mediated responses2 (spr2, ja-deficient) and flacca (flc, aba-deficient) mutants together with the naphthalene/salicylate hydroxylase (nahg) transgenic (sa-deficient) line were used. hormone profiling and gene expression of key enzymes in aba, ja and sa biosynthesis were analyzed during early stages of drought. aba accumulation was comparable in spr2 and wild ... | 2015 | 26635826 |
| transcription factor levels enable metabolic diversification of single cells of environmental bacteria. | transcriptional noise is a necessary consequence of the molecular events that drive gene expression in prokaryotes. however, some environmental microorganisms that inhabit polluted sites, for example, the m-xylene degrading soil bacterium pseudomonas putida mt-2 seem to have co-opted evolutionarily such a noise for deploying a metabolic diversification strategy that allows a cautious exploration of new chemical landscapes. we have examined this phenomenon under the light of deterministic and sto ... | 2016 | 26636554 |
| novel rhizosphere soil alleles for the enzyme 1-aminocyclopropane-1-carboxylate deaminase queried for function with an in vivo competition assay. | metagenomes derived from environmental microbiota encode a vast diversity of protein homologs. how this diversity impacts protein function can be explored through selection assays aimed to optimize function. while artificially generated gene sequence pools are typically used in selection assays, their usage may be limited because of technical or ethical reasons. here, we investigate an alternative strategy, the use of soil microbial dna as a starting point. we demonstrate this approach by optimi ... | 2016 | 26637602 |
| optical sensing of microbial life on surfaces. | the label-free detection of microbial cells attached to a surface is an active field of research. the field is driven by the need to understand and control the growth of biofilms in a number of applications, including basic research in natural environments, industrial facilities, and clinical devices, to name a few. despite significant progress in the ability to monitor the growth of biofilms and related living cells, the sensitivity and selectivity of such sensors are still a challenge. we beli ... | 2016 | 26637605 |
| interactions of eps with soil minerals: a combination study by itc and clsm. | the adsorption of extracellular polymeric substances (eps) from pseudomonas putida on montmorillonite, kaolinite and goethite was investigated as a function of ph using batch studies coupled with confocal laser scanning microscopy (clsm) and isothermal titration calorimetry (itc). characterization by raman spectroscopy, x-ray photoelectron spectroscopy (xps) and fourier transform infrared (ftir) spectroscopy showed that the extracted eps contained carboxyl, phosphoryl, amino, and hydroxyl on fun ... | 2016 | 26638177 |
| ustilago maydis produces itaconic acid via the unusual intermediate trans-aconitate. | itaconic acid is an important biomass-derived chemical building block but has also recently been identified as a metabolite produced in mammals, which has antimicrobial activity. the biosynthetic pathway of itaconic acid has been elucidated in the ascomycetous fungus aspergillus terreus and in human macrophages. in both organisms itaconic acid is generated by decarboxylation of the tricarboxylic acid (tca) cycle intermediate cis-aconitate. here, we show that the basidiomycetous fungus ustilago m ... | 2015 | 26639528 |
| ustilago maydis produces itaconic acid via the unusual intermediate trans-aconitate. | itaconic acid is an important biomass-derived chemical building block but has also recently been identified as a metabolite produced in mammals, which has antimicrobial activity. the biosynthetic pathway of itaconic acid has been elucidated in the ascomycetous fungus aspergillus terreus and in human macrophages. in both organisms itaconic acid is generated by decarboxylation of the tricarboxylic acid (tca) cycle intermediate cis-aconitate. here, we show that the basidiomycetous fungus ustilago m ... | 2015 | 26639528 |
| classification and taxonomy of vegetable macergens. | macergens are bacteria capable of releasing pectic enzymes (pectolytic bacteria). these enzymatic actions result in the separation of plant tissues leading to total plant destruction. this can be attributed to soft rot diseases in vegetables. these macergens primarily belong to the genus erwinia and to a range of opportunistic pathogens namely: the xanthomonas spp., pseudomonas spp., clostridium spp., cytophaga spp., and bacillus spp. they consist of taxa that displayed considerable heterogeneit ... | 2015 | 26640465 |
| 'deadman' and 'passcode' microbial kill switches for bacterial containment. | biocontainment systems that couple environmental sensing with circuit-based control of cell viability could be used to prevent escape of genetically modified microbes into the environment. here we present two engineered safeguard systems known as the 'deadman' and 'passcode' kill switches. the deadman kill switch uses unbalanced reciprocal transcriptional repression to couple a specific input signal with cell survival. the passcode kill switch uses a similar two-layered transcription design and ... | 2015 | 26641934 |
