| insights into the function of rifi2: structural and biochemical investigation of a new shikimate dehydrogenase family protein. | the shikimate dehydrogenase (sdh) family consists of enzymes with diverse roles in secondary metabolism. the two most widespread members of the family, aroe and ydib, function in amino acid biosynthesis and quinate catabolism, respectively. here, we have determined the crystal structure of an sdh homolog belonging to the rifi class, a group of enzymes with proposed roles in antibiotic biosynthesis. the structure of rifi2 from pseudomonas putida exhibits a number of distinctive features, includin ... | 2013 | 23142411 |
| downstream processing, characterization, and structure-function relationship of solvent-, detergent-, psychro-, thermo-, alkalistable metalloprotease from metal-, solvent-tolerant psychrotrophic pseudomonas putida skg-1 isolate. | the purification and characterization of psychro-thermoalkalistable protease from psychrotrophic pseudomonas putida isolate is being reported for the first time. a ~53 kda protease was purified 21.4-folds with 57.2% recovery by ultrafiltration and hydrophobic interaction chromatography. kinetic analyses revealed the k(m) and v(max) to be 1.169 mg ml(-1) and 0.833 mg ml(-1) min(-1) , respectively. the k(cat) value of 3.05 × 10(2) s(-1) indicated high affinity and catalytic efficiency toward casei ... | 2013 | 23125172 |
| identification of eps-degrading activity within the tail spikes of the novel pseudomonas putida phage af. | we report the study of phage af, the first member of the canonical lambdoid phage group infecting pseudomonas putida. its 42.6 kb genome is related to the "epsilon15-like viruses" and the "bpp-1-like viruses", a clade of bacteriophages shaped by extensive horizontal gene transfer. the af virions display exopolysaccharide (eps)-degrading activity, which originates from the action of the c-terminal domain of the tail spike (gp19). this protein shows high similarity to the tail spike of the t7-like ... | 2012 | 23084421 |
| eukaryotic-type aromatic amino acid decarboxylase from the root colonizer pseudomonas putida is highly specific for 3,4-dihydroxyphenyl-l-alanine, an allelochemical in the rhizosphere. | aromatic amino acid decarboxylases (aadcs) are found in various organisms and play distinct physiological roles. aadcs from higher eukaryotes have been well studied because they are involved in the synthesis of biologically important molecules such as neurotransmitters and alkaloids. in contrast, bacterial aadcs have received less attention because of their simplicity in physiology and in target substrate (tyrosine). in the present study, we found that pseudomonas putida kt2440 possesses an aadc ... | 2012 | 23059975 |
| degradation of cationic surfactants using pseudomonas putida a atcc 12633 immobilized in calcium alginate beads. | in this study, the degradation of tetradecyltrimethylammonium bromide (ttab) by freely suspended and alginate-entrapped cells from the bacteria pseudomonas putida (p. putida) a atcc 12633 was investigated in batch cultures. the optimal conditions to prepare beads for achieving a higher ttab degradation rate were investigated by changing the concentration of sodium alginate, ph, temperature, agitation rate and initial concentration of ttab. the results show that the optimal embedding conditions o ... | 2013 | 23054181 |
| construction and characterization of nitrate and nitrite respiring pseudomonas putida kt2440 strains for anoxic biotechnical applications. | pseudomonas putida kt2440 is frequently used in biotechnical research and applications due to its metabolic versatility and organic solvent resistance. a major drawback for a broad application is the inability of the bacterium to survive and grow under anoxic conditions, which prohibits the production of oxygen-sensitive proteins and metabolites. to develop a p. putida strain, which is able to survive under anoxic conditions, the enzymatic systems of anaerobic nitrate and nitrite respiration wer ... | 2013 | 23036925 |
| genome-wide analytical approaches using semi-quantitative expression proteomics for aromatic hydrocarbon metabolism in pseudomonas putida f1. | pseudomonas putida f1 can degrade aromatic hydrocarbons to intermediate products of the tricarboxylic acid cycle. to determine key induced proteins and enzymes required for degradation of toluene, ethylbenzene, benzene, p-cymene, and p-cumate, we performed comprehensive proteome analysis using a combination of 1-d sds-page and lc-ms/ms in cells grown in the presence of each aromatic hydrocarbon. semi-quantitative analysis using protein content calculated from the exponentially modified protein a ... | 2012 | 23022446 |
| bioremoval of basic violet 3 and acid blue 93 by pseudomonas putida and its adsorption isotherms and kinetics. | basic violet 3 and acid blue 93 are the most important group of synthetic colourants extensively used in textile industries for dyeing cotton, wool, silk and nylon. release of these dye pollutants in to the environment adversely affects the human health and aquatic organisms. the present study we used pseudomonas putida mtcc 4910 for the adsorptive removal of basic violet 3 and acid blue 93 from the aqueous solutions. the ph (4-9) and nacl concentrations (1mm-1m) did not influence the adsorption ... | 2013 | 23010121 |
| isolation and characterization of bacteria from mercury contaminated sites in rio grande do sul, brazil, and assessment of methylmercury removal capability of a pseudomonas putida v1 strain. | methylmercury (mehg) is one of the most dangerous heavy metal for living organisms that may be found in environment. given the crescent industrialization of brazil and considering that mercury is a residue of several industrial processes, there is an increasing need to encounter and develop remediation approaches of mercury contaminated sites. the aim of this study was to isolate and characterize methylmercury resistant bacteria from soils and sludge sewage from rio grande do sul, brazil. sixtee ... | 2013 | 22983740 |
| biofiltration of ethyl acetate by pseudomonas putida immobilized on walnut shell. | a biofilter packed with walnut shells was used to eliminate ethyl acetate from an air stream. the shells treated with naoh were used as medium for immobilization of pseudomonas putida ptcc 1694. at an empty bed residence time (ebrt) of 60s, a removal efficiency of 99% was achieved at inlet concentrations lower than 430ppm of ethyl acetate. the removal efficiency decreased below 80% with an increase in inlet concentration of ethyl acetate. when the ebrt was increased to 75 s, the removal efficien ... | 2012 | 22940351 |
| control of phytophthora nicotianae disease, induction of defense responses and genes expression of papaya fruits treated with pseudomonas putida mgp1. | biological control is a potential strategy to reduce post-harvest decay in several fruits. little research has been carried out on the effects of endophytic bacterium on post-harvest blight caused by phytophthora nicotianae in papaya. in this work, the biocontrol activity of pseudomonas putida mgp1 on this disease and its possible mechanisms, including changes of defensive enzyme activities, total phenolic content and mrna levels of two important genes, were investigated. | 2013 | 22936430 |
| a rapid electrochemical procedure for the detection of hg(0) produced by mercuric-reductase: application for monitoring hg-resistant bacteria activity. | in this work, gold microelectrodes are employed as traps for the detection of volatilized metallic mercury produced by mercuric reductase (mera) extracted from an hg-resistant pseudomonas putida strain fb1. the enzymatic reduction of hg (ii) to hg (0) was induced by nadph cofactor added to the samples. the amount of hg(0) accumulated on the gold microelectrode surface was determined by anodic stripping voltammetry (asv) after transferring the gold microelectrode in an aqueous solution containing ... | 2012 | 22928857 |
