| components from wheat roots modify the bioactivity of zno and cuo nanoparticles in a soil bacterium. | zno and cuo nanoparticles (nps) have widespread commercial uses and their impact on agricultural systems is unresolved. this study examined whether the metabolites washed from wheat (triticum aestivum l.) roots modulated the metabolic response to the nps of a biosensor generated in the root colonizer, pseudomonas putida kt2440. the root wash components boosted light output of the biosensor consistent with their catabolism. dose-dependent and rapid inhibition of cell metabolism occurred with both ... | 2014 | 24448483 |
| interaction among multiple microorganisms and effects of nitrogen and carbon supplementations on lignin degradation. | the mutual interactions among the consortium constructed by four indigenous bacteria and five inter-kingdom fusants and the effects of nitrogen and carbon supplementations on lignin degradation and laccase activity were investigated. analyzed by plackett-burman and central composite design, the microbial consortium were optimized, bacillus sp. (b) and pe-9 and pseudomonas putida (pp) and pe-9 had significant interactions on lignin degradation based on a 5% level of significance. the nitrogen and ... | 2014 | 24445191 |
| a stable synergistic microbial consortium for simultaneous azo dye removal and bioelectricity generation. | microbial species coexist in natural or engineered settings, where they encounter extensive competition and cooperation. interactions occurring through metabolite exchange or direct contact might be important in establishment of functional biodegradation consortium. understanding these interactions can facilitate manipulation of selected communities and exploitation of their capacity for specific industrial applications. here, a simple dual-species consortium (pseudomonas putida and shewanella o ... | 2014 | 24434696 |
| electrooxidation of industrial wastewater containing 1,4-dioxane in the presence of different salts. | the treatment of 1,4-dioxane solution by electrochemical oxidation on boron-doped diamond was studied using a central composite design and the response surface methodology to investigate the use of so4 (2-) and hco3 (-) as supporting electrolytes considering the applied electric current, initial chemical oxygen demand (cod) value, and treatment time. two industrial effluents containing bicarbonate alkalinity, one just carrying 1,4-dioxane (s1), and another one including 1,4-dioxane and 2-methyl- ... | 2014 | 24430500 |
| functional analyses of three acyl-coa synthetases involved in bile acid degradation in pseudomonas putida doc21. | pseudomonas putida doc21, a soil-dwelling proteobacterium, catabolizes a variety of steroids and bile acids. transposon mutagenesis and bioinformatics analyses identified four clusters of steroid degradation (std) genes encoding a single catabolic pathway. the latter includes three predicted acyl-coa synthetases encoded by stda1, stda2 and stda3 respectively. the δstda1 and δstda2 deletion mutants were unable to assimilate cholate or other bile acids but grew well on testosterone or 4-androstene ... | 2015 | 24428272 |
| effect of flexibility and positive charge of the c-terminal domain on the activator p14k function for nitrile hydratase in pseudomonas putida. | a self-subunit swapping chaperone is crucial for cobalt incorporation into nitrile hydratase. however, further information about its structural features is not available. the flexibility and positive charge of the c-terminal domain of the self-subunit swapping chaperone (p14k) of nitrile hydratase from pseudomonas putida nrrl-18668 play an important role in cobalt incorporation. c-terminal domain truncation, alternation of c-terminal domain flexibility through mutant p14k(g86i), and elimination ... | 2014 | 24417729 |
| pseudomonas putida response in membrane bioreactors under salicylic acid-induced stress conditions. | starvation and changing feeding conditions are frequently characteristics of wastewater treatment plants. they are typical causes of unsteady-state operation of biological systems and provoke cellular stress. the response of a membrane bioreactor functioning under feed-induced stress conditions is studied here. in order to simplify and considerably amplify the response to stress and to obtain a reference model, a pure culture of pseudomonas putida was selected instead of an activated sludge and ... | 2014 | 24413046 |
| differential gene expression profile in pseudomonas putida nbric19-treated wheat (triticum aestivum) plants subjected to biotic stress of parthenium hysterophorus. | the inoculation of pseudomonas putida nbric19 protected wheat plant from phytotoxic effect of parthenium hysterophorus (parthenium) and enhanced root length, shoot length, dry weight, spike length and chlorophyll content. with the aim to screen for genes differentially expressed in p. putida nbric19-inoculated wheat grown along with parthenium (wpt), the suppression subtractive hybridization (ssh) methodology was employed. the ssh analysis was performed with wpc (uninoculated wheat grown along w ... | 2014 | 24407601 |
| structural insights into the specific recognition of n-heterocycle biodenitrogenation-derived substrates by microbial amide hydrolases. | n-heterocyclic compounds from industrial wastes, including nicotine, are environmental pollutants or toxicants responsible for a variety of health problems. microbial biodegradation is an attractive strategy for the removal of n-heterocyclic pollutants, during which carbon-nitrogen bonds in n-heterocycles are converted to amide bonds and subsequently severed by amide hydrolases. previous studies have failed to clarify the molecular mechanism through which amide hydrolases selectively recognize d ... | 2014 | 24397579 |
| the prc and rsep proteases control bacterial cell-surface signalling activity. | extracytoplasmic function (ecf) sigma factors play a key role in the regulation of vital functions in the bacterial response to the environment. in gram-negative bacteria, activity of these sigma factors is often controlled by cell-surface signalling (css), a regulatory system that also involves an outer membrane receptor and a transmembrane anti-sigma factor. to get more insight into the molecular mechanism behind css regulation, we have focused on the unique iut system of pseudomonas putida. t ... | 2014 | 24373018 |
| molecular and in situ characterization of cadmium-resistant diversified extremophilic strains of pseudomonas for their bioremediation potential. | cadmium-resistant strains psychrotolerant pseudomonas putida sb32 and alkalophilic pseudomonas monteilli sb35 were originally isolated from the soil of semera mines, palamau, jharkhand, india. further, to unravel the mechanism involved in cadmium resistance, plasmid dna was isolated from the strains and subjected to amplification of the czc gene, which is responsible for the efflux of three metal cations, viz. co, zn and cd, from the cell. furthermore, the amplicon was cloned into pdrive cloning ... | 2014 | 28324433 |
| use of snares for the immobilization of poly-3-hydroxyalkanoate polymerase type ii of pseudomonas putida ca-3 in secretory vesicles of saccharomyces cerevisiae atcc 9763. | polyhydroxyalkanoate (pha) synthase, the key enzyme in polyester biosynthesis of bacteria, has been targeted to various organelles in yeasts and plants using respective signal peptides. here, we report that the sequences derived from snare domains efficiently target and integrate the pha synthase from pseudomonas putida ca-3 to the membrane of secretory vesicles in saccharomyces cerevisiae. the studies with the enhanced green fluorescent protein confirm the localization of synthase enzyme in the ... | 2014 | 24368219 |