| 'deadman' and 'passcode' microbial kill switches for bacterial containment. | biocontainment systems that couple environmental sensing with circuit-based control of cell viability could be used to prevent escape of genetically modified microbes into the environment. here we present two engineered safeguard systems known as the 'deadman' and 'passcode' kill switches. the deadman kill switch uses unbalanced reciprocal transcriptional repression to couple a specific input signal with cell survival. the passcode kill switch uses a similar two-layered transcription design and ... | 2015 | 26641934 |
| a method for rapid quantitative assessment of biofilms with biomolecular staining and image analysis. | the accumulation of bacteria in surface-attached biofilms can be detrimental to human health, dental hygiene, and many industrial processes. natural biofilms are soft and often transparent, and they have heterogeneous biological composition and structure over micro- and macroscales. as a result, it is challenging to quantify the spatial distribution and overall intensity of biofilms. in this work, a new method was developed to enhance the visibility and quantification of bacterial biofilms. firs ... | 2015 | 26643074 |
| a method for rapid quantitative assessment of biofilms with biomolecular staining and image analysis. | the accumulation of bacteria in surface-attached biofilms can be detrimental to human health, dental hygiene, and many industrial processes. natural biofilms are soft and often transparent, and they have heterogeneous biological composition and structure over micro- and macroscales. as a result, it is challenging to quantify the spatial distribution and overall intensity of biofilms. in this work, a new method was developed to enhance the visibility and quantification of bacterial biofilms. firs ... | 2015 | 26643074 |
| hexr controls glucose-responsive genes and central carbon metabolism in neisseria meningitidis. | neisseria meningitidis, an exclusively human pathogen and the leading cause of bacterial meningitis, must adapt to different host niches during human infection. n. meningitidis can utilize a restricted range of carbon sources, including lactate, glucose, and pyruvate, whose concentrations vary in host niches. microarray analysis of n. meningitidis grown in a chemically defined medium in the presence or absence of glucose allowed us to identify genes regulated by carbon source availability. most ... | 2016 | 26644430 |
| structural insight into how bacteria prevent interference between multiple divergent type iv secretion systems. | prokaryotes use type iv secretion systems (t4sss) to translocate substrates (e.g., nucleoprotein, dna, and protein) and/or elaborate surface structures (i.e., pili or adhesins). bacterial genomes may encode multiple t4sss, e.g., there are three functionally divergent t4sss in some bartonella species (vir, vbh, and trw). in a unique case, most rickettsial species encode a t4ss (rvh) enriched with gene duplication. within single genomes, the evolutionary and functional implications of cross-system ... | 2015 | 26646013 |
| discrimination between bacterial species by ratiometric analysis of their carbohydrate binding profile. | antibiotic resistance is a global health concern meaning there is an urgent need for new treatments and diagnostics. here glycosylated surfaces are used to profile the binding patterns of a range of gram-negative, gram-positive and mycobacteria. this enables the creation of 'barcodes' to enable identification and discrimination between the strains, which could not be achieved by single-point glycan binding and offers a new concept in bacteria detection. | 2015 | 26647648 |
| discrimination between bacterial species by ratiometric analysis of their carbohydrate binding profile. | antibiotic resistance is a global health concern meaning there is an urgent need for new treatments and diagnostics. here glycosylated surfaces are used to profile the binding patterns of a range of gram-negative, gram-positive and mycobacteria. this enables the creation of 'barcodes' to enable identification and discrimination between the strains, which could not be achieved by single-point glycan binding and offers a new concept in bacteria detection. | 2015 | 26647648 |
| bacterial colonies in solid media and foods: a review on their growth and interactions with the micro-environment. | bacteria, either indigenous or added, are immobilized in solid foods where they grow as colonies. since the 80's, relatively few research groups have explored the implications of bacteria growing as colonies and mostly focused on pathogens in large colonies on agar/gelatine media. it is only recently that high resolution imaging techniques and biophysical characterization techniques increased the understanding of the growth of bacterial colonies, for different sizes of colonies, at the microscop ... | 2015 | 26648910 |
| oprg harnesses the dynamics of its extracellular loops to transport small amino acids across the outer membrane of pseudomonas aeruginosa. | oprg is an outer membrane protein of pseudomonas aeruginosa whose function as an antibiotic-sensitive porin has been controversial and not well defined. circumstantial evidence led to the proposal that oprg might transport hydrophobic compounds by using a lateral gate in the barrel wall thought to be lined by three conserved prolines. to test this hypothesis and to find the physiological substrates of oprg, we reconstituted the purified protein into liposomes and found it to facilitate the trans ... | 2015 | 26655471 |