| the translational repressor crc controls the pseudomonas putida benzoate and alkane catabolic pathways using a multi-tier regulation strategy. | metabolically versatile bacteria usually perceive aromatic compounds and hydrocarbons as non-preferred carbon sources, and their assimilation is inhibited if more preferable substrates are available. this is achieved via catabolite repression. in pseudomonas putida, the expression of the genes allowing the assimilation of benzoate and n-alkanes is strongly inhibited by catabolite repression, a process controlled by the translational repressor crc. crc binds to and inhibits the translation of ben ... | 2013 | 22925411 |
| pari, an orphan para family protein from pseudomonas putida kt2440-specific genomic island, interferes with the partition system of incp-7 plasmids. | pseudomonas putida kt2440 is an ideal soil bacterium for expanding the range of degradable compounds via the recruitment of various catabolic plasmids. in the course of our investigation of the host range of incp-7 catabolic plasmids pcar1, pdk1 and pww53, we found that the incp-7 miniplasmids composed of replication and partition loci were exceptionally unstable in kt2440, which is the authentic host of the archetypal incp-9 plasmid pww0. this study identified pari, a homologue of para family o ... | 2012 | 22925377 |
| reactions between bacterial exopolymers and goethite: a combined macroscopic and spectroscopic investigation. | the adsorption to goethite of extracellular polymeric substances (eps) isolated from pseudomonas putida was investigated using batch adsorption experiments, electrophoretic mobility (em) measurements, fourier transform infrared (ftir) spectroscopy, isothermal titration calorimetry (itc) and x-ray absorption fine structure (xafs) spectroscopy. the adsorption of eps decreased the point of zero charge of goethite from 7.6 to 3.2, suggesting the formation of negatively charged inner-sphere surface c ... | 2012 | 22921391 |
| homologous recombination is facilitated in starving populations of pseudomonas putida by phenol stress and affected by chromosomal location of the recombination target. | homologous recombination (hr) has a major impact in bacterial evolution. most of the knowledge about the mechanisms and control of hr in bacteria has been obtained in fast growing bacteria. however, in their natural environment bacteria frequently meet adverse conditions which restrict the growth of cells. we have constructed a test system to investigate hr between a plasmid and a chromosome in carbon-starved populations of the soil bacterium pseudomonas putida restoring the expression of phenol ... | 2012 | 22917545 |
| biochemical characterization of ferredoxin-nadp(+) reductase interaction with flavodoxin in pseudomonas putida. | flavodoxin (fld) has been demonstrated to bind to ferredoxin- nadp(+) reductase a (fpra) in pseudomonas putida. two residues (phe(256), lys(259)) of fpra are likely to be important for interacting with fld based on homology modeling. sitedirected mutagenesis and ph-dependent enzyme kinetics were performed to further examine the role of these residues. the catalytic efficiencies of fpra-ala(259) and fpra-asp(259) proteins were two-fold lower than those of the wild-type fpra. homology modeling als ... | 2012 | 22917033 |
| biodegradation of btex mixture by pseudomonas putida yns1 isolated from oil-contaminated soil. | the presence of mixed contaminants, such as btex (benzene, toluene, ethylbenzene and xylene isomers) can affect the biodegradation, fate and environmental impacts of each compound. to understand the influence of interactions among btex compounds on their biodegradation, four bacteria were isolated from oil-contaminated soil and assayed for btex biodegradation in vitro. the isolate exhibiting maximum biodegradation was identified as pseudomonas putida based on the 16s rdna sequence. the biodegrad ... | 2013 | 22915285 |
| less is more: reduced catechol production permits pseudomonas putida f1 to grow on styrene. | pseudomonas putida f1 is unable to grow on styrene due to the accumulation of 3-vinylcatechol, a toxic metabolite that is produced through the toluene degradation (tod) pathway and causes catechol-2,3-dioxygenase (c23o) inactivation. in this study, we characterized a spontaneous f1 mutant, designated sf1, which acquired the ability to grow on styrene and did not accumulate 3-vinylcatechol. whereas adaptation to new aromatic substrates has typically been shown to involve increased c23o activity o ... | 2012 | 22902727 |
| cointegrate-resolution of toluene-catabolic transposon tn4651: determination of crossover site and the segment required for full resolution activity. | tn3-family transposon tn4651 from pseudomonas putida mt-2 plasmid pww0 carries two divergently transcribed genes, tnps and tnpt, for cointegrate-resolution. while tnps encodes a tyrosine recombinase, tnpt encodes a protein that shows no homology to any other characterized protein. the tn4651 resolution site was previously mapped within the 203-bp fragment that covered the tnps and tnpt promoter region. to better understand the molecular mechanisms underlying the tn4651 cointegrate-resolution, we ... | 2013 | 22878084 |
| biosynthesis and properties of medium-chain-length polyhydroxyalkanoates with enriched content of the dominant monomer. | when grown in a nonanoic acid-limited chemostat at a dilution rate of 0.25 h(-1), pseudomonas putida kt2440 produced poly(3-hydroxynonanoate-co-3-hydroxyheptanoate) containing 68 mol % 3-hydroxynonanoate (c9) and 32 mol % 3-hydroxyheptanoate (c7). under the same conditions, but in the presence of acrylic acid, a fatty acid β-oxidation inhibitor, the c9 monomer content increased to 88 mol %. cofeeding glucose (3.9 g l(-1)) and nonanoic acid (2.9 ± 0.1 g l(-1)) in continuous culture with 0.2 g l(- ... | 2012 | 22871146 |
| pentachlorophenol dechlorination and simultaneous cr6+ reduction by pseudomonas putida skg-1 mtcc (10510): characterization of pcp dechlorination products, bacterial structure, and functional groups. | it is the first report in which a novel psychrotrophic pseudomonas putida skg-1 strain was evaluated for simultaneous bioremediation of pentachlorophenol and cr(6+) under various cultural and nutritional conditions. pentachlorophenol (pcp) dechlorination products, bacterial structure, and functional groups were characterized by gas chromatography and mass spectrometry (gc-ms), scanning electron microscope and energy dispersive x-ray spectroscopy (sem-eds), and fourier-transform infrared (ftir) t ... | 2013 | 22864755 |
| biofouling control by quorum sensing inhibition and its dependence on membrane surface. | biofouling control by quorum sensing (qs) inhibition and the influence of membrane surface characteristics on biofilm formation and qs inhibition were investigated. pseudomonas putida isolated from the bio-fouled reverse osmosis (ro) membranes in a real plant was used. acylase was chosen as a model qs inhibitor. bacteria on the membrane coupons were quantified with the heterotrophic plate count method. cell distribution was imaged by a confocal laser scanning microscope. results showed that biof ... | 2012 | 22864426 |
| stochasticity of tol plasmid catabolic promoters sets a bimodal expression regime in pseudomonas putida mt-2 exposed to m-xylene. | the expression dynamics of the catabolic promoters of the tol plasmid pww0 has been examined in single cells of pseudomonas putida mt-2 exposed to m-xylene. to this end, we employed an á la carte bi-cistronic gfp-lacz reporter system for generating monocopy transcriptional fusions to each of the four promoters (pr, ps, pu and pm) of the regulatory network. whereas expression of xylr (the master regulatory gene of the tol system) behaved in a unimodal fashion, the activation of pu and pm displaye ... | 2012 | 22845424 |
