PMID(sorted descending)
microbial interactions within a cheese microbial community.the interactions that occur during the ripening of smear cheeses are not well understood. yeast-yeast interactions and yeast-bacterium interactions were investigated within a microbial community composed of three yeasts and six bacteria found in cheese. the growth dynamics of this community was precisely described during the ripening of a model cheese, and the lotka-volterra model was used to evaluate species interactions. subsequently, the effects on ecosystem functioning of yeast omissions in ...200817981942
d-serine dehydratase from chicken kidney: a vertebral homologue of the cryptic enzyme from burkholderia cepacia.d-serine dehydratase (dsd) catalyses the conversion of d-serine to pyruvate and ammonia. d-serine is a physiological modulator of glutamate neurotransmission in vertebrate brains. in mammals d-serine is degraded by d-amino-acid oxidase, whereas in chicken brain it is degraded by dsd, as we have recently demonstrated [tanaka et al. (2007) anal. biochem. 362, 83-88]. to clarify the roles of dsd in avian species, we purified dsd from chicken kidney. the purified enzyme was a heterodimer consisting ...200817977854
oligosaccharide profiles of the prostate specific antigen in free and complexed forms from the prostate cancer patient serum and in seminal plasma: a glycopeptide approach.the oligosaccharide structures of prostate specific antigen (psa) are expected to be useful in discriminating prostate cancer from benign conditions both accompanied by increased serum psa levels. a large proportion of psa forms a covalent complex with a glycoprotein, alpha(1)-antichymotrypsin, in human blood. in the present study, the glycan profiles of free and complexed forms of psa from cancer patient serum and of seminal plasma psa were compared by analyzing the glycopeptides obtained by ly ...200817956937
[phylogenetic diversity of culturable bacteria in the ancient salt deposits of the yipinglang salt mine, p. r. china].the microbial diversity of cultivable bacteria, isolated from the ancient salt deposits from the yipinglang salt mine (ypl) in the yunnan province, p. r. china,was investigated by using conventional culture-dependent method and phylogenetic analyses based on 16s rrna gene sequence comparisons. 38 bacteria strains were isolated from the brine, halite and saline soil samples on mba (marine broth agar 2216, difco) and isp 2 (international streotomyces project medium 2) media supplemented with 0.5-3 ...200717944352
enhancement of androstadienedione production from progesterone by biotransformation using the hydroxypropyl-beta-cyclodextrin complexation technique.the enhanced production of androstadienedione (add) from progesterone (p) using the hydroxypropyl-beta-cyclodextrin (hpbetacd) complexation technique by biotransformation was demonstrated. the microorganisms used were bacillus sphaericus atcc 245, b. sphaericus atcc 7063, b. sphaericus atcc 13805, arthrobacter simplex atcc 6946, b. sphaericus tistr 670 and those screened from soils in chiang mai province, thailand which were b. sphaericus srp i, b. sphaericus srp ii and b. sphaericus srp iii. th ...200817936614
viability, diversity and composition of the bacterial community in a high arctic permafrost soil from spitsbergen, northern norway.the viable and non-viable fractions of the bacterial community in a 2347-year-old permafrost soil from spitsbergen were subjected to a comprehensive investigation using culture-independent and culture-dependent methods. live/dead baclight staining revealed that 26% of the total number of bacterial cells were viable. quantitatively, aerobic microcolonies, aerobic colony-forming units and culturable anaerobic bacteria comprised a minor fraction of the total number of viable bacteria, which underli ...200717922769
degradation of mixtures of phenolic compounds by arthrobacter chlorophenolicus this study the chlorophenol-degrading actinobacterium, arthrobacter chlorophenolicus a6, was tested for its ability to grow on mixtures of phenolic compounds. during the experiments depletion of the compounds was monitored, as were cell growth and activity. activity assays were based on bioluminescence output from a luciferase-tagged strain. when the cells were grown on a mixture of 4-chlorophenol, 4-nitrophenol and phenol, 4-chlorophenol degradation apparently was delayed until 4-nitrophenol ...200817917705
arbuscular mycorrhizal fungi and rhizospheric bacteria diversity along an altitudinal gradient in south american puna grassland.rhizospheric soil samples were taken from puna native grasses along an altitudinal gradient. biodiversity of arbuscular mycorrhizal fungi (amf) and associated bacteria was analyzed considering altitude and grasses photosynthetic pathways (metabolic type c3, c4). cultivation-dependent approaches were applied to obtain further information about the phylogeny of the dominating cultivable aerobic-heterotrophic bacteria communities present in rhizospheric soil samples. in average, the bacterial count ...200817912580
phylogenetic diversity of bacteria isolates from the qinghai-tibet plateau permafrost region.the qinghai-tibet plateau in east asia is a unique and important permafrost environment. however, its microbiology remains largely unexplored to date. in this study, sediment samples were collected from the qinghai-tibet plateau permafrost region, bacteria isolation procedures were performed 8 times, and the samples incubated at 4 degrees c for nearly 3 months. the number of colony forming units (cfu) ranged from 0 to 10(7)/(g dry soil). the quantity of culturable bacteria grew exponentially wit ...200717898857
identification of bacteria from clinical samples using bartonella alpha-proteobacteria growth an effort to overcome historical problems associated with the isolation of bartonella species from animal and human blood samples, our laboratory developed a novel, chemically modified, insect-based, liquid culture medium (bartonella alpha-proteobacteria growth medium, bapgm). in this study, we describe the isolation of non-bartonella bacteria from aseptically obtained human blood and tissue samples that were inoculated into bapgm pre-enrichment culture medium, and were obtained during attemp ...200717889384
trans-stilbene degradation by arthrobacter sp. sl3 cells.trans-stilbene degradation was examined by the reaction using resting cells of microorganisms isolated through the enrichment culture using trans-stilbene. the strain sl3, showing the highest trans-stilbene-degrading activity, was identified as arthrobacter sp. one of the reaction products was identified to be cis,cis-muconic acid. arthrobacter sp. sl3 cells also transformed benzaldehyde, benzoic acid and catechol into cis,cis-muconic acid, suggesting that one benzene ring of trans-stilbene was ...200817885812
enzymatic synthesis of cephalosporins. the immobilized acylase from arthrobacter viscosus: a new useful biocatalyst.the acylase from arthrobacter viscosus was immobilized, studied in the enzymatic synthesis of some cephalosporins by kinetically controlled n-acylation (kcna) of different cephem nuclei, and compared with the penicillin g acylase (pga) from escherichia coli. the reaction outcomes were dependent on the acylase microbial source and on the type of immobilization support. generally, both enzymes, when immobilized onto hydrophilic resins such as glyoxyl-agarose (activated with aldehyde groups), displ ...200717879093