| a 2-hydroxypyridine catabolism pathway in rhodococcus rhodochrous strain py11. | rhodococcus rhodochrous py11 (dsm 101666) is able to use 2-hydroxypyridine as a sole source of carbon and energy. by investigating a gene cluster (hpo) from this bacterium, we were able to reconstruct the catabolic pathway of 2-hydroxypyridine degradation. here, we report that in rhodococcus rhodochrous py11, the initial hydroxylation of 2-hydroxypyridine is catalyzed by a four-component dioxygenase (hpobcdf). a product of the dioxygenase reaction (3,6-dihydroxy-1,2,3,6-tetrahydropyridin-2-one) ... | 2016 | 26655765 |
| defining the metabolic functions and roles in virulence of the rpon1 and rpon2 genes in ralstonia solanacearum gmi1000. | the alternative sigma factor rpon is a unique regulator found among bacteria. it controls numerous processes that range from basic metabolism to more complex functions such as motility and nitrogen fixation. our current understanding of rpon function is largely derived from studies on prototypical bacteria such as escherichia coli. bacillus subtilis and pseudomonas putida. although the extent and necessity of rpon-dependent functions differ radically between these model organisms, each bacterium ... | 2015 | 26659655 |
| assessment of the contribution of chemoreceptor-based signalling to biofilm formation. | although it is well established that one- and two-component regulatory systems participate in regulating biofilm formation, there also exists evidence suggesting that chemosensory pathways are also involved. however, little information exists about which chemoreceptors and signals modulate this process. here we report the generation of the complete set of chemoreceptor mutants of pseudomonas putida kt2440 and the identification of four mutants with significantly altered biofilm phenotypes. these ... | 2016 | 26662997 |
| phylogenetic analysis based evolutionary study of 16s rrna in known pseudomonas sp. | molecular evolution analysis of 16s rrna sequences of native pseudomonas strains and different fluorescent pseudomonads were conducted on the basis of molecular evolutionary genetics analysis version 5.2 (mega5.2). topological evaluations show common origin for native strains with other known strains with available sequences at genbank database. phylogenetic affiliation of different pseudomonas sp based on 16s rrna gene shows that molecular divergence contributes to the genetic diversity of pseu ... | 2015 | 26664032 |
| active site diversification of p450cam with indole generates catalysts for benzylic oxidation reactions. | cytochrome p450 monooxygenases are useful biocatalysts for c-h activation, and there is a need to expand the range of these enzymes beyond what is naturally available. a panel of 93 variants of active self-sufficient p450cam[tyr96phe]-rhfred fusion enzymes with a broad diversity in active site amino acids was developed by screening a large mutant library of 16,500 clones using a simple, highly sensitive colony-based colorimetric screen against indole. these mutants showed distinct fingerprints o ... | 2015 | 26664590 |
| production of fatty acids in ralstonia eutropha h16 by engineering β-oxidation and carbon storage. | ralstonia eutropha h16 is a facultatively autotrophic hydrogen-oxidizing bacterium capable of producing polyhydroxybutyrate (phb)-based bioplastics. as phb's physical properties may be improved by incorporation of medium-chain-length fatty acids (mcfas), and mcfas are valuable on their own as fuel and chemical intermediates, we engineered r. eutropha for mcfa production. expression of ucfatb2, a medium-chain-length-specific acyl-acp thioesterase, resulted in production of 14 mg/l laurate in wild ... | 2015 | 26664804 |
| stability of the graa antitoxin depends on growth phase, atp level, and global regulator mext. | bacterial type ii toxin-antitoxin systems consist of a potentially poisonous toxin and an antitoxin that inactivates the toxic protein by binding to it. most of the toxins regulate stress survival, but their activation depends on the stability of the antitoxin that has to be degraded in order for the toxin to be able to attack its cellular targets. the degradation of antitoxins is usually rapid and carried out by atp-dependent protease lon or clp, which is activated under stress conditions. the ... | 2016 | 26668267 |
| immobilization of microbes for bioremediation of crude oil polluted environments: a mini review. | petroleum hydrocarbons are the most common environmental pollutants in the world and oil spills pose a great hazard to terrestrial and marine ecosystems. oil pollution may arise either accidentally or operationally whenever oil is produced, transported, stored and processed or used at sea or on land. oil spills are a major menace to the environment as they severely damage the surrounding ecosystems. to improve the survival and retention of the bioremediation agents in the contaminated sites, bac ... | 2015 | 26668662 |
| biotechnological production of 1,2,4-butanetriol: an efficient process to synthesize energetic material precursor from renewable biomass. | 1,2,4-butanetriol (bt) is a valuable chemical with extensive applications in many different fields. the traditional chemical routes to synthesize bt suffer from many drawbacks, e.g., harsh reaction conditions, multiple steps and poor selectivity, limiting its industrial production. in this study, an engineered escherichia coli strain was constructed to produce bt from xylose, which is a major component of the lignocellulosic biomass. through the coexpression of a xylose dehydrogenase (ccxylb) an ... | 2015 | 26670289 |