| synthesis, characterization, cytotoxicity and antibacterial activity of an anthracenyl-linked bis(pyrazolyl)methane ligand and its zinc(ii) complexes. | three novel zn(ii) complexes (1-3) with 1,1'-(anthracen-9-ylmethylene)bis(1h-pyrazole) (l(2)) have been prepared and structurally characterized by x-ray crystallography. among them, 1 is a binuclear zn(ii) complex while 2 and 3 are mononuclear. the in vitro cytotoxic and antibacterial activities of these complexes were also evaluated. the three complexes exhibit cytotoxic specificity and significant antitumor activity. the mic50 value of complex 1 against pseudomonas putida reaching 0.011 μg/ml ... | 2014 | 24342667 |
| a second chromosomal copy of the cata gene endows pseudomonas putida mt-2 with an enzymatic safety valve for excess of catechol. | pseudomonas putida mt-2 harbours two different routes for catabolism of catechol, namely one meta pathway encoded by the xyl genes of the tol plasmid pww0 and one ortho pathway determined by the chromosomal ben and cat genes. p. putida mt-2 has a second chromosomal copy of the cata gene (named cata2) located downstream of the ben operon that encodes an additional catechol-1,2-dioxygenase. the metabolic and regulatory phenotypes of strains lacking one enzyme, the other and both of them in cells w ... | 2014 | 24341396 |
| the private life of environmental bacteria: pollutant biodegradation at the single cell level. | bacteria display considerable cell-to-cell heterogeneity in a number of genetic and physiological traits. stochastic differences in regulatory patterns (e.g. at the transcriptional level) propagate into the metabolic and physiological status of otherwise isogenic cells, which ultimately results in appearance of sub-populations within the community. as new technologies emerge and because novel single cell strategies are constantly being refined, our knowledge on microbial individuality is in burg ... | 2014 | 24341371 |
| [anti-diatom compounds from marine bacterium pseudomonas putida]. | in order to provide more natural antifouling compounds, marine bacterium pseudomonas putida isolated from the sponge haliclona sp. was explored to test its anti-diatom compounds. | 2013 | 24341274 |
| new insights in the formation of polyhydroxyalkanoate granules (carbonosomes) and novel functions of poly(3-hydroxybutyrate). | the metabolism of polyhydroxybutyrate (phb) and related polyhydroxyalkanoates (phas) has been investigated by many groups for about three decades, and good progress was obtained in understanding the mechanisms of biosynthesis and biodegradation of this class of storage molecules. however, the molecular events that happen at the onset of phb synthesis and the details of the initiation of phb/pha granule formation, as well as the complex composition of the proteinaceous surface layer of phb/pha gr ... | 2014 | 24329995 |
| construction and optimization of a pseudomonas putida whole-cell bioreporter for detection of bioavailable copper. | a pseudomonas putida whole-cell bioreporter for detecting bioavailable copper was constructed by inserting a cuer-regulated sensor element upstream of a promoterless green fluorescent protein (gfp) reporter gene. the constructed bioreporter cells expressed gfp only in response to cu and ag when cultivated in different metal salt solutions. m9 supplemented medium provided higher sensitivity compared with lb medium. the optimal test condition was cell suspension with an od600 of 0.4-0.5 incubated ... | 2014 | 24322773 |
| toxicity assessment of sic nanofibers and nanorods against bacteria. | in the present study, evidence of the antibacterial effects of silicon carbide (sic) nanofibers (nfsic) and nanorods (nrsic) obtained by combustion synthesis has been presented. it has been shown that the examined bacteria, pseudomonas putida, could bind to the surface of the investigated sic nanostructures. the results of respiration measurements, dehydrogenase activity measurements, and evaluation of viable bacteria after incubation with nfsic and nrsic demonstrated that the nanostructures of ... | 2014 | 24290890 |
| investigating pseudomonas putida-candida humicola interactions as affected by chelate fe(iii) in soil. | microcalorimetric technique was applied to assess the toxic effect of edta-chelated trivalent iron on pseudomonas putida (p. putida) (bacterium), candida humicola (c. humicola) (fungus) and their mixture in sterilized soil. microbial growth rate constant k, total heat evolution q t, metabolic enthalpy ∆h met, mass specific heat rate j q/s, microbial biomass c and inhibitory ratio i were calculated. results showed that microcalorimetric indexes decreased with the increasing fe(iii)-edta complex c ... | 2014 | 24270965 |
| isotope fractionation associated with the biodegradation of 2- and 4-nitrophenols via monooxygenation pathways. | monooxygenation is an important route of nitroaromatic compound (nac) biodegradation and it is widely found for cometabolic transformations of nacs and other aromatic pollutants. we investigated the c and n isotope fractionation of nitrophenol monooxygenation to complement the characterization of nac (bio)degradation pathways by compound-specific isotope analysis (csia). because of the large diversity of enzymes catalyzing monooxygenations, we studied the combined c and n isotope fractionation a ... | 2013 | 24266668 |
| transcriptomic fingerprinting of pseudomonas putida under alternative physiological regimes. | pseudomonas putida kt2440 is a metabolically versatile soil bacterium useful both as a model biodegradative organism and as a host of catalytic activities of biotechnological interest. in this report, we present the high-resolution transcriptome of p. putida cultured on different carbon sources as revealed by deep sequencing of the corresponding rna pools. examination of the data from growth on substrates that are processed through distinct pathways (glucose, fructose, succinate and glycerol) re ... | 2013 | 24249296 |
| the pseudomonas putida hska hybrid sensor kinase responds to redox signals and contributes to the adaptation of the electron transport chain composition in response to oxygen availability. | pseudomonas putida has a branched aerobic electron transport that includes five terminal oxidases, each of which has different properties. the relative expression of each oxidase is carefully regulated to assemble the most suitable electron transport chain for the prevailing conditions. the hska hybrid sensor kinase participates in this control, but the signals to which hska responds were unknown. here, the influence of hska on the mrna abundance of genes coding for all terminal oxidases and for ... | 2013 | 24249291 |
| enhanced cadmium resistance and accumulation in pseudomonas putida kt2440 expressing the phytochelatin synthase gene of schizosaccharomyces pombe. | phytochelatins (pcs) are cysteine-rich peptides with high binding affinity for toxic metals. expressing the pc synthase gene (pcs) in plant growth-promoting bacteria may enhance its metal resistance and accumulation, consequently increasing phytoremediation efficiency in heavy metal pollution. in this study, pcs from schizosaccharomyces pombe was cloned and expressed in pseudomonas putida kt2440, which was confirmed by real-time rt-pcr through an increase in sppcs mrna expression level when indu ... | 2014 | 24236847 |
| development and characterization of microbial biosensors for evaluating low biochemical oxygen demand in rivers. | five microorganisms were used to construct a biosensor for the evaluation of low biochemical oxygen demand (bod) in rivers. characterization and comparison of bod biosensors were performed using two standard solutions: glucose and glutamic acid (gga) and artificial wastewater (aww). pseudomonas putida sg10 demonstrated the best response when using aww. trichosporon cutaneum ifo10466, however, had an extremely poor response. when evaluating the biosensor response to each component of aww, all of ... | 2013 | 24209354 |