biodegradative potential and characterization of psychrotolerant polychlorinated biphenyl-degrading marine bacteria isolated from a coastal station in the terra nova bay (ross sea, antarctica).antarctic marine bacteria were screened for their ability to degrade polychlorinated biphenyls (pcb) as the sole carbon and energy source at both 4 degrees c and 15 degrees c. pcb-degrading isolates (7.1%) were identified by sequencing their 16s rdna as pseudoalteromonas, psychrobacter and arthrobacter members. one representative isolate per genera was selected for evaluating the biodegradative potential under laboratory scale and phenotypically characterized. removal of individual pcb congeners ...200717854841
6-aminohexanoate oligomer hydrolases from the alkalophilic bacteria agromyces sp. strain ky5r and kocuria sp. strain ky2.alkalophilic, nylon oligomer-degrading strains, agromyces sp. and kocuria sp., were isolated from the wastewater of a nylon-6 factory and from activated sludge from a sewage disposal plant. the 6-aminohexanoate oligomer hydrolases (nylc) from the alkalophilic strains had 95.8 to 98.6% similarity to the enzyme in neutrophilic arthrobacter sp. but had superior thermostability, activity under alkaline conditions, and affinity for nylon-related substrates, which would be advantageous for biotechnolo ...200717827307
cloning and characterization of a 4-hydroxyphenylacetate 3-hydroxylase from the thermophile geobacillus sp. pa-9.a 4-hydroxyphenylacetic acid (4-hpa) hydroxylase-encoding gene, on a 2.7-kb genomic dna fragment, was cloned from the thermophile geobacillus sp. pa-9. the geobacillus sp. pa-9 4-hpa hydroxylase gene, designated hpah, encodes a protein of 494 amino acids with a predicted molecular mass of 56.269 da. the deduced amino-acid sequence of the hpah gene product displayed <30% amino-acid sequence identity with the larger monooxygenase components of the previously characterized two-component 4-hpa 3-hyd ...200717805928
cloning of a gene cluster involved in the catabolism of p-nitrophenol by arthrobacter sp. strain js443 and characterization of the p-nitrophenol monooxygenase.the npd gene cluster, which encodes the enzymes of a p-nitrophenol catabolic pathway from arthrobacter sp. strain js443, was cloned and sequenced. three genes, npdb, npda1, and npda2, were independently expressed in escherichia coli in order to confirm the identities of their gene products. npda2 is a p-nitrophenol monooxygenase belonging to the two-component flavin-diffusible monooxygenase family of reduced flavin-dependent monooxygenases. npda1 is an nadh-dependent flavin reductase, and npdb i ...200717720792
trapping of a dopaquinone intermediate in the tpq cofactor biogenesis in a copper-containing amine oxidase from arthrobacter globiformis.the biogenesis of the topaquinone (tpq) cofactor of copper amine oxidase (cao) is self-catalyzed and requires copper and molecular oxygen. a dopaquinone intermediate has been proposed to undergo 1,4-addition of a copper-associated water molecule to form the reduced form of tpq (tpq(red)), followed by facile oxidation by o(2) to yield the mature tpq (tpq(ox)). in this study, we have incorporated a lysine residue in the active site of arthrobacter globiformis cao (agao) by site-directed mutagenesi ...200717715921
production of volatile aroma compounds by bacterial strains isolated from different surface-ripened french cheeses.twelve bacterial strains belonging to eight taxonomic groups: brevibacterium linens, microbacterium foliorum, arthrobacter arilaitensis, staphylococcus cohnii, staphylococcus equorum, brachybacterium sp., proteus vulgaris and psychrobacter sp., isolated from different surface-ripened french cheeses, were investigated for their abilities to generate volatile aroma compounds. out of 104 volatile compounds, 54 volatile compounds (identified using dynamic headspace technique coupled with gas chromat ...200717701035
continuous deodorization and bacterial community analysis of a biofilter treating nitrogen-containing gases from swine waste storage pits.a biofilter inoculated with arthrobacter sp. was applied to the simultaneous elimination of trimethylamine (tma) and ammonia (nh3) from the exhaust air of swine waste storage pits. the results showed that the biofilter achieved average removal efficiencies of 96.8+/-2.5% and 97.2+/-2.3% for tma and nh3, respectively. a near-neutral ph (7.3-7.4) was maintained due to the accumulation of acid metabolites and the adsorption of alkaline nh3. low moisture demand, low pressure drop and high biofilm st ...200817697773
[preparation of androsta-1,4-diene-3,17-dione from sterols using mycobacterium neoaurum vkpm as-1656 strain].a product of microbiological cleavage of the sterols side chain, androsta-1,4-diene-3,17-dione, is toxic for bacteria, in particular, actinobacteria of the genera mycobacterium and arthrobacter. sterols were transformed into androsta-1,4-diene-3,17-dione by culturing the m. neoaurum vkpm an-1656 strain in a high yield, provided that a sorbent was used for elimination of contact between the bacterial cells and the product. unlike the cholesterol side chain, the more branched chains of phytosterol ...200717682396
complete degradation of butyl benzyl phthalate by a defined bacterial consortium: role of individual isolates in the assimilation pathway.two bacterial strains, in consortium, were isolated by enrichment techniques from municipal waste-contaminated soil, which utilized butyl benzyl phthalate (bbp) as the sole carbon source. one of the isolates was identified as arthrobacter sp. strain wy and the other one as acinetobacter sp. strain fw based on the morphological, nutritional and biochemical characteristics and 16s rrna sequence analysis. various metabolites of bbp engendered by arthrobacter sp. strain wy were isolated and identifi ...200817669462
degradation of pentachlorophenol by pure and mixed cultures in two different soils.pentachlorophenol (pcp) is the second highest volume pesticide used in the united states. it is a mutagenic compound whose exposure poses significant health effects, one of the most desirable, environmentally friendly treatment methods is bioremediation. for soil-based contamination, the effectiveness of bioremediation will also be affected by the presence of an active indigenous population, sorption of the contaminant onto the soil, and environmental parameters.200717668821
[lignite microorganisms].the first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. according to direct microscopy, the abundance of bacteria was about 10(7) cells/g. about 70% of cells had intact cell membranes and small size, which points to their anabiotic state. the fungal mycelium length was no more than 1 m. lignite inoculation onto solid glucose-yeast-peptone medium allowed as to isolate bacteria of the genera bacillus, rhodococcus, arthrobacter, micrococ ...200717668464
biodegradation and bioremediation of endosulfan contaminated soil.among the three mixed bacterial culture ae, be, and ce, developed by enrichment technique with endosulfan as sole carbon source, consortium ce was found to be the most efficient with 72% and 87% degradation of alpha-endosulfan and beta-endosulfan, respectively, in 20 days. in soil microcosm, consortium ae, be and ce degraded alpha-endosulfan by 57%, 88% and 91%, respectively, whereas beta-endosulfan was degraded by 4%, 60% and 67% after 30 days. ochrobacterum sp., arthrobacter sp., and burkholde ...200817646098