| on-chip cell lysis by antibacterial non-leaching reusable quaternary ammonium monolithic column. | reusable antibacterial non-leaching monolithic columns polymerized in microfluidic channels designed for on-chip cell lysis applications were obtained by the photoinitiated free radical copolymerization of diallyldimethylammonium chloride (dadmac) and ethylene glycol diacrylate (egda) in the presence of a porogenic solvent. the microfluidic channels were fabricated in cross-linked poly(methyl methacrylate) (x-pmma) substrates by laser micromachining. the monolithic columns have the ability to in ... | 2016 | 26671610 |
| a functional 4-hydroxybenzoate degradation pathway in the phytopathogen xanthomonas campestris is required for full pathogenicity. | plants contain significant levels of natural phenolic compounds essential for reproduction and growth, as well as defense mechanisms against pathogens. xanthomonas campestris pv. campestris (xcc) is the causal agent of crucifers black rot. here we showed that genes required for the synthesis, utilization, transportation, and degradation of 4-hydroxybenzoate (4-hba) are present in xcc. xcc rapidly degrades 4-hba, but has no effect on 2-hydroxybenzoate and 3-hydroxybenzoate when grown in xoln medi ... | 2015 | 26672484 |
| mutational and acquired carbapenem resistance mechanisms in multidrug resistant pseudomonas aeruginosa clinical isolates from recife, brazil. | an investigation was carried out into the genetic mechanisms responsible for multidrug resistance in nine carbapenem-resistant pseudomonas aeruginosa isolates from different hospitals in recife, brazil. susceptibility to antimicrobial agents was determined by broth microdilution. polymerase chain reaction (pcr) was employed to detect the presence of genes encoding β-lactamases, aminoglycoside-modifying enzymes (ames), 16s rrna methylases, integron-related genes and oprd. expression of genes codi ... | 2015 | 26676375 |
| genetic characterization of a novel bladim-2-carrying megaplasmid p12969-dim from clinical pseudomonas putida. | to characterize a bladim-2-carrying 409 kb megaplasmid p12969-dim of pseudomonas putida 12969 from a patient with pneumonia in china. | 2016 | 26679251 |
| iron oxide nanoparticle-mediated hyperthermia stimulates dispersal in bacterial biofilms and enhances antibiotic efficacy. | the dispersal phase that completes the biofilm lifecycle is of particular interest for its potential to remove recalcitrant, antimicrobial tolerant biofilm infections. here we found that temperature is a cue for biofilm dispersal and a rise by 5 °c or more can induce the detachment of pseudomonas aeruginosa biofilms. temperature upshifts were found to decrease biofilm biomass and increase the number of viable freely suspended cells. the dispersal response appeared to involve the secondary messen ... | 2015 | 26681339 |
| genetic analysis reveals the essential role of nitrogen phosphotransferase system components in sinorhizobium fredii ccbau 45436 symbioses with soybean and pigeonpea plants. | the nitrogen phosphotransferase system (pts(ntr)) consists of ei(ntr), npr, and eiia(ntr). the active phosphate moiety derived from phosphoenolpyruvate is transferred through ei(ntr) and npr to eiia(ntr). sinorhizobium fredii can establish a nitrogen-fixing symbiosis with the legume crops soybean (as determinate nodules) and pigeonpea (as indeterminate nodules). in this study, s. fredii strains with mutations in ptsp and ptso (encoding ei(ntr) and npr, respectively) formed ineffective nodules on ... | 2016 | 26682851 |
| fed-batch production of poly-3-hydroxydecanoate from decanoic acid. | decanoic acid is an ideal substrate for the synthesis of medium-chain-length poly-3-hydroxyalkanoate (mcl-pha), but its use for this purpose has only previously been studied in shake-flasks likely due to its surfactant properties, low aqueous solubility and high melting temperature. a fed-batch fermentation process was developed for the production of mcl-pha from decanoic acid using pseudomonas putida kt2440. decanoic acid was kept in liquid form by heating or by mixing with acetic acid to preve ... | 2016 | 26689481 |
| characterization of thermotolerant chitinases encoded by a brevibacillus laterosporus strain isolated from a suburban wetland. | to isolate and characterize chitinases that can be applied with practical advantages, 57 isolates of chitin-degrading bacteria were isolated from the soil of a suburban wetland. 16s rrna gene analysis revealed that the majority of these strains belonged to two genera, paenibacillus and brevibacillus. taking thermostability into account, the chitinases (chia and chic) of a b. laterosporus strain were studied further. ni-nta affinity-purified chia and chic were optimally active at ph 7.0 and 6.0, ... | 2015 | 26690223 |
| exacerbation of substrate toxicity by iptg in escherichia coli bl21(de3) carrying a synthetic metabolic pathway. | heterologous expression systems based on promoters inducible with isopropyl-β-d-1-thiogalactopyranoside (iptg), e.g., escherichia coli bl21(de3) and cognate laci(q)/p(lacuv5)-t7 vectors, are commonly used for production of recombinant proteins and metabolic pathways. the applicability of such cell factories is limited by the complex physiological burden imposed by overexpression of the exogenous genes during a bioprocess. this burden originates from a combination of stresses that may include com ... | 2015 | 26691337 |