| partial bioaugmentation to remove 3-chloroaniline slows bacterial species turnover rate in bioreactors. | bioaugmentation is a potentially powerful tool to direct community structure and metabolic capacities in bioreactors. yet the outcome of bioaugmentation studies is usually unpredictable and effects on microbial community dynamics are poorly understood. we asked the question whether bioaugmentation could prevent a diversity shift induced by a model toxin, 3-chloroaniline (3-ca), regardless of whether 3-ca was degraded. four replicate membrane bioreactors (mbrs) operating in parallel were amended ... | 2013 | 24200008 |
| medium chain length polyhydroxyalkanoate (mcl-pha) production from volatile fatty acids derived from the anaerobic digestion of grass. | a two step biological process for the conversion of grass biomass to the biodegradable polymer medium chain length polyhydroxyalkanoate (mcl-pha) was achieved through the use of anaerobic and aerobic microbial processes. anaerobic digestion (mixed culture) of ensiled grass was achieved with a recirculated leach bed bioreactor resulting in the production of a leachate, containing 15.3 g/l of volatile fatty acids (vfas) ranging from acetic to valeric acid with butyric acid predominating (12.8 g/l) ... | 2014 | 24162086 |
| improved production of medium-chain-length polyhydroxyalkanoates in glucose-based fed-batch cultivations of metabolically engineered pseudomonas putida strains. | one of the major challenges in metabolic engineering for enhanced synthesis of value-added chemicals is to design and develop new strains that can be translated into well-controlled fermentation processes using bioreactors. the aim of this study was to assess the influence of various fed-batch strategies in the performance of metabolically engineered pseudomonas putida strains, δgcd and δgcd-pgl, for improving production of medium-chain-length polyhydroxyalkanoates (mcl-phas) using glucose as th ... | 2014 | 24150495 |
| the metabolic cost of flagellar motion in pseudomonas putida kt2440. | although the flagellar machinery of environmental bacteria endows cells with a phenomenal survival device, it also consumes much of the metabolic currency necessary for fuelling such a vigorous nano-motor. the physiological cost of flagella-related functions of the soil bacterium pseudomonas putida kt2440 was examined and quantified through the deletion of a ≈ 70 kb dna segment of the genome (≈ 1.1%), which includes relevant structural and regulatory genes in this micro-organism. the resulting s ... | 2014 | 24148021 |
| toxicity of perfluorooctanoic acid to pseudomonas putida in the aquatic environment. | perfluorinated compounds are potential persistent organic pollutants which attracted much concerns in recent years. thus relevant toxicity data of perfluorooctanoic acid (pfoa) are vitally important for identification of possible risk in the aquatic environment. in the present study, the acute toxic effect of pfoa in the absence and presence of either chromium (iii) or tetra butyl ammonium (tba) towards pseudomonas putida in the aquatic environment was investigated by microcalorimetry. the therm ... | 2013 | 24140521 |
| a new bioseed for determination of wastewater biodegradability: analysis of the experimental procedure. | a new bioassay proposed in the patent p201300029 was applied to a pre-treated wastewater containing a mixture of commercial pesticides to simulate a recalcitrant industrial wastewater in order to determine its biodegradability. the test uses a mixture of standardized inoculum of the lyophilized bacteria pseudomonas putida with the proper proportion of salts and minerals. the results highlight that biodegradation efficiency can be calculated using a gross parameter (chemical oxygen demand (cod)) ... | 2014 | 24136578 |
| genetic engineering of pseudomonas putida kt2440 for rapid and high-yield production of vanillin from ferulic acid. | vanillin is one of the most important flavoring agents used today. that is why many efforts have been made on biotechnological production from natural abundant substrates. in this work, the nonpathogenic pseudomonas putida strain kt2440 was genetically optimized to convert ferulic acid to vanillin. deletion of the vanillin dehydrogenase gene (vdh) was not sufficient to prevent vanillin degradation. additional inactivation of a molybdate transporter, identified by transposon mutagenesis, led to a ... | 2014 | 24136472 |
| involvement of antioxidant defense system in solvent tolerance of pseudomonas putida bcnu 106. | the highly solvent-tolerant bacterium pseudomonas sp. bcnu 106 was investigated to elucidate the solvent tolerance under specific culture conditions with the presence of solvents and its adaptive mechanisms to those conditions with reference to the antioxidant system. when exposed to 10% toluene, pseudomonas sp. bcnu 106 increased the generation of reactive oxygen species assessed by monitoring the oxidation of 2',7'-dichlorofluorescein. typical antioxidant enzymes (viz. catalase, superoxide dis ... | 2014 | 24136354 |
| gene expression profiling of pseudomonas putida f1 after exposure to aromatic hydrocarbon in soil by using proteome analysis. | pseudomonas putida f1 can metabolize toluene, ethylbenzene, and benzene for growth. previously, we identified proteins involved in the utilization of these compounds by p. putida f1 through culture in liquid media. however, it was unclear whether laboratory analysis of bacterial activity and catabolism accurately reflected the soil environment. we identified proteins involved in the degradation of toluene, ethylbenzene, and benzene growth in soil using two-dimensional gel electrophoresis (2-de) ... | 2013 | 24136143 |
| the crystal structure of pseudomonas putida azoreductase - the active site revisited. | the enzymatic degradation of azo dyes begins with the reduction of the azo bond. in this article, we report the crystal structures of the native azoreductase from pseudomonas putida met94 (ppazor) (1.60 å), of ppazor in complex with anthraquinone-2-sulfonate (1.50 å), and of ppazor in complex with reactive black 5 dye (1.90 å). these structures reveal the residues and subtle changes that accompany substrate binding and release. such changes highlight the fine control of access to the catalytic s ... | 2013 | 24127652 |
| model based evaluation of a contaminant plume development under aerobic and anaerobic conditions in 2d bench-scale tank experiments. | the influence of transverse mixing on competitive aerobic and anaerobic biodegradation of a hydrocarbon plume was investigated using a two-dimensional, bench-scale flow-through laboratory tank experiment. in the first part of the experiment aerobic degradation of increasing toluene concentrations was carried out by the aerobic strain pseudomonas putida f1. successively, ethylbenzene (injected as a mixture of unlabeled and fully deuterium-labeled isotopologues) substituted toluene; nitrate was ad ... | 2014 | 24122285 |
| the crc protein inhibits the production of polyhydroxyalkanoates in pseudomonas putida under balanced carbon/nitrogen growth conditions. | pseudomonas putida synthesizes polyhydroxyalkanoates (phas) as storage compounds. pha synthesis is more active when the carbon source is in excess and the nitrogen source is limiting, but can also occur at a lower rate under balanced carbon/nitrogen ratios. this work shows that pha synthesis is controlled by the crc global regulator, a protein that optimizes carbon metabolism by inhibiting the expression of genes involved in the use of non-preferred carbon sources. crc acts post-transcriptionall ... | 2014 | 24118893 |
