| toxicity of graphene oxide on growth and metabolism of pseudomonas putida. | the increasing consumption of graphene derivatives leads to greater presence of these materials in wastewater treatment plants and ecological systems. the toxicity effect of graphene oxide (go) on the microbial functions involved in the biological wastewater treatment process is studied, using pseudomonas putida and salicylic acid (sa) as bacterial and pollutant models. a multiparametric flow cytometry (fc) method has been developed to measure the metabolic activity and viability of p. putida in ... | 2016 | 26937871 |
| metabolomics reveals the physiological response of pseudomonas putida kt2440 (uwc1) after pharmaceutical exposure. | human pharmaceuticals have been detected in wastewater treatment plants, rivers, and estuaries throughout europe and the united states. it is widely acknowledged that there is insufficient information available to determine whether prolonged exposure to low levels of these substances is having an impact on the microbial ecology in such environments. in this study we attempt to measure the effects of exposing cultures of pseudomonas putida kt2440 (uwc1) to six pharmaceuticals by looking at differ ... | 2016 | 26932201 |
| release of outer membrane vesicles in pseudomonas putida as a response to stress caused by cationic surfactants. | pseudomonas putida a (atcc 12633), a degrader of cationic surfactants, releases outer membrane vesicles (omvs) when grown with tetradecyltrimethylammonium bromide (ttab) as the sole carbon, nitrogen and energy source. the omvs exhibit a bilayer structure and were found to be composed of lipopolysaccharides, proteins and phospholipids (pls) such as cardiolipin, phosphatidylcholine, phosphatidic acid and phosphatidylglycerol (pg). the omvs showed a marked increase in the pg content, approximately ... | 2016 | 26925774 |
| the revisited genome of pseudomonas putida kt2440 enlightens its value as a robust metabolic chassis. | by the time the complete genome sequence of the soil bacterium pseudomonas putida kt2440 was published in 2002 (nelson et al., ) this bacterium was considered a potential agent for environmental bioremediation of industrial waste and a good colonizer of the rhizosphere. however, neither the annotation tools available at that time nor the scarcely available omics data-let alone metabolic modeling and other nowadays common systems biology approaches-allowed them to anticipate the astonishing capac ... | 2016 | 26913973 |
| characterization of rhamnolipids by liquid chromatography/mass spectrometry after solid-phase extraction. | rhamnolipids are surface-active agents with a broad application potential that are produced in complex mixtures by bacteria of the genus pseudomonas. analysis from fermentation broth is often characterized by laborious sample preparation and requires hyphenated analytical techniques like liquid chromatography coupled to mass spectrometry (lc-ms) to obtain detailed information about sample composition. in this study, an analytical procedure based on chromatographic method development and characte ... | 2016 | 26879646 |
| structural and kinetic characterization of the 4-carboxy-2-hydroxymuconate hydratase from the gallate and protocatechuate 4,5-cleavage pathways of pseudomonas putida kt2440. | the bacterial catabolism of lignin and its breakdown products is of interest for applications in industrial processing of ligno-biomass. the gallate degradation pathway ofpseudomonas putidakt2440 requires a 4-carboxy-2-hydroxymuconate (chm) hydratase (galb), which has a 12% sequence identity to a previously identified chm hydratase (ligj) fromsphingomonassp. syk-6. the structure of galb was determined and found to be a member of the pig-ln-acetylglucosamine deacetylase family; galb is structural ... | 2016 | 26867578 |
| high resolution structures of periplasmic glucose-binding protein of pseudomonas putida csv86 reveal structural basis of its substrate specificity. | periplasmic substrate-binding proteins (sbps) bind to the specific ligand with high affinity and mediate their transport into the cytoplasm via the cognate inner membrane atp-binding cassette proteins. because of low sequence identities, understanding the structural basis of substrate recognition by sbps has remained very challenging. there are several structures available for the ligand-bound sugar sbps, but very few unliganded structures are reported. no structural data are available for sugar ... | 2016 | 26861882 |
| metabolic engineering of pseudomonas putida kt2440 for complete mineralization of methyl parathion and γ-hexachlorocyclohexane. | agricultural soils are often cocontaminated with multiple pesticides. unfortunately, microorganisms isolated from natural environments do not possess the ability to simultaneously degrade different classes of pesticides. currently, we can use the approaches of synthetic biology to create a strain endowed with various catabolic pathways that do not exist in a natural microorganism. here, we describe the metabolic engineering of a biosafety pseudomonas putida strain kt2440 for complete mineralizat ... | 2016 | 26854500 |
| biodegradation of chlorpyrifos by bacterial genus pseudomonas. | chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. it is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. contamination of chlorpyrifos has been found about 24 km from the site of its application. there are many physico-chemical and biological approa ... | 2016 | 26837064 |
| the toxin grat inhibits ribosome biogenesis. | most bacteria encode numerous chromosomal toxin-antitoxin (ta) systems that are proposed to contribute to stress tolerance, as they are able to shift the cells to a dormant state. toxins act on a variety of targets with the majority attacking the translational apparatus. intriguingly, the toxicity mechanisms of even closely related toxins may differ essentially. here, we report on a new type of ta toxin that inhibits ribosome biogenesis. grat of the grata system has previously been described in ... | 2016 | 26833678 |
| a pseudomonas putida double mutant deficient in butanol assimilation: a promising step for engineering a biological biofuel production platform. | biological production in heterologous hosts is of interest for the production of the c4 alcohol (butanol) and other chemicals. however, some hurdles need to be overcome in order to achieve an economically viable process; these include avoiding the consumption of butanol and maintaining tolerance to this solvent during production. pseudomonas putida is a potential host for solvent production; in order to further adapt p. putida to this role, we generated mini-tn5 mutant libraries in strain bird-1 ... | 2016 | 26818251 |