| purification, characterization of l-methioninase from candida tropicalis, and its application as an anticancer. | the aim of the present study is to purify l-methioninase from candida tropicalis 34.19-fold with 27.98% recovery after ion exchange chromatography followed by gel filtration. the purified enzyme revealed a single band on sds-page gel with a molecular weight of 46 kda. its optimum temperature was 45 to 55 and thermal stability was 55°c for 15 min. the enzyme had optimum ph at 6.5 and stability at a ph range of 5.5 to 7.0 for 24 hr. the maximum activity was observed with substrate concentration of ... | 2015 | 26691554 |
| direct conversion of theophylline to 3-methylxanthine by metabolically engineered e. coli. | methylxanthines are natural and synthetic compounds found in many foods, drinks, pharmaceuticals, and cosmetics. aside from caffeine, production of many methylxanthines is currently performed by chemical synthesis. this process utilizes many chemicals, multiple reactions, and different reaction conditions, making it complicated, environmentally dissatisfactory, and expensive, especially for monomethylxanthines and paraxanthine. a microbial platform could provide an economical, environmentally fr ... | 2015 | 26691652 |
| a flagellar glycan-specific protein encoded by campylobacter phages inhibits host cell growth. | we previously characterized a carbohydrate binding protein, gp047, derived from lytic campylobacter phage nctc 12673, as a promising diagnostic tool for the identification of campylobacter jejuni and campylobacter coli. we also demonstrated that this protein binds specifically to acetamidino-modified pseudaminic acid residues on host flagella, but the role of this protein in the phage lifecycle remains unknown. here, we report that gp047 is capable of inhibiting c. jejuni growth both on solid an ... | 2015 | 26694450 |
| bacterial exchange in household washing machines. | household washing machines (wms) launder soiled clothes and textiles, but do not sterilize them. we investigated the microbial exchange occurring in five household wms. samples from a new cotton t-shirt were laundered together with a normal laundry load. analyses were performed on the influent water and the ingoing cotton samples, as well as the greywater and the washed cotton samples. the number of living bacteria was generally not lower in the wm effluent water as compared to the influent water. ... | 2015 | 26696989 |
| phosphorus and compost management influence maize (zea mays) productivity under semiarid condition with and without phosphate solubilizing bacteria. | phosphorus (p) unavailability and lack of organic matter in the soils under semiarid climates are the two major constraints for low crop productivity. field trial was conducted to study the effects of p levels, compost application times and seed inoculation with phosphate solubilizing bacteria (psb) on the yield and yield components of maize (zea mays l., cv. azam). the experiment was conducted at the agronomy research farm of the university of agriculture peshawar-pakistan during summer 2014. t ... | 2015 | 26697038 |
| indirect manganese removal by stenotrophomonas sp. and lysinibacillus sp. isolated from brazilian mine water. | manganese is a contaminant in the wastewaters produced by brazilian mining operations, and the removal of the metal is notoriously difficult because of the high stability of the mn(ii) ion in aqueous solutions. to explore a biological approach for removing excessive amounts of aqueous mn(ii), we investigated the potential of mn(ii) oxidation by both consortium and bacterial isolates from a brazilian manganese mine. a bacterial consortium was able to remove 99.7% of the mn(ii). a phylogenetic ana ... | 2015 | 26697496 |
| prevalence and antimicrobial resistance of microbes causing bloodstream infections in unguja, zanzibar. | bloodstream infections (bsi) are frequent and cause high case-fatality rates. urgent antibiotic treatment can save patients' lives, but antibiotic resistance can render antibiotic therapy futile. this study is the first to collect epidemiological data on bsi from unguja, zanzibar. | 2015 | 26700032 |
| quantifying nad(p)h production in the upper entner-doudoroff pathway from pseudomonas putida kt2440. | despite the lack of biochemical information, all available in silico metabolic models of pseudomonas putida kt2440 consider nadp as the only cofactor accepted by the glucose-6-phosphate dehydrogenases. because the entner-doudoroff pathway is the main glycolytic route in this bacterium, determining how much nadh and nadph are produced in the reaction catalyzed by these enzymes is very important for the correct interpretation of metabolic flux distributions. to determine the actual cofactor prefer ... | 2015 | 26702395 |
| two-step bioleaching of copper and gold from discarded printed circuit boards (pcb). | an effective strategy for environmentally sound biological recovery of copper and gold from discarded printed circuit boards (pcb) in a two-step bioleaching process was experimented. in the first step, chemolithotrophic acidophilic acidithiobacillus ferrivorans and acidithiobacillus thiooxidans were used. in the second step, cyanide-producing heterotrophic pseudomonas fluorescens and pseudomonas putida were used. results showed that at a 1% pulp density (10g/l pcb concentration), 98.4% of the co ... | 2016 | 26704063 |
| mechanistic insights into c-di-gmp-dependent control of the biofilm regulator fleq from pseudomonas aeruginosa. | bacterial biofilm formation during chronic infections confers increased fitness, antibiotic tolerance, and cytotoxicity. in many pathogens, the transition from a planktonic lifestyle to collaborative, sessile biofilms represents a regulated process orchestrated by the intracellular second-messenger c-di-gmp. a main effector for c-di-gmp signaling in the opportunistic pathogen pseudomonas aeruginosa is the transcription regulator fleq. fleq is a bacterial enhancer-binding protein (bebp) with a ce ... | 2016 | 26712005 |