| the effect of polyphosphate kinase gene deletion on polyhydroxyalkanoate accumulation and carbon metabolism in pseudomonas putida kt2440. | the primary enzyme involved in polyphosphate (polyp) synthesis, polyp kinase (ppk), has been deleted in pseudomonas putida kt2440. this has resulted in a threefold to sixfold reduction in polyhydroxyalkanoate (pha) accumulation compared with the wild type under conditions of nitrogen limitation, with either temperature or oxidative (h2o2) stress, when grown on glucose. the accumulation of pha by δppk mutant was the same as the wild type under nitrogen-limiting growth conditions. there was no dif ... | 2013 | 24115625 |
| new methods for the isolation and characterization of biofilm-persistent mutants in pseudomonas putida. | here we describe two new methods for the genetic characterization of bacterial biofilm development. first, we have designed a microtitre dish-based approach for high-throughput screening of pseudomonas putida mutants showing increased biofilm under dispersal conditions. using this method, nine such biofilm-persistent mutants, bearing transposon insertions in four loci: lapg, bifa, mvab and dksa, were isolated. second, we have developed a serial dilution-based scheme to monitor biofilm developmen ... | 2013 | 24115618 |
| impact of zno embedded feed spacer on biofilm development in membrane systems. | the concept of suppressing biofouling formation using an antibacterial feed spacer was investigated in a bench scale-cross flow system mimicking a spiral wound membrane configuration. an antibacterial composite spacer containing zinc oxide-nanoparticles was constructed by modification of a commercial polypropylene feed spacer using sonochemical deposition. the ability of the modified spacers to repress biofilm development on membranes was evaluated in flow-through cells simulating the flow condi ... | 2013 | 24079967 |
| hydroxylation of long chain fatty acids by cyp147f1, a new cytochrome p450 subfamily protein from streptomyces peucetius. | cytochrome p450 (cyp) 147f1 from streptomyces peucetius is a new cyp subfamily of that has been identified as ω-fatty acid hydroxylase. we describe the identification of cyp147f1 as a fatty acid hydroxylase by screening for the substrate using a substrate binding assay. screening of substrates resulted in the identification of fatty acid groups of compounds as potential hits for cyp147f1 substrates. fatty acids from c10:0 to c18:0 all showed type i shift spectra indicating their potential as sub ... | 2013 | 24055535 |
| a spatiotemporal view of plasmid loss in biofilms and planktonic cultures. | this commentary by madsen, burmølle, and sørensen discusses the article non-invasive in situ monitoring and quantification of tol plasmid segregational loss within pseudomonas putida biofilms by ma, katzenmeyer, and bryers. (2013. biotechnol bioeng. 110(11):2949-2958. doi: 10.1002/bit.24953). | 2013 | 24014288 |
| correlation of thermostability and conformational changes of catechol 2, 3-dioxygenases from two disparate micro-organisms. | we have investigated the structure of recombinant catechol 2, 3-dioxygenase (c23o) purified from two species in which the enzyme has evolved to function at different temperature. the two species are mesophilic bacterium pseudomonas putida strain mt-2 and thermophilic archaea sulfolobus acidocaldariusdsm639. using the primary sequence analysis, we show that both c23os have only 30% identity and 48% similarity but contain conserved amino acid residues forming an active site area around the iron io ... | 2013 | 23994541 |
| a chip-calorimetric approach to the analysis of ag nanoparticle caused inhibition and inactivation of beads-grown bacterial biofilms. | with the increasing complexity of model systems for the investigation of antibacterial effects of nanoparticles, the demands on appropriate analysis methods are rising. in case of biofilms grown on small particles, the high inhomogeneity of the samples represents a major challenge for traditional biofilm analysis. for this purpose, we developed a new calorimetric method which allows non-invasive and real-time investigation of the effects of nanoparticles on beads-grown biofilms which meets the r ... | 2013 | 23968644 |
| metabolic and regulatory rearrangements underlying glycerol metabolism in pseudomonas putida kt2440. | while the natural niches of the soil bacterium pseudomonas putida are unlikely to include significant amounts of free glycerol as a growth substrate, this bacterium is genetically equipped with the functions required for its metabolism. we have resorted to deep sequencing of the transcripts in glycerol-grown p. putida kt2440 cells to gain an insight into the biochemical and regulatory components involved in the shift between customary c sources (e.g. glucose or succinate) to the polyol. transcri ... | 2014 | 23967821 |
| breeding of a cyclic imide-assimilating bacterium, pseudomonas putida s52, for high efficiency production of pyruvate. | a succinimide-assimilating bacterium, pseudomonas putida s52, was found to be a potent producer of pyruvate from fumarate. using washed cells from p. putida s52 as catalyst, 400 mm pyruvate was produced from 500 mm fumarate in a 36-h reaction. bromopyruvate, a malic enzyme inhibitor, was used for the selection of mutants with higher pyruvate productivity. a bromopyruvate-resistant mutant, p. putida 15160, was found to be an effective catalyst for pyruvate production. moreover, under batch biorea ... | 2013 | 23924711 |
| miniaturised enzymatic conductometric biosensor with nafion membrane for the direct determination of formaldehyde in water samples. | a new conductometric enzyme-based biosensor was developed for the determination of formaldehyde (fa) in aqueous solutions. the biosensor was prepared by cross-linking formaldehyde dehydrogenase from pseudomonas putida with bovine serum albumin in saturated glutaraldehyde vapours (ga) at the surface of interdigitated gold microelectrodes. nicotinamide adenine dinucleotide cofactor (nad(+)) was added in solution at each measurement to maintain enzyme activity. addition of a nafion layer over the e ... | 2014 | 23907681 |
| swapping of phasin modules to optimize the in vivo immobilization of proteins to medium-chain-length polyhydroxyalkanoate granules in pseudomonas putida. | phaf is a bimodular protein of pseudomonas putida kt2442 exhibiting multiple functions within the polyhydroxyalkanoate (pha) apparatus. it behaves as phasin or pha granule binding protein (by biof domain) and also as nucleoid-associated protein involved in granule localization and segregation during cell division (by c-terminal domain). this work addresses the function of the phai phasin in the pha granule formation machinery. epifluorescence microscopy and flow cytometry studies of p. putida ph ... | 2013 | 23885896 |
| a combinatorial approach to the structure elucidation of a pyoverdine siderophore produced by a pseudomonas putida isolate and the use of pyoverdine as a taxonomic marker for typing p. putida subspecies. | the structure of a pyoverdine produced by pseudomonas putida, w15oct28, was elucidated by combining mass spectrometric methods and bioinformatics by the analysis of non-ribosomal peptide synthetase genes present in the newly sequenced genome. the only form of pyoverdine produced by p. putida w15oct28 is characterized to contain α-ketoglutaric acid as acyl side chain, a dihydropyoverdine chromophore, and a 12 amino acid peptide chain. the peptide chain is unique among all pyoverdines produced by ... | 2013 | 23877277 |
| biological production of monoethanolamine by engineered pseudomonas putida s12. | pseudomonas putida s12 was engineered for the production of monoethanolamine (mea) from glucose via the decarboxylation of the central metabolite l-serine, which is catalyzed by the enzyme l-serine decarboxylase (sdc). the host was first evaluated for its tolerance towards mea as well as its endogenous ability to degrade this alkanolamine. growth inhibition was observed at mea concentrations above 100 mm, but growth was never completely arrested even at 750 mm of mea. p. putida s12 was able to c ... | 2013 | 23876477 |