| influence of siderophore pyoverdine synthesis and iron-uptake on abiotic and biotic surface colonization of pseudomonas putida s11. | fluorescent pseudomonads produce a characteristic fluorescent pigment, pyoverdines as their primary siderophore for iron acquisition under iron-limiting conditions. here, we report the identification of a random transposon mutant ist3 of pseudomonas putida s11 showing tolerance to iron starvation stress condition and increased pyoverdine production. the insertion of the tn5 transposon was found to be in psts gene of pstsr operon encoding sensor histidine kinase protein of the two-component signa ... | 2012 | 22821204 |
| analysis of solvent tolerance in pseudomonas putida dot-t1e based on its genome sequence and a collection of mutants. | pseudomonas putida strains are prevalent in a variety of pristine and polluted environments. the genome of the solvent-tolerant p. putida strain dot-t1e which thrives in the presence of high concentrations of monoaromatic hydrocarbons, contains a circular 6.3 mbp chromosome and a 133 kbp plasmid. omics information has been used to identify the genes and proteins involved in solvent tolerance in this bacterium. this strain uses a multifactorial response that involves fine-tuning of lipid fluidity ... | 2012 | 22819823 |
| bacterial rna extraction and purification from whole human blood using isotachophoresis. | we demonstrate a novel assay for physicochemical extraction and isotachophoresis-based purification of 16s rrna from whole human blood infected with pseudomonas putida . this on-chip assay is unique in that the extraction can be automated using isotachophoresis in a simple device with no moving parts, it protects rna from degradation when isolating from ribonuclease-rich matrices (such as blood), and produces a purified total nucleic acid sample that is compatible with enzymatic amplification as ... | 2012 | 22816776 |
| aerobic degradation of 3-chlorobenzoic acid by an indigenous strain isolated from a polluted river. | an indigenous strain of pseudomonas putida capable of degrading 3-chlorobenzoic acid as the sole carbon source was isolated from the riachuelo, a polluted river in buenos aires. aerobic biodegradation assays were performed using a 2-l microfermentor. biodegradation was evaluated by spectrophotometry, chloride release, gas chromatography and microbial growth. detoxification was evaluated by using vibrio fischeri, pseudokirchneriella subcapitata and lactuca sativa as test organisms. the indigenous ... | 2012 | 22805844 |
| characterization of a strain of pseudomonas putida isolated from agricultural soil that degrades cadusafos (an organophosphorus pesticide). | bacteria capable of degrading the pesticide, cadusafos, were isolated from agricultural soil using an enrichment method. in this way, five distinct cadusafos-degrading strains of pseudomonas putidia were isolated, and were characterized using morphological and biochemical analysis, as well as 16s rrna sequencing. strain pc1 exhibited the greatest cadusafos degradation rate and was consequently selected for further investigation. degradation of cadusafos by strain pc1 was rapid at 20 and 37°c, bu ... | 2012 | 22805799 |
| kinetics of medium-chain-length polyhydroxyalkanoate production by a novel isolate of pseudomonas putida ls46. | six bacteria that synthesize medium-chain-length polyhydroxyalkanoates (mcl-phas) were isolated from sewage sludge and hog barn wash and identified as strains of pseudomonas and comamonas by 16s rdna gene sequencing. one isolate, pseudomonas putida ls46, showed good pha production (22% of cell dry mass) in glucose medium, and it was selected for further studies. while it is closely related to other p. putida strains (f1, kt2440, bird-1, gb-1, s16, and w619), p. putida ls46 was genetically distin ... | 2012 | 22804681 |
| pseudomonas putida response to cadmium: changes in membrane and cytosolic proteomes. | pseudomonas putida is a saprophytic bacterium with remarkable environmental adaptability and the capacity to tolerate high concentrations of heavy metals. the strain p. putida-cd001 was isolated from soil contaminated with cd, zn and pb. membrane-associated and cytosolic proteomes were analyzed to identify proteins whose expression was modulated in response to 250 μm cdso4. we identified 44 protein spots in the membrane and 21 in the cytosolic fraction differentially expressed in cd-treated samp ... | 2012 | 22799892 |
| the role of amino acid residues in the active site of l-methionine γ-lyase from pseudomonas putida. | cys116, lys240*, and asp241* (asterisks indicate residues from the second subunit of the active dimer) at the active site of l-methionine γ-lyase of pseudomonas putida (mgl_pp) are highly conserved among heterologous mgls. in a previous study, we found that substitution of cys116 for his led to a drastic increase in activity toward l-cysteine and a decrease in that toward l-methionine. in this study, we examined some properties of the c116h mutant by kinetic analysis and 3d structural analysis. ... | 2012 | 22785484 |
| chronic ecotoxic effects to pseudomonas putida and vibrio fischeri, and cytostatic and genotoxic effects to the hepatoma cell line (hepg2) of ofloxacin photo(cata)lytically treated solutions. | ofloxacin (ofl), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. the elimination of ofl and other xenobiotics by the application of advanced oxidation processes using photolytic (pl) and photocatalytic (pc) treatments seems promising. however, an integrated assessment scheme is needed, in ... | 2013 | 22743217 |
| the role of residue s139 of mandelate racemase: synergistic effect of s139 and e317 on transition state stabilization. | mandelate racemase (mr) from pseudomonas putida catalyzes the specific carbon-hydrogen bond cleavage of carbon acids with high pk(a) values. to further explore the catalytic mechanism of mr, "hot spots" contributing to transition state (ts) stabilization were identified by molecular dynamics (md) simulations. md simulations of mr with mandelic acid interpreted s139 in the active site cavity formed a hydrogen bond (hb) with one carboxyl oxygen of mandelate which also interacts with e317 through h ... | 2012 | 22731931 |
| high rate biological nutrient removal from high strength wastewater using anaerobic-circulating fluidized bed bioreactor (a-cfbbr). | biological nutrient removal (bnr) from high strength wastewater was investigated using a newly developed integrated anaerobic fluidized bed (af) with circulating fluidized bed bioreactor henceforth called a-cfbbr. the a-cfbbr showed 99.7%cod removal, 84% nitrogen removal, with a very low sludge yield of 0.017 g vss/g cod while treating a synthetic wastewater containing 10,700 mg cod/l and 250 mg nh(3)-n/l over a period of 6 months. the system was operated at an organic loading rate (olr) of 35 k ... | 2012 | 22717573 |
| cra regulates the cross-talk between the two branches of the phosphoenolpyruvate : phosphotransferase system of pseudomonas putida. | the gene that encodes the catabolite repressor/activator, cra (frur), of pseudomonas putida is divergent from the frubka operon for the uptake of fructose via the phosphoenolpyruvate : carbohydrate phosphotransferase system (pts(fru)). the expression of the fru cluster has been studied in cells growing on substrates that change the intracellular concentrations of fructose-1-p (f1p), the principal metabolic intermediate that counteracts the dna-binding ability of cra on an upstream operator. whil ... | 2013 | 22708906 |