| mechanistic understanding of reduced agnp phytotoxicity induced by extracellular polymeric substances. | a knowledge gap concerning the potential effects of extracellular polymeric substances (eps), a common organic material but highly variable in their composition of microbial origin, on the fate and phytotoxicity of silver nanoparticles (agnp) still remains. a 48-h root elongation toxicity test showed that agnp toxicity to wheat triticum aestivum l. was dramatically alleviated by eps isolated from pseudomonas putida, as revealed by 7-59% increase in relative root elongation (rre), 8-99% increase ... | 2016 | 26808239 |
| comparisons of the transferability of plasmids pcar1, pb10, r388, and nah7 among pseudomonas putida at different cell densities. | the transferability of plasmids pcar1, pb10, r388, and nah7 was compared using the same donor-recipient system at different cell density combinations in liquid or on a solid surface. pcar1 was efficiently transferred in liquid, whereas the other plasmids were preferentially transferred on a solid surface. difference of liquid or solid affected the transfer frequency especially at lower cell densities. | 2016 | 26806196 |
| engineering synthetic bacterial consortia for enhanced desulfurization and revalorization of oil sulfur compounds. | the 4s pathway is the most studied bioprocess for the removal of the recalcitrant sulfur of aromatic heterocycles present in fuels. it consists of three sequential functional units, encoded by the dszabcd genes, through which the model compound dibenzothiophene (dbt) is transformed into the sulfur-free 2-hydroxybiphenyl (2hbp) molecule. in this work, a set of synthetic dsz cassettes were implanted in pseudomonas putida kt2440, a model bacterial "chassis" for metabolic engineering studies. the co ... | 2016 | 26802977 |
| pseudomonas putida kt2440 markerless gene deletion using a combination of λ red recombineering and cre/loxp site-specific recombination. | pseudomonas putida kt2440 is a saprophytic, environmental microorganism that plays important roles in the biodegradation of environmental toxic compounds and production of polymers, chemicals and secondary metabolites. gene deletion of kt2440 usually involves cloning of the flanking homologous fragments of the gene of interest into a suicide vector followed by transferring into kt2440 via triparental conjugation. selection and counterselection steps are then employed to generate gene deletion mu ... | 2016 | 26802072 |
| bioaccumulation of nickel by e. sativa and role of plant growth promoting rhizobacteria (pgprs) under nickel stress. | phytoremediation potential of plants can be enhanced in association with microbes. further, many plant growth-promoting rhizobacteria can improve growth under stress. the present study was conducted to investigate the effect of pseudomonas putida (p. putida) on nickel (ni) uptake and on growth of eruca sativa (e. sativa). three different levels of ni (low; 150 ug/g, medium; 250 ug/g and high; 500 ug/g) were applied to the soil containing e. sativa seedlings, with or without p. putida. ni-toxicit ... | 2016 | 26773835 |
| occurrence and ecological risk assessment of fluoroquinolone antibiotics in hospital waste of lahore, pakistan. | in the present study, wastewater and sludge samples of two major hospitals of lahore, pakistan were analyzed by developing an hplc-uv method for the possible occurrence of five frequently used fluoroquinolone antibiotics i.e. ofloxacin, ciprofloxacin, sparfloxacin, moxifloxacin and gemifloxacin. the highest detected concentration was for moxifloxacin in both wastewater (224 μg/l) and sludge samples (219 μg/kg. the highest concentration of ofloxacin, ciprofloxacin, sparfloxacin and gemifloxacin w ... | 2016 | 26773357 |
| toxicity of titanium dioxide nanoparticles on pseudomonas putida. | the increasing use of engineered nanoparticles (nps) in industrial and household applications will very likely lead to the release of such materials into the environment. as wastewater treatment plants (wwtps) are usually the last barrier before the water is discharged into the environment, it is important to understand the effects of these materials in the biotreatment processes, since the results in the literature are usually contradictory. we proposed the use of flow cytometry (fc) technology ... | 2016 | 26771160 |
| influence of oxygen transfer on pseudomonas putida effects on growth rate and biodesulfurization capacity. | the growth rate and desulfurization capacity accumulated by the cells during the growth of pseudomonas putida kth2 under different oxygen transfer conditions in a stirred and sparged tank bioreactor have been studied. hydrodynamic conditions were changed using different agitation conditions. during the culture, several magnitudes associated to growth, such as the specific growth rate, the dissolved oxygen concentration and the carbon source consumption have been measured. experimental results in ... | 2016 | 26762940 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| structure characterization of phospholipids and lipid a of pseudomonas putida kt2442. | pseudomonas putida kt2442 is an important bacterium for producing various types of polyhydroxyalkanoate polymers. phospholipids and lipid a in membranes of p. putida play important roles in stress responses, but detailed structural information of these lipids is not known. in this study, phospholipids and lipid a were isolated from p. putida kt2442, and their structures were analyzed using thin layer chromatography, high performance liquid chromatography, and electrospray ionization/mass spectro ... | 2015 | 26579930 |
| influence of the crc regulator on the hierarchical use of carbon sources from a complete medium in pseudomonas. | the crc protein, together with the hfq protein, participates in catabolite repression in pseudomonads, helping to coordinate metabolism. little is known about how crc affects the hierarchy of metabolite assimilation from complex mixtures. using proton nuclear magnetic resonance (nmr) spectroscopy, we carried out comprehensive metabolite profiling of culture supernatants (metabolic footprinting) over the course of growth of both pseudomonas putida and p. aeruginosa, and compared the wild-type str ... | 2016 | 26568055 |