| mechanistic insights into c-di-gmp-dependent control of the biofilm regulator fleq from pseudomonas aeruginosa. | bacterial biofilm formation during chronic infections confers increased fitness, antibiotic tolerance, and cytotoxicity. in many pathogens, the transition from a planktonic lifestyle to collaborative, sessile biofilms represents a regulated process orchestrated by the intracellular second-messenger c-di-gmp. a main effector for c-di-gmp signaling in the opportunistic pathogen pseudomonas aeruginosa is the transcription regulator fleq. fleq is a bacterial enhancer-binding protein (bebp) with a ce ... | 2016 | 26712005 |
| maldi-tof mass spectrometry: a powerful tool for clinical microbiology at hôpital principal de dakar, senegal (west africa). | our team in europe has developed the routine clinical laboratory identification of microorganisms by matrix-assisted laser desorption ionization time-of-flight (maldi-tof) mass spectrometry (ms). to evaluate the utility of maldi-tof ms in tropical africa in collaboration with local teams, we installed an apparatus in the hôpital principal de dakar (senegal), performed routine identification of isolates, and confirmed or completed their identification in france. in the case of discordance or a la ... | 2015 | 26716681 |
| identification of a new marine bacterial strain sd8 and optimization of its culture conditions for producing alkaline protease. | while much attention has been given to marine microorganisms for production of enzymes, which in general are relatively more stable and active compared to those from plants and animals, studies on alkaline protease production from marine microorganisms have been very limited. in the present study, the alkaline protease producing marine bacterial strain sd8 isolated from sea muds in the geziwo qinhuangdao sea area of china was characterized and its optimal culture conditions were investigated. st ... | 2015 | 26716833 |
| triton hodge test: improved protocol for modified hodge test for enhanced detection of ndm and other carbapenemase producers. | accurate detection of carbapenemase-producing gram-negative bacilli is of utmost importance for the control of nosocomial spread and the initiation of appropriate antimicrobial therapy. the modified hodge test (mht), a carbapenem inactivation assay, has shown poor sensitivity in detecting the worldwide spread of new delhi metallo-β-lactamase (ndm). recent studies demonstrated that ndm is a lipoprotein anchored to the outer membrane in gram-negative bacteria, unlike all other known carbapenemases ... | 2016 | 26719442 |
| dissemination of carbapenemases producing gram negative bacteria in the middle east. | the emergence and spread of carbapenemase-producing bacteria, that hydolyze most β-lactams, including carbapenems, are a major concern of public health system worldwide, particularly in the middle east area. since the plasmids harboring resistance genes could be spread across other bacterial populations, detection of carbapenemase-producing organisms has become more problematic. these organisms produce different types of enzymes including the most prevalent types including kpc, vim, imp, ndm, an ... | 2015 | 26719779 |
| beta-ketoadipic acid and muconolactone production from a lignin-related aromatic compound through the protocatechuate 3,4-metabolic pathway. | in this work, the effects of pcaj (beta-ketoadipate:succinyl-coenzyme a transferase)- and pcad (beta-ketoadipate enol-lactone hydrolase)-inactivation on protocatechuic acid metabolism in pseudomonas putida kt2440 were evaluated. beta-ketoadipic acid was produced from protocatechuic acid by the inactivation of pcaj as expected; however, a portion of the produced beta-ketoadipic acid was converted to levulinic acid through a purification step consisting of extraction from the culture and recrystal ... | 2016 | 26723258 |
| a novel application of paracoccus pantotrophus for the decolorization of melanoidins from distillery effluent under static conditions. | melanoidin is the hazardous byproduct formed during the production of ethanol in distilleries. in the present study, a highly effective melanoidin decolorizing bacterial isolate, sag1, was isolated from the effluent enriched soil of a distillery. this strain, identified as paracoccus pantotrophus, was highly efficient to decolorize melanoidins up to 81.2 ± 2.43% in the presence of glucose and nh4no3. the effects of autoclaved as well as living cells and inoculums size on decolorization activity ... | 2016 | 26724506 |
| the industrial age of biocatalytic transamination. | during the last decade the use of ω-transaminases has been identified as a very powerful method for the preparation of optically pure amines from the corresponding ketones. their immense potential for the preparation of chiral amines, together with their ease of use in combination with existing biocatalytic methods, have made these biocatalysts a competitor to any chemical methodology for (asymmetric) amination. an increasing number of examples, especially from industry, shows that this biocatal ... | 2015 | 26726292 |