| genetic dissection of a motility-associated c-di-gmp signalling protein of pseudomonas putida. | lack of the pseudomonas putida pp2258 protein or its overexpression results in defective motility on solid media. the pp2258 protein is tripartite, possessing a pas domain linked to two domains associated with turnover of c-di-gmp - a cyclic nucleotide that controls the switch between motile and sessile lifestyles. the second messenger c-di-gmp is produced by diguanylate cyclases and degraded by phosphodiesterases containing ggdef and eal or hd-gyp domains respectively. it is common for enzymes ... | 2013 | 23864570 |
| engineering multicellular logic in bacteria with metabolic wires. | aromatic biodegradation pathways of environmental bacteria are vast sources of matching trios of enzymes, substrates and regulators that can be refactored to run logic operations through cell-to-cell communication. as a proof of concept, the connection between two pseudomonas putida strains using benzoic acid as the wiring molecule is presented. in this system, a sender strain harboring the tol pathway for biodegradation of aromatics processed toluene as input and generated benzoate as the outpu ... | 2014 | 23863114 |
| analysis of proteins expressed by an abiotic stress tolerant pseudomonas putida (nbaii-rpf9) isolate under saline and high temperature conditions. | pseudomonas putida (nbaii-rpf9) was identified as an abiotic stress tolerant bacterium capable of growing at 45 °c as well as in 1 m nacl. the proteins expressed by this bacterium when subjected to these two stresses were analyzed by 2d gel and maldi-tof/ms. two parameters viz., heat/saline shock (20 min at 45 °c/1 m solid nacl added at mid log phase and incubated for 1 h) and heat/saline tolerance (24 h growth at 45 °c/in 1 m nacl) were studied. under heat shock 13 upregulated proteins and 1 do ... | 2013 | 23828182 |
| amphipatic molecules affect the kinetic profile of pseudomonas putida chlorocatechol 1,2-dioxygenase. | dioxygenases are nonheme iron enzymes that biodegrade recalcitrant compounds, such as catechol and derivatives, released into the environment by modern industry. intradiol dioxygenases have attracted much attention due to the interest in their use for bioremediation, which has demanded efforts towards understanding their action mechanism and also how to control it. the role of unexpected amphipatic molecules, observed in crystal structures of intradiol dioxygenases, during catalysis has been poo ... | 2013 | 23754625 |
| identification and characterization of biosurfactants produced by the arctic bacterium pseudomonas putida bd2. | one hundred and thirty bacterial strains, isolated from arctic soil on the svalbard archipelago, were screened for biosurfactant production. among them, an isolate identified as pseudomonas putida bd2 was selected as a potential biosurfactant-producer based on the surface/interfacial activity of the culture supernatant. the ability of the strain to produce simultaneously phosphatidylethanolamines and rhamnolipid, using glucose as a sole carbon source, was demonstrated. the rhamnolipid rha-rha-c1 ... | 2013 | 23751417 |
| conservation of dark recovery kinetic parameters and structural features in the pseudomonadaceae "short" light, oxygen, voltage (lov) protein family: implications for the design of lov-based optogenetic tools. | in bacteria and fungi, various light, oxygen, voltage (lov) sensory systems that lack a fused effector domain but instead contain only short n- and c-terminal extensions flanking the lov core exist. in the prokaryotic kingdom, this so-called "short" lov protein family represents the third largest lov photoreceptor family. this observation prompted us to study their distribution and phylogeny as well as their photochemical and structural properties in more detail. we recently described the slow a ... | 2013 | 23746326 |
| pseudomonas putida kt2442 as a platform for the biosynthesis of polyhydroxyalkanoates with adjustable monomer contents and compositions. | the β-oxidation weakened pseudomonas putida were established as a platform for the production of polyhydroxyalkanoates (pha) with adjustable monomer compositions and micro-structures. when mutant p. putida ktoyo6δc (phapcja.c) was cultivated on mixtures of sodium butyrate and sodium hexanoate (c4:c6), random copolymers of p(3hb-co-3hhx) consisting of 3-hydroxybutyrate (3hb), 3-hydroxyhexanoate (3hhx), were accumulated with 3hhx content ranged from 19 mol% to 75 mol%. while recombinant p. putida ... | 2013 | 23743426 |
| the catabolism of 2,4-xylenol and p-cresol share the enzymes for the oxidation of para-methyl group in pseudomonas putida ncimb 9866. | pseudomonas putida ncimb 9866 utilizes p-cresol or 2,4-xylenol as a sole carbon and energy source. enzymes catalyzing the oxidation of the para-methyl group of p-cresol have been studied in detail. however, those responsible for the oxidation of the para-methyl group in 2,4-xylenol catabolism are still not reported. in this study, real-time quantitative pcr analysis indicated pchc- and pchf-encoded p-cresol methylhydroxylase (pcmh) and pcha-encoded p-hydroxybenzaldehyde dehydrogenase (phbdd) in ... | 2014 | 23736872 |
| a membrane-integrated advanced scheme for treatment of industrial wastewater: dynamic modeling towards scale up. | modeling and simulation was carried out for an advanced membrane-integrated hybrid treatment process that ensures reuse of water with conversion and recovery of ammoniacal nitrogen as value-added struvite fertilizer from coke wastewater. while toxic cyanide was largely removed in a pre-chemical treatment unit using fenton's reagents under optimized conditions, more than 95% of nh4(+)-n could be recovered as a valuable by-product called struvite through addition of appropriate doses of magnesium ... | 2013 | 23735488 |
| o-demethylations catalyzed by rieske nonheme iron monooxygenases involve the difficult oxidation of a saturated c-h bond. | dicamba monooxygenase (dmo) catalyzes the o-demethylation of dicamba (3,6-dichloro-2-methoxybenzoate) to produce 3,6-dichlorosalicylate and formaldehyde. recent crystallographic studies suggest that dmo catalyzes the challenging oxidation of a saturated c-h bond within the methyl group of dicamba to form a hemiacetal intermediate. testing of this hypothesis was made possible by our development of two new independent techniques. as a novel method to allow use of (18)o2 to follow reaction products ... | 2013 | 23719540 |
| transcriptional activation of the crcz and crcy regulatory rnas by the cbrb response regulator in pseudomonas putida. | the cbrab two-component system has been described as a high-ranked element in the regulatory hierarchy of pseudomonas putida that controls a variety of metabolic and behavioural traits required for adaptation to changing environmental conditions. we show that the response regulatory protein cbrb, an activator of σ(n) -dependent promoters, directly controls the expression of the small rnas crcz and crcy in p. putida. these two rnas sequester the protein crc, which is a translational repressor of ... | 2013 | 23692431 |
| characterization of olfactory sensilla of the olive fly: behavioral and electrophysiological responses to volatile organic compounds from the host plant and bacterial filtrate. | the responses of olive fly (bactrocera oleae) antennal and palpal olfactory receptors to odors emitted by pseudomonas putida bacterial filtrate and to volatiles from a host plant were evaluated using electrophysiological and behavioral bioassays. morphological identification of olfactory receptors was also performed. the third antennal segment (flagellum) bears four types of multiporous sensilla: trichoid, short basiconica, clavate and grooved. maxillary palps have mechanosensory bristles and mu ... | 2013 | 23669464 |