| genetically engineered pseudomonas putida x3 strain and its potential ability to bioremediate soil microcosms contaminated with methyl parathion and cadmium. | a multifunctional pseudomonas putida x3 strain was successfully engineered by introducing methyl parathion (mp)-degrading gene and enhanced green fluorescent protein (egfp) gene in p. putida x4 (cctcc: 209319). in liquid cultures, the engineered x3 strain utilized mp as sole carbon source for growth and degraded 100 mg l(-1) of mp within 24 h; however, this strain did not further metabolize p-nitrophenol (pnp), an intermediate metabolite of mp. no discrepancy in minimum inhibitory concentrations ... | 2016 | 26521245 |
| environment-induced conformational and functional changes of l-2-haloacid dehalogenase. | 2-haloacid dehalogenases have been highly studied due to their potential applications in chemical industries and bioremediation. although biochemical and structural characterizations of the enzyme have been detailed, no information was available regarding environmental effects on the structure-function relationship. here, circular dichroism spectroscopy (cd) was used to investigate the correlation between changes on the conformation and the function of l-2-haloacid dehalogenase (hadl aj1) from t ... | 2016 | 26508534 |
| biosynthetic origin of the antibiotic pseudopyronines a and b in pseudomonas putida bw11m1. | within the framework of our effort to discover new antibiotics from pseudomonads, pseudopyronines a and b were isolated from the plant-derived pseudomonas putida bw11m1. pseudopyronines are 3,6-dialkyl-4-hydroxy-2-pyrones and displayed high in vitro activities against several human pathogens, and in our hands also towards the plant pathogen pseudomonas savastanoi. here, the biosynthesis of pseudopyronine b was studied by a combination of feeding experiments with isotopically labeled precursors, ... | 2015 | 26507104 |
| a newly isolated pseudomonas putida s-1 strain for batch-mode-propanethiol degradation and continuous treatment of propanethiol-containing waste gas. | pseudomonas putida s-1 was isolated from activated sludge. this novel strain was capable of degrading malodorous 1-propanethiol (pt). pt degradation commenced with no lag phase by cells pre-grown in nutrition-rich media, such as luria-bertani (lb), and pt-contained mineral medium at specific growth rates of 0.10-0.19 h(-1); this phenomenon indicated the operability of a large-scale cell culture. a possible pt degradation pathway was proposed on the basis of the detected metabolites, including di ... | 2016 | 26476310 |
| molecular level biodegradation of phenol and its derivatives through dmp operon of pseudomonas putida: a bio-molecular modeling and docking analysis. | participation of pseudomonas putida-derived methyl phenol (dmp) operon and dmpr protein in the biodegradation of phenol or other harmful, organic, toxic pollutants was investigated at a molecular level. documentation documents that p. putida has dmpr protein which positively regulates dmp operon in the presence of inducers; like phenols. from the operon, phenol hydroxylase encoded by dmpn gene, participates in degrading phenols after dmp operon is expressed. for the purpose, the 3-d models of th ... | 2015 | 26456616 |
| binary combination of epsilon-poly-l-lysine and isoeugenol affect progression of spoilage microbiota in fresh turkey meat, and delay onset of spoilage in pseudomonas putida challenged meat. | proliferation of microbial population on fresh poultry meat over time elicits spoilage when reaching unacceptable levels, during which process slime production, microorganism colony formation, negative organoleptic impact and meat structure change are observed. spoilage organisms in raw meat, especially gram-negative bacteria can be difficult to combat due to their cell wall composition. in this study, the natural antimicrobial agents ε-poly-l-lysine (ε-pl) and isoeugenol were tested individuall ... | 2015 | 26433458 |
| flavin mononucleotide (fmn)-based fluorescent protein (fbfp) as reporter for promoter screening in clostridium cellulolyticum. | conventional methods for screening promoters in anaerobic bacteria are generally based on detection of enzymatic reactions and thus usually complicated or strain specific. therefore a more efficient and universal method will be valuable. here, using cellulolytic bacteria clostridium cellulolyticum h10 as a model, we employed an oxygen-independent flavin-based fluorescent protein (fbfp) derived from pseudomonas putida as a quantitative reporter for the screening of promoter via monitoring fluores ... | 2015 | 26427827 |
| h2-driven biotransformation of n-octane to 1-octanol by a recombinant pseudomonas putida strain co-synthesizing an o2-tolerant hydrogenase and a p450 monooxygenase. | an in vivo biotransformation system is presented that affords the hydroxylation of n-octane to 1-octanol on the basis of nadh-dependent cyp153a monooxygenase and nad(+)-reducing hydrogenase heterologously synthesized in a bacterial host. the hydrogenase sustains h2-driven nadh cofactor regeneration even in the presence of o2, the co-substrate of monooxygenase. | 2015 | 26394141 |
| high-resolution analysis of the m-xylene/toluene biodegradation subtranscriptome of pseudomonas putida mt-2. | pseudomonas putida mt-2 metabolizes m-xylene and other aromatic compounds through the enzymes encoded by the xyl operons of the tol plasmid pww0 along with other chromosomally encoded activities. tiling arrays of densely overlapping oligonucleotides were designed to cover every gene involved in this process, allowing dissection of operon structures and exposing the interplay of plasmid and chromosomal functions. all xyl sequences were transcribed in response to aromatic substrates and the 3'-ter ... | 2016 | 26373670 |
| the rna chaperone hfq enables the environmental stress tolerance super-phenotype of pseudomonas putida. | the natural physiological regime of the soil bacterium pseudomonas putida involves incessant exposure to endogenous metabolic conflicts and environmental physicochemical insults. yet, the role of assisted small rna-mrna pairing in the stress tolerance super-phenotype that is the trademark of this bacterium has not been accredited. we have thoroughly explored the physiological consequences -in particular those related to exogenous stress - of deleting the hfq gene of p. putida, which encodes the ... | 2016 | 26373442 |
| toxicity of synthetic herbicides containing 2,4-d and mcpa moieties towards pseudomonas putida mt-2 and its response at the level of membrane fatty acid composition. | one of the attempts to create more effective herbicidal compounds includes the use of ionic liquids. herbicidal ionic liquids have more effective biological activity, they are less volatile, more thermally stable, and exhibit superior efficiency in comparison to typically employed herbicides, allowing the reduction of the herbicide dose applied per hectare. however, studies on the environmental toxicity of this group of compounds are very rarely available. environmental toxicity is an important ... | 2016 | 26347932 |