partial purification and chemical characterization of a glycoprotein (putative hydrocolloid) emulsifier produced by a marine bacterium antarctobacter.during screening for novel emulsifiers and surfactants, a marine alphaproteobacterium, antarctobacter sp. tg22, was isolated and selected for its production of an extracellular emulsifying agent, ae22. this emulsifier was produced optimally in a low-nutrient seawater medium supplemented with glucose and was extractable by cold ethanol precipitation of the high-molecular-weight fraction (>100 kda). production of ae22 commenced towards the late exponential phase of growth, with maximum emulsifying ...200717641887
the distribution of acetohydroxyacid synthase in soil bacteria.most bacteria possess the enzyme acetohydroxyacid synthase, which is used to produce branched-chain amino acids. enteric bacteria contain several isozymes suited to different conditions, but the distribution of acetohydroxyacid synthase in soil bacteria is largely unknown. growth experiments confirmed that escherichia coli, salmonella enterica serotype typhimurium, and enterobacter aerogenes contain isozymes of acetohydroxyacid synthase, allowing the bacteria to grow in the presence of valine (w ...200817624809
glycinebetaine accumulation is more effective in chloroplasts than in the cytosol for protecting transgenic tomato plants against abiotic stress.tomato (lycopersicon esculentum mill. cv. moneymaker) plants were transformed with a gene for choline oxidase (coda) from arthrobacter globiformis. the gene product (coda) was targeted to the chloroplasts (chl-coda), cytosol (cyt-coda) or both compartments simultaneously (chlcyt-coda). these three transgenic plant types accumulated different amounts and proportions of glycinebetaine (gb) in their chloroplasts and cytosol. targeting coda to either the cytosol or both compartments simultaneously i ...200717617827
synthesis of 4-hydroxyisoleucine by the aldolase-transaminase coupling reaction and basic characterization of the aldolase from arthrobacter simplex aku 626.arthrobacter simplex aku 626 was found to synthesize 4-hydroxyisoleucine from acetaldehyde, alpha-ketobutyrate, and l-glutamate in the presence of escherichia coli harboring the branched chain amino acid transaminase gene (ilve) from e. coli k12 substrain mg1655. by using resting cells of a. simplex aku 626 and e. coli bl21(de3)/pet-15b-ilve, 3.2 mm 4-hydroxyisoleucine was produced from 250 mm acetaldehyde, 75 mm alpha-ketobutyrate, and 100 mm l-glutamate with a molar yield to alpha-ketobutyrate ...200717617727
cultivable bacterial diversity of alkaline lonar lake, india.aerobic, alkaliphilic bacteria were isolated and characterized from water and sediment samples collected in the winter season, january 2002 from alkaline lonar lake, india, having ph 10.5. the total number of microorganisms in the sediment and water samples was found to be 10(2)-10(6) cfu g(-1) and 10(2)-10(4) cfu ml(-1), respectively. one hundred and ninety-six strains were isolated using different enrichment media. to study the bacterial diversity of lonar lake and to select the bacterial stra ...200817604989
stability of microbial communities in goat milk during a lactation year: molecular approaches.the microbial communities in milks from one herd were evaluated during 1-year of lactation, using molecular methods to evaluate their stability and the effect of breeding conditions on their composition. the diversity of microbial communities was measured using two approaches: molecular identification by 16s and 18s rdna sequencing of isolates from counting media (two milks), and direct identification using 16s rdna from clone libraries (six milks). the stability of these communities was evaluat ...200717604934
cloning and characterization of the gene encoding endo-beta-1,3-glucanase from arthrobacter sp. nhb-10.the glua gene, encoding an endo-beta-1,3-glucanase from arthrobacter sp. (strain nhb-10), was cloned and analyzed. the deduced endo-beta-1,3-glucanase amino acid sequence was 750 amino acids long and contained a 42 amino acid signal peptide with a mature protein of 708 amino acids. there was no similarity to known endo-beta-1,3-glucanases, but glua was partially similar to two fungal exo-beta-1,3-glucanases in glycoside hydrolase (gh) family 55. of five possible residues for catalysis and two mo ...200717587693
taxonomic identification, phenanthrene uptake activity, and membrane lipid alterations of the pah degrading arthrobacter sp. strain sphe3.this report describes phenanthrene uptake as well as the effect of phenanthrene on the membrane phospholipid and fatty acid composition in a newly isolated bacterial strain, sphe3, that we taxonomically identified as arthrobacter sp. strain sphe3 is able to utilize phenanthrene as a carbon source at high rates and appears to internalize phenanthrene with two mechanisms: a passive diffusion when cells are grown on glucose, and an inducible active transport system when cells are grown on phenanthr ...200717583808
characterization of aerobic bacterial and fungal microbiota on surfaces of historic scottish monuments.twenty samples were taken from the inner or outer surfaces of stone monuments of six historic scottish buildings and ruins. biofilms developing on mineral substrates were analysed by in situ scanning electron microscopy and cultivation. various methods were used to characterize the isolates including automated ribotyping, rapd and sequencing of the 16s rrna gene for bacteria, and stereomicroscopy and sequencing of the internal transcribed spacers (its) for fungi. most samples contained microbes ...200717583461
identification of the catalytic acid base residue of arthrobacter endo-beta-n-acetylglucosaminidase by chemical rescue of an inactive mutant.arthrobacter endo-beta-n-acetylglucosaminidase (endo-a), a member of glycoside hydrolase (gh) family 85, catalyses the hydrolysis and transglycosylation of asparagine-linked oligosaccharides of glycoproteins with retention of anomeric configuration. glu-173 of endo-a is a catalytically essential amino acid residue, and the corresponding residue is conserved in all gh family 85 members. the catalytic activity of endo-a e173a mutant was rescued by the addition of sodium azide or sodium formate. fu ...200717567654
crystallization and preliminary x-ray analysis of 1h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase from arthrobacter nitroguajacolicus rü61a: a cofactor-devoid dioxygenase of the alpha/beta-hydrolase-fold superfamily.1h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase (hod) is a cofactor-devoid dioxygenase that is involved in the anthranilate pathway of quinaldine degradation. hod has been proposed to belong to the alpha/beta-hydrolase-fold superfamily of enzymes. n-terminally his6-tagged hod has been crystallized by the hanging-drop vapour-diffusion method using sodium/potassium tartrate as a precipitant and cucl2 as an additive. the structure was solved by the single anomalous dispersion (sad) technique using dat ...200717565176
crystallization and diffraction data of 1h-3-hydroxy-4-oxoquinoline 2,4-dioxygenase: a cofactor-free oxygenase of the alpha/beta-hydrolase family.1h-3-hydroxy-4-oxoquinoline 2,4-dioxygenase (qdo) from pseudomonas putida 33/1 catalyses the oxygenolysis of 1h-3-hydroxy-4-oxoquinoline to form n-formylanthranilic acid and carbon monoxide without the aid of cofactors. both n-terminally his6-tagged and native qdo were overexpressed in escherichia coli and purified by conventional chromatographic procedures. untagged qdo, but not his6-tagged qdo, was crystallized by the vapour-diffusion method, giving hexagonal bipyramid crystals belonging to sp ...200717565175