| plant root-microbe communication in shaping root microbiomes. | a growing body of research is highlighting the impacts root-associated microbial communities can have on plant health and development. these impacts can include changes in yield quantity and quality, timing of key developmental stages and tolerance of biotic and abiotic stresses. with such a range of effects it is clear that understanding the factors that contribute to a plant-beneficial root microbiome may prove advantageous. increasing demands for food by a growing human population increases t ... | 2016 | 26729479 |
| nicotine dehydrogenase complexed with 6-hydroxypseudooxynicotine oxidase involved in the hybrid nicotine-degrading pathway in agrobacterium tumefaciens s33. | nicotine, a major toxic alkaloid in tobacco wastes, is degraded by bacteria, mainly via pyridine and pyrrolidine pathways. previously, we discovered a new hybrid of the pyridine and pyrrolidine pathways in agrobacterium tumefaciens s33 and characterized its key enzyme 6-hydroxy-3-succinoylpyridine (hsp) hydroxylase. here, we purified the nicotine dehydrogenase initializing the nicotine degradation from the strain and found that it forms a complex with a novel 6-hydroxypseudooxynicotine oxidase. ... | 2016 | 26729714 |
| survival strategies of the plant-associated bacterium enterobacter sp. strain eg16 under cadmium stress. | plant-associated bacteria are of great interest because of their potential use in phytoremediation. however, their ability to survive and promote plant growth in metal-polluted soils remains unclear. in this study, a soilborne cd-resistant bacterium was isolated and identified as enterobacter sp. strain eg16. it tolerates high external cd concentrations (cd(2+) mic, >250 mg liter(-1)) and is able to produce siderophores and the plant hormone indole-3-acetic acid (iaa), both of which contribute t ... | 2016 | 26729719 |
| efficient and automated large-scale detection of structural relationships in proteins with a flexible aligner. | the total number of known three-dimensional protein structures is rapidly increasing. consequently, the need for fast structural search against complete databases without a significant loss of accuracy is increasingly demanding. recently, topsearch, an ultra-fast method for finding rigid structural relationships between a query structure and the complete protein data bank (pdb), at the multi-chain level, has been released. however, comparable accurate flexible structural aligners to perform effi ... | 2016 | 26732380 |
| metabolic engineering and comparative performance studies of synechocystis sp. pcc 6803 strains for effective utilization of xylose. | wood sugars such as xylose can be used as an inexpensive carbon source for biotechnological applications. the model cyanobacterium synechocystis sp. pcc 6803 lacks the ability to catabolize wood sugars as an energy source. here, we generated four synechocystis strains that heterologously expressed xylab enzymes, which mediate xylose catabolism, either in combination with or without one of three xylose transporters, namely xyle, galp, or glf. except for glf, which is derived from the bacterium zy ... | 2015 | 26732758 |
| year-long metagenomic study of river microbiomes across land use and water quality. | select bacteria, such as escherichia coli or coliforms, have been widely used as sentinels of low water quality; however, there are concerns regarding their predictive accuracy for the protection of human and environmental health. to develop improved monitoring systems, a greater understanding of bacterial community structure, function, and variability across time is required in the context of different pollution types, such as agricultural and urban contamination. here, we present a year-long s ... | 2015 | 26733955 |
| endophytic cultivable bacteria of the metal bioaccumulator spartina maritima improve plant growth but not metal uptake in polluted marshes soils. | endophytic bacterial population was isolated from spartina maritima tissues, a heavy metal bioaccumulator cordgrass growing in the estuaries of tinto, odiel, and piedras river (south west spain), one of the most polluted areas in the world. strains were identified and ability to tolerate salt and heavy metals along with plant growth promoting and enzymatic properties were analyzed. a high proportion of these bacteria were resistant toward one or several heavy metals and metalloids including as, ... | 2015 | 26733985 |
| systems biology of microbial exopolysaccharides production. | exopolysaccharides (epss) produced by diverse group of microbial systems are rapidly emerging as new and industrially important biomaterials. due to their unique and complex chemical structures and many interesting physicochemical and rheological properties with novel functionality, the microbial epss find wide range of commercial applications in various fields of the economy such as food, feed, packaging, chemical, textile, cosmetics and pharmaceutical industry, agriculture, and medicine. epss ... | 2015 | 26734603 |
| uptake and trans-membrane transport of petroleum hydrocarbons by microorganisms. | petroleum-based products are a primary energy source in the industry and daily life. during the exploration, processing, transport and storage of petroleum and petroleum products, water or soil pollution occurs regularly. biodegradation of the hydrocarbon pollutants by indigenous microorganisms is one of the primary mechanisms of removal of petroleum compounds from the environment. however, the physical contact between microorganisms and hydrophobic hydrocarbons limits the biodegradation rate. t ... | 2014 | 26740752 |