| inactivation of pseudomonas putida by pulsed electric field treatment: a study on the correlation of treatment parameters and inactivation efficiency in the short-pulse range. | an important issue for an economic application of the pulsed electric field treatment for bacterial decontamination of wastewater is the specific treatment energy needed for effective reduction of bacterial populations. the present experimental study performed in a field amplitude range of 40 > e > 200 kv/cm and for a suspension conductivity of 0.01 = κ(e) > 0.2 s/m focusses on the application of short pulses, 25 ns > t > 10 μs, of rectangular, bipolar and exponential shape and was made on pseud ... | 2013 | 23660812 |
| vaccination efficiency of surface antigens and killed whole cell of pseudomonas putida in large yellow croaker (pseudosciaena crocea). | large yellow croaker (pseudosciaena crocea), a major marine fish aquacultured in the southeastern coastal region of china, has become endangered by the pathogen pseudomonas putida in recent years. p. putida infections occur in low water temperatures when fish reduce food intake, thus oral antibiotic administration is not practical. therefore, vaccination may be the only method to prevent the infection. in the present study, main surface antigens of p. putida, including lipopolysaccharide (lps), ... | 2013 | 23659996 |
| bacterial invasion potential in water is determined by nutrient availability and the indigenous community. | in drinking water (dw) and the distribution systems, bacterial growth and biofilm formation have to be controlled both for limiting taste or odour development and preventing clogging or biocorrosion problems. after a contamination with undesired bacteria, factors like nutrient availability and temperature will influence the survival of these invaders. understanding the conditions enabling invaders to proliferate is essential for a holistic approach towards microbial risk assessment in dw. pseudo ... | 2013 | 23656310 |
| non-invasive in situ monitoring and quantification of tol plasmid segregational loss within pseudomonas putida biofilms. | methods for the detection of plasmid loss in natural environments have typically relied on replica plating, selective markers and pcr. however, these traditional methods have the limitations of low sensitivity, underestimation of specific cell populations, and lack of insightful data for non-homogeneous environments. we have developed a non-invasive microscopic analytical method to quantify local plasmid segregational loss from a bacterial population within a developing biofilm. the probability ... | 2013 | 23633286 |
| the contribution of proteomics to the unveiling of the survival strategies used by pseudomonas putida in changing and hostile environments. | pseudomonas putida is a ubiquitous, metabolically very versatile, gram-negative bacterium adapted to habitats as diverse as soil, water and the rhizosphere. most strains are nonpathogenic, many are used as experimental models, and many others have biotechnological applications in the areas of agriculture, bioremediation, biocatalysis, and the production of bioplastics. this review summarizes the contribution of proteomic technologies to our understanding of how p. putida responds to different ca ... | 2013 | 23625785 |
| biodegradation of 1-allyloxy-4-propoxybenzene by selected strains of pseudomonas putida. | dialkoxybenzenes constitute a class of organic compounds with anti feeding and oviposition effects on the cabbage looper, trichoplusia ni. among them, 1-allyloxy-4-propoxybenzene has the highest feeding deterrence activity and potential for development as commercial insect control agent. to develop this compound, its fate in the environment needs to be studied. the fate of organic compounds in the environment depends on their biodegradability in the soil. we present results of laboratory biodegr ... | 2014 | 23588837 |
| solubilization of phenanthrene above cloud point of brij 30: a new application in biodegradation. | in the present study a new application of solubilization of phenanthrene above cloud point of brij 30 in biodegradation was developed. it was shown that a temporal solubilization of phenanthrene above cloud point of brij 30 (5wt%) permitted to obtain a stable increase of the solubility of phenanthrene even when the temperature was decreased to culture conditions of used microorganism pseudomonas putida (28°c). a higher initial concentration of soluble phenanthrene was obtained after the cloud po ... | 2013 | 23582404 |
| identification of plant growth-promoting bacteria-responsive proteins in cucumber roots under hypoxic stress using a proteomic approach. | plant growth-promoting bacteria (pgpb) can both facilitate plant growth and improve plant resistance to a variety of environmental stresses. in order to investigate the mechanisms that pgpb use to protect plants under hypoxic conditions, the protein profiles of stressed and non-stressed cucumber roots, either treated or not treated with pgpb, were examined. two dimensional difference in-gel electrophoresis (dige) was used to detect significantly up- or down-regulated proteins (p<0.05, |ratio|>1. ... | 2013 | 23568019 |
| complex pathways for regulation of pyrimidine metabolism by carbon catabolite repression and quorum sensing in pseudomonas putida ru-km3s. | pseudomonads are metabolically versatile microbes that employ complex regulatory networks to control gene expression, particularly with respect to carbon and nitrogen metabolism. the aim of this study was to characterise the regulatory networks that control pyrimidine metabolism (hydantoin-hydrolysing activity) in pseudomonas putida strain ru-km3s, focussing on transcriptional activation of dihydropyrimidinase (dhp) and β-ureidopropionase (bup), encoding dhp and bup, respectively. the two genes ... | 2013 | 23563885 |
| interplay between extracellular matrix components of pseudomonas putida biofilms. | the extracellular matrix of bacterial biofilms has at least two key functions: to serve as a structural scaffold for the multicellular community, and to play a protective role against external stress. in this work, we report a compensatory effect whereby pseudomonas putida reacts to the lack of either of the two main surface proteins involved in biofilm formation, lapa and lapf, by increasing expression and production of a species-specific eps. elevated levels of the second messenger molecule cy ... | 2013 | 23562948 |
| interfacial interaction between methyl parathion-degrading bacteria and minerals is important in biodegradation. | in the present study, the influence of kaolinite and goethite on microbial degradation of methyl parathion was investigated. we observed that the biodegradation process was improved by kaolinite and depressed by goethite. calorimetric data further showed that the metabolic activities of degrading cells (pseudomonas putida) were enhanced by the presence of kaolinite and depressed by the presence of goethite. a semipermeable membrane experiment was performed and results supported the above observa ... | 2014 | 23549926 |
| the type ii secretion system (xcp) of pseudomonas putida is active and involved in the secretion of phosphatases. | the genome of the gram-negative bacterium pseudomonas putida harbours a complete set of xcp genes for a type ii protein secretion system (t2ss). this study shows that expression of these genes is induced under inorganic phosphate (pi ) limitation and that the system enables the utilization of various organic phosphate sources. a phosphatase of the phox family, previously designated uxpb, was identified, which was produced under low pi conditions and transported across the cell envelope in an xcp ... | 2013 | 23530902 |