| performance and microbial community in hybrid anaerobic baffled reactor-constructed wetland for nitrobenzene wastewater. | a process combining an anaerobic baffled reactor (abr) and a constructed wetland was employed to treat nitrobenzene wastewater. the overall performance was examined throughout long-term operation with a hydraulic retention time (hrt) of 24 h at 30±1 °c. the effluent nitrobenzene concentration of the abr and constructed wetland was less than 4.81 and 1.94 mg/l, respectively, with an initial nitrobenzene concentration of 80 mg/l at the steady-state periods. the corresponding removal efficiencies w ... | 2012 | 22705515 |
| the role of glpr repressor in pseudomonas putida kt2440 growth and pha production from glycerol. | pseudomonas putida kt2440 has evolved a tightly regulated system for metabolizing glycerol implying a prolonged growth lag-phase. we have learnt that this fact can be avoided by the addition of small amounts of some growth precursors. the addition of 1 mm octanoic acid as co-feeder completely eliminated the lag-phase, resulting in an improvement, in terms of invested time, of both growth and polyhydroxyalkanoates (pha) accumulation. to investigate this phenomenon, we have followed co-metabolic a ... | 2013 | 22646161 |
| chemical effectors cause different motile behavior and deposition of bacteria in porous media. | we tested the hypothesis whether chemically induced motility patterns of bacteria may affect their transport in porous media. naphthalene-degrading pseudomonas putida g7 cells were exposed to glucose, salicylate, and silver nanoparticles (agnps) and their motility was assessed by computer-assisted, quantitative swimming and capillary-based taxis determinations. exposure to salicylate induced smooth movement with few acceleration events and positive taxis, whereas cells exposed to agnps exhibited ... | 2012 | 22642849 |
| adhesion of nano-sized particles to the surface of bacteria: mechanistic study with the extended dlvo theory. | due to the increasing production and application of nanoparticles, their release into the environment would be inevitable, which requires a better understanding of their fate in the environment. when considering their toxic behavior or biodegradation as their fate, their adhesion to the cell surface must be the first step to be thoroughly studied. in this study, nano-sized polymeric particles of urethane acrylate with various hydrophobicity and ionic properties were synthesized as model nanopart ... | 2012 | 22609594 |
| broadening the signal specificity of prokaryotic promoters by modifying cis-regulatory elements associated with a single transcription factor. | in this report, we experimentally demonstrate that improving the cis-regulatory region of a target promoter can significantly enhance the response to an otherwise poor inducer. the transcriptional factor (tf) benr of pseudomonas putida kt2440 is a member of the arac/xyls family that activates the pb promoter in response to benzoate. this tf can also trigger pb activity in response to 3-methylbenzoate (3mbz), but with lower efficiency. unlike other family members, benr appears to recognize one op ... | 2012 | 22588473 |
| development of a bioprocess to convert pet derived terephthalic acid and biodiesel derived glycerol to medium chain length polyhydroxyalkanoate. | sodium terephthalate (ta) produced from a pet pyrolysis product and waste glycerol (wg) from biodiesel manufacture were supplied to pseudomonas putida go16 in a fed-batch bioreactor. six feeding strategies were employed by altering the sequence of ta and wg feeding. p. putida go16 reached 8.70 g/l cell dry weight (cdw) and 2.61 g/l pha in 48 h when grown on ta alone. when ta and wg were supplied in combination, biomass productivity (g/l/h) was increased between 1.3- and 1.7-fold and pha producti ... | 2012 | 22581066 |
| [destruction of mustard gas hydrolysis products by marine and soil bacteria]. | destruction of mustard gas hydrolysis products by bacterial cultures isolated from soils and bottom waters at the sites of chemical weapons disposal has been studied. among the tested microorganisms, the soil bacteria pseudomonas putida y-21 and rhodococcus erythropolis 8d and the marine bacteria achromobacter sp. 75-1, arthrobacter sp. 23-3, and pseudomonas sp. 93-2 show the highest activity. thiodiglycol is utilized by two pathways; one of them, with formation of [(2-hydroxyethyl)thio]acetic a ... | 2016 | 22567876 |
| identification of novel members reveals the structural and functional divergence of lepidopteran-specific lipoprotein_11 family. | 30k proteins (30kps) are classified into the lepidopteran-specific lipoprotein_11 family. they are involved in various physiological processes such as energy storage, embryonic development, and immune response in the silkworm. to date, 30kps were only found in bombyx mori and manduca sexta. moreover, the c-termini of enf peptide binding proteins (enf-bps) show similarity to 30kps. enf peptides are multifunctional insect cytokines and involved in growth regulation and defense reaction, whereas en ... | 2012 | 22534768 |
| are leaf glandular trichomes of oregano hospitable habitats for bacterial growth? | phyllospheric bacteria were isolated from microsites around essential-oil-containing glands of two oregano (origanum vulgare subsp. hirtum) lines. these bacteria, 20 isolates in total, were subjected to bioassays to examine their growth potential in the presence of essential oils at different concentrations. although there were qualitative and quantitative differences in the essential oil composition between the two oregano lines, no differences were recorded in their antibacterial activity. in ... | 2012 | 22527057 |
| modeling of permeabilization process in pseudomonas putida g7 for enhanced limonin bioconversion. | a facile process of enhanced whole cell biotransformation to debitter the triterpenoid limonin in citrus juices was optimized in this work. to maximize bioconversion, permeabilization conditions were modeled using response surface methodology. a central composite rotatable design with four significant variables (concentration, temperature, ph, and treatment time) was employed. the second order polynomial equations with r² values above 0.9 showed good correspondence between experimental and predi ... | 2012 | 22526774 |
| the ihf regulon of exponentially growing pseudomonas putida cells. | integration host factor (ihf) sites are largely absent from intergenic regions of orfs encoding central metabolic functions in pseudomonas putida mt-2. to gain an insight into this unequal distribution of otherwise abundant ihf-binding sequences, the transcriptome of ihf-plus and ihf-minus cells growing exponentially on glucose as sole carbon source was examined. in parallel, the cognate metabolic fluxes of the wild-type p. putida strain and its ihfa derivative were determined by culturing cells ... | 2013 | 22510163 |
| two identical nonylphenol monooxygenase genes linked to is6100 and some putative insertion sequence elements in sphingomonas sp. np5. | sphingomonas sp. np5 can degrade a wide range of nonylphenol (np) isomers that have widely contaminated aquatic environments as major endocrine-disrupting chemicals. to understand the biochemical and genetic backgrounds of np degradation, a gene library of strain np5 was constructed using a broad-host-range vector pbbr1mcs-2 and introduced into sphingobium japonicum ut26. several transformants accumulated reddish brown metabolites on agar plates dispersed with a mixture of np isomers. two differ ... | 2012 | 22504436 |
| assessment of the metabolic capacity and adaptability of aromatic hydrocarbon degrading strain pseudomonas putida csv86 in aerobic chemostat culture. | pseudomonas putida csv86 utilizes aromatic compounds preferentially over sugars and co-metabolizes aromatics along with organic acids. in the present study, the metabolic capacity and adaptability of strain csv86 were assessed in a chemostat at benzyl alcohol concentrations ranging from 1 g l(-1) to 3 g l(-1) and in the presence of glucose and succinate by systematically varying the dilution rate. complete removal of benzyl alcohol was achieved for loadings up to 640 mg l(-1) h(-1) in presence o ... | 2012 | 22494573 |