| understanding of real alternative redox partner of streptomyces peucetius doxa: prediction and validation using in silico and in vitro analyses. | streptomyces peucetius atcc27952 contains the cytochrome p450 monoxygenase doxa that is responsible for the hydroxylation of daunorubicin into doxorubicin. although s. peucetius atcc27952 contains several potential redox partners, the most suitable endogenous electron-transport system is still unclear; therefore, we conducted a study of potential redox partners using accelrys discovery studio 3.5. recombinant doxa along with its redox partners from s. peucetius fdx1, fdr2, and fdx3, and the puti ... | 2015 | 26334717 |
| cellulose derived graphenic fibers for capacitive desalination of brackish water. | we describe a simple and inexpensive cellulose-derived and layer-by-layer stacked carbon fiber network electrode for capacitive deionization (cdi) of brackish water. the microstructure and chemical composition were characterized using spectroscopic and microscopic techniques; electrochemical/electrical performance was evaluated by cyclic voltammetry and 4-probe electrical conductivity and surface area by brunauer-emmett-teller analysis, respectively. the desalination performance was investigated ... | 2015 | 26305260 |
| environmental stress speeds up dna replication in pseudomonas putida in chemostat cultivations. | cellular response to different types of stress is the hallmark of the cell's strategy for survival. how organisms adjust their cell cycle dynamics to compensate for changes in environmental conditions is an important unanswered question in bacterial physiology. a cell using binary fission for reproduction passes through three stages during its cell cycle: a stage from cell birth to initiation of replication, a dna replication phase and a period of cell division. we present a detailed analysis of ... | 2016 | 26299279 |
| pseudomonas alkylphenolica sp. nov., a bacterial species able to form special aerial structures when grown on p-cresol. | pseudomonas sp. kl28t is an aerobic, rod-shaped bacterium that was isolated from the soil of changwon, south korea, based on its ability to grow in the presence of linear alkylphenols (c1-c5). despite several studies on strain kl28t, it could not be assigned to any known species in the genus pseudomonas. the name 'pseudomonas alkylphenolia' was proposed for kl28t, but the strain had not until now been characterized taxonomically and the name currently has no standing in the bacterial nomenclatur ... | 2015 | 26276124 |
| photosynthetic aeration in biological wastewater treatment using immobilized microalgae-bacteria symbiosis. | chlorella vulgaris encapsulated in alginate beads were added into a bioreactor treating synthetic wastewater using pseudomonas putida. a symbiotic co2/o2 gas exchange was established between the two microorganisms for photosynthetic aeration of wastewater. during batch operation, glucose removal efficiency in the bioreactor improved from 50% in 12 h without aeration to 100% in 6 h, when the bioreactor was aerated photosynthetically. during continuous operation, the bioreactor was operated at a l ... | 2015 | 26266755 |
| isolation of a diphenylamine-degrading bacterium and characterization of its metabolic capacities, bioremediation and bioaugmentation potential. | the antioxidant diphenylamine (dpa) is used in fruit-packaging plants for the control of the physiological disorder apple scald. its use results in the production of dpa-contaminated wastewater which should be treated before finally discharged. biological treatment systems using tailored-made microbial inocula with specific catabolic activities comprise an appealing and sustainable solution. this study aimed to isolate dpa-degrading bacteria, identify the metabolic pathway of dpa and evaluate th ... | 2015 | 26260839 |
| assessment of toxicity and biodegradability on activated sludge of priority and emerging pollutants. | several methods for evaluating the toxicity and biodegradability of hazardous pollutants (chlorinated compounds, chemical additives and pharmaceuticals) have been studied in this work. different bioassays using representative bacteria of marine and terrestrial ecosystems such as vibrio fischeri and pseudomonas putida have been used to assess the ecotoxicity. activated sludge was used to analyse the effect of those pollutants in a biological reactor of a sewage treatment plant (stp). the results ... | 2016 | 26243262 |
| the potential of using low cost naturally available biogenic substrates for biological removal of chlorophenol. | this study details the application of naturally available biogenic substrates (nabs) in microbial degradation of 2-chlorophenol (cp). jatropha deoiled cakes (jdc) and karanja deoiled cakes (kdc) are used as nabs. the potential of nabs is compared with standard biogenic substrate, glucose. the study was carried out with both acclimatized mixed culture and pure culture, pseudomonas putida. microbial activity of the culture was monitored by measuring reduction in chlorophenol concentration, cod, to ... | 2015 | 26238237 |
| a new strategy for smoking cessation: characterization of a bacterial enzyme for the degradation of nicotine. | smoking is the leading cause of preventable diseases; thus, effective smoking cessation aids are crucial for reducing the prevalence of cigarette smoking and smoking-related illnesses. in our current campaign we offer a nicotine-degrading enzyme from pseudomonas putida, nica2, a flavin-containing protein. to explore its potential, a kinetic evaluation of the enzyme was conducted, which included determination of k(m), k(cat), buffer/serum half-life, and thermostability. additionally, the cataboli ... | 2015 | 26237398 |
| interplay of the ptsn (eiia(ntr)) protein of pseudomonas putida with its target sensor kinase kdpd. | the nitrogen phosphotransferase system (pts(ntr) ) of pseudomonas putida is a multi-component regulatory device that participates in controlling a variety of physiological processes in a post-translational fashion. a general survey of genes regulated by ptsn exposed transcription of the kdpfabc operon is most conspicuously affected. measurements of kdpfp promoter activity in different pts mutants showed that ptsn is responsible for repression of kdpfabc transcription. this effect could be assign ... | 2015 | 26224366 |