| indole toxicity involves the inhibition of adenosine triphosphate production and protein folding in pseudomonas putida. | high concentrations of indole are known to be toxic to cells due to perturbations in membrane potential. here, we report for the first time a transcriptome analysis of a soil model bacterium, pseudomonas putida kt2440, under indole treatment. we demonstrated that 47 genes are differentially expressed, including 11 genes involved in the tricarboxylic acid cycle (tca cycle) and 12 genes involved in chaperone and protease functions (hslv, hslu, htpg, grpe, dnak, ibpa, groel, groes, clpb, lon-1, lon ... | 2013 | 23527579 |
| in silico protein structure modeling and conservation analysis of chrr, a class-i chromate reducing flavoenzyme from pseudomonas putida. | hexavalent chromium [cr(vi)] is a widespread environmental pollutant, arising as a by-product of numerous industrial processes. bacteria can reduce toxic and carcinogenic cr(vi) to insoluble and less toxic cr(iii), offering promise for an environmental friendly and affordable solution to chromate pollution. chrr, a class i chromate-reducing flavoenzyme from pseudomonas putida is an efficient chromate reducer. the crystal structure of chrr is yet unknown to the scientific community, hence a three ... | 2013 | 23517724 |
| impact of nitrate dose on toluene degradation under denitrifying condition. | in this study, we investigated the impact of nitrate dose on toluene degradation by pseudomonas putida to elucidate the upper limit of nitrate concentration and whether an optimum ratio of nitrate to toluene concentration exists. batch microcosm studies were conducted in order to monitor toluene degradation for various ratios (2-20) of nitrate to toluene with nitrate concentrations ranging from 0 to 700 mg l(-1) for a given toluene concentration of 50 and 25 mg l(-1) during 4-day (short term) an ... | 2013 | 23504564 |
| real-time pcr for rapidly detecting aniline-degrading bacteria in activated sludge. | we developed a detection method that uses quantitative real-time pcr (qpcr) and the taqman system to easily and rapidly assess the population of aniline-degrading bacteria in activated sludge prior to conducting a biodegradability test on a chemical compound. a primer and probe set for qpcr was designed by a multiple alignment of conserved amino acid sequences encoding the large (α) subunit of aniline dioxygenase. pcr amplification tests showed that the designed primer and probe set targeted ani ... | 2013 | 23466276 |
| chip-calorimetric monitoring of biofilm eradication with antibiotics provides mechanistic information. | increased antibiotic resistance of pathogenic bacteria dwelling in biofilm structures has motivated the development of various monitoring tools specifically designed for biofilm investigations. in this study, the potential of the recently emerging chip calorimetry for this purpose was analysed. the activity of biofilms of pseudomonas putida paw340 was monitored chip-calorimetrically and compared with counts of colony forming units (cfu), bioluminescence-based atp measurements, and quantitative c ... | 2013 | 23453494 |
| effect of carbon sources and of sulfate on microbial arsenic mobilization in sediments of west bengal, india. | arsenic (as) dissolution from sediments into groundwater in the bengal delta/west india was investigated. two experimental sites were choosen with contrasting as concentrations in shallow groundwater. apparently patches of high-as and low-as sediments occured in close neigbourhood. a fast as mobilization with lactate or ethanol as carbon sources and sulfate as an electron acceptor and a possible influence of indigenous flora because of higher as amounts and an increasing total cell count was obs ... | 2013 | 23453350 |
| pseudomonas putida are environmental reservoirs of antimicrobial resistance to β-lactamic antibiotics. | the adaptive flexibility of bacteria largely contributes to the emergence of antibiotic resistance, eventually leading to the predictable failure of current antimicrobial therapies. it is of utmost importance to improve current approaches and implement new ways to control bacterial growth and proliferation. a promising strategy lies in unraveling the antimicrobial resistance (amr) dynamics in environmental reservoirs, namely in soil. environmental microorganisms are antibiotic producers and gene ... | 2013 | 23420114 |
| influence of periplasmic oxidation of glucose on pyoverdine synthesis in pseudomonas putida s11. | fluorescent pseudomonads catabolize glucose simultaneously by two different pathways, namely, the oxidative pathway in periplasm and the phosphorylative pathway in cytoplasm. this study provides evidence for the role of glucose metabolism in the regulation of pyoverdine synthesis in pseudomonas putida s11. we have characterized the influence of direct oxidation of glucose in periplasm on pyoverdine synthesis in p. putida s11. we identified a tn5 transposon mutant of p. putida s11 showing increas ... | 2013 | 23392768 |
| integrating grant-funded research into the undergraduate biology curriculum using img-act. | it has become clear in current scientific pedagogy that the emersion of students in the scientific process in terms of designing, implementing, and analyzing experiments is imperative for their education; as such, it has been our goal to model this active learning process in the classroom and laboratory in the context of a genuine scientific question. toward this objective, the national science foundation funded a collaborative research grant between a primarily undergraduate institution and a r ... | 2013 | 23382122 |
| bacteriostatic effect of sequential hydrodynamic and ultrasound-induced stress. | to elucidate the mechanism of action of a nonchemical microbial control technology employing coupled hydrodynamic and ultrasound-induced stress. | 2013 | 23360068 |
| effects of surfactants on cell surface tension parameters and hydrophobicity of pseudomonas putida 852 and rhodococcus erythropolis 3586. | the interaction between bacteria and surfaces is central to many environmental, industrial and medical applications. surfactants are commonly used in these applications and can potentially influence the bacterium/surface interaction. the effect of surfactants upon bacterial cell surface thermodynamic properties was examined using a combination of contact angle measurements and lw-ab surface free energy calculation. two bacterial strains, hydrophilic pseudomonas putida 852 and hydrophobic rhodoco ... | 2013 | 23352946 |
| structural and computational studies of the maleate isomerase from pseudomonas putida s16 reveal a breathing motion wrapping the substrate inside. | nicotine is an environmental toxicant in tobacco waste, imposing a serious hazard for human health. some bacteria including pseudomonas spp. strains are able to metabolize nicotine to non-toxic compounds. the pyrrolidine pathway of nicotine degradation in pseudomonas putida s16 has recently been revealed. the maleate isomerase (pp-iso) catalyses the last step in nicotine degradation of p. putida s16, the cis-trans isomerization of maleate to fumarate. in this study, we determined the crystal str ... | 2013 | 23347155 |
| the anti-cancer activity of a cationic anti-microbial peptide derived from monomers of polyhydroxyalkanoate. | the biodegradable polymer medium chain length polyhydroxyalkanoate (mclpha), produced by pseudomonas putida ca-3, was depolymerised and the predominant monomer (r)-3-hydroxydecanoic acid (r10) purified. r10 was conjugated to a d-peptide dp18 and its derivatives. all peptides conjugated with r10 exhibited greater anti-cancer activity compared to the unconjugated peptides. unconjugated and conjugated peptides were cytocidal for cancer cells. conjugation of r10 to peptides was essential for enhance ... | 2013 | 23343631 |
| [isolation identification and characterization of halotolerant petroleum-degrading bacteria]. | to obtain efficient halotolerant petroleum-degrading bacteria, 39 bacteria strains were isolated from 30 petroleum contaminated saline soil samples in yellow river delta, an important base of petroleum production in china. one bacterium (strain bm38) was found to efficiently degrade crude oil in highly saline environments based on a series of liquid and soil incubation experiments. according to its morphology, physiochemical characteristics and 16s rdna sequence analysis, this strain was identif ... | 2012 | 23323430 |