| influence of ni(2+) on urease activity produced by biofilms of arthrobacter oxydans 1388. | new tio2-based hybrid materials composed of an organic polymer, cellulose acetate butyrate and copolymer of acrylonitrile acrylamide (an + aa) were prepared. the effectiveness of immobilization of microbial strain arthrobacter oxydans 1388 on the newly synthesized hybrid membranes was investigated by biochemical methods. the obtained results revealed that the matrix more suitable for biofilm formation was composed of organic polymers without a metal component in the membrane composition. the inf ... | 2014 | 26740756 |
| insights into the stereospecificity of the d-specific dehalogenase from rhizobium sp. rc1 toward d- and l-2-chloropropionate. | halogenated compounds are recalcitrant environmental pollutants prevalent in agricultural fields, waste waters and industrial by-products, but they can be degraded by dehalogenase-containing microbes. notably, 2-haloalkanoic acid dehalogenases are employed to resolve optically active chloropropionates, as exemplified by the d-specific dehalogenase from rhizobium sp. rci (dehd), which acts on d-2-chloropropionate but not on its l-enantiomer. the catalytic residues of this dehalogenase responsible ... | 2014 | 26740767 |
| transport, retention, and long-term release behavior of zno nanoparticle aggregates in saturated quartz sand: role of solution ph and biofilm coating. | the transport, retention, and long-term release of zinc oxide nanoparticle aggregates (denoted below as zno-nps) were investigated in saturated, bare and biofilm (pseudomonas putida) coated sand packed columns. almost complete retention of zno-nps occurred in bare and biofilm coated sand when the influent solution ph was 9 and the ionic strength (is) was 0.1 or 10 mm nacl, and the retention profiles were always hyper-exponential. increasing the solution is and biofilm coating produced enhanced r ... | 2016 | 26741396 |
| pseudomonas putida stimulates primordia on agaricus bitorquis. | casing layer is one step of agaricus bisporus cultivation where there is a competitive environment with a high number of microorganisms and diversity interacting with mycelia. it is suggested that a minimal community of these microorganisms would be necessary to stimulate fructification. however, a. bisporus is not able to produce primordia in sterile casing layers or petri dishes. thus, the objective of this study was to characterize bacterial microbiota of casing layers from a. bisporus cultiv ... | 2016 | 26742772 |
| effects of carbazole-degradative plasmid pcar1 on biofilm morphology in pseudomonas putida kt2440. | bacteria typically form biofilms under natural conditions. to elucidate the effect of the carriage of carbazole-degradative plasmid pcar1 on biofilm formation by host bacteria, we compared the biofilm morphology, using confocal laser scanning microscopy, of three pcar1-free and pcar1-carrying pseudomonas hosts: p. putida kt2440, p. aeruginosa pao1 and p. fluorescens pf0-1. although pcar1 did not significantly affect biofilm formation by pao1 or pf0-1, pcar1-carrying kt2440 became filamentous and ... | 2016 | 26743211 |
| diversity and interactions of microbial functional genes under differing environmental conditions: insights from a membrane bioreactor and an oxidation ditch. | the effect of environmental conditions on the diversity and interactions of microbial communities has caused tremendous interest in microbial ecology. here, we found that with identical influents but differing operational parameters (mainly mixed liquor suspended solid (mlss) concentrations, solid retention time (srt) and dissolved oxygen (do) concentrations), two full-scale municipal wastewater treatment systems applying oxidation ditch (od) and membrane bioreactor (mbr) processes harbored a ma ... | 2016 | 26743465 |
| pseudomonas putida attunes morphophysiological, biochemical and molecular responses in cicer arietinum l. during drought stress and recovery. | drought is one of the most important abiotic stresses that adversely affect plant growth and yield potential. however, some drought resistant rhizosphere competent bacteria are known to improve plant health and promote growth during abiotic stresses. present study showed the role of pseudomonas putida mtcc5279 (ra) in ameliorating drought stress on cv. bg-362 (desi) and cv. bg-1003 (kabuli) chickpea cultivars under in vitro and green house conditions. polyethylene glycol-induced drought stress s ... | 2016 | 26744996 |
| diffusion of bacterial cells in porous media. | the chemotaxis signal transduction network regulates the biased random walk of many bacteria in favorable directions and away from harmful ones through modulating the frequency of directional reorientations. in mutants of diverse bacteria lacking the chemotaxis response, migration in classic motility agar, which constitutes a fluid-filled porous medium, is compromised; straight-swimming cells unable to tumble become trapped within the agar matrix. spontaneous mutations that restore spreading hav ... | 2016 | 26745427 |
| a novel enterocin t1 with anti-pseudomonas activity produced by enterococcus faecium t1 from chinese tibet cheese. | an enterocin-producing enterococcus faecium t1 was isolated from chinese tibet cheese. the enterocin was purified by sp-sepharose and reversed phase hplc. it was identified as unique from other reported bacteriocins based on molecular weight (4629 da) and amino acid compositions; therefore it was subsequently named enterocin t1. enterocin t1 was stable at 80-100 °c and over a wide ph range, ph 3.0-10.0. protease sensitivity was observed to trypsin, pepsin, papain, proteinase k, and pronase e. im ... | 2016 | 26745981 |