| phenolic wastewater treatment through extractive recovery coupled with biodegradation in a two-phase partitioning membrane bioreactor. | a two-phase partitioning membrane bioreactor (tppmb) was designed and operated for treatment of high strength phenolic wastewater through extraction/stripping and concomitant biodegradation. tributyl phosphate dissolved in kerosene was used as the organic phase, sodium hydroxide as the stripping phase and pseudomonas putida for biodegradation. in a semi-dispersive approach, organic phase dispersed in the stripping solution was contacted with wastewater through semi-permeable membranes for remova ... | 2015 | 26210322 |
| modeling the interplay of pseudomonas putida eiia with the potassium transporter kdpfabc. | the nitrogen phosphotransferase system (pts(ntr)) of pseudomonas putida is a key regulatory device that participates in controlling many physiological processes in a posttranscriptional fashion. one of the target functions of the pts(ntr) is the regulation of potassium transport. this is mediated by the direct interaction of one of its components with the sensor kinase kdpd of the two-component system controlling transcription of the kdpfabc genes. from a detailed experimental analysis of the ac ... | 2015 | 26159078 |
| heterofunctional magnetic metal-chelate-epoxy supports for the purification and covalent immobilization of benzoylformate decarboxylase from pseudomonas putida and its carboligation reactivity. | in this study, the combined use of the selectivity of metal chelate affinity chromatography with the capacity of epoxy supports to immobilize poly-his-tagged recombinant benzoylformate decarboxylase from pseudomonas putida (bfd, e.c. 4.1.1.7) via covalent attachment is shown. this was achieved by designing tailor-made magnetic chelate-epoxy supports. in order to selectively adsorb and then covalently immobilize the poly-his-tagged bfd, the epoxy groups (300 µmol epoxy groups/g support) and a ver ... | 2015 | 26147067 |
| tn7-based device for calibrated heterologous gene expression in pseudomonas putida. | the soil bacterium pseudomonas putida is increasingly attracting considerable interest as a platform for advanced metabolic engineering through synthetic biology approaches. however, genomic context, gene copy number, and transcription/translation interplay often introduce considerable uncertainty to the design of reliable genetic constructs. in this work, we have established a standardized heterologous expression device in which the promoter strength is the only variable; the remaining paramete ... | 2015 | 26133359 |
| label-free quantification reveals major proteomic changes in pseudomonas putida f1 during the exponential growth phase. | the physiological adaptation to stationary growth by pseudomonas putida f1, a model organism for the degradation of aromatic compounds, was investigated by proteome-wide label-free quantification.the data unveiled that entrance to the stationary phase did not involve an abrupt switch within the p. putida f1 proteome, but rather an ongoing adaptation that started already during the mid-exponential growth phase. the proteomic adaptations involved a clear increase in amino acid degradation capabili ... | 2015 | 26122999 |
| evaluation of an eventual ecotoxicity induced by textile effluents using a battery of biotests. | textile industry is considered as one of the important factors of the economic growth in tunisia. however, this prominent role has certainly some drawbacks mainly represented by the huge amounts of textile wastewaters generated that become a real menace to nature. many previous studies showed the purifying potential of some activated sludge and bacteria (pseudomonas putida) to decolourize textile effluents. however, in many cases, decolourization of wastewaters is not necessary associated with d ... | 2015 | 26087930 |
| a quick rhizobacterial selection tests for the remediation of copper contaminated soils. | the main objective of the study is to develop and improve quick bacterial tests to select the best candidates for the bioaugmentation of metal-contaminated soil, coupled with phytoextraction. | 2015 | 26042640 |
| biocompatibility of low molecular weight polymers for two-phase partitioning bioreactors. | two phase partitioning bioreactors (tppbs) improve the efficiency of fermentative processes by limiting the exposure of microorganisms to toxic solutes by sequestering them into a non-aqueous phase (nap). a potential limitation of this technology, when using immiscible organic solvents as the nap, is the cytoxicity that these materials may exert on the microbes. an improved tppb configuration is one in which polymeric naps are used to replace organic solvents in order to take advantage of their ... | 2015 | 26032439 |
| [the role of mineral phosphorus compounds in naphthalene biodegradation by pseudomonas putida]. | the effect of phosphate concentration in the culture medium on the growth and naphthalene degradation by pseudomonas putida bs 3701 was studied. the limiting concentration of phosphate was 0.4 mm and 0.1 mm under cultivation in media with naphthalene and glucose, respectively the phosphate deficiency correlated with a decrease in the activities of naphthalene dioxygenase and salicylate hydroxylase and with salicylate accumulation in the culture medium. we suggest that this fact indicates the imp ... | 2015 | 26027355 |
| plant growth-promoting effects of native pseudomonas strains on mentha piperita (peppermint): an in vitro study. | plant growth-promoting rhizobacteria (pgpr) affect growth of host plants through various direct and indirect mechanisms. three native pgpr (pseudomonas putida) strains isolated from rhizospheric soil of a mentha piperita (peppermint) crop field near córdoba, argentina, were characterised and screened in vitro for plant growth-promoting characteristics, such as indole-3-acetic acid (iaa) production, phosphate solubilisation and siderophore production, effects of direct inoculation on plant growth ... | 2015 | 26012535 |
| dynamics of suspended and attached aerobic toluene degraders in small-scale flow-through sediment systems under growth and starvation conditions. | the microbially mediated reactions, that are responsible for field-scale natural attenuation of organic pollutants, are governed by the concurrent presence of a degrading microbial community, suitable energy and carbon sources, electron acceptors, as well as nutrients. the temporal lack of one of these essential components for microbial activity, arising from transient environmental conditions, might potentially impair in situ biodegradation. this study presents results of small scale flow-throu ... | 2015 | 26009808 |
