Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
kinetics of methyl t-butyl ether cometabolism at low concentrations by pure cultures of butane-degrading bacteria.butane-oxidizing arthrobacter (atcc 27778) bacteria were shown to degrade low concentrations of methyl t-butyl ether (mtbe; range, 100 to 800 microg/liter) with an apparent half-saturation concentration (k(s)) of 2.14 mg/liter and a maximum substrate utilization rate (k(c)) of 0.43 mg/mg of total suspended solids per day. arthrobacter bacteria demonstrated mtbe degradation activity when grown on butane but not when grown on glucose, butanol, or tryptose phosphate broth. the presence of butane, t ...200111319100
neuraminidase from a bacterial source enhances both hiv-1-mediated syncytium formation and the virus binding/entry process.neuraminidases, also termed sialidases, which catalyze the removal of sialic acid residues from various glycoconjugates, have been previously reported to modulate hiv-1 replication. given that some of the known opportunistic microbes found in patients infected with hiv-1 harbor neuraminidase (na) activity, we speculated that pathogen-derived na might be envisaged as an important factor in the pathogenesis of this retroviral infection. in the present study, we have monitored the putative modulati ...200111352665
biological elimination of h2s and nh3 from wastegases by biofilter packed with immobilized heterotrophic bacteria.biotreatment of various ratios of h2s and nh3 gas mixtures was studied using the biofilters, packed with co-immobilized cells (arthrobacter oxydans ch8 for nh3 and pseudomonas putida ch11 for h2s). extensive tests to determine removal characteristics, removal efficiency, removal kinetics, and pressure drops of the biofilters were performed. to estimate the largest allowable inlet concentration, a prediction model was also employed. greater than 95%, and 90% removal efficiencies were observed for ...200111368219
isolation and characterisation of new gram-negative and gram-positive atrazine degrading bacteria from different french soils.the capacity of 12 soils to degrade atrazine was studied in laboratory incubations using radiolabelled atrazine. eight soils showed enhanced degradation of this compound. twenty-five bacterial strains able to degrade atrazine were isolated by an enrichment method from 10 of these soils. these soils were chosen for their wide range of physico-chemical characteristics. their history of treatment with atrazine was also variable. the genetic diversity of atrazine degraders was determined by amplifie ...200111451526
degradation of substituted phenylurea herbicides by arthrobacter globiformis strain d47 and characterization of a plasmid-associated hydrolase gene, puha.arthrobacter globiformis d47 was shown to degrade a range of substituted phenylurea herbicides in soil. this strain contained two plasmids of approximately 47 kb (phrim620) and 34 kb (phrim621). plasmid-curing experiments produced plasmid-free strains as well as strains containing either the 47- or the 34-kb plasmid. the strains were tested for their ability to degrade diuron, which demonstrated that the degradative genes were located on the 47-kb plasmid. studies on the growth of these strains ...200111319111
complete denitration of nitroglycerin by bacteria isolated from a washwater soakaway.four axenic bacterial species capable of biodegrading nitroglycerin (glycerol trinitrate [gtn]) were isolated from soil samples taken from a washwater soakaway at a disused gtn manufacturing plant. the isolates were identified by 16s rrna gene sequence homology as pseudomonas putida, an arthrobacter species, a klebsiella species, and a rhodococcus species. each of the isolates utilized gtn as its sole nitrogen source and removed nitro groups sequentially from gtn to produce glycerol dinitrates a ...200111375172
organization of the multiple coenzymes and subunits and role of the covalent flavin link in the complex heterotetrameric sarcosine oxidase.heterotetrameric (alphabetagammadelta) sarcosine oxidase from corynebacterium sp. p-1 (ctsox) contains noncovalently bound fad and nad(+) and covalently bound fmn, attached to beta(his173). the beta(his173asn) mutant is expressed as a catalytically inactive, labile heterotetramer. the beta and delta subunits are lost during mutant enzyme purification, which yields a stable alphagamma complex. addition of stabilizing agents prevents loss of the delta but not the beta subunit. the covalent flavin ...200111330998
[bacteria--degraders of polycyclic aromatic hydrocarbons, isolated from soil and bottom sediments in salt-mining areas].fifteen bacterial strains capable of utilizing naphthalene, phenanthrene, and biphenyl as the sole sources of carbon and energy were isolated from soils and bottom sediments contaminated with waste products generated by chemical and salt producing plants. based on cultural, morphological, and chemotaxonomic characteristics, ten of these strains were identified as belonging to the genera rhodococcus, arthrobacter, bacillus, and pseudomonas. all ten strains were found to be halotolerant bacteria c ...200111338839
tryptophan-216 is essential for the transglycosylation activity of endo-beta-n-acetylglucosaminidase a.endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) has a high level of transglycosylation activity. to determine which amino acids are involved in this activity, we employed deletion analysis, as well as random and site-directed mutagenesis. using pcr random mutagenesis, 11 mutants with greatly decreased levels of enzyme activity were isolated. six catalytically essential amino acids were identified by site-directed mutagenesis. mutants e173g, e175q, d206g, and d270n had ...200111341779