| dynamics of ahl mediated quorum sensing under flow and non-flow conditions. | quorum sensing (qs) describes the capability of microbes to communicate with each other by the aid of small molecules. here we investigate the dynamics of qs-regulated gene expression induced by acylhomoserine lactones (ahls) in pseudomonas putida isof containing a green fluorescent protein-based ahl reporter. the fluorescence time course of individual colonies is monitored following the external addition of a defined ahl concentration to cells which had previously reached the qs-inactive state ... | 2012 | 22476057 |
| development of a visual loop-mediated isothermal amplification method for rapid detection of the bacterial pathogen pseudomonas putida of the large yellow croaker (pseudosciaena crocea). | in recent years, the large yellow croaker (pseudosciaena crocea), an important marine fish farmed in the coastal areas of zhejiang province, east china, has become severely endangered as a result of the bacterial pathogen pseudomonas putida. this paper reports the development of a visual loop-mediated isothermal amplification (lamp) assay for rapid detection of the pathogen. four primers, f3, b3, fip and bip, were designed on the basis of dna sequence of the rpon gene of p. putida. after optimiz ... | 2012 | 22475582 |
| transcriptional control of the main aromatic hydrocarbon efflux pump in pseudomonas. | bacteria of the species pseudomonas putida are ubiquitous soil inhabitants, and a few strains are able to thrive in the presence of extremely high concentrations of toxic solvents such as toluene and related aromatic hydrocarbons. toluene tolerance is multifactorial in the sense that bacteria use a wide range of physiological and genetic changes to overcome solvent damage. this includes enhanced membrane impermeabilization through cis to trans isomerization of unsaturated fatty acids, activation ... | 2012 | 23757269 |
| dependence of the initial adhesion of biofilm forming pseudomonas putida mt2 on physico-chemical material properties. | bacterial adhesion is strongly dependent on the physico-chemical properties of materials and plays a fundamental role in the development of a growing biofilm. selected materials were characterized with respect to their physico-chemical surface properties. the different materials, glass and several polymer foils, showed a stepwise range of surface tensions (γ(s)) between 10.3 and 44.7 mn m(-1). measured zeta potential values were in the range between -74.8 and -28.3 mv. the initial bacterial adhe ... | 2012 | 22452391 |
| heterologous expression and genetic engineering of the tubulysin biosynthetic gene cluster using red/et recombineering and inactivation mutagenesis. | although the tubulysin (tub) biosynthetic gene cluster has been located in two myxobacterial strains, it appears in both cases to be incomplete as obvious candidates for acyl transfer and oxidation functions are lacking. here, we report the engineering of a heterologous expression system for the tub biosynthetic pathway from strain cystobacter sp. sbcb004. the entire tub core cluster was reconstituted from two cosmids using red/et recombineering and heterologous expression achieved in strains ps ... | 2012 | 22444591 |
| growth kinetic models for phenol biodegradation in a batch culture of pseudomonas putida. | biodegradation of phenol with pure culture of pseudomonas putida was investigated. p. putida (ptcc 1694) was grown in facultative anaerobic condition at 27 degrees c and media ph value of 7. the effect of initial phenol concentration on the biodegradation rate was studied. the initial concentrations of phenol varied from 300 to 1000 mg/l. experiments were performed for the duration of seven days while daily samples were withdrawn. the initial rate of biodegradation of phenol increased with initi ... | 2011 | 22439571 |
| impact of fluorochrome stains used to study bacterial transport in shallow aquifers on motility and chemotaxis of pseudomonas species. | one of the most common methods of tracking movement of bacteria in groundwater environments involves a priori fluorescent staining. a major concern in using these stains to label bacteria in subsurface injection-and-recovery studies is the effect they may have on the bacterium's transport properties. previous studies investigated the impact of fluorophores on bacterial surface properties (e.g. zeta potential). however, no previous study has looked at the impact of fluorescent staining on swimmin ... | 2012 | 22404159 |
| integrated organic-aqueous biocatalysis and product recovery for quinaldine hydroxylation catalyzed by living recombinant pseudomonas putida. | in an earlier study, biocatalytic carbon oxyfunctionalization with water serving as oxygen donor, e.g., the bioconversion of quinaldine to 4-hydroxyquinaldine, was successfully achieved using resting cells of recombinant pseudomonas putida, containing the molybdenum-enzyme quinaldine 4-oxidase, in a two-liquid phase (2lp) system (ütkür et al. j ind microbiol biotechnol 38:1067-1077, 2011). in the study reported here, key parameters determining process performance were investigated and an efficie ... | 2012 | 22383177 |
| chemoenzymatic formal synthesis of (-)- and (+)-epibatidine. | the cis-dihydrocatechol, derived from enzymatic cis-dihydroxylation of bromobenzene using the microorganism pseudomonas putida uv4, was converted into (-)-epibatidine in eleven steps with complete stereocontrol. in addition, an unprecedented palladium-catalysed disproportionation reaction gave the (+)-enantiomer of an advanced key intermediate employed in a previous synthesis of epibatidine. | 2012 | 22367429 |
| pseudomonas putida growing at low temperature shows increased levels of crcz and crcy srnas, leading to reduced crc-dependent catabolite repression. | the crc protein of pseudomonas inhibits the expression of genes involved in the transport and assimilation of a number of non-preferred carbon sources when preferred substrates are available, thus coordinating carbon metabolism. crc acts by binding to target mrnas, inhibiting their translation. in pseudomonas putida, the amount of free crc available is controlled by two srnas, crcy and crcz, which bind to and sequester crc. the levels of these srnas vary according to metabolic conditions. pseudo ... | 2013 | 22360597 |
| membrane changes associated with exposure of pseudomonas putida to selected environmental pollutants and their possible roles in toxicity. | a bacterial model system (pseudomonas putida dsm 50026) was used in this research to assess potential effect of five selected chemically diverse environmental pollutants on cell membranes. long chain fatty acid profiles of cultures exposed to environmentally relevant concentrations of atrazine (atr), metolachlor (met), pentachlorobiphenyl (pcb), hexachlorobenzene (hcb) and fluoranthene (fl), were analyzed and compared to non-exposed cultures. to assess sensitivity of membrane-based responses, th ... | 2012 | 24061176 |
| effects of bacterial acc deaminase on brassica napus gene expression. | plants in association with plant growth-promoting rhizobacteria can benefit from lower plant ethylene levels through the action of the bacterial enzyme 1-aminocyclopropane-1-carboxylic acid (acc) deaminase. this enzyme cleaves the immediate biosynthetic precursor of ethylene, acc. ethylene is responsible for many aspects of plant growth and development but, under stressful conditions, it exacerbates stress symptoms. the acc deaminase-containing bacterium pseudomonas putida uw4 is a potent plant ... | 2012 | 22352713 |