a novel strategy for enzymatic synthesis of 4-hydroxyisoleucine: identification of an enzyme possessing hmkp (4-hydroxy-3-methyl-2-keto-pentanoate) aldolase activity.a two-step enzymatic synthesis process of 4-hydroxyisoleucine is suggested. in the first step, the aldol condensation of acetaldehyde and alpha-ketobutyrate catalyzed by specific aldolase results in the formation of 4-hydroxy-3-methyl-2-keto-pentanoate (hmkp). in the second step, amination of hmkp by the branched-chain amino acid aminotransferase leads to synthesis of 4-hydroxyisoleucine. an enzyme possessing hmkp aldolase activity (ashpal) was purified 2500-fold from a crude extract of arthroba ...200717559390
biotransformation of d-methionine into l-methionine in the cascade of four enzymes.d-methionine was converted to l-methionine in a reaction system where four enzymes were used. d-amino acid oxidase (d-aao) from arthrobacter protophormiae was used for the complete conversion of d-methionine to 2-oxo-4-methylthiobutyric acid. catalase was added to prevent 2-oxo-4-methylthiobutyric acid decarboxylation. in the second reaction step, l-phenylalanine dehydrogenase (l-phedh) from rhodococcus sp. was used to convert 2- oxo-4-methylthiobutyric acid to l-methionine, and formate dehydrog ...200717534960
an internal equilibrium preorganizes the enzyme-substrate complex for hydride tunneling in choline oxidase.the hydride transfer reaction catalyzed by choline oxidase under irreversible regime, i.e., at saturating oxygen, was shown in a recent study to occur quantum mechanically within a highly preorganized active site, with the reactive configuration for hydride tunneling being minimally affected by environmental vibrations of the reaction coordinate other than those affecting the distance between the alpha-carbon of the choline alkoxide substrate and the n(5) atom of the enzyme-bound flavin cofactor ...200717472346
a two-component small multidrug resistance pump functions as a metabolic valve during nicotine catabolism by arthrobacter nicotinovorans.the genes nepab of a small multidrug resistance (smr) pump were identified as part of the pao1-encoded nicotine regulon responsible for nicotine catabolism in arthrobacter nicotinovorans. when [(14)c]nicotine was added to the growth medium the bacteria exported the (14)c-labelled end product of nicotine catabolism, methylamine. in the presence of the proton-motive force inhibitors 2,4-dinitrophenol (dnp), carbonyl cyanide m-chlorophenylhydrazone (cccp) or the proton ionophore nigericin, export o ...200717464069
overexpression and functional analysis of cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2.cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2 was overexpressed in escherichia coli using the cold expression system and the recombinant enzyme, rbglap, was characterized. the purified rbglap exhibited similar enzymatic properties to the native enzyme, e.g., (i) it had high activity at 0 degrees c, (ii) its optimum temperature and ph were 10 degrees c and 8.0, respectively, and (iii) it was possible to rapidly inactivate the rbglap at 50 degrees c in 5 min. moreov ...200717459724
expression of ksdd gene encoding 3-ketosteroid-delta1-dehydrogenase from arthrobacter simplex in bacillus improve ksdh enzyme activity and the transformation level for androst-4-ene-3,17-dione.200717451526
structure and denaturation of 4-chlorobenzoyl coenzyme a dehalogenase from arthrobacter sp. strain tm-1.the secondary structure of the trimeric protein 4-chlorobenzoyl coenzyme a dehalogenase from arthrobacter sp. strain tm-1, the second of three enzymes involved in the dechlorination of 4-chlorobenzoate to form 4-hydroxybenzoate, has been examined. e(mm) for the enzyme was 12.59. analysis by circular dichroism spectrometry in the far uv indicated that 4-chlorobenzoyl coenzyme a dehalogenase was composed mostly of alpha-helix (56%) with lesser amounts of random coil (21%), beta-turn (13%) and beta ...200817431803
chlamydomonas reinhardtii, a model system for functional validation of abiotic stress responsive genes.stress tolerance is a multigenic character and there are many stress responsive genes, which are stress specific. although many of these have been cloned, their functional significance remains fragmentary. hence it is important to identify the relevant stress genes involved in altering the metabolism for adaptation. overexpression is one of the several approaches and chlamydomonas is a suitable system to study the functional relevance of stress genes. stress responses can only be assessed on pri ...200717431668
[obtaining and characterization of dna-containing micromummies of yeasts and gram-positive bacteria with enhanced cell wall permeability: application in pcr].the procedure of obtaining dna-containing cell envelopes ("micromummies") of bacteria, yeasts, and fungi using chaotropic salts has been developed previously and the possibility of their direct application in pcr has been demonstrated. the fine structure of micromummies has been studied by electron microscopic methods. this work has demonstrated that additional treatment of micromummies of yeasts and gram-positive bacteria with proteinase k results in hydrolytic degradation of cell proteins and ...200717410877
[reaction of microorganisms to the digestive fluid of the earthworms].the reaction of soil bacteria and fungi to the digestive fluid of the earthworm aporrectodea caliginosa was studied. the fluid was obtained by centrifugation of the native enzymes of the digestive tract. the inhibition of growth of certain bacteria, spores, and fungal hyphae under the effect of extracts from the anterior and middle sections of the digestive tract of a. caliginosa was discovered for the first time. in bacteria, microcolony formation was inhibited as early as 20-30 s after the app ...200717410875
the characteristics of rhizosphere microbes associated with plants in arsenic-contaminated soils from cattle dip sites.soil microorganisms and plants were studied in samples of arsenic-contaminated soil from two cattle dip sites. the aim was to delineate the parameters that will determine the feasibility of future remediation by growing arsenic-accumulating plants, including the identity and characteristics of some rhizosphere soil microbes. the soil samples contained high total, but low soluble arsenic concentrations which, together with other properties, resembled the previously reported characteristics of dip ...200717407787
metabolic activity and phylogenetic diversity of reed (phragmites australis) periphyton bacterial communities in a hungarian shallow soda the present study, the species composition and potential metabolic activities of bacterial communities of reed phragmites australis (cav.) (trin. ex steudel) periphyton from lake velencei were studied by cultivation-based and metabolic fingerprinting methods. serially diluted spring biofilm samples were used to test the community-level physiological profiling (clpp) using biolog microplates, and for plating onto different media. on the basis of their morphological, biochemical, and physiologi ...200717406774
isolation and characterization of four gram-positive nickel-tolerant microorganisms from contaminated sediments.microbial communities from riparian sediments contaminated with high levels of ni and u were examined for metal-tolerant microorganisms. isolation of four aerobic ni-tolerant, gram-positive heterotrophic bacteria indicated selection pressure from ni. these isolates were identified as arthrobacter oxydans nr-1, streptomyces galbus nr-2, streptomyces aureofaciens nr-3, and kitasatospora cystarginea nr-4 based on partial 16s rdna sequences. a functional gene microarray containing gene probes for fu ...200717404787