| effects of impurities in biodiesel-derived glycerol on growth and expression of heavy metal ion homeostasis genes and gene products in pseudomonas putida ls46. | biodiesel production-derived waste glycerol (wg) was previously investigated as potential carbon source for medium chain length polyhydroxyalkanoate (mcl-pha) production by pseudomonas putida ls46. in this study, we evaluated the effect of impurities in the wg on p. putida ls46 physiology during exponential growth and corresponding changes in transcription and protein expression profiles compared with cells grown on pure, reagent grade glycerol. high concentration of metal ions, such as na(+), a ... | 2015 | 26002633 |
| crude oil biodegradation aided by biosurfactants from pseudozyma sp. nii 08165 or its culture broth. | the aim of this work was to evaluate the biosurfactants produced by the yeast pseudozyma sp. nii 08165 for enhancing the degradation of crude oil by a model hydrocarbon degrading strain, pseudomonas putida mtcc 1194. pseudozyma biosurfactants were supplemented at various concentrations to the p. putida culture medium containing crude oil as sole carbon source. supplementation of the biosurfactants enhanced the degradation of crude oil by p. putida; the maximum degradation of hydrocarbons was obs ... | 2015 | 25985416 |
| oxidative stress in bacteria (pseudomonas putida) exposed to nanostructures of silicon carbide. | silicon carbide (sic) nanostructures produced by combustion synthesis can cause oxidative stress in the bacterium pseudomonas putida. the results of this study showed that sic nanostructures damaged the cell membrane, which can lead to oxidative stress in living cells and to the loss of cell viability. as a reference, micrometric sic was also used, which did not exhibit toxicity toward cells. oxidative stress was studied by analyzing the activity of peroxidases, and the expression of the glucose ... | 2015 | 25965002 |
| nhej enzymes ligd and ku participate in stationary-phase mutagenesis in pseudomonas putida. | under growth-restricting conditions bacterial populations can rapidly evolve by a process known as stationary-phase mutagenesis. bacterial nonhomologous end-joining (nhej) system which consists of the dna-end-binding enzyme ku and the multifunctional dna ligase ligd has been shown to be important for survival of bacteria especially during quiescent states, such as late stationary-phase populations or sporulation. in this study we provide genetic evidence that nhej enzymes participate in stationa ... | 2015 | 25942369 |
| mechanisms of solvent resistance mediated by interplay of cellular factors in pseudomonas putida. | a number of microorganisms have the ability to thrive in the presence of a range of toxic solvents. tolerance to these chemicals is a multifactorial process, meaning that bacterial cells use a set of physiological and gene expression changes to overcome the damage imparted by these chemicals. this review focuses mainly on issues related to tolerance to aromatic hydrocarbons and butanol in pseudomonas, although other microorganisms are also discussed. pseudomonas putida strains contain a circular ... | 2015 | 25934123 |
| engineering pseudomonas putida kt2440 for simultaneous degradation of organophosphates and pyrethroids and its application in bioremediation of soil. | agricultural soils are usually co-contaminated with organophosphate (op) and pyrethroid pesticides. to develop a stable and marker-free pseudomonas putida for co-expression of two pesticide-degrading enzymes, we constructed a suicide plasmid with expression cassettes containing a constitutive promoter j23119, an op-degrading gene (mpd), a pyrethroid-hydrolyzing carboxylesterase gene (pyth) that utilizes the upp gene as a counter-selectable marker for upp-deficient p. putida. by introduction of s ... | 2015 | 25917649 |
| thiamethoxam degradation by pseudomonas and bacillus strains isolated from agricultural soils. | twelve bacterial species were evaluated to know the degradation pattern of thiamethoxam in liquid medium. all the bacterial species could actively degrade phorate in a mineral salt medium containing phorate (50 μg ml(-1)) as sole carbon source. as these species have ability to degrade, we used these for the degradation of thiamethoxam--a neonicoitinoids. screening of 12 active phorate-metabolizing bacterial species resulted in selection of bacillus aeromonas strain imbl 4.1 and pseudomonas putid ... | 2015 | 25917187 |
| a new p. putida instrumental toxicity bioassay. | here, we present a new toxicity bioassay (co2-tox), able to detect toxic or inhibitory compounds in water samples, based on the quantification of pseudomonas putida kt2440 co2 production. the metabolically produced co2 was measured continuously and directly in the liquid assay media, with a potentiometric gas electrode. the optimization studies were performed using as a model toxicant 3,5-dcp (3,5-dichlorophenol); later, heavy metals (pb(2+), cu(2+), or zn(2+)) and a metalloid (as(5+)) were assa ... | 2015 | 25910719 |
| [influence of microcystin-lr on cell viability and surface characteristics of pseudomonas putida]. | in microcystin-lr (mc-lr) degradation system, the change in surface characteristics and cell viability of pseudomonas putida was studied. the purpose of this study was to reveal the influence of mc-lr on p. putida and elucidate the toxicity of mc-lr on microorganisms. the result demonstrated that mc-lr enhanced the cytoplasmic membrane permeability, as well as affected the ion metabolism and protein release of p. putida. the soluble sugar and na+, cl-release increased with the rising concentrati ... | 2015 | 25898672 |
| the c-di-gmp phosphodiesterase bifa regulates biofilm development in pseudomonas putida. | we previously showed the isolation of biofilmpersistent pseudomonas putida mutants that fail to undergo biofilm dispersal upon entry in stationary phase. two such mutants were found to bear insertions in pp0914, encoding a ggdef/eal domain protein with high similarity to pseudomon asaeruginosa bifa. here we show the phenotypic characterization of a δbifa mutant in p. putida kt2442.this mutant displayed increased biofilm and pellicle formation, cell aggregation in liquid medium and decreased star ... | 2015 | 25870874 |
| quantitative analysis of cellular proteome alterations of pseudomonas putida to naphthalene-induced stress. | to investigate whether genes other than the operons nahaaabacadbfced and nahgthinlomkj of pseudomonas putida are involved in the tolerance of the bacterium to naphthalene. | 2015 | 25868532 |