| evidence for self-association of the alternative sigma factor σ54. | sigma factor σ(54) has a distinct modus operandi for mediating the activation of bacterial rna polymerase (rnap) at promoter recognition motifs 12 and 24 bp upstream from transcription start sites. σ(54) was thought to act as monomer in all transcription steps. however, we provide evidence that σ(54) of pseudomonas putida interacts stably with itself. the interface between monomers involves contacts in σ(54) regions i and iii, sequences that play key roles in the transcription activation of σ(54 ... | 2013 | 23320542 |
| characterization and mass spectrometry analysis of aminopeptidase n from pseudomononas putida lup. | an intracellular aminopeptidase n synthesized by pseudomonas putida lup was purified and characterized. the approx. 150-fold purified enzyme showed highest activity against a-beta-naphthylamide at ph 7.5 and at temperature 40 degrees c and was 100% thermostable for 240 min at 40 degrees c. p putida lup aminopeptidase n is a monomer with molecular mass approx. 99 kda determined by sds-page and gel permeation chromatography. the enzyme has broad substrate specificity, but is the most active agains ... | 2013 | 24730126 |
| effect of complexing ligands on the surface adsorption, internalization, and bioresponse of copper and cadmium in a soil bacterium, pseudomonas putida. | environmental quality criteria for metals toxic to soil and water organisms, using the free ion activity model or the biotic ligand model, are based on the concept that the major form of the metal available to the organism is the free metal ion, yet various metal complexes are bioavailable to a variety of soil and water organisms. we test here whether neutral copper or cadmium sulfates, negatively-charged copper or cadmium citrates and positively-charged copper acetate and cadmium chloride are b ... | 2013 | 23270705 |
| pseudomonas putida kt2440 response to nickel or cobalt induced stress by quantitative proteomics. | nickel and cobalt are obligate nutrients for the gammaproteobacteria but when present at high concentrations they display toxic effects. these two metals are present in the environment, their origin being either from natural sources or from industrial use. in this study, the effect of inhibitory concentrations of ni or co was assessed on the soil bacterium pseudomonas putida kt2440 using a proteomic approach. the identification of more than 400 spots resulted in the quantification of 160 protein ... | 2013 | 23235558 |
| reward for bdellovibrio bacteriovorus for preying on a polyhydroxyalkanoate producer. | bdellovibrio bacteriovorus hd100 is an obligate predator that invades and grows within the periplasm of gram-negative bacteria, including mcl-polyhydroxyalkanoate (pha) producers such as pseudomonas putida. we investigated the impact of prey pha content on the predator fitness and the potential advantages for preying on a pha producer. using a new procedure to control p. putida kt2442 cell size we demonstrated that the number of bdellovibrio progeny depends on the prey biomass and not on the via ... | 2013 | 23227863 |
| preparation of activated carbon from dried pods of prosopis cineraria with zinc chloride activation for the removal of phenol. | utilization of agrowaste materials for the production of activated carbon, as an excellent adsorbent with large surface area, is well established industrially, for dephenolation of wastewater. in the present work, dried pods of prosopis cineraria-a novel and low-cost agrowaste material-were used to prepare activated carbons by zinc chloride activation. batch adsorption experiments were carried out to study the effects of various physicochemical parameters such as initial phenol concentration, ad ... | 2013 | 23212266 |
| investigating the role of protein unkg from the pseudomonas putida uw4 in the ability of the bacterium to facilitate plant growth. | a previous study showed that overexpressing protein unkg decreased the ability of the plant growth-promoting bacterium pseudomonas putida uw4 to facilitate plant growth and an unkg knockout mutant of p. putida uw4 displayed increased plant growth promotion. when activities of wild-type and the unkg overexpressing strain, including growth rates, carbon utilization, cell size, 3-indoleacetic acid production, and 1-aminocyclopropane-1-carboxylate deaminase activity, were measured, there were no app ... | 2013 | 23212206 |
| analysis of the plant growth-promoting properties encoded by the genome of the rhizobacterium pseudomonas putida bird-1. | pseudomonas putida bird-1 is a plant growth-promoting rhizobacterium whose genome size is 5.7 mbp. it adheres to plant roots and colonizes the rhizosphere to high cell densities even in soils with low moisture. this property is linked to its ability to synthesize trehalose, since a mutant deficient in the synthesis of trehalose exhibited less tolerance to desiccation than the parental strain. the genome of bird-1 encodes a wide range of proteins that help it to deal with reactive oxygen stress g ... | 2013 | 23206161 |
| human cell death in relation to dna damage after exposure to the untreated and biologically treated pharmaceutical wastewater. | among all the pharmaceutical drugs that contaminate the environment, antibiotics occupy an important place due to their high consumption rates in both veterinary and human medicine. the present study examined the ability of pseudomonas putida to grow on the antibiotic wastewater, currently expanding in tunisia, containing amoxicillin and cefadroxil. p. putida was very efficient to grow quickly in pharmaceutical wastewater (pw) and in reducing the total dissolved solids to 80.1 %. cytotoxicity of ... | 2013 | 23179225 |
| the tol network of pseudomonas putida mt-2 processes multiple environmental inputs into a narrow response space. | the tol system encoded by plasmid pww0 of pseudomonas putida mt-2 is able to sense a large number of both exogenous and endogenous signals as inputs for the genetic and metabolic circuit that determines the biodegradation of m-xylene. however, whether the enormous combinatorial space of inputs is translated into an equally variable response landscape or is processed into very few outcomes remains unclear. to address this question, we set out to define the number of states that can be obtained by ... | 2013 | 23171249 |
| in-silico-driven metabolic engineering of pseudomonas putida for enhanced production of poly-hydroxyalkanoates. | here, we present systems metabolic engineering driven by in-silico modeling to tailor pseudomonas putida for synthesis of medium chain length phas on glucose. using physiological properties of the parent wild type as constraints, elementary flux mode analysis of a large-scale model of the metabolism of p. putida was used to predict genetic targets for strain engineering. among a set of priority ranked targets, glucose dehydrogenase (encoded by gcd) was predicted as most promising deletion target ... | 2013 | 23164576 |
| tactic responses to pollutants and their potential to increase biodegradation efficiency. | a significant number of bacterial strains are able to use toxic aromatic hydrocarbons as carbon and energy sources. in a number of cases, the evolution of the corresponding degradation pathway was accompanied by the evolution of tactic behaviours either towards or away from these toxic carbon sources. reports are reviewed which show that a chemoattraction to heterogeneously distributed aromatic pollutants increases the bioavailability of these compounds and their biodegradation efficiency. an ex ... | 2013 | 23163356 |