growth and physiological response of arthrobacter protophormiae rkj100 toward higher concentrations of o-nitrobenzoate and p-hydroxybenzoate.bioremediation of sites that are heavily contaminated with pollutant chemicals is a challenge as most of the microorganisms cannot tolerate higher concentrations of toxic compounds. only a few strains of the genus pseudomonas have been studied for their tolerance toward the higher concentrations of aromatic pollutant compounds, a phenomenon that is accompanied by various physiological changes. in the present study we have characterized the growth response and physiological changes (adaptations) ...200717391368
cloning of the arthrobacter sp. fg1 dehalogenase genes and construction of hybrid pathways in pseudomonas putida arthrobacter strain, able to utilize 4-chlorobenzoic acid as the sole carbon and energy source, was isolated and characterized. the first step of the catabolic pathway was found to proceed via a hydrolytic dehalogenation that leads to the formation of 4-hydroxybenzoic acid. the dehalogenase encoding genes (fcb) were sequenced and found highly homologous to and organized as those of other 4-chlorobenzoic acid degrading arthrobacter strains. the fcb genes were cloned and successfully expressed ...200717384944
seasonal variation of sediment toxicity in the rivers dommel and elbe.contaminated sediment in the river basin has become a source of pollution with increasing importance to the aquatic ecosystem downstream. to monitor the temporal changes of the sediment bound contaminants in the river elbe and the river dommel monthly toxicity tests were applied to layered sediment and river water samples over the course of 10 months. there is an indication that contaminated sediments upstream adversely affected sediments downstream, but this process did not cause a continuous i ...200717379366
biosorption of cr (vi) using a bacterial biofilm supported on granular activated carbon and on zeolite.two mini-columns partially filled with granular activated carbon (gac) and/or a natural zeolite, covered by a bacterial biofilm of arthrobacter viscosus, were used in a continuous flow system to remove cr (vi) from solutions with initial concentration of 70mg/l and a working ph ranging between 4.5 and 5.5. three different set-up's were used: two columns in series filled gac covered with a biofilm, two columns in series filled with zeolite covered with a biofilm and a column filled with gac follo ...200817368891
the coda transgene for glycinebetaine synthesis increases the size of flowers and fruits in tomato.the tolerance of various species of plant to abiotic stress has been enhanced by genetic engineering with certain genes. however, the use of such transgenes is often associated with negative effects on growth and productivity under non-stress conditions. the coda gene from arthrobacter globiformis is of particular interest with respect to the engineering of desirable productive traits in crop plants. the expression of this gene in tomato plants resulted in significantly enlarged flowers and frui ...200717362485
[a model study of pesticide biodegradation in soil].this study addresses the efficiency of microbial preparations to degrade pesticide residues in soil. a method to degrade pesticides dnoc and pendimethalin using pseudomonas and arthrobacter bacteria with a fertilizer is described.200717352205
[function and structure of nad kinase: the key enzyme for biosynthesis of nadp (h)]. 200717352189
solar-based detoxification of phenol and p-nitrophenol by sequential tio2 photocatalysis and photosynthetically aerated biological treatment.simulated solar uv/tio(2) photocatalysis was efficient to detoxify a mixture of 100 mgphenoll(-1) and 50 mgp-nitrophenol (pnp) l(-1) and allow the subsequent biodegradation of the remaining pollutants and their photocatalytic products under photosynthetic aeration with chlorella vulgaris. photocatalytic degradation of phenol and pnp was well described by pseudo-first order kinetics (r(2)>0.98) with removal rate constants of 1.9x10(-4) and 2.8x10(-4)min(-1), respectively, when the pollutants were ...200717350074
complete nucleotide sequence of the 113-kilobase linear catabolic plasmid pal1 of arthrobacter nitroguajacolicus rü61a and transcriptional analysis of genes involved in quinaldine degradation.the nucleotide sequence of the linear catabolic plasmid pal1 from the 2-methylquinoline (quinaldine)-degrading strain arthrobacter nitroguajacolicus rü61a comprises 112,992 bp. a total of 103 open reading frames (orfs) were identified on pal1, 49 of which had no annotatable function. the orfs were assigned to the following functional groups: (i) catabolism of quinaldine and anthranilate, (ii) conjugation, and (iii) plasmid maintenance and dna replication and repair. the genes for conversion of q ...200717337569
mineralization of diuron [3-(3,4-dichlorophenyl)-1, 1-dimethylurea] by co-immobilized arthrobacter sp. and delftia acidovorans.mineralization of diuron has not been previously demonstrated despite the availability of some bacteria to degrade diuron into 3,4-dichloroaniline (3,4-dca) and others that can mineralize 3,4-dca. a bacterial co-culture of arthrobacter sp. n4 and delftia acidovorans w34, which respectively degraded diuron (20 mg l(-1)) to 3,4-dca and mineralized 3,4-dca, were able to mineralize diuron. total diuron mineralization (20 mg l(-1)) was achieved with free cells in co-culture. when the bacteria were im ...200717333465
microorganisms isolated from the water phase of tropospheric clouds at the puy de dôme: major groups and growth abilities at low temperatures.this work constitutes the first large report on aerobic cultivable microorganisms present in cloud water. seven cloud-event samples were collected at the puy de dôme summit, and cultivation was performed leading to the isolation of 71 bacterial, 42 fungal and 15 yeast strains. most of the fungi isolated were of cladosporium or trametes affiliation, and yeasts were of cryptococcus affiliation. bacteria, identified on the basis of their 16s rrna gene sequence, were found to belong to actinobacteri ...200717328765
isolation and characterization of novel atrazine-degrading microorganisms from an agricultural soil.six previously undescribed microorganisms capable of atrazine degradation were isolated from an agricultural soil that received repeated exposures of the commonly used herbicides atrazine and acetochlor. these isolates are all gram-positive and group with microorganisms in the genera nocardioides and arthrobacter, both of which contain previously described atrazine degraders. all six isolates were capable of utilizing atrazine as a sole nitrogen source when provided with glucose as a separate ca ...200717318536
[isolation, degradation and phylogenetic analysis of methylparathion degradative strain x4].the strain x4 was isolated from polluted wastes of shandong huayang pesticide chemical industry group co., ltd. it was cultured with methylparathion and p-nitrophenol, a kind of intermediate during methylparathion degrading process, and used them as the sole carbon source and decomposed them into carbon dioxide and wastes. it is identified as arthrobacter sp. by means of a series of tests, and it has visible sphere-pole variable cycle. it is bacilliform when it is cultured in nutrient broth medi ...200617302165