| detection and location of op-degrading activity: a model to integrate education and research. | the environmental sampling research module (esrm) is an investigative/discovery module that provides undergraduate research experiences for students as part of an interdisciplinary research-based biotechnology curriculum at the university of houston campus. as part of the esrm, students collect soil samples from various locations to test for the presence of organophosphorous (op) degrading bacteria. at the end of this research project students submit a research paper on their field and laborator ... | 2015 | 25863354 |
| the pww0 plasmid imposes a stochastic expression regime to the chromosomal ortho pathway for benzoate metabolism in pseudomonas putida. | environmental plasmids often expand the metabolic repertoire of bacteria that carry them, but they also interfere with the biochemical and genetic network of the host. the pww0 plasmid born by pseudomonas putida mt-2 encodes the tol pathway for degradation of toluene/m-xylene through production of intermediate compounds benzoate/3-methylbenzoate. these can be also recognized as substrates by the chromosomally encoded ben and cat gene products, thereby creating a manifest regulatory and biochemic ... | 2014 | 25848660 |
| analysis of the molecular response of pseudomonas putida kt2440 to the next-generation biofuel n-butanol. | to increase the efficiency of biocatalysts a thorough understanding of the molecular response of the biocatalyst to precursors, products and environmental conditions applied in bioconversions is essential. here we performed a comprehensive proteome and phospholipid analysis to characterize the molecular response of the potential biocatalyst pseudomonas putida kt2440 to the next-generation biofuel n-butanol. using complementary quantitative proteomics approaches we were able to identify and quant ... | 2015 | 25829261 |
| repeated batch and continuous degradation of chlorpyrifos by pseudomonas putida. | the present study was undertaken with the objective of studying repeated batch and continuous degradation of chlorpyrifos (o,o-diethyl o-3,5,6-trichloropyridin-2-yl phosphorothioate) using ca-alginate immobilized cells of pseudomonas putida isolated from an agricultural soil, and to study the genes and enzymes involved in degradation. the study was carried out to reduce the toxicity of chlorpyrifos by degrading it to less toxic metabolites. long-term stability of pesticide degradation was studie ... | 2015 | 25826103 |
| genome-wide investigation of the genes involved in nicotine metabolism in pseudomonas putida j5 by tn5 transposon mutagenesis. | pseudomonas putida j5 is an efficient nicotine-degrading bacterial strain isolated from the tobacco rhizosphere. we successfully performed a comprehensive whole-genome analysis of nicotine metabolism-associated genes by tn5 transposon mutagenesis in p. putida j5. a total of 18 mutants with unique insertions screened from 16,324 tn5-transformants failed to use nicotine as the sole carbon source. flanking sequences of the tn5 transposon were cloned with a shotgun method from all of the nicotine-gr ... | 2015 | 25808517 |
| an integrated view of redox and catalytic properties of b-type ppdyp from pseudomonas putida met94 and its distal variants. | ppdyp from pseudomonas putida met94 is an extremely versatile b-type dye-decolourising peroxidase (dyp) capable of efficient oxidation of a wide range of anthraquinonic and azo dyes, phenolic substrates, the non-phenolic veratryl alcohol and even manganese and ferrous ions. in reaction with h2o2 it forms a stable compound i at a rate of (1.4±0.3)×10(6)m(-1)s(-1), comparable to those of classical peroxidases and other dyps. we provide the first report of standard redox potential (e(0')) of the co ... | 2015 | 25797439 |
| continuous ozonation treatment of ofloxacin: transformation products, water matrix effect and aquatic toxicity. | the continuous ozonation of the antibiotic ofloxacin (ofx) has been performed using a synthetic water matrix and in a sewage treatment plant (stp) effluent. the aim was to study the effect of the water matrix on the ozonation with particular emphasis on the aquatic toxicity of treated water. ofx was completely removed in both water matrices, although the amount of ozone consumed for its depletion was strongly matrix-dependent. the extent of mineralization was limited and a number of intermediate ... | 2015 | 25796038 |
| 5-methyl phenazine-1-carboxylic acid: a novel bioactive metabolite by a rhizosphere soil bacterium that exhibits potent antimicrobial and anticancer activities. | a new rhizosphere soil bacterium that exhibits antimicrobial potential against human pathogens was isolated. on the basis of 16s ribosomal rna nucleotide sequence homology and subsequent phylogenetic tree analysis, the strain puw5 was identified as pseudomonas putida. a bioactive metabolite was extracted and purified using silica gel column chromatography and preparative hplc. characterization of metabolite was done by employing fourier transform infrared spectroscopy (ftir), nuclear magnetic re ... | 2015 | 25765238 |
| effect of silver nanoparticles on pseudomonas putida biofilms at different stages of maturity. | this study determined the effect of silver nanoparticles (agnps) on pseudomonas putida kt2440 biofilms at different stages of maturity. three biofilm stages (1-3, representing early to late stages of development) were identified from bacterial adenosine triphosphate (atp) activity under static (96-well plate) and dynamic conditions (center for disease control and prevention biofilm reactor). extracellular polymeric substance (eps) levels, measured using crystal violet and total carbohydrate assa ... | 2015 | 25756827 |
| complete genome sequence of solvent-tolerant pseudomonas putida s12 including megaplasmid ptts12. | pseudomonas putida s12 is a solvent-tolerant gamma-proteobacterium with an extensive track record for production of industrially relevant chemicals. here we report the annotated complete genome sequence of this organism, including the megaplasmid ptts12 which encodes many of the unique features of the s12 strain. | 2015 | 25746905 |