| pseudomonas putida infection of the conjunctiva. | | 2012 | 22350960 |
| toluene dioxygenase expression correlates with trichloroethylene degradation capacity in pseudomonas putida f1 cultures. | trichloroethylene (tce) is extensively used in commercial applications, despite its risk to human health via soil and groundwater contamination. the stability of tce, which is a useful characteristic for commercial application, makes it difficult to remove it from the environment. numerous studies have demonstrated that tce can be effectively removed from the environment using bioremediation. pseudomonas putida f1 is capable of degrading tce into less hazardous byproducts via the toluene dioxyge ... | 2012 | 22350420 |
| industrial biotechnology of pseudomonas putida and related species. | since their discovery many decades ago, pseudomonas putida and related subspecies have been intensively studied with regard to their potential application in industrial biotechnology. today, these gram-negative soil bacteria, traditionally known as well-performing xenobiotic degraders, are becoming efficient cell factories for various products of industrial relevance including a full range of unnatural chemicals. this development is strongly driven by systems biotechnology, integrating systems m ... | 2012 | 22350258 |
| the phosphatidylcholine synthase of pseudomonas putida a atcc 12633 is responsible for the synthesis of phosphatidylcholine, which acts as a temporary reservoir for al3+. | in pseudomonas putida a atcc 12633 cells grown with tetradecyltrimethylammonium bromide and exposed to al(3)cl, phosphatidylcholine (pc) levels increased, which alleviated stress caused by the al(3+). here we cloned and sequenced a gene from this strain that encodes a phosphatidylcholine synthase (pcs) and characterized a pcs-deficient mutant. in the pcs-deficient mutant, pc could not be detected, whereas the mutant could be successfully complemented and expressed the enzyme, indicating that pc ... | 2012 | 22343357 |
| construction and application of a zinc-specific biosensor for assessing the immobilization and bioavailability of zinc in different soils. | the inducibility and specificity of different czcrs operons in pseudomonas putida x4 were studied by lacz gene fusions. the data of β-glycosidase activity confirmed that the czcr3 promoter responded quantitatively to zinc. a zinc-specific biosensor, p. putida x4 (pczcr3gfp), was constructed by fusing a promoterless enhanced green fluorescent protein (egfp) gene with the czcr3 promoter in the chromosome of p. putida x4. in water extracts of four different soils amended with zinc, the reporter str ... | 2012 | 22336732 |
| use of an uncertainty analysis for genome-scale models as a prediction tool for microbial growth processes in subsurface environments. | the integration of genome-scale, constraint-based models of microbial cell function into simulations of contaminant transport and fate in complex groundwater systems is a promising approach to help characterize the metabolic activities of microorganisms in natural environments. in constraint-based modeling, the specific uptake flux rates of external metabolites are usually determined by michaelis-menten kinetic theory. however, extensive data sets based on experimentally measured values are not ... | 2012 | 22335464 |
| structural basis for the slow dark recovery of a full-length lov protein from pseudomonas putida. | blue-light photoreceptors containing light–oxygen–voltage (lov) domains regulate a myriad of different physiological responses in both eukaryotes and prokaryotes. their light sensitivity is intricately linked to the photochemistry of the non-covalently bound flavin mononucleotide (fmn) chromophore that forms a covalent adduct with a conserved cysteine residue in the lov domain upon illumination with blue light. all lov domains undergo the same primary photochemistry leading to adduct formation; ... | 2012 | 22326872 |
| pseudomonas putida nbric19 dihydrolipoamide succinyltransferase (sucb) gene controls degradation of toxic allelochemicals produced by parthenium hysterophorus. | the aim of this study was to identify the gene responsible for degradation of toxic allelochemicals of parthenium by generating tn5-induced mutant of pseudomonas putida nbric19. furthermore, the study characterizes the mutant at physiological, biochemical and molecular level that helped in understanding the mechanisms of reducing the allelopathic inhibition of parthenium by ps. putida nbric19. | 2012 | 22324517 |
| responses of pseudomonas putida to toxic aromatic carbon sources. | a number of bacteria can use toxic compounds as carbon sources and have developed complex regulatory networks to protect themselves from the toxic effects of these compounds as well as to benefit from their nutritious properties. as a model system we have studied the responses of pseudomonas putida strains to toluene. although this compound is highly toxic, several strains are able to use it for growth. particular emphasis was given to the responses in the context of taxis, resistance and toluen ... | 2012 | 22321573 |
| bioremediation of industrial pharmaceutical drugs. | recently, attention has been drawn toward the occurrence of pharmaceuticals in the environment. in recent years, many reports have been made on the occurrence of the large, differentiated group of pharmaceuticals in wastewater (pw), surface water, ground water, and in soil. the pharmaceutical sector is currently expanding in tunisia, with more than 34 industries. the aim of this work was to evaluate the ability of pseudomonas putida mt-2 to treat pw. p. putida was very efficient in reducing chem ... | 2012 | 22313387 |
| [toxic and mutagenic influence of hexachlorocyclohexane and its microbial destruction products on soil microbial cenosis]. | microbial strains pseudomonas putida 9, stenotrophomonas maltophilia imv b-7288 destructed hexachlorcyclohexane (hch) isomers complex by 31.1-76.6 and 30.7-73.2%. respectively, in comparison with given level. hch and its destruction intermediates had toxic and mutagenic influence on soil microbial associations decreasing their survival to 6.9-21.7%. the investigated destruction products and intermediates obtained by pseudomonas putida 9, stenotrophomonas maltophilia imv b-7288 have demonstrated ... | 2013 | 22308752 |
| [construction of hg(2+)-induced luminescent reporter gene system and its application to detect mercury in red soil]. | a luminescent reporter gene system was constructed by fusing the mercury-inducible promoter, p(mert), and its regulatory gene, merr with a promoterless reporter gene egfp. a stable whole-cell reporter was created by mini-tn5 and introducing the merr-egfp system cassette into the chromosome of pseudomonas putida strain, then applied it for mercury detection in the red soil of jiangxi province, the fluorescence density of the sensor strain was confirmed in soil extraction and fluorescence intensit ... | 2011 | 22279922 |
| kinetics of hydrolysis and mutational analysis of n,n-diethyl-m-toluamide hydrolase from pseudomonas putida dtb. | the initial step in the biodegradation pathway of n,n-diethyl-m-toluamide (deet) in pseudomonas putida strain dtb is catalyzed by deet hydrolase (dtha), which hydrolyzes the amide bond to yield 3-methylbenzoic acid and diethylamine. in order to extend our understanding of dtha, the enzyme was purified and characterized. the enzyme is most active at ph 7.9, and is probably a tetramer in its native state. the kinetic parameters of the wild-type enzyme are k(m) = 10.2 ± 0.8 μm, k(cat) = 5.53 ± 0.09 ... | 2012 | 22251573 |