esta from arthrobacter nitroguajacolicus rü61a, a thermo- and solvent-tolerant carboxylesterase related to class c beta-lactamases.the esta gene encoding a novel cytoplasmic carboxylesterase from arthrobacter nitroguajacolicus rü61a was expressed in escherichia coli. sequence analysis and secondary structure predictions suggested that esta belongs to the family viii esterases, which are related to class c beta-lactamases. the s-x-x-k motif that in beta-lactamases contains the catalytic nucleophile, and a putative active-site tyrosine residue are conserved in esta. the native molecular mass of hexahistidine-tagged (his6) est ...200717294326
an nad(p)h-nicotine blue oxidoreductase is part of the nicotine regulon and may protect arthrobacter nicotinovorans from oxidative stress during nicotine nad(p)h-nicotine blue (quinone) oxidoreductase was discovered as a member of the nicotine catabolic pathway of arthrobacter nicotinovorans. transcriptional analysis and electromobility shift assays showed that the enzyme gene was expressed in a nicotine-dependent manner under the control of the transcriptional activator pmfr and thus was part of the nicotine regulon of a. nicotinovorans. the flavin mononucleotide-containing enzyme uses nadh and, with lower efficiency, nadph to reduce, by a tw ...200717293530
overproduction and characterization of a recombinant d-amino acid oxidase from arthrobacter protophormiae.a screening of soil samples for d-amino acid oxidase (d-aao) activity led to the isolation and identification of the gram-positive bacterium arthrobacter protophormiae. after purification of the wild-type d-aao, the gene sequence was determined and designated dao. an alignment of the deduced primary structure with eukaryotic d-aaos and d-aspartate oxidases showed that the d-aao from a. protophormiae contains five of six conserved regions; the c-terminal type 1 peroxisomal targeting signal that i ...200717279391
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 ...200717276484
structure and action of a c-c bond cleaving alpha/beta-hydrolase involved in nicotine degradation.the enzyme 2,6-dihydroxy-pseudo-oxynicotine hydrolase from the nicotine-degradation pathway of arthrobacter nicotinovorans was crystallized and the structure was determined by an x-ray diffraction analysis at 2.1 a resolution. the enzyme belongs to the alpha/beta-hydrolase family as derived from the chain-fold and from the presence of a catalytic triad with its oxyanion hole at the common position. this relationship assigns a pocket lined by the catalytic triad as the active center. the asymmetr ...200717275835
utilization and degradation of imazaquin by a naturally occurring isolate of arthrobacter crystallopoietes.a species of bacteria that is capable of utilizing imazaquin as the sole carbon source was isolated from soil with repeated imazaquin applications, and was identified as arthrobacter crystallopoietes (designated as strain "wwx-1"). this isolate degrades imazaquin as high as 200 microg ml-1, and the estimated dissipation half-lives increased from 1.51 d for the treatment at 50 microg ml-1 to 4.75 d for 200 microg ml-1. optimal growth of wwx-1 in mineral salt medium with 50 microg ml-1 imazaquin w ...200717267013
adaptation of the psychrotroph arthrobacter chlorophenolicus a6 to growth temperature and the presence of phenols by changes in the anteiso/iso ratio of branched fatty acids.arthrobacter chlorophenolicus is a previously described gram-positive bacterium capable of degrading high concentrations of several phenolic compounds under optimal mesophilic (28 degrees c) as well as psychrophilic (5 degrees c) conditions. however, the exact mechanisms by which this organism is able to tolerate such extremes in temperature and high levels of toxic compounds are currently not known. in this study, we monitored changes in the fatty acid composition of the cell membrane under dif ...200717233723
amperometric biosensor for the determination of amperometric biosensor for the determination of creatine was developed. the carbon rod electrode surface was coated with sarcosine oxidase (sox) and creatine amidinohydrolase by cross-linking under glutaraldehyde vapour. the sox from arthrobacter sp. 1-1 n was purified and previously used for creation of a creatine biosensor. the natural sox electron acceptor, oxygen, was replaced by an [fe(cn)(6)](3-) /[ fe(cn)(6)](4-) redox mediating system, which allowed amperometric detection of an analyt ...200717221239
strong impact on the polycyclic aromatic hydrocarbon (pah)-degrading community of a pah-polluted soil but marginal effect on pah degradation when priming with bioremediated soil dominated by mycobacteria.bioaugmentation of soil polluted with polycyclic aromatic hydrocarbons (pahs) is often disappointing because of the low survival rate and low activity of the introduced degrader bacteria. we therefore investigated the possibility of priming pah degradation in soil by adding 2% of bioremediated soil with a high capacity for pah degradation. the culturable pah-degrading community of the bioremediated primer soil was dominated by mycobacterium spp. a microcosm containing pristine soil artificially ...200717209064
nod2/card15 disease associations other than crohn's this moment, few confirmed associations between nod2 mutations and diseases other than crohn's disease (cd) and blau syndrome (bs) have been reported, but research is ongoing in several fields where a genetic susceptibility factor and/or a role for the innate immune system is suspected. whether the crohn's-associated card15 mutations lead to a loss or gain of function of the nod2 receptor is subject to controversy, and by which mechanisms this change in function might increase the susceptibil ...200717206682
variations in t-rflp profiles with differing chemistries of fluorescent dyes used for labeling the pcr primers.culture independent molecular methods have emerged as indispensable tools for studying microbial community structure and dynamics in natural habitats, since they allow a closer look at microbial diversity that is not reflected by culturing techniques. terminal restriction fragment length polymorphism (t-rflp) analysis is one of the informative and widely used techniques for such studies. however, the method has a few limitations to predict microbial community structure with significant accuracy. ...200717196691
secrets of soil survival revealed by the genome sequence of arthrobacter aurescens tc1.arthrobacter sp. strains are among the most frequently isolated, indigenous, aerobic bacterial genera found in soils. member of the genus are metabolically and ecologically diverse and have the ability to survive in environmentally harsh conditions for extended periods of time. the genome of arthrobacter aurescens strain tc1, which was originally isolated from soil at an atrazine spill site, is composed of a single 4,597,686 basepair (bp) circular chromosome and two circular plasmids, ptc1 and p ...200617194220
biodiversity of bacterial ecosystems in traditional egyptian domiati cheese.bacterial biodiversity occurring in traditional egyptian soft domiati cheese was studied by pcr-temporal temperature gel electrophoresis (ttge) and pcr-denaturing gradient gel electrophoresis (dgge). bands were identified using a reference species database (j.-c. ogier et al., appl. environ. microbiol. 70:5628-5643, 2004); de novo bands having nonidentified migration patterns were identified by dna sequencing. results reveal a novel bacterial profile and extensive bacterial biodiversity in domia ...200717189434
microbially mediated cadmium sorption/desorption processes in soil amended with sewage sludge.a multi-compartment system was used to study the importance of microorganisms for cd desorption from soil amended with sewage sludge and simultaneous resorption of the mobilized metal by soil constituents. using this system made it possible to study the participation of microorganisms (arthrobacter, trichoderma), montmorillonite, humic acids, and iron oxides in resorption of the released cd. a filter-sterilized water extract of root-free soil of ph 6.7 (rf) or rf supplemented with glucose (rfg) ...200717182077
coryneform bacteria in semen of chronic prostatitis patients.our aim was to compare the presence and species composition of coryneform bacteria in chronic prostatitis patients and controls. semen of 50 men with inflammatory prostatitis and 59 controls (without pelvic pain/discomfort complaints and leukocytospermia) was investigated. first-catch urine was additionally investigated in 36 men (30 with and 6 without prostatitis). coryneform bacteria were found in semen of 76% men with inflammatory prostatitis and 83% controls. more than half of the isolates w ...200717163953
trans-generational immune priming in a social insect.detecting functional homology between invertebrate and vertebrate immunity is of interest in terms of understanding the dynamics and evolution of immune systems. trans-generational effects on immunity are well known from vertebrates, but their existence in invertebrates remains controversial. earlier work on invertebrates has interpreted increased offspring resistance to pathogens as trans-generational immune priming. however, interpretation of these earlier studies involves some caveats and thu ...200517148213
crystallization and x-ray diffraction analysis of 6-aminohexanoate-cyclic-dimer hydrolase from arthrobacter sp. ki72.6-aminohexanoate-cyclic-dimer hydrolase (ei) from arthrobacter sp. ki72 was expressed in escherichia coli and purified by anion-exchange chromatography. ei was crystallized by the sitting-drop vapour-diffusion method with sodium citrate as precipitant in imidazole buffer ph 8.0. the crystal is hexagonal, with unit-cell parameters a = b = 130.75, c = 58.23 a. diffraction data were collected from native and mercury(ii) dichloride-derivative crystals to resolutions of 1.90 and 2.06 a, respectively.200617142898
n-ethylmaleimide-resistant acyl-coenzyme a oxidase from arthrobacter ureafaciens nbrc 12140: molecular cloning, gene expression and characterization of the recombinant enzyme.n-ethylmaleimide (nem)-resistant acyl-coenzyme a oxidase (aco) has been desired for the determination of free fatty acids (ffas). in order to meet this demand, we prepared recombinant aco from arthrobacter ureafaciens nbrc 12140. the coding region of the gene was 2109, encoding a protein of 703 amino acids with a predicted molecular mass of 76.5 kda. the heterologous expression level in escherichia coli was 520-fold higher than that in the native strain. the purified enzyme retained more than 60 ...200717141592
evolution of catabolic pathways: genomic insights into microbial s-triazine metabolism. 200717114259
the copper-containing amine oxidase from arthrobacter globiformis: refinement at 1.55 and 2.20 a resolution in two crystal forms.copper-containing amine oxidases are found in all the major kingdoms of life. they catalyse the oxidation of organic amines in the presence of molecular dioxygen to aldehydes and hydrogen peroxide. the catalytic centres contain a cu atom and a topaquinone cofactor formed autocatalytically from a tyrosine residue in the presence of cu and molecular oxygen. the structure of the cu-containing amine oxidase from arthrobacter globiformis, which was previously refined at 1.8 a resolution in space grou ...200617077478
ecotoxicological assessment of sediment, suspended matter and water samples in the upper danube river. a pilot study in search for the causes for the decline of fish catches.goals, scope and background: fish populations, especially those of the grayling (thymallus thymallus), have declined over the last two decades in the upper danube river between sigmaringen and ulm, despite intensive and continuous stocking and improvement of water quality since the 1970s. similar problems have been reported for other rivers, e.g. in switzerland, great britain, the united states and canada. in order to assess if ecotoxicological effects might be related to the decline in fish cat ...200617067025
contribution of ethylamine degrading bacteria to atrazine degradation in soils.bacterial communities that cooperatively degrade atrazine commonly consist of diverse species in which the genes for atrazine dechlorination and dealkylation are variously distributed among different species. normally, the first step in degradation of atrazine involves dechlorination mediated by atza, followed by stepwise dealkylation to yield either n-ethylammelide or n-isopropylammelide. as the liberated alkylamine moieties are constituents of many organic molecules other than atrazine, it is ...200617064268
high-performance ce: an effective method to study lactonization of alpha2,8-linked oligosialic acid.a sensitive and efficient method using high-performance ce (hpce) and neuraminidase hydrolysis was developed to study the lactonization and hydrolysis of alpha2,8-pentasialic acid. eleven lactone species of pentasialic acid formed in glacial acetic acid were detected and classified into three groups based on the number of carboxylic acids: monolactones with four carboxylic acids, dilactones with three carboxylic acids, and trilactones with two carboxylic acids. these lactones eluted between the ...200617054086
n-acetylanthranilate amidase from arthrobacter nitroguajacolicus rü61a, an alpha/beta-hydrolase-fold protein active towards aryl-acylamides and -esters, and properties of its cysteine-deficient variant.n-acetylanthranilate amidase (amq), a 32.8-kda monomeric amide hydrolase, is involved in quinaldine degradation by arthrobacter nitroguajacolicus rü61a. sequence analysis and secondary structure predictions indicated that amq is related to carboxylesterases and belongs to the alpha/beta-hydrolase-fold superfamily of enzymes; inactivation of (his(6)-tagged) amq by phenylmethanesulfonyl fluoride and diethyl pyrocarbonate and replacement of conserved residues suggested a catalytic triad consisting ...200617041061
growth kinetics of microorganisms isolated from alaskan soil and permafrost in solid media frozen down to -35 degrees c.we developed a procedure to culture microorganisms below freezing point on solid media (cellulose powder or plastic film) with ethanol as the sole carbon source without using artificial antifreezes. enrichment from soil and permafrost obtained on such frozen solid media contained mainly fungi, and further purification resulted in isolation of basidiomycetous yeasts of the genera mrakia and leucosporidium as well as ascomycetous fungi of the genus geomyces. contrary to solid frozen media, the enr ...200717026514
cultivation-independent examination of horizontal transfer and host range of an incp-1 plasmid among gram-positive and gram-negative bacteria indigenous to the barley rhizosphere.the host range and transfer frequency of an incp-1 plasmid (pkjk10) among indigenous bacteria in the barley rhizosphere was investigated. a new flow cytometry-based cultivation-independent method for enumeration and sorting of transconjugants for subsequent 16s rrna gene classification was used. indigenous transconjugant rhizosphere bacteria were collected by fluorescence-activated cell sorting and identified by cloning and sequencing of 16s rrna genes from the sorted cells. the host range of th ...200617021220
plantibacter auratus sp. nov., in the family microbacteriaceae.strain ncimb 9991(t) is a gram-positive, short rod-shaped, yellow-pigmented bacterium, with a high dna g+c content, and was originally deposited in 1967 as arthrobacter sp. the bacterium is aerobic, non-motile, catalase-positive and oxidase-negative. comparative 16s rrna gene sequencing studies demonstrated that this strain was highly related genealogically to plantibacter flavus dsm 14012(t). strain iam 14817(t) (=ncimb 9991(t)) has the following characteristics: the predominant menaquinones ar ...200617012557
functional analysis of the twin-arginine translocation pathway in corynebacterium glutamicum atcc 13869.compared to those of other gram-positive bacteria, the genetic structure of the corynebacterium glutamicum tat system is unique in that it contains the tate gene in addition to tata, tatb, and tatc. the tate homologue has been detected only in the genomes of gram-negative enterobacteria. to assess the function of the c. glutamicum tat pathway, we cloned the tata, tatb, tatc, and tate genes from c. glutamicum atcc 13869 and constructed mutants carrying deletions of each tat gene or of both the ta ...200616997984
epithermal neutron activation analysis of cr(vi)-reducer basalt-inhabiting bacteria.epithermal neutron activation analysis (enaa) has been applied to study elemental composition of cr(vi)-reducer bacteria isolated from polluted basalts from the republic of georgia. cr(vi)-reducing ability of the bacteria was examined by electron spin resonance, demonstrating that the bacteria differ in their rates of cr(vi) reduction. a well-pronounced correlation between the ability of the bacteria to accumulate cr(v) and their ability to reduce cr(v) to cr(iii) observed in our experiments is ...200616970299
mechanism of fad reduction and role of active site residues his-225 and tyr-259 in arthrobacter globiformis dimethylglycine oxidase: analysis of mutant structure and catalytic function.residues his-225 and tyr-259 are located close to the fad in the dehydrogenase active site of the bifunctional dimethylglycine oxidase (dmgo) of arthrobacter globiformis. we have suggested [leys, d., basran, j., and scrutton, n. s. (2003) embo j. 22, 4038-4048] that these residues are involved in abstraction of a proton from the substrate amine group of dimethylglycine prior to c-h bond breakage and fad reduction. to investigate this proposal, we have isolated two mutant forms of dmgo in which ( ...200616964976
6-hydroxy-nicotine-inducible multilevel transgene control in mammalian cells.the precise control of transgene expression is essential for biopharmaceutical manufacturing, gene therapy and tissue engineering. we have designed a novel conditional transcription technology, which enables reversible induction, repression and adjustment of desired transgene expression using the clinically inert 6-hydroxy-nicotine (6hnic). the 6-hydroxy-nicotine oxidase (6hno) repressor (hdnor), which manages nicotine metabolism in arthrobacter nicotinovorans pao1 by binding to a specific opera ...200616962351
characterization of bacterial isolates from industrial wastewater according to probable modes of hexadecane uptake.bacterial isolates from industrial wastewater were characterized according to probable modes of hexadecane uptake based on data for cell surface hydrophobicity, emulsifying activity, glycoside content and surface tension of cell-free culture medium. the results obtained suggested that both modes of biosurfactant-enhanced hexadecane uptake by bacterial strains take place, direct uptake and alkane transfer. the increase in cell surface hydrophobicity and glycoside production by the strains suggest ...200816962302
chromium(v) complexes generated in arthrobacter oxydans by simulation analysis of epr spectra.chromium(v) is an intermediate formed during the reduction of cr(vi) to cr(iii) compounds by various bacteria. however, little is known about the nature, localization and reactivity of cr(v) species in microbial systems. electron paramagnetic resonance (epr) spectroscopy was used to study the nature of cr(v) complexes generated in basalt-inhabiting gram-positive arthrobacter oxydans bacteria after exposure to high concentrations of cr(vi). numerical simulations of the epr spectroscopic data prov ...200616959323
mutational analysis of 6-aminohexanoate-dimer hydrolase: relationship between nylon oligomer hydrolytic and esterolytic activities.carboxylesterase (eii') from arthrobacter sp. ki72 has 88% homology to 6-aminohexanoate-dimer hydrolase (eii) and possesses ca. 0.5% of the level of 6-aminohexanoate-linear dimer (ald)-hydrolytic activity of eii. to study relationship between ald-hydrolytic and esterolytic activities, random mutations were introduced into the gene for hyb-24 (an eii/eii' hybrid with the majority of the sequence deriving for eii' and possessing an eii'-like level of ald-hydrolytic activity). either a g181d or a d ...200616949580
biotransformation of isoeugenol to vanillin by pseudomonas putida ie27 cells.the ability to produce vanillin and/or vanillic acid from isoeugenol was screened using resting cells of various bacteria. the vanillin- and/or vanillic-acid-producing activities were observed in strains belonging to the genera achromobacter, aeromonas, agrobacerium, alcaligenes, arthrobacter, bacillus, micrococcus, pseudomonas, rhodobacter, and rhodococcus. strain ie27, a soil isolate showing the highest vanillin-producing activity, was identified as pseudomonas putida. we optimized the culture ...200716944125
changes of bacterial diversity and main flora in chilled pork during storage using pcr-dgge.this study was designed to explore the bacterial diversity and the main flora in chilled pork by polymerase chain reaction-denaturing gradient gel electrophoresis (pcr-dgge). longissimus muscle was removed from pork carcasses at 24 h postmortem. the muscle was tray- and vacuum-packaged at 4 degrees c for 2, 4, 7 days to extract the bacteria total dna, respectively. the results indicated that the bacterial diversity of chilled pork decreased with storage time regardless of packaging method. nine ...200616943058
characterization of a carbohydrate epitope defined by the monoclonal antibody h185: sialic acid o-acetylation on epithelial cell-surface mucins.sialic acids comprise a large family of derivatives of neuraminic acid containing methyl, acetyl, sulfate, and phosphate among other groups, which confer specific physicochemical properties (e.g., hydrophobicity and resistance to hydrolases) to the molecules carrying them. several years ago, a monoclonal antibody, designated h185, was developed, which binds to cell membranes of human corneal, conjunctival, laryngeal, and vaginal epithelia and whose distribution is altered on the ocular surface o ...200616940404
intramolecular electron transfer rate between active-site copper and tpq in arthrobacter globiformis amine oxidase.copper amine oxidases catalyze the oxidative deamination of primary amines operating through a ping-pong bi bi mechanism, divided into reductive and oxidative half-reactions. considerable debate still exists regarding the role of copper in the oxidative half-reaction, where o2 is reduced to h2o2. substrate-reduced amine oxidases display an equilibrium between a cu(ii) aminoquinol and a cu(i) semiquinone, with the magnitude of the equilibrium constant being dependent upon the enzyme source. the i ...200616924556
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