| systematic profiling of indole-3-acetic acid biosynthesis in bacteria using lc-ms/ms. | indole-3-acetic acid (iaa) is produced from tryptophan through five synthesis pathways. a comprehensive method for the quantification of iaa and biosynthesis-related intermediates in a culture medium was developed. sample preparation was simple with protein precipitation. the analytes were separated on a superficially porous c18 silica column and detected by electrospray ionization-tandem mass spectrometry in the positive ion multiple reaction monitoring mode. the limit of detection was 0.05 μm, ... | 2015 | 25746752 |
| impact of dissolved organic matter on bacterial tactic motility, attachment, and transport. | bacterial dispersal is a key driver of the ecology of microbial contaminant degradation in soils. this work investigated the role of dissolved organic matter (dom) in the motility, attachment, and transport of the soil bacterium pseudomonas putida g7 in saturated porous media. the study is based on the hypothesis that dom quality is critical to triggering tactic motility and, consequently, affects bacterial transport and dispersal. sunflower root exudates, humic acids (ha), and the synthetic ole ... | 2015 | 25734420 |
| engineering biological approaches for detection of toxic compounds: a new microbial biosensor based on the pseudomonas putida ttgr repressor. | environmental contamination by toxic organic compounds and antimicrobials is one of the causes for the recent surge of multidrug-resistant pathogenic bacteria. monitoring contamination is therefore the first step in containment of antimicrobial resistance and requires the development of simple, sensitive, and quantitative tools that detect a broad spectrum of toxic compounds. in this study, we have engineered a new microbial biosensor based on the ttgr-regulated promoter that controls expression ... | 2015 | 25731724 |
| the quest for a practical synthesis of morphine alkaloids and their derivatives by chemoenzymatic methods. | we became interested in approaches to morphine in the early 1990s following our immersion into the new program on the enzymatic dihydroxylation of aromatics. larry kwart, a former classmate of one of us at rice university, who worked with our group at virginia tech in the mid-1980s, introduced to us the use of blocked mutants of pseudomonas putida (pp39d) for the production of arene-cis-dihydrodiols. larry had gained expertise in microbiology from a postdoctoral stay with david gibson, who disco ... | 2015 | 25730681 |
| molecular dynamics investigation of the substrate binding mechanism in carboxylesterase. | a recombinant carboxylesterase, cloned from pseudomonas putida and designated as rppe, is capable of catalyzing the bioresolution of racemic 2-acetoxy-2-(2'-chlorophenyl)acetate (rac-aco-cpa) with excellent (s)-enantioselectivity. semirational design of the enzyme showed that the w187h variant could increase the activity by ∼100-fold compared to the wild type (wt) enzyme. in this study, we performed all-atom molecular dynamics (md) simulations of both apo-rppe and rppe in complex with (s)-aco-cp ... | 2015 | 25711934 |
| the crc/crcz-crcy global regulatory system helps the integration of gluconeogenic and glycolytic metabolism in pseudomonas putida. | in metabolically versatile bacteria, carbon catabolite repression (ccr) facilitates the preferential assimilation of the most efficient carbon sources, improving growth rates and fitness. in pseudomonas putida, the crc and hfq proteins and the crcz and crcy small rnas, which are believed to antagonize crc/hfq, are key players in ccr. unlike that seen in other bacterial species, succinate and glucose elicit weak ccr in this bacterium. in the present work, metabolic, transcriptomic and constraint- ... | 2015 | 25711694 |
| genes involved in nutrient competition by pseudomonas putida jbc17 to suppress green mold in postharvest satsuma mandarin. | understanding the mechanisms underlying biocontrol activity in biocontrol agents is indispensable to implement biological control. however, the understanding of specific mechanisms for nutrient competition in nutrient limited environments is still limited. this study was performed to control green mold of postharvest satsuma mandarin (mandarin) using pseudomonas putida jbc17 (jbc17), and identify the genes involved in nutrient competition. treatment with jbc17 on wounded mandarin fruits at a con ... | 2015 | 25707389 |
| hormetic effect of ionic liquid 1-ethyl-3-methylimidazolium acetate on bacteria. | the biological effect of ionic liquids (ils) is one of the highly debated topics as they are being contemplated for various industrial applications. 1-ethyl-3-methylimidazolium acetate ([emim][ac]) showed remarkable hormesis on anaerobic clostridium sp. and aerobic pseudomonas putida. bacterial growth was stimulated at up to 2.5 g l(-1) and inhibited at >2.5 g l(-1) of [emim][ac]. the growth of clostridium sp. and p. putida were higher by 0.4 and 4-fold respectively, in the presence of 0.5 g l(- ... | 2015 | 25703901 |
| engineering towards nitroreductase functionality in ene-reductase scaffolds. | nitroreductases (nrs) and ene-reductases (ers) both utilize flavin mononucleotide cofactors but catalyze distinct reactions. nrs reduce nitroaromatics, whereas ers reduce unsaturated c=c double bonds, and these functionalities are known to somewhat overlap. recent studies on the er xenobiotic reductase a (xena) from pseudomonas putida demonstrated the possibility of increasing nr activity with active site modifications. structural comparison between nrs and ers led us to hypothesize that active ... | 2015 | 25703443 |
| cometabolism of methyl tert-butyl ether by a new microbial consortium ers. | the release of methyl tert-butyl-ether (mtbe) into the environment has increased the worldwide concern about the pollution of mtbe. in this paper, a microbial consortium was isolated from the soil sample near an oil station, which can degrade mtbe directly with a low biomass yield and mtbe degrading efficiency. further research has indicated that this consortium can degrade mtbe efficiently when grown on n-octane as the cometabolic substrate. the results of 16s rdna based on phylogenetic analysi ... | 2015 | 25697553 |
| the two paralogue phon (phosphinothricin acetyl transferase) genes of pseudomonas putida encode functionally different proteins. | phosphinothricin (ppt) is a non-specific inhibitor of glutamine synthetase that has been employed as herbicide for selection of transgenic plants expressing cognate resistance genes. while the soil bacterium pseudomonas putida kt2440 has been generally considered ppt-sensitive, inspection of its genome sequence reveals the presence of two highly similar open reading frames (pp_1924 and pp_4846) encoding acetylases with a potential to cause tolerance to the herbicide. to explore this possibility, ... | 2015 | 25684119 |