| purification and characterization of ddt-dehydrohalogenase from pseudomonas putida t5. | ddt-dehydrohalogenase is involved in the catalytic degradation of p,p'-ddt by eliminating either hcl or cl(-) to form ddd/dde. isolation, purification and characterization of ddt-dehydrohalogenase from a bacterial source is reported in this manuscript. ten bacterial cultures belonging to ddt degrading microbial consortium were screened for the ddt-dehydrohalogenase activity. among these, the clarified cell homogenate of pseudomonas putida t5 showed higher ddt-dehydrohalogenase activity and enzym ... | 2012 | 22239708 |
| simultaneous removal of phosphorus and nitrogen in a sequencing batch biofilm reactor with transgenic bacteria expressing polyphosphate kinase. | to improve phosphorus removal from wastewater, we constructed a high-phosphate-accumulating microorganism, ktppk, using pseudomonas putida kt2440 as a host. the expression plasmid was constructed by inserting and expressing polyphosphate kinase gene (ppk) from microcystis aeruginosa nies-843 into broad-host-range plasmid, pbbr1mcs-2. ktppk was then added to a sequencing batch biofilm reactor (sbbfr) using lava as a biological carrier. the results showed that sbbfr with ktppk not only efficiently ... | 2012 | 22218771 |
| bacterial tactic response to silver nanoparticles. | in this study, we investigated the tactic response of pseudomonas putida g7, a representative soil bacterium, towards silver nanoparticles (agnps). the study integrated the characterization of surface area and size distribution of agnps, toxicity determinations, based on atp production, and assessment of the repellent reaction by means of an inverted capillary assay ('chemical-in-pond' method), and changes in the motility behaviour determined by computer-assisted motion analysis. our data demons ... | 2011 | 23761331 |
| growth of pseudomonas putida at low temperature: global transcriptomic and proteomic analyses. | in its natural habitats (soil, water and rhizosphere), pseudomonas putida can suffer frequent and long-term changes in temperature that affect its growth and survival. pseudomonas putida kt2440, a well-characterized model strain, grows optimally at 30°c but can proliferate at temperatures as low as 4°c. however, little information is available on the physiological changes that occur when p. putida grows at low temperatures. to investigate this area, the transcriptome and proteome profiles of cel ... | 2011 | 23761279 |
| ppor, an orphan luxr-family protein of pseudomonas putida kt2440, modulates competitive fitness and surface motility independently of n-acylhomoserine lactones. | pseudomonas putida kt2440 does not produce any of the common molecules involved in quorum sensing signalling described in other bacteria. however, as is the case in other microorganisms, the genome of this strain contains an open reading frame (pp_4647) coding for a transcriptional regulator belonging to the luxr protein family. in this article, we present evidence indicating that this protein, named ppor, modulates swarming motility in kt2440 and plays a role in the survival of this strain in t ... | 2011 | 23761234 |
| isolation and genetic characterization of an improved benzene-tolerant mutant of pseudomonas putida s12. | pseudomonas putida s12.49, a mutant stain of p. putida s12 that tolerates up to 20 mm benzene, was obtained by evolutionary selection. the genetic basis for the strongly enhanced benzene tolerance was investigated by proteome and transcriptome analysis. indications were found that the highly benzene-tolerant phenotype is the resultant of multi-level systemic changes. the solvent extrusion pump srpabc was constitutively expressed in p. putida s12.49, which could be attributed to the disruption of ... | 2010 | 23766120 |
| functional analysis of new transporters involved in stress tolerance in pseudomonas putida dot-t1e. | pseudomonas putida dot-t1e is a highly solvent-tolerant strain. although the main mechanism that confers solvent tolerance to the strain is the ttgghi efflux pump, a number of other proteins are also involved in the response to toluene. previous proteomic and transcriptomic analysis carried out in our lab with p. putida dot-t1e, and the solvent-sensitive strain, p. putida kt2440, revealed several transporters that were induced in the presence of toluene. we prepared five mutants of the correspon ... | 2010 | 23766111 |
| pseudomonas putida kt2440 causes induced systemic resistance and changes in arabidopsis root exudation. | pseudomonas putida kt2440 is an efficient colonizer of the rhizosphere of plants of agronomical and basic interest. we have demonstrated that kt2440 can protect the model plant arabidopsis thaliana against infection by the phytopathogen pseudomonas syringae pv. tomato dc3000. p. putida extracellular haem-peroxidase (pp2561) was found to be important for competitive colonization and essential for the induction of plant systemic resistance. root exudates of plants elicited by kt2440 exhibited dist ... | 2010 | 23766110 |
| physiological and transcriptomic characterization of a flia mutant of pseudomonas putida kt2440. | pseudomonas putida kt2440 encodes 23 alternative sigma factors. the flia gene, which encodes σ(28) , is in a cluster with other genes involved in flagella biosynthesis and chemotaxis. reverse transcriptase-pcr revealed that this cluster is comprised of four independent transcriptional units: flhaf, flenflia, cheyza and chebmotab. we generated a nonpolar flia mutant by homologous recombination and tested its motility, adhesion to biotic and abiotic surfaces, and responses to various stress condit ... | 2010 | 23766109 |
| a general profile for the merr family of transcriptional regulators constructed using the semi-automated provalidator tool. | provalidator is a web-based tool that facilitates the design and validation of generalized profiles of protein families in prokaryotes. this tool combines the nearly full automation of profile building with a search for family members in all available databases. the tool is useful for assigning a given protein to a specific family, and is also useful for genome mining in annotated prokaryotic genomes. the tool is freely available at http://www.bactregulators.org. as proof of concept we construct ... | 2009 | 23765930 |
| in vivo role of fdhd and fdme in formate metabolism in pseudomonas putida: redundancy and expression in the stationary phase. | in pseudomonas putida two open reading frames (orfs) pp0257 and pp0492 were originally annotated as accessory formate dehydrogenase proteins. the orf pp0492 (fdmd) is at the 3' end of the orf pp0489 through pp0491 operon that encodes one of the formate dehydrogenases of p. putida and it is transcribed with this operon preferentially at the stationary phase. the orf pp0257 (fdhd) is unlinked to formate dehydrogenase clusters and, as to multi-component formate dehydrogenases, pp0257 is also prefer ... | 2009 | 23765795 |
| deterioration of tolerance to hydrophobic organic solvents in a toluene-tolerant strain of pseudomonas putida under the conditions lowering aerobic respiration. | the growth curve (increase in the number of viable cells) of a toluene-tolerant strain pseudomonas putida px51t was not reproducible in the presence of harmful organic solvents, such as p-xylene and toluene. the survival often fluctuated the during late exponential phase of growth. the repetitive growth was obtained by maintaining po2 20-40% (v/v) in the culture flask. however, even under these aerobic conditions, the cells starved for a carbon source were killed by exposure to harmful solvents. ... | 1999 | 27389504 |
| characterization of quinohemoprotein amine dehydrogenase from pseudomonas putida. | quinohemoprotein amine dehydrogenase (amdh) was purified and crystallized from the soluble fraction of pseudomonas putida ifo 15366 grown on n-butylamine medium. amdh gave a single component in analytical ultracentrifugation showing an intrinsic sedimentation coefficient of 5.8s. amdh showed a typical absorption spectrum of cytochrome c showing maxima at 554, 522, 420, and 320 nm in the reduced form and one peak at 410 nm, a shoulder at 350 nm, and a broad hill around 530 nm in the oxidized form ... | 1998 | 27315927 |
| biodegradation of 3-chlorobenzoate by pseudomonas putida 10.2. | pseudomonas putida 10.2, a 3-chlorobenzoate (3cba)-degrading bacterium, was isolated from a soil sample obtained from an agricultural area in chiang mai, thailand. this bacterium could degrade 2mm 3cba very rapidly with the concomitant formation of chloride ion when grown in mineral salt-yeast extract medium. the presence of glucose, lactose and pyruvate in the medium reduced the capability of this bacterium to degrade 3cba. metabolites such as 3-chlorocatechol (3cc), catechol and cis,cis-muconi ... | 1996 | 24415423 |
| removal of caffeine in sewage by pseudomonas putida: implications for water pollution index. | a strain of pseudomonas putida (biotype a) capable of growing on caffeine (1,3,7-trimethylxanthine) was isolated from a domestic wastewater processing operation. it used caffeine as the sole carbon source with a mean growth rate constant (k) of 0.049 h(-1) (approximately 20 h per generation), whereas k for glucose utilization under similar incubation conditions was 0.31 (3.3 h per generation). the isolate contained at least two plasmids, and the increased expression of a 40 kda protein was attri ... | 1996 | 24415233 |
| short communication: isolation of a bacterium capable of limited degradation of industrial and labelled, natural and synthetic lignins. | pseudomonas putida, isolated from decomposing plant materials, degraded several lignin-related aromatic compounds. after 30 days of incubation in media containing polymeric kraft-lignin (pkl), the amount of klason lignin had decreased by about 13%. when (14)c-labelled dehydropolymers of coniferyl alcohol (dhp) lignins and (14)c-lignin-lignocelluloses were used as substrates, mineralization to (14)co2 by the p. putida strain ranged from 1.4% to 2.1%. | 1996 | 24415105 |
| effect of endogenous methylglyoxal on chinese hamster ovary cells grown in culture. | methylglyoxal is a ketoaldehyde that reacts readily under physiological conditions with biologically relevant ligands, such as amine and sulfhydryl groups. it is produced in mammalian cells primarily as a by-product of glycolysis. the level of glucose, l-glutamine and fetal bovine serum in culture media was found to significantly affect levels of intracellular methylglyoxal in chinese hamster ovary cells. medium with 25 mm glucose and 5 mm l-glutamine caused an increase in free methylglyoxal lev ... | 1996 | 22358913 |
| fate of pseudomonas putida after release into lake water mesocosms: different survival mechanisms in response to environmental conditions. | to study the fate of pseudomonas putida dsm 3931 in an aquatic environment, cultures of the strain were released into lake water mesocosms. p. putida, bearing the tol-plasmid, was released as a representative xenobiotic-degrading microorganism. the release was carried out in mesocosms with unamended lake water and in lake water with added culture medium to compare the survival of the strain due to the influence of different organic load. as a comparison, the survival of p. putida was followed in ... | 1994 | 24190270 |
| degradation of nitriles and amides by the immobilized cells of pseudomonas putida. | pseudomonas putida, capable of utilizing acetonitrile as a sole source of c and n, was immobilized in calcium alginate and the rates of degradation of nitriles, including acetonitrile, and their respective amides were studied. all the organic nitriles and amides tested were converted into nh3 and co2. | 1993 | 24420117 |
| biological removal of inorganic hg(ii) as gaseous elemental hg(0) by continuous culture of a hg-resistant pseudomonas putida strain fb-1. | a strain of broad-spectrum, mercury-resistant pseudomonas putida fb1 was used to remove mercury as the gaseous element (hg(0)) from a continuous axenic culture, fed with a synthetic medium containing 1 mg hg l(-1) as hgcl2. mercury determinations were performed in steady-state cultures using various culture fractions [whole culture, filtered supernatant, bacterial cells (dry wt), recovery trap liquid] in order to determine the removal efficiency at different dilution rates (from 0.1 to 3.0 day(- ... | 1993 | 24419964 |
| a plant selectable marker gene based on the detoxification of the herbicide dalapon. | a gene from pseudomonas putida coding for a dehalogenase capable of degrading 2,2 dichloropropionic acid (2,2dcpa), the active ingredient of the herbicide dalapon, has been isolated and characterised. in plant transformation experiments the gene was shown to confer resistance to 2,2dcpa at a tissue culture level where 2,2dcpa could be used to select for transformants. at the whole plant level, transformed plants showed resistance to 2,2dcpa at concentrations up to 5 times the recommended dose ra ... | 1992 | 24213366 |
| long-term survival of and plasmid stability inpseudomonas andklebsiella species and appearance of nonculturable cells in agricultural drainage water. | one year after introduction into agricultural drainage waterpseudomonas fluorescens r2f (rp4),pseudomonas putida cym318 (prk2501), andklebsiella aerogenes nctc418 (pbr322) could be recovered on agar media. survival of the introduced strains depended on competition with the indigenous microflora, the presence of nutrients, and the availability of air.in contrast tok. aerogenes nctc418 (pbr322), bothpseudomonas species lost their plasmids, as indicated by the consistently lower colony counts on se ... | 1990 | 24196361 |
| thiosulfate oxidation by obligately heterotrophic bacteria. | thiosulfate was oxidized stoichiometrically to tetrathionate during growth on glucose byklebsiella aerogenes, bacillus globigii, b. megaterium, pseudomonas putida, two strains each ofp. fluorescens andp. aeruginosa, and anaeromonas sp. a gram-negative, rod-shaped soil isolate, pseudomonad hw, converted thiosulfate to tetrathionate during growth on acetate. none of the organisms could use thiosulfate as sole energy source. the quantitative recovery of all the thiosulfate supplied to heterotrophic ... | 1988 | 24202996 |
| delignification and enhanced gas release from soil containing lignocellulose by treatment with bacterial lignin degraders. | the aim of the study was to isolate bacterial lignin-degrading bacteria from municipal solid waste soil, and to investigate whether they could be used to delignify lignocellulose-containing soil, and enhance methane release. | 2017 | 28393443 |
| controlling the regioselectivity of baeyer-villiger monooxygenases by mutation of active-site residues. | baeyer-villiger monooxygenase (bvmo)-mediated regiodivergent conversions of asymmetric ketones can lead to the formation of "normal" or "abnormal" lactones. in a previous study, we were able to change the regioselectivity of a bvmo by mutation of the active-site residues to smaller amino acids, which thus created more space. in this study, we demonstrate that this method can also be used for other bvmo/substrate combinations. we investigated the regioselectivity of 2-oxo-δ(3) -4,5,5-trimethylcyc ... | 2017 | 28504873 |
| suppression of enteric bacteria by bacteriophages: importance of phage polyvalence in the presence of soil bacteria. | bacteriophages are widely recognized for their importance in microbial ecology and bacterial control. however, little is known about how phage polyvalence (i.e., broad host range) affects bacterial suppression and interspecies competition in environments harboring enteric pathogens and soil bacteria. here we compare the efficacy of polyvalent phage pef1 versus coliphage t4 in suppressing a model enteric bacterium (e. coli k-12) in mixtures with soil bacteria (pseudomonas putida f1 and bacillus s ... | 2017 | 28414441 |