enzyme activity determination on macromolecular substrates by isothermal titration calorimetry: application to mesophilic and psychrophilic chitinases.isothermal titration calorimetry has been applied to the determination of the kinetic parameters of chitinases (ec 3.2.1.14) by monitoring the heat released during the hydrolysis of chitin glycosidic bonds. experiments were carried out using two different macromolecular substrates: a soluble polymer of n-acetylglucosamine and the insoluble chitin from crab shells. different experimental temperatures were used in order to compare the thermodependence of the activity of two chitinases from the psy ...200111342059
high-cell-density fermentation for production of l-n-carbamoylase using an expression system based on the escherichia coli rhabad promoter.a high-cell-density fed-batch fermentation for the production of heterologous proteins in escherichia coli was developed using the positively regulated escherichia coli rhabad promoter. the expression system was improved by reducing of the amount of expensive l-rhamnose necessary for induction of the rhamnose promoter and by increasing the vector stability. consumption of the inducer l-rhamnose was inhibited by inactivation of l-rhamnulose kinase encoding gene rhab of escherichia coli w3110, res ...200111255157
streamlined beta-galactosidase assay for analysis of recombinant yeast response to estrogens.here, we describe a rapid, convenient, and quantitative beta-galactosidase assay in liquid culture of recombinant yeast that expresses the estrogen receptor. this assay allows large-scale screening of chemicals (more than 600 samples/day) for the evaluation of their direct estrogenic potency and accurate determination of their ec50 with minimal manipulations. the assay, which is based on digestion of the yeast cell wall by lyticase (zymolase), a beta-glucanase isolated from arthrobacter luteus, ...200111355334
isolation and characterization of is1409, an insertion element of 4-chlorobenzoate-degrading arthrobacter sp. strain tm1, and development of a system for transposon mutagenesis.a new insertion element of 1,449 bp with 25-bp perfect terminal repeats, designated is1409, was identified in the chromosome of 4-chlorobenzoate-degrading arthrobacter sp. strain tm1 ncib12013. upon insertion, is1409 causes a target duplication of 8 bp. is1409 carries only a single open reading frame of 435 codons encoding the transposase tnpa. both tnpa and the overall organization of is1409 are highly similar to those of some related insertion elements of the isl3 group (j. mahillon and m. cha ...200111371537
molecular cloning and expression of endo-beta-n-acetylglucosaminidase d, which acts on the core structure of complex type asparagine-linked oligosaccharides.endo-beta-n-acetylglucosaminidase d (endo d) produced by streptococcus pneumoniae cleaves the di-n-acetylchitobiose structure in asparagine-linked oligosaccharides. the enzyme generally acts on complex type oligosaccharides after removal of external sugars by neuraminidase, beta-galactosidase, and beta-n-acetylglucosaminidase. we cloned the gene encoding the enzyme and expressed it as a periplasm enzyme in escherichia coli. the first 37 amino acids in the predicted sequence are removed in the ma ...200111388907
diversity and seasonal fluctuations of the dominant members of the bacterial soil community in a wheat field as determined by cultivation and molecular methods.there is a paucity of knowledge on microbial community diversity and naturally occurring seasonal variations in agricultural soil. for this purpose the soil microbial community of a wheat field on an experimental farm in the netherlands was studied by using both cultivation-based and molecule-based methods. samples were taken in the different seasons over a 1-year period. fatty acid-based typing of bacterial isolates obtained via plating revealed a diverse community of mainly gram-positive bacte ...200111319113
organization of the genes involved in dimethylglycine and sarcosine degradation in arthrobacter spp.: implications for glycine betaine catabolism.the nucleotide sequences of two cloned dna fragments containing the structural genes of heterotetrameric sarcosine oxidase (soxbdag) and dimethylglycine dehydrogenase (dmg) from arthrobater spp. 1-in and arthrobacter globiformis, respectively, have been determined. open reading frames were identified in the soxbdag operon corresponding to the four subunits of heterotetrameric sarcosine oxidase by comparison with the n-terminal amino-acid sequences and the subunit relative molecular masses of the ...200111422368
the interaction of protozoa with their potential prey bacteria in the rhizosphere.extensive colonization of the rhizosphere by beneficial bacteria is desirable but it is not yet clear whether the feeding patterns of protozoa exert any ecological impact on the competence of bacteria in the rhizosphere. to determine whether the successful colonization of the rhizosphere by bacteria can be explained by inherent abilities of the bacteria to resist predation, six bacteria categorized as poor, mediocre or good rhizosphere colonists were tested. the populations of protozoa in the rh ...200111411840
[formation of microbial populations on the surface of protective coatings].formation of microbial cenosis on the surface of polyethylene-, polyurethane- and oil-bitumen-based protective coatings was studied in dynamics during 1, 3, 7, 14 and 21 days. it has been shown that the biofilm was formed on the protective materials during 14 days and consisted of ammonifying, denitrifying, hydrocarbon-oxidizing and sulphate-reducing bacteria referred to pseudomonas, arthrobacter, bacillus and kesulfovibrio genera. the bacteria which form the biofilm on coatings possess high den ...200111558243
optimization of the immobilization parameters and operational stability of immobilized hydantoinase and l-n-carbamoylase from arthrobacter aurescens for the production of optically pure l-amino acids.2the immobilization parameters were optimized for the hydantoinase and the l-n-carbamoylase from arthrobacter aurescens dsm 3747 or 3745, respectively. to optimize activity yields and specific activities for the immobilization to eupergit c, eupergit c 250 l, and eah-sepharose wild-type, recombinant and genetically modified ('tagged') enzymes were investigated concerning the influence of the protein concentration, the kind of support and the immobilization method. for both enzymes, the use of th ...200111339957
feasibility of fluidized-bed bioreactor for remediating waste gas containing h2s or nh3.pseudomonas putida for h2s and arthrobacter oxydans for nh3 were immobilized with ca-alginate and packed inside glass columns to form fluidized-bed bioreactors. the feasibility of the lab-scale bioreactor for the treatment of h2s or nh3 was examined. phosphate salt, being added to the nutrient solution as buffer solution, may chelate with ca2+ in the ca-alginate beads, resulting in the disintegration of gel structure. when the buffer capacity of the phosphate solution was over the critical point ...200111413835
occurrence of oligosialic acids on integrin alpha 5 subunit and their involvement in cell adhesion to fibronectin.integrin alpha(5)beta(1), a major fibronectin receptor, functions in a wide variety of biological phenomena. we have found that alpha 2-8-linked oligosialic acids with 5 < or = degree of polymerization (dp) < or = 7 occur on integrin alpha(5) subunit of the human melanoma cell line g361. the integrin alpha(5) subunit immunoprecipitated with anti-integrin alpha(5) antibody reacted with the monoclonal antibody 12e3, which recognizes oligo/polysialic acid with dp > or = 5 but not with the polyclona ...200111418585
dual-bioaugmentation strategy to enhance remediation of cocontaminated soil.although metals are thought to inhibit the ability of microorganisms to degrade organic pollutants, several microbial mechanisms of resistance to metal are known to exist. this study examined the potential of cadmium-resistant microorganisms to reduce soluble cadmium levels to enhance degradation of 2,4-dichlorophenoxyacetic acid (2,4-d) under conditions of cocontamination. four cadmium-resistant soil microorganisms were examined in this study. resistant up to a cadmium concentration of 275 micr ...200111425743
modular structure, local flexibility and cold-activity of a novel chitobiase from a psychrophilic antarctic bacterium.the gene archb encoding for the cell-bound chitobiase from the antarctic gram-positive bacterium arthrobacter sp. tad20 was cloned and expressed in escherichia coli in a soluble form. the mature chitobiase archb possesses four functionally independent domains: a catalytic domain stabilized by ca(2+), a galactose-binding domain and an immunoglobulin-like domain followed by a cell-wall anchorage signal, typical of cell-surface proteins from gram-positive bacteria. binding of saccharides was analyz ...200111428890
bioremediation of an area contaminated by a fuel spill.in order to decontaminate a large area of restricted access contaminated by a fuel spill, laboratory and field studies were developed in two steps: (a) monitoring of the laboratory experiment on bacterial growth under aerobic and anaerobic conditions with and without addition of nutrients; and (b) use of the best conditions obtained in (a) for the decontamination of the soil. a hydraulic barrier was installed both to clean the aquifer and to avoid migration of hydrocarbons as a consequence of th ...200111432263
purification and characterization of carbaryl hydrolase from arthrobacter sp. rc100.a carbaryl hydrolase was purified to homogeneity from arthrobacter sp. strain rc100 by protamine sulfate treatment, ammonium sulfate precipitation, and hydrophobic, anion-exchange, and gel filtration chromatographies. the native enzyme had a molecular mass of 100 kda and was composed of two identical subunits with molecular masses of 51 kda. the hydrolase activity was strongly inhibited by difp, pmsf, hg(2+) and paraoxon but not by edta. the optimum ph and temperature for the enzyme activity wer ...200111445174
modeling of copper biosorption by arthrobacter sp. in a uf/mf membrane reactor.copper biosorption by arthrobacter sp. has been studied in this work. the process has been realized inside of a ultrafiltration/microfiltration (uf/mf) reactor in order to confine cells. a mathematical model has been developed that is able to predict experimental data under different operating conditions. the model takes into account different phenomena, which might occur during the process, such as a dependence of equilibrium parameters on ph, a partial cell disruption, and a change in the memb ...200111478261
alpha 2,3-sialylation of terminal galnac beta 1-3gal determinants by st3gal ii reveals the multifunctionality of the enzyme. the resulting neu5ac alpha 2-3galnac linkage is resistant to sialidases from newcastle disease virus and streptococcus pneumoniae.enzