| micromorphology of gram-negative hydrogen bacteria. i. cell morphology and flagellation. | the cell morphology, the arrangement and fine structure of flagella and the piliation of the following gram-negative aerobic hydrogen bacteria have been studied: alcaligenes eutrophus, alcaligenes paradoxus, alcaligenes ruhlandii, pseudomonas flava, pseudomonas pseudoflava, pseudomonas palleronii, pseudomonas facilis, aquaspirillum autotrophicum, paracoccus denitrificans, corynebacterium autotrophicum, and strains ma 2 and sa 35. the identity of the bacteria was examined by their substrate spect ... | 1977 | 410385 |
| isolation and characterization of the pesticide-degrading plasmid pjp1 from alcaligenes paradoxus. | a strain of alcaligenes paradoxus, unable to degrade phenoxyacetic acid, was shown to degrade two synthetic derivatives of this molecule, the herbicides 2,4-dichlorophenoxyacetic acid and 2-methyl-4-chlorophenoxyacetic acid. the ability to degrade these pesticides is encoded by a 58-megadalton conjugal plasmid, pjp1. | 1978 | 690076 |
| [hydrogen and carboxide bacteria belonging to the microflora of degradation]. | the following bacteria oxidizing hydrogen and/or carbon monoxide were shown by cultivating in the concentration gradient of acetate, lactate, and glucose, to belong to the microflora of dispersal: hydrogenomonas eutropha z-1, h. pantotropha z-11, pseudomonas carboxydoflava z-1107, achromobacter carboxydus z-1171, paracoccus denitrificans, and alcaligenes paradoxus. | 1976 | 820943 |
| localization and stability of hydrogenases from aerobic hydrogen bacteria. | alcaligenes eutrophus strains h 16, b 19, g 27 and n9a contained two different hydrogenases. one enzyme catalyzed the reduction of nad by hydrogen and was strictly localized in the soluble cell fraction. while the second enzyme was found to be particulate and unable to react with nad. all other tested strains, alcaligenes paradoxus sa 29, pseudomonas facilis, p. palleronii rh 2, pseudomonas sp. strain ga 3, paracoccus denitrificans, aquaspirillum autotrophicum sa 32, and corynebacterium autotrop ... | 1977 | 871226 |
| [the autoselection of neustonic forms of bacteria]. | self-breeding of neuston forms of methylobacterium sp., pseudomonas putida bc-2, alcaligenes paradoxus bc-1, bacillus thuringiensis var. israilensis bacteria as well as of a mixed culture of methylotrophs is shown possible. in spite of ability of hydrophobicity of the cell surface the suggested method of self-breeding may be used to perfect properties of larvicidal biopreparations, and bacterial preparations which intensify self-purification of water bodies. | 1991 | 1791780 |
| properties of six pesticide degradation plasmids isolated from alcaligenes paradoxus and alcaligenes eutrophus. | biophysical and genetic properties of six independently isolated plasmids encoding the degradation of the herbicides 2,4-dichlorophenoxyacetic acid and 4-chloro-2-methylphenoxyacetic acid are described. four of the plasmids, pjp3, pjp4, pjp5, and pjp7, had molecular masses of 51 megadaltons, belonged to the incp1 incompatibility group, and transferred freely to strains of escherichia coli, rhodopseudomonas sphaeroides, rhizobium sp., agrobacterium tumefaciens, pseudomonas putida, pseudomonas flu ... | 1981 | 6257648 |
| influence of different chemical treatments on transport of alcaligenes paradoxus in porous media. | seven chemicals, three buffers, and a salt solution known to affect bacterial attachment were tested to quantify their abilities to enhance the penetration of alcaligenes paradoxus in porous media. chemical treatments included tween 20 (a nonionic surfactant that affects hydrophobic interactions), sodium dodecyl sulfate (an anionic surfactant), edta (a cell membrane permeabilizer that removes outer membrane lipopolysaccharides), sodium ppi (a surface charge modifier), sodium periodate (an oxidiz ... | 1995 | 7646012 |
| secretion of human epidermal growth factor (egf) in autotrophic culture by a recombinant hydrogen-utilizing bacterium, pseudomonas pseudoflava, carrying broad-host-range egf secretion vector pksegf2. | we constructed the broad-host-range human epidermal growth factor (egf) secretion plasmid pksegf2 by inserting the escherichia coli tac promoter, the signal sequence of pseudomonas stutzeri amylase, and the synthesized egf gene into the broad-host-range vector pkt230. e. coli jm109 carrying pksegf2 secreted egf into the periplasm and the culture medium under the control of the tac promoter. pseudomonas aeruginosa pao1161 carrying pksegf2 and pseudomonas putida ac10 carrying pksegf2 secreted egf ... | 1994 | 7944366 |
| frequency of horizontal gene transfer of a large catabolic plasmid (pjp4) in soil. | limited work has been done to assess the bioremediation potential of transfer of plasmid-borne degradative genes from introduced to indigenous organisms in the environment. here we demonstrate the transfer by conjugation of the catabolic plasmid pjp4, using a model system with donor and recipient organisms. the donor organism was alcaligenes eutrophus jmp134 and the recipient organism was variovorax paradoxus isolated from a toxic waste site. plasmid pjp4 contains genes for mercury resistance an ... | 1994 | 7993092 |
| integration and excision of a 2,4-dichlorophenoxyacetic acid-degradative plasmid in alcaligenes paradoxus and evidence of its natural intergeneric transfer. | a self-transmissible 2,4-dichlorophenoxyacetic acid (2,4-d)-degradative plasmid, pka2, has been identified in a new 2,4-d-degrading strain, alcaligenes paradoxus 2811p, isolated from agricultural soil. pka2 occurred as a 42.9-kb plasmid in strain 2811p. a derivative strain, 2811c, was isolated from a stock culture in which the entire pka2 plasmid was apparently integrated into the host chromosome without loss of the 2,4-d+ phenotype. this interpretation is based on the disappearance of a free pl ... | 1994 | 8071203 |
| degradation of homovanillate by a strain of variovorax paradoxus via ring hydroxylation. | a newly isolated strain of variovorax paradoxus could grow on homovanillate and several monohydroxylated phenylacetic acids. during growth on homovanillate, the organism formed separate nad(p)h-dependent hydroxylases with activity towards 4-hydroxyphenylacetic acid and homovanillate. homovanillate hydroxylase catalysed a typical monooxygenase reaction and had little activity towards 4-hydroxyphenylacetic acid gc-ms and tlc analysis suggested that homovanillate was 1-hydroxylated to yield a dihyd ... | 1995 | 8586270 |
| polaromonas vacuolata gen. nov., sp. nov., a psychrophilic, marine, gas vacuolate bacterium from antarctica. | several strains of a novel heterotrophic gas vacuolate bacterium were isolated from antarctic marine waters. the results of phylogenetic analyses in which 16s ribosomal dan sequencing was used, coupled with phenotypic tests, indicated that strain 34-p(t) (t = type strain) belongs to a new genus and species of the beta subgroup of the proteobacteria, for which the name polaromonas vacuolata is proposed. although the other four strains studied probably belong to this new species, dna-dna hybridiza ... | 1996 | 8782696 |
| microbial communities associated with anaerobic benzene degradation in a petroleum-contaminated aquifer. | microbial community composition associated with benzene oxidation under in situ fe(iii)-reducing conditions in a petroleum-contaminated aquifer located in bemidji, minn., was investigated. community structure associated with benzene degradation was compared to sediment communities that did not anaerobically oxidize benzene which were obtained from two adjacent fe(iii)-reducing sites and from methanogenic and uncontaminated zones. denaturing gradient gel electrophoresis of 16s rdna sequences ampl ... | 1999 | 10388703 |
| calorimetrically recognized maximum yield of poly-3-hydroxybutyrate (phb) continuously synthesized from toxic substrates. | the broader usage of poly-beta-hydroxybutyrate (phb), for instance as bulk plastics, calls for cheap raw materials and greater overall process efficiency. the bacterial synthesis is generally induced and promoted by the limitation of growth via nitrogen, oxygen or phosphate depletion with the simultaneous excess and higher concentration of the carbon substrate. consequently, toxic substrates have been considered unsuitable for phb synthesis. nevertheless, a single-stage continuous process for pr ... | 2000 | 10682283 |
| metabolism of acyl-homoserine lactone quorum-sensing signals by variovorax paradoxus. | acyl-homoserine lactones (acyl-hsls) serve as dedicated cell-to-cell signaling molecules in many species of the class proteobacteria. we have addressed the question of whether these compounds can be degraded biologically. a motile, rod-shaped bacterium was isolated from soil based upon its ability to utilize n-(3-oxohexanoyl)-l-homoserine lactone as the sole source of energy and nitrogen. the bacterium was classified as a strain of variovorax paradoxus. the v. paradoxus isolate was capable of gr ... | 2000 | 11092851 |
| a calorimetrically based method to convert toxic compounds into poly-3-hydroxybutyrate and to determine the efficiency and velocity of conversion. | a fed-batch method for converting toxic substrates into poly-3-hydroxybutyrate is presented. the method involves a series of batch-growth processes, regulated by adding small amounts of carbon substrate, during the course of which the concentration of the nitrogen source decreases and controls the distribution of the substrate-carbon assimilated. the addition of carbon substrate is controlled, and the small changes that occur in the growth pattern are interpreted using high-resolution reaction c ... | 2001 | 11330720 |
| characterization of (r/s)-mecoprop [2-(2-methyl-4-chlorophenoxy) propionic acid]-degrading alcaligenes sp.cs1 and ralstonia sp. cs2 isolated from agricultural soils. | the herbicide mecoprop [2-(2-methyl-4-chlorophenoxy) propionic acid] is widely applied to corn fields in order to control broad-leaved weeds. however, it is often detected in groundwater where it can be a persistent contaminant. two mecoprop-degrading bacterial strains were isolated from agricultural soils through their capability to degrade (r/s)-mecoprop rapidly. 16s rdna sequencing of the isolates demonstrated that one was closely related to the genera alcaligenes sp. (designated cs1) and the ... | 2001 | 11359515 |
| characterization of plant growth promoting rhizobacteria isolated from polluted soils and containing 1-aminocyclopropane-1-carboxylate deaminase. | fifteen bacterial strains containing 1-aminocyclopropane-1-carboxylate (acc) deaminase were isolated from the rhizoplane of pea (pisum sativum l.) and indian mustard (brassica juncea l.) grown in different soils and a long-standing sewage sludge contaminated with heavy metals. the isolated strains were characterized and assigned to various genera and species, such as pseudomonas brassicacearum, pseudomonas marginalis, pseudomonas oryzihabitans, pseudomonas putida, pseudomonas sp., alcaligenes xy ... | 2001 | 11547884 |
| isolation and characterization of acetate-utilizing anaerobes from a freshwater sediment. | acetate-degrading anaerobic microorganisms in freshwater sediment were quantified by the most probable number technique. from the highest dilutions a methanogenic, a sulfate-reducing, and a nitrate-reducing microorganism were isolated with acetate as substrate. the methanogen (culture ampb-zg) was non-motile and rod-shaped with blunted ends (0.5-1 mm x 3-4 mm long). doubling times with acetate at 30-35 degrees c were 5.6-8.1 days. the methanogen grew only on acetate. analysis of the 16s rrna seq ... | 2000 | 12035087 |
| a chlorophyll a fluorescence-based lemna minor bioassay to monitor microbial degradation of nanomolar to micromolar concentrations of linuron. | a plant-microbial bioassay, based on the aquatic macrophyte lemna minor l. (duckweed), was used to monitor biodegradation of nano- and micromolar concentrations of the phenylurea herbicide linuron. after 7 days of exposure to linuron, log-logistic-based dose-response analysis revealed significant growth inhibition on the total frond area of l. minor when linuron concentrations > or = 80 nm were added to the bioassay. a plant-protective effect was obtained for all concentrations > 80 nm by inocul ... | 2002 | 12071978 |
| identification and characterization of a new gene from variovorax paradoxus iso1 encoding n-acyl-d-amino acid amidohydrolase responsible for d-amino acid production. | an n-acyl-d-amino acid amidohydrolase (n-d-aaase) was identified in cell extracts of a strain, iso1, isolated from an environment containing n-acetyl-d-methionine. the bacterium was classified as variovorax paradoxus by phylogenetic analysis. the gene was cloned and sequenced. the gene consisted of a 1467-bp orf encoding a polypeptide of 488 amino acids. the v. paradoxusn-d-aaase showed significant amino acid similarity to the n-acyl-d-amino acid amidohydrolases of the two eubacteria alcaligenes ... | 2002 | 12354118 |
| arthrobacter strain vai-a utilizes acyl-homoserine lactone inactivation products and stimulates quorum signal biodegradation by variovorax paradoxus. | many proteobacteria produce acyl-homoserine lactones (acyl-hsls) and employ them as dedicated cell-to-cell signals in a process known as quorum sensing. previously, variovorax paradoxus vai-c was shown to utilize diverse acyl-hsls as sole sources of energy and nitrogen. we describe here the properties of a second isolate, arthrobacter strain vai-a, obtained from the same enrichment culture that yielded v. paradoxus vai-c. although strain vai-a grew rapidly and exponentially on a number of substr ... | 2003 | 12571011 |
| microbial consortia that degrade 2,4-dnt by interspecies metabolism: isolation and characterisation. | two consortia, isolated by selective enrichment from a soil sample of a nitroaromatic-contaminated site, degraded 2,4-dnt as their sole nitrogen source without accumulating one or more detectable intermediates. though originating from the same sample, the optimised consortia had no common members, indicating that selective enrichment resulted in different end points. consortium 1 and consortium 2 contained four and six bacterial species respectively, but both had two members that were able to co ... | 2003 | 12801097 |
| bacterial populations associated with the oxidation and reduction of arsenic in an unsaturated soil. | microbial populations responsible for the oxidation and reduction of as were examined in unsaturated (aerobic) soil columns treated with 75 microm arsenite [as(iii)] or 250 microm arsenate [as(v)]. arsenite [as(iii)] was rapidly oxidized to as(v) via microbial activity, whereas no apparent reduction of as(v) was observed in the column experiments. eight aerobic heterotrophic bacteria with varying as redox phenotypes were isolated from the same columns. three isolates, identified as agrobacterium ... | 2004 | 14740724 |
| flow calorimetry and dielectric spectroscopy to control the bacterial conversion of toxic substrates into polyhydroxyalcanoates. | the microbial conversion of toxic substrates into valuable products in continuous culture requires the equivalent of a tight rope walk between formation of the desired product and intoxication of the microbial catalyst. the condition of the latter is reflected immediately by changes in heat flow rate and beta-dispersion in an electrical rf field. therefore, these were applied to the example of the continuous growth-associated synthesis of polyhydroxyalcanoates (pha) from phenol by the bacterial ... | 2004 | 14760695 |
| identification and characterization of a novel d-amidase gene from variovorax paradoxus and its expression in escherichia coli. | the gene for the newly described d-amidase from variovorax paradoxus (krieg et al. 2002) was cloned and functionally expressed in escherichia coli. since native enzyme was available in minute amounts only, we determined the n-terminal sequence of the enzyme and utilized the universal genomewalker approach to make use of the common internal sequence of the amidase signature family. the high gc content of the gene made it necessary to employ an appropriate dna polymerase in the amplification react ... | 2005 | 15480636 |
| seasonal change in bacterial flora and biomass in mountain snow from the tateyama mountains, japan, analyzed by 16s rrna gene sequencing and real-time pcr. | the bacterial flora and biomass in mountain snow from the tateyama mountains, toyama prefecture, japan, one of the heaviest snowfall regions in the world, were analyzed by amplified ribosomal dna restriction analysis followed by 16s rrna gene sequencing and dna quantification by real-time pcr. samples of surface snow collected in various months during the melting season contained a psychrophilic bacterium, cryobacterium psychrophilum, and two psychrotrophic bacteria, variovorax paradoxus and jan ... | 2005 | 15640179 |
| purification, characterization, gene cloning and nucleotide sequencing of d: -stereospecific amino acid amidase from soil bacterium: delftia acidovorans. | the d-amino acid amidase-producing bacterium was isolated from soil samples using an enrichment culture technique in medium broth containing d-phenylalanine amide as a sole source of nitrogen. the strain exhibiting the strongest activity was identified as delftia acidovorans strain 16. this strain produced intracellular d-amino acid amidase constitutively. the enzyme was purified about 380-fold to homogeneity and its molecular mass was estimated to be about 50 kda, on sodium dodecyl sulfate poly ... | 2005 | 15959727 |
| isolation and molecular detection of methylotrophic bacteria occurring in the human mouth. | diverse methylotrophic bacteria were isolated from the tongue, and supra- and subgingival plaque in the mouths of volunteers and patients with periodontitis. one-carbon compounds such as dimethylsulfide in the mouth are likely to be used as growth substrates for these organisms. methylotrophic strains of bacillus, brevibacterium casei, hyphomicrobium sulfonivorans, methylobacterium, micrococcus luteus and variovorax paradoxus were characterized physiologically and by their 16s rrna gene sequence ... | 2005 | 16011760 |
| extracellular dna in single- and multiple-species unsaturated biofilms. | the extracellular polymeric substances (eps) of bacterial biofilms form a hydrated barrier between cells and their external environment. better characterization of eps could be useful in understanding biofilm physiology. the eps are chemically complex, changing with both bacterial strain and culture conditions. previously, we reported that pseudomonas aeruginosa unsaturated biofilm eps contains large amounts of extracellular dna (edna) (r. e. steinberger, a. r. allen, h. g. hansma, and p. a. hol ... | 2005 | 16151131 |
| control of continuous polyhydroxybutyrate synthesis using calorimetry and flow cytometry. | the substrate-carbon flow can be controlled in continuous bioreactor cultures by the medium composition, for example, by the c/n ratio. the carbon distribution is optimal when a maximum fraction flows into the desired product and the residual is just sufficient to compensate for the dilution of the microbial catalyst. undershooting of the latter condition is reflected immediately by changes in the gibbs energy dissipation and cellular states. two calorimetric measurement principles were applied ... | 2006 | 16245347 |
| molecular characterization of the nonphotosynthetic partner bacterium in the consortium "chlorochromatium aggregatum". | phototrophic consortia represent valuable model systems for the study of signal transduction and coevolution between different bacteria. the phototrophic consortium "chlorochromatium aggregatum" consists of a colorless central rod-shaped bacterium surrounded by about 20 green-pigmented epibionts. although the epibiont was identified as a member of the green sulfur bacteria, and recently isolated and characterized in pure culture, the central colorless bacterium has been identified as a member of ... | 2005 | 16269785 |
| cooperative catabolic pathways within an atrazine-degrading enrichment culture isolated from soil. | atrazine degradation previously has been shown to be carried out by individual bacterial species or by relatively simple consortia that have been isolated using enrichment cultures. here, the degradative pathway for atrazine was examined for a complex 8-membered enrichment culture. the species composition of the culture was determined by pcr-dgge. the bacterial species included agrobacterium tumefaciens, caulobacter crescentus, pseudomonas putida, sphingomonas yaniokuyae, nocardia sp., rhizobium ... | 2005 | 16329946 |
| biodegradation of 3-nitrotyrosine by burkholderia sp. strain js165 and variovorax paradoxus js171. | the cascade of reactive nitrogen species generated from nitric oxide causes modification of proteins, lipids, and nucleic acids in a wide range of organisms. 3-nitrotyrosine is one of the most common products of the action of reactive nitrogen species on proteins. although a great deal is known about the formation of 3-nitrotyrosine, the subsequent metabolism of this compound is a mystery. variovorax paradoxus js171 and burkholderia sp. strain js165 were isolated from soil slurries when 3-nitrot ... | 2006 | 16461647 |
| variovorax dokdonensis sp. nov., isolated from soil. | a gram-negative, motile and oval- or rod-shaped bacterial strain, ds-43t, was isolated from soil from dokdo, korea, and its taxonomic position was investigated by using a polyphasic approach. the strain grew optimally at ph 7.0-8.0 and at 30 degrees c in the presence of 0.5 % (w/v) nacl. strain ds-43t had q-8 as the predominant ubiquinone and c(16 : 0), c(16 : 1)omega7c and/or iso-c(15 : 0) 2-oh, c(18 : 1)omega7c and c(17 : 0) cyclo as the major fatty acids, which are consistent with the corresp ... | 2006 | 16585700 |
| arsenic-resistant proteobacterium from the phyllosphere of arsenic-hyperaccumulating fern (pteris vittata l.) reduces arsenate to arsenite. | an arsenic-resistant bacterium, asrb1, was isolated from the fronds of pteris vittata grown in a site contaminated with copper chromium arsenate. the bacterium exhibited resistance to arsenate, arsenite, and antimony in the culture medium. asrb1, like pseudomonas putida, grew on macconkey and xylose-lactose-desoxycholate agars and utilized citrate but, unlike p. putida, was positive for indole test and negative for oxidase test. a phylogenetic analysis of the 16s rrna gene showed that asrb1 is a ... | 2006 | 16917527 |
| degradability of dimethyl terephthalate by variovorax paradoxus t4 and sphingomonas yanoikuyae dos01 isolated from deep-ocean sediments. | two strains of bacteria were isolated from deep-ocean sediments of the south china sea using enrichment culturing technique and they were identified as sphingomonas yanoikuyae dos01 (ay878409) and variovorax paradoxus t4 (ay878410) based on 16s rrna gene sequences. s. yanoikuyae dos01 was only capable of transforming dimethyl terephthalate (dmtp) to monomethyl terephthalate (mmtp) without further degradation while v. paradoxus t4 exhibited ability in mineralizing dmtp as the sole source of carbo ... | 2006 | 16955363 |
| biodegradation of methyl tert-butyl ether by cold-adapted mixed and pure bacterial cultures. | an aerobic mixed bacterial culture (cl-emc-1) capable of utilizing methyl tert-butyl ether (mtbe) as the sole source of carbon and energy with a growth temperature range of 3 to 30 degrees c and optimum of 18 to 22 degrees c was enriched from activated sludge. transient accumulation of tert-butanol (tba) occurred during utilization of mtbe at temperatures from 3 degrees c to 14 degrees c, but tba did not accumulate above 18 degrees c. the culture utilized mtbe at a concentration of up to 1.5 g l ... | 2007 | 17146651 |
| variovorax soli sp. nov., isolated from greenhouse soil. | a gram-negative, rod-shaped, non-spore-forming bacterium, strain gh9-3(t), isolated from greenhouse soil, was investigated in a polyphasic study. the novel organism grew at 10-35 degrees c, 0-3 % nacl and ph 5-9. it had ubiquinone 8 (q-8) as the predominant isoprenoid quinone and possessed c(16 : 0), summed feature 3, c(17 : 0) cyclo and c(18 : 1) omega7c as the major fatty acids (together representing 87.4 % of the total). the dna g+c content was 67.1 mol%. 16s rrna gene sequence analysis of st ... | 2006 | 17158995 |
| isolation and characterization of hydrogen-oxidizing bacteria induced following exposure of soil to hydrogen gas and their impact on plant growth. | in many legumes, the nitrogen fixing root nodules produce h2 gas that diffuses into soil. it has been demonstrated that such exposure of soil to h2 can promote plant growth. to assess whether this may be due to h2-oxidizing microorganisms, bacteria were isolated from soil treated with h2 under laboratory conditions and from soils collected adjacent to h2 producing soybean nodules. nineteen isolates of h2-oxidizing bacteria were obtained and all exhibited a half-saturation coefficient (ks) for h2 ... | 2007 | 17222141 |
| desulfurization of aromatic sulfonates by rhizosphere bacteria: high diversity of the asfa gene. | the plant growth-promoting effect of pseudomonas putida s-313 is associated with its ability to desulfurize arylsulfonates. to understand this further, other plant-associated bacteria able to desulfurize a range of arylsulfonates were isolated from the rhizospheres of winter and spring barley. the isolates belonged to the beta-proteobacteria, including bacteria from the variovorax paradoxus group and from the acidovorax genus. they desulfurized toluenesulfonate to p-cresol, and were found to con ... | 2007 | 17222151 |
| identification of diazotrophs in the culturable bacterial community associated with roots of lasiurus sindicus, a perennial grass of thar desert, india. | lasiurus sindicus is a highly nutritive, drought-tolerant, perennial grass that is endemic to the thar desert of rajasthan, india. analysis of 16s rrna coding genes of the bacterial isolates enriched in nitrogen-free semisolid medium, from the surface-sterilized roots of l. sindicus, showed predominance of gram-negative over gram-positive bacteria. according to comparative sequence analysis of 16s rdna sequence data, gram-positive bacteria with low gc content (staphylococcus warneri and bacillus ... | 2007 | 17264993 |
| heavy metal resistance and genotypic analysis of metal resistance genes in gram-positive and gram-negative bacteria present in ni-rich serpentine soil and in the rhizosphere of alyssum murale. | forty-six bacterial cultures, including one culture collection strain, thirty from the rhizosphere of alyssum murale and fifteen from ni-rich soil, were tested for their ability to tolerate arsenate, cadmium, chromium, zinc, mercury, lead, cobalt, copper, and nickel in their growth medium. the resistance patterns, expressed as minimum inhibitory concentrations, for all cultures to the nine different metal ions were surveyed by using the agar dilution method. a large number of the cultures were r ... | 2007 | 17276484 |
| variovorax boronicumulans sp. nov., a boron-accumulating bacterium isolated from soil. | a non-spore-forming, gram-negative, motile, rod-shaped, boron-accumulating bacterium isolated from soil was characterized by polyphasic taxonomy. the strain, designated bam-48(t), was positive for catalase and oxidase activities and grew at 4-37 degrees c, 0-1% nacl and ph 5-9. comparative analysis of the 16s rrna gene sequence demonstrated that the novel isolate bam-48(t) was closely related to variovorax paradoxus iam 12373(t) (99.3% sequence similarity), variovorax soli gh9-3(t) (98.3%) and v ... | 2008 | 18175723 |
| characterization of biofilm formation on a humic material. | biofilms are major sites of carbon cycling in streams. therefore, it is crucial to improve knowledge about biofilms' structure and microbial composition to understand their contribution in the self-purification of surface water. the present work intends to study biofilm formation in the presence of humic substances (hss) as a carbon source. two biofilm flowcells were operated in parallel; one with synthetic stream water, displaying a background carbon concentration of 1.26+/-0.84 mg l(-1), the o ... | 2008 | 18712549 |
| gene cloning of alpha-methylserine aldolase from variovorax paradoxus and purification and characterization of the recombinant enzyme. | the alpha-methylserine aldolase gene from variovorax paradoxus strains aj110406, nbrc15149, and nbrc15150 was cloned and expressed in escherichia coli. formaldehyde release activity from alpha-methyl-l-serine was detected in the cell-free extract of e.coli expressing the gene from three strains. the recombinant enzyme from v. paradoxus nbrc15150 was purified. the vmax and km of the enzyme for the formaldehyde release reaction from alpha-methyl-l-serine were 1.89 micromol min(-1) mg(-1) and 1.2 m ... | 2008 | 18838814 |
| purification and gene cloning of alpha-methylserine aldolase from ralstonia sp. strain aj110405 and application of the enzyme in the synthesis of alpha-methyl-l-serine. | by screening microorganisms that are capable of assimilating alpha-methyl-dl-serine, we detected alpha-methylserine aldolase in ralstonia sp. strain aj110405, variovorax paradoxus aj110406, and bosea sp. strain aj110407. a homogeneous form of this enzyme was purified from ralstonia sp. strain aj110405, and the gene encoding the enzyme was cloned and expressed in escherichia coli. the enzyme appeared to be a homodimer consisting of identical subunits, and its molecular mass was found to be 47 kda ... | 2008 | 18952881 |
| 3-mercaptopropionate dioxygenase, a cysteine dioxygenase homologue, catalyzes the initial step of 3-mercaptopropionate catabolism in the 3,3-thiodipropionic acid-degrading bacterium variovorax paradoxus. | the thioether 3,3-thiodipropionic acid can be used as precursor substrate for biotechnological synthesis of 3-mercaptopropionic acid-containing polythioesters. therefore, the hitherto unknown catabolism of this compound was elucidated to engineer novel and improved polythioester biosynthesis pathways in the future. bacteria capable of using 3,3-thiodipropionic acid as the sole source of carbon and energy for growth were enriched from the environment. from eleven isolates, tbea3, tbea6, and sfwt ... | 2009 | 19001372 |
| rhizosphere bacteria containing 1-aminocyclopropane-1-carboxylate deaminase increase yield of plants grown in drying soil via both local and systemic hormone signalling. | decreased soil water availability can stimulate production of the plant hormone ethylene and inhibit plant growth. strategies aimed at decreasing stress ethylene evolution might attenuate its negative effects. an environmentally benign (nonchemical) method of modifying crop ethylene relations - soil inoculation with a natural root-associated bacterium variovorax paradoxus 5c-2 (containing the enzyme 1-aminocyclopropane-1-carboxylate (acc) deaminase that degrades the ethylene precursor acc), was ... | 2009 | 19121036 |
| coordinated surface activities in variovorax paradoxus eps. | variovorax paradoxus is an aerobic soil bacterium frequently associated with important biodegradative processes in nature. our group has cultivated a mucoid strain of variovorax paradoxus for study as a model of bacterial development and response to environmental conditions. colonies of this organism vary widely in appearance depending on agar plate type. | 2009 | 19523213 |
| variovorax ginsengisoli sp. nov., a denitrifying bacterium isolated from soil of a ginseng field. | a gram-negative, aerobic or facultatively anaerobic, non-spore-forming, motile, rod-shaped bacterium (strain gsoil 3165(t)) was isolated from soil of a ginseng field in pocheon, south korea. its taxonomic position was determined by using a polyphasic approach. on the basis of 16s rrna gene sequence analysis, strain gsoil 3165(t) was shown to belong to the family comamonadaceae, class betaproteobacteria, and was related most closely to the type strains of variovorax boronicumulans (98.9 % similar ... | 2010 | 19684323 |
| effects of compost addition and simulated solarisation on the fate of ralstonia solanacearum biovar 2 and indigenous bacteria in soil. | abstract the effects of compost addition and simulated solarisation of soil on the survival of ralstonia solanacearum biovar 2 strain 1609, as well as on the structure of indigenous soil bacterial communities, were analysed. in addition, effects on the invasion of susceptible test plants by strain 1609 were assessed. in untreated soil in microcosms and the field, strain 1609 showed slow progressive declines, from 10(6)-10(7) to roughly 10(4)-10(5) cfu per g dry soil in around 60 days. when these ... | 2003 | 19719697 |
| the rhizosphere bacterium variovorax paradoxus 5c-2 containing acc deaminase does not increase systemic aba signaling in maize (zea mays l.). | | 2009 | 19816130 |
| saccamoeba lacustris, sp. nov. (amoebozoa: lobosea: hartmannellidae), a new lobose amoeba, parasitized by the novel chlamydia 'candidatus metachlamydia lacustris' (chlamydiae: parachlamydiaceae). | an amoeba isolated from an aquatic biotope, identified morphologically as saccamoeba limax, was found harbouring mutualistic rod-shaped gram-negative bacteria. during their cultivation on agar plates, a coinfection also by lysis-inducing chlamydia-like organisms was found in some subpopulations of that amoeba. .here we provide a molecular-based identification of both the amoeba host and the two bacterial endosymbionts. analysis of the 18s rrna gene revealed that this strain is the sister-group t ... | 2010 | 20347279 |
| effects of plant genotype and growth stage on the betaproteobacterial communities associated with different potato cultivars in two fields. | bacterial communities in the rhizosphere are dynamic and susceptible to changes in plant conditions. among the bacteria, the betaproteobacteria play key roles in nutrient cycling and plant growth promotion, and hence the dynamics of their community structures in the rhizosphere should be investigated. here, the effects of plant cultivar, growth stage, and soil type on the communities associated with potato cultivars aveka, aventra, karnico, modena, premiere, and désirée were assessed for two dif ... | 2010 | 20363788 |
| assessment of mtbe biodegradation pathways by two-dimensional isotope analysis in mixed bacterial consortia under different redox conditions. | the fuel oxygenate, methyl tert-butyl ether (mtbe), although now widely banned or substituted, remains a persistent groundwater contaminant. multidimensional compound-specific isotope analysis (csia) of carbon and hydrogen is being developed for determining the extent of mtbe loss due to biodegradation and can also potentially distinguish between different biodegradation pathways. carbon and hydrogen isotopic fractionation factors were determined for mtbe degradation in aerobic and anaerobic lab ... | 2010 | 20582586 |
| aerobic degradation of mercaptosuccinate by the gram-negative bacterium variovorax paradoxus strain b4. | the gram-negative bacterium variovorax paradoxus strain b4 was isolated from soil under mesophilic and aerobic conditions to elucidate the so far unknown catabolism of mercaptosuccinate (ms). during growth with ms this strain released significant amounts of sulfate into the medium. tn5::mob-induced mutagenesis was successfully employed and yielded nine independent mutants incapable of using ms as a carbon source. in six of these mutants, tn5::mob insertions were mapped in a putative gene encodin ... | 2010 | 21075928 |
| complete genome sequence of the metabolically versatile plant growth-promoting endophyte variovorax paradoxus s110. | variovorax paradoxus is a microorganism of special interest due to its diverse metabolic capabilities, including the biodegradation of both biogenic compounds and anthropogenic contaminants. v. paradoxus also engages in mutually beneficial interactions with both bacteria and plants. the complete genome sequence of v. paradoxus s110 is composed of 6,754,997 bp with 6,279 predicted protein-coding sequences within two circular chromosomes. genomic analysis has revealed multiple metabolic features f ... | 2010 | 21183664 |
| isolation and identification of soil bacteria growing at the expense of arbuscular mycorrhizal fungi. | soil-microorganism symbioses are of fundamental importance for plant adaptation to the environment. research in microbial ecology has revealed that some soil bacteria are associated with arbuscular mycorrhizal fungi (amf). however, these interactions may be much more complex than originally thought. to assess the type of bacteria associated with amf, we initially isolated spores of glomus irregulare from an agrostis stolonifera rhizosphere. the spores were washed with sterile water and plated on ... | 2011 | 21219415 |
| molecular definition of vaginal microbiota in east african commercial sex workers. | resistance to hiv infection in a cohort of commercial sex workers (csw) living in nairobi, kenya is linked to mucosal and anti-inflammatory factors that may be influenced by vaginal microbiota. since bacterial vaginosis (bv), a polymicrobial dysbiosis characterized by low levels of protective lactobacillus organisms, is an established risk factor for hiv infection, we investigated whether vaginal microbiology was associated with hiv-exposed seronegative (hesn) or hiv-seropositive (hiv+) status i ... | 2011 | 21531840 |
| variovorax defluvii sp. nov., isolated from sewage flowing into river geumho in south korea. | a polyphasic taxonomic study was carried out on 2c1-b(t) and 2c-21, two strains isolated from the sewage flowing into river geumho in korea.the cells of strains were gram-negative, non-spore-forming, motile and oval or rod-shaped bacteria. comparative 16s rrna gene sequence studies showed a clear affiliation of these two bacteria into the betaproteobacteria, which were most closely related to variovorax boronicumulans kctc 22010(t), variovorax dokdonensis kctc 12544(t), variovorax ginsengisoli k ... | 2011 | 21948092 |
| Bacterial communities in urban aerosols collected with wetted-wall cyclonic samplers and seasonal fluctuations of live and culturable airborne bacteria. | Airborne transmission of bacterial pathogens from point sources (e.g., ranches, dairy waste treatment facilities) to areas of food production (farms) has been suspected. Determining the incidence, transport and viability of extremely low levels of pathogens require collection of high volumes of air and characterization of live bacteria from aerosols. We monitored the numbers of culturable bacteria in urban aerosols on 21 separate days during a 9 month period using high volume cyclonic samplers a ... | 2011 | 22193549 |
| isolation of paenibacillus sp. and variovorax sp. strains from decaying woods and characterization of their potential for cellulose deconstruction. | prospection of cellulose-degrading bacteria in natural environments allows the identification of novel cellulases and hemicellulases that could be useful in second-generation bioethanol production. in this work, cellulolytic bacteria were isolated from decaying native forest soils by enrichment on cellulose as sole carbon source. there was a predominance of gram positive isolates that belonged to the phyla proteobacteria and firmicutes. many primary isolates with cellulolytic activity were not p ... | 2012 | 23301200 |
| multiple impacts of the plant growth-promoting rhizobacterium variovorax paradoxus 5c-2 on nutrient and aba relations of pisum sativum. | resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. to understand further how the 1-aminocyclopropane-1-carboxylate (acc) deaminase (accd)-containing rhizobacterium variovorax paradoxus 5c-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (aba) and aba metabolism were studied in pea (pisum sativum) plants following rhizosphere bacterial ... | 2012 | 23136167 |
| biochemical properties and crystal structure of a β-phenylalanine aminotransferase from variovorax paradoxus. | by selective enrichment, we isolated a bacterium that can use β-phenylalanine as a sole nitrogen source. it was identified by 16s rrna gene sequencing as a strain of variovorax paradoxus. enzyme assays revealed an aminotransferase activity. partial genome sequencing and screening of a cosmid dna library resulted in the identification of a 1,302-bp aminotransferase gene, which encodes a 46,416-da protein. the gene was cloned and overexpressed in escherichia coli. the recombinant enzyme was purifi ... | 2013 | 23087034 |
| genes that influence swarming motility and biofilm formation in variovorax paradoxus eps. | variovorax paradoxus is an aerobic soil bacterium associated with important biodegradative processes in nature. we use v. paradoxus eps to study multicellular behaviors on surfaces. | 2012 | 22363744 |
| microbiological oxidation of antimony(iii) with oxygen or nitrate by bacteria isolated from contaminated mine sediments. | bacterial oxidation of arsenite [as(iii)] is a well-studied and important biogeochemical pathway that directly influences the mobility and toxicity of arsenic in the environment. in contrast, little is known about microbiological oxidation of the chemically similar anion antimonite [sb(iii)]. in this study, two bacterial strains, designated idsbo-1 and idsbo-4, which grow on tartrate compounds and oxidize sb(iii) using either oxygen or nitrate, respectively, as a terminal electron acceptor, were ... | 2015 | 26431974 |
| the complete sequences and ecological roles of two incp-1β plasmids, phb44 and pbs64, isolated from the mycosphere of laccaria proxima. | two novel plasmids, coined phb44 and pbs64, were recently found in variovorax paradoxus strains hb44 and bs64 isolated from the mycosphere of laccaria proxima, on two different sampling occasions. we here describe the full sequences of phb44 and pbs64 and establish their evolutionary placement and ecological function. both plasmids, unique for mycospheric v. paradoxus, were around 58 kb in size. they possessed, in a very similar fashion, three main plasmid backbone regions, which were predicted ... | 2016 | 27445994 |
| identification of 3-sulfinopropionyl coenzyme a (coa) desulfinases within the acyl-coa dehydrogenase superfamily. | in a previous study, the essential role of 3-sulfinopropionyl coenzyme a (3sp-coa) desulfinase acyl-coa dehydrogenase (acd) in advenella mimigardefordensis strain dpn7(t) (acddpn7) during degradation of 3,3'-dithiodipropionic acid (dtdp) was elucidated. dtdp is a sulfur-containing precursor substrate for biosynthesis of polythioesters (ptes). acddpn7 showed high amino acid sequence similarity to acyl-coa dehydrogenases but was unable to catalyze a dehydrogenation reaction. hence, it was investig ... | 2014 | 24317404 |
| mercaptosuccinate dioxygenase, a cysteine dioxygenase homologue, from variovorax paradoxus strain b4 is the key enzyme of mercaptosuccinate degradation. | the versatile thiol mercaptosuccinate has a wide range of applications, e.g. in quantum dot research or in bioimaging. its metabolism is investigated in variovorax paradoxus strain b4, which can utilize this compound as the sole source of carbon and sulfur. proteomic studies of strain b4 resulted in the identification of a putative mercaptosuccinate dioxygenase, a cysteine dioxygenase homologue, possibly representing the key enzyme in the degradation of mercaptosuccinate. therefore, the putative ... | 2014 | 25228698 |
| bacterial communities associated with different anthurium andraeanum l. plant tissues. | plant-associated microbes have specific beneficial functions and are considered key drivers for plant health. the bacterial community structure of healthy anthurium andraeanum l. plants was studied by 16s rrna gene pyrosequencing associated with different plant parts and the rhizosphere. a limited number of bacterial taxa, i.e., sinorhizobium, fimbriimonadales, and gammaproteobacteria htcc2089 were enriched in the a. andraeanum rhizosphere. endophytes were more diverse in the roots than in the s ... | 2016 | 27524305 |
| the "gln-type" thiol dioxygenase from azotobacter vinelandii is a 3-mercaptopropionic acid dioxygenase. | cysteine dioxygenase (cdo) is a non-heme iron enzyme that catalyzes the o2-dependent oxidation of l-cysteine to produce cysteinesulfinic acid. bacterial cdos have been subdivided as either "arg-type" or "gln-type" on the basis of the identity of conserved active site residues. to date, "gln-type" enzymes remain largely uncharacterized. it was recently noted that the "gln-type" enzymes are more homologous with another thiol dioxygenase [3-mercaptopropionate dioxygenase (mdo)] identified in variov ... | 2015 | 26624219 |
| the rhizobacterium variovorax paradoxus 5c-2, containing acc deaminase, promotes growth and development of arabidopsis thaliana via an ethylene-dependent pathway. | many plant-growth-promoting rhizobacteria (pgpr) associated with plant roots contain the enzyme 1-aminocyclopropane-1-carboxylate (acc) deaminase and can metabolize acc, the immediate precursor of the plant hormone ethylene, thereby decreasing plant ethylene production and increasing plant growth. however, relatively few studies have explicitly linked ethylene emission and/or action to growth promotion in these plant-microbe interactions. this study examined effects of the pgpr variovorax parado ... | 2013 | 23404897 |
| microbial diversity and dynamics during the production of may bryndza cheese. | diversity and dynamics of microbial cultures were studied during the production of may bryndza cheese, a traditional slovak cheese produced from unpasteurized ewes' milk. quantitative culture-based data were obtained for lactobacilli, lactococci, total mesophilic aerobic counts, coliforms, e. coli, staphylococci, coagulase-positive staphylococci, yeasts, fungi and geotrichum spp. in ewes' milk, curd produced from it and ripened for 0 - 10 days, and in bryndza cheese produced from the curd, in th ... | 2014 | 24291178 |
| isolation of endophytic plant growth-promoting bacteria associated with the halophyte salicornia europaea and evaluation of their promoting activity under salt stress. | several reports have highlighted that many plant growth-promoting endophytic bacteria (pgpe) can assist their host plants in coping with various biotic and abiotic stresses. however, information about the pgpe colonizing in the halophytes is still scarce. this study was designed to isolate and characterize pgpe from salt-accumulating halophyte salicornia europaea grown under extreme salinity and to evaluate in vitro the bacterial mechanisms related to plant growth promotion. a total of 105 isola ... | 2016 | 27447799 |
| removal of methyl acrylate by ceramic-packed biotrickling filter and their response to bacterial community. | methyl acrylate is a widely used raw chemical materials and it is toxic in humans. in order to treat the methyl acrylate waste gas, a 3-layer btf packed with ceramic particles and immobilized with activated sludge was set up. the btf exhibited excellent removal efficiency that no methyl acrylate could be detected when ebrt was larger than 266s and inlet concentration was lower than 0.19g/m(3). the 1st layer performed the best at fixed inlet concentration of 0.42g/m(3). pcr combined with dgge was ... | 2016 | 26970927 |
| relationship between in vitro characterization and comparative efficacy of plant growth-promoting rhizobacteria for improving cucumber salt tolerance. | phosphate solubilization, 1-aminocyclopropane-1-carboxylic acid (acc)-deaminase activity and production of siderophores and indole acetic acid (iaa) are well-known traits of plant growth-promoting rhizobacteria (pgpr). here we investigated the expression of these traits as affected by salinity for three pgpr strains (pseudomonas fluorescens, bacillus megaterium and variovorax paradoxus) at two salinity levels [2 and 5 % nacl (w/v)]. among the three strains, growth of b. megaterium was the least ... | 2016 | 26860842 |
| poplar clones of different sizes, grown on a heavy metal polluted site, are associated with microbial populations of varying composition. | we performed a field trial to evaluate the response of different poplar clones to heavy metals. we found that poplar plants of the same clone, propagated by cuttings, had a marked variability of survival and growth in different zones of the field that were characterized by very similar physical-chemical prosperities. since metal uptake and its accumulation by plants can be affected by soil microorganisms, we investigated soil microbial populations that were collected in proximity to the roots of ... | 2012 | 22475220 |
| culturable endophytic bacterial communities associated with field-grown soybean. | assess the diversity of the culturable endophytic bacterial population associated with transgenic and nontransgenic soybean grown in field trial sites in brazil and characterize them phenotypically and genotypically focusing on characteristics related to plant growth promotion. | 2016 | 26744016 |
| incp-1β plasmids are important carriers of fitness traits for variovorax species in the mycosphere--two novel plasmids, phb44 and pbs64, with differential effects unveiled. | the laccaria proxima mycosphere strongly selects variovorax paradoxus cells. fifteen independent v. paradoxus strains, isolated from mycospheres sampled at two occasions, were investigated with respect to the occurrence of plasmids of sizes <60-100 kb. two v. paradoxus strains, hb44 and bs64, were found to contain such plasmids, which were coined phb44 and pbs64. replicon typing using a suite of plasmid-specific pcr systems indicated that both plasmids belong to the incp-1β group. also, both wer ... | 2015 | 25542203 |
| succinyl-coa:3-sulfinopropionate coa-transferase from variovorax paradoxus strain tbea6, a novel member of the class iii coenzyme a (coa)-transferase family. | the act gene of variovorax paradoxus tbea6 encodes a succinyl-coa:3-sulfinopropionate coenzyme a (coa)-transferase, act(tbea6) (2.8.3.x), which catalyzes the activation of 3-sulfinopropionate (3sp), an intermediate during 3,3'-thiodipropionate (tdp) degradation. in a previous study, accumulation of 3sp was observed in a tn5::mob-induced mutant defective in growth on tdp. in contrast to the wild type and all other obtained mutants, this mutant showed no growth when 3sp was applied as the sole sou ... | 2013 | 23772073 |
| inhibition of mushroom formation and induction of glycerol release-ecological strategies of burkholderia terrae bs001 to create a hospitable niche at the fungus lyophyllum sp. strain karsten. | we investigated the ecological strategies exerted by the soil bacterium burkholderia terrae bs001 at the hyphae of the soil saprotrophic fungus lyophyllum sp. strain karsten. recently, this bacterium has been reported to form biofilms around, and to comigrate with, growing hyphae of lyophyllum sp. strain karsten. in addition, it was found to be able to utilize fungal metabolites. here, we extend this work to shed some light on the interactions between the bacterial and fungal partner which allow ... | 2013 | 22915155 |
| sesquiterpenes from the conifer root rot pathogen heterobasidion occidentale. | investigation of the production of secondary metabolites of heterobasidion occidentale led to the isolation and identification of six sesquiterpenes (illudolone a and b, illudolactone a and b, deoxyfomannosin a and b) along with the well-known sesquiterpene fomannosin and the previously described benzohydrofuran fomannoxin. the structures and relative configurations of the compounds were determined by 1d and 2d nmr spectroscopic analysis as well as by hrms. their absolute configuration and biosy ... | 2012 | 22831894 |
| proteomic analysis of organic sulfur compound utilisation in advenella mimigardefordensis strain dpn7t. | 2-mercaptosuccinate (ms) and 3,3´-ditiodipropionate (dtdp) were discussed as precursor substance for production of polythioesters (pte). therefore, degradation of ms and dtdp was investigated in advenella mimigardefordensis strain dpn7t, applying differential proteomic analysis, gene deletion and enzyme assays. protein extracts of cells cultivated with ms, dtdp or 3-sulfinopropionic acid (sp) were compared with those cultivated with propionate (p) and/or succinate (s). the chaperone dnak (ratio ... | 2017 | 28358882 |
| the 46 kda dimeric protein from variovorax paradoxus shows faster methotrexate degrading activity in its nanoform compare to the native enzyme. | methotrexate degrading enzymes are required to overcome the toxicity of the methotrexate while treating the cancer. the enzyme from variovorax paradoxus converts the methotrexate in to non toxic products. methotrexate degrading enzyme from v. paradoxus is a dimeric protein with a molecular mass of 46 kda and it acts on casein and gelatin. this enzyme is optimally active at ph 7.5 and 40°c and nanoparticles of this enzyme were prepared by desolvation-crosslinking method. enzyme nanoparticles coul ... | 2016 | 26920479 |
| effect of the incp-1β plasmid phb44 on the population dynamics of burkholderia terrae bs001 in the lyophyllum sp. strain karsten mycosphere under different iron conditions. | burkholderia terrae strain bs001 is a well-described inhabitant of the mycosphere of diverse fungi. in the interaction between this bacterium and its fungal host in soil, competition for iron might be a key process. here, we address the capacity of the broad-host-range incp-1β plasmid phb44, originally isolated in variovorax paradoxus hb44, to enhance or modulate the competitiveness of b. terrae bs001 under different soil iron levels when confronted with (young versus ageing) mycelia of lyophyll ... | 2016 | 26705573 |
| aryl polyenes, a highly abundant class of bacterial natural products, are functionally related to antioxidative carotenoids. | bacterial pigments of the aryl polyene type are structurally similar to the well-known carotenoids with respect to their polyene systems. their biosynthetic gene cluster is widespread in taxonomically distant bacteria, and four classes of such pigments have been found. here we report the structure elucidation of the aryl polyene/dialkylresorcinol hybrid pigments of variovorax paradoxus b4 by hplc-uv-ms, maldi-ms and nmr. furthermore, we show for the first time that this pigment class protects th ... | 2016 | 26629877 |
| bacterial community structure shifted by geosmin in granular activated carbon system of water treatment plants. | we investigated the relation between the presence of geosmin in water and the bacterial community structure within the granular activated carbon (gac) system of water treatment plants in south korea. gac samples were collected in may and august of 2014 at three water treatment plants (sungnam, koyang, and yeoncho in korea). dissolved organic carbon and geosmin were analyzed before and after gac treatment. geosmin was found in raw water from sungnam and koyang water treatment plants but not in th ... | 2016 | 26437945 |
| variovorax gossypii sp. nov., isolated from gossypium hirsutum. | a beige-pigmented bacterial strain (jm-310t), isolated from the healthy internal root tissue of 4-week-old cotton (gossypium hirsutum, cultivar 'des-119') in tallassee (macon county), alabama, usa, was studied taxonomically. the isolate produced small rod-shaped cells, which showed a gram-negative staining behaviour. a comparison of the 16s rrna gene sequence of the isolate revealed 99.2, 98.8, 98.7, 98.7, 98.1 and 97.6 % similarity to the 16s rrna gene sequences of the type strains of variovora ... | 2015 | 26341669 |
| the genome of variovorax paradoxus strain tbea6 provides new understandings for the catabolism of 3,3'-thiodipropionic acid and hence the production of polythioesters. | the betaproteobacterium variovorax paradoxus strain tbea6 is capable of using 3,3'-thiodipropionic acid (tdp) as sole carbon and energy source for growth. this thioether is employed for several industrial applications. it can be applied as precursor for the biotechnical production of polythioesters (pte), which represent persistent bioplastics. consequently, the genome of v. paradoxus strain tbea6 was sequenced. the draft genome sequence comprises approximately 7.2mbp and 6852 predicted open rea ... | 2015 | 26073999 |
| variovorax guangxiensis sp. nov., an aerobic, 1-aminocyclopropane-1-carboxylate deaminase producing bacterium isolated from banana rhizosphere. | a 1-aminocyclopropane-1-carboxylate deaminase producing bacterium, designated gxgd002(t), was isolated from the rhizosphere of banana plants cultivated in guangxi province, china. phylogenetic analysis based on 16s rrna gene sequences revealed that strain gxgd002(t) is a member of the genus variovorax. high levels of 16s rrna gene sequence similarity are found between strain gxgd002(t) and variovorax paradoxus dsm 30034(t) (99.4 %), variovorax ginsengisoli kctc 12583(t) (99.1 %), variovorax boro ... | 2015 | 25504533 |
| p-cresol mineralization and bacterial population dynamics in a nitrifying sequential batch reactor. | the ability of a nitrifying sludge to oxidize p-cresol was evaluated in a sequential batch reactor (sbr). p-cresol was first transformed to p-hydroxybenzaldehyde and p-hydroxybenzoate, which were later mineralized. the specific rates of p-cresol consumption increased throughout the cycles. the bacterial population dynamics were monitored by using denaturing gradient gel electrophoresis (dgge) and sequencing of dgge fragments. the ability of the sludge to consume p-cresol and intermediates might ... | 2014 | 25193839 |
| mercaptosuccinate metabolism in variovorax paradoxus strain b4--a proteomic approach. | variovorax paradoxus b4 was isolated due to its ability to degrade the organic thiol compound mercaptosuccinate, which could be a promising precursor for novel polythioesters. the analysis of the proteome of this gram-negative bacterium revealed several proteins with significantly increased expression during growth of cells with mercaptosuccinate as carbon source when compared to cells grown with gluconate or succinate. among those, a large number of proteins involved in amino acid metabolism we ... | 2014 | 24839213 |
| genome-guided insights into the versatile metabolic capabilities of the mercaptosuccinate-utilizing β-proteobacterium variovorax paradoxus strain b4. | variovorax paradoxus b4 is able to utilize 2-mercaptosuccinate (ms) as sole carbon, sulfur and energy source. the whole genome of v. paradoxus b4 was sequenced, annotated and evaluated with special focus on genomic elements related to ms metabolism. the genome encodes two chromosomes harbouring 5 795 261 and 1 353 255 bp. a total of 6753 putative protein-coding sequences were identified. based on the genome and in combination with results from previous studies, a putative pathway for the degrada ... | 2014 | 24245581 |
| genome of the root-associated plant growth-promoting bacterium variovorax paradoxus strain eps. | variovorax paradoxus is a ubiquitous betaproteobacterium involved in plant growth promotion, the degradation of xenobiotics, and quorum-quenching activity. the genome of v. paradoxus strain eps consists of a single circular chromosome of 6,550,056 bp, with a 66.48% g+c content. | 2013 | 24158554 |
| ethylene limits abscisic acid- or soil drying-induced stomatal closure in aged wheat leaves. | the mechanism of age-induced decreased stomatal sensitivity to abscisic acid (aba) and soil drying has been explored here. older, fully expanded leaves partly lost their ability to close stomata in response to foliar aba sprays, and soil drying which stimulated endogenous aba production, while young fully expanded leaves closed their stomata more fully. however, aba- or soil drying-induced stomatal closure of older leaves was partly restored by pretreating plants with 1-methylcyclopropene (1-mcp ... | 2013 | 23488478 |
| metabolic characteristics of the species variovorax paradoxus. | this review outlines information about the gram-negative, aerobic bacterium variovorax paradoxus. the genomes of these species have g+c contents of 66.5-69.4 mol%, and the cells form yellow colonies. some strains of v. paradoxus are facultative lithoautotrophic, others are chemoorganotrophic. many of them are associated with important catabolic processes including the degradation of toxic and/or complex chemical compounds. the degradation pathways or other skills related to the following compoun ... | 2013 | 23192768 |
| environmental fate, toxicity, characteristics and potential applications of novel bioemulsifiers produced by variovorax paradoxus 7bct5. | the aims of this work were the characterisation and the evaluation of potential environmental applications of the bioemulsifiers produced by variovorax paradoxus 7bct5. v. paradoxus 7bct5 produces a mixture of high molecular weight polysaccharides. the extracellular bioemulsifiers were able to produce a thick stable oil/water emulsion and maintained the emulsification activity after boiling and at low temperatures. environmental behavior and impact of bioemulsifiers release were assessed by eval ... | 2012 | 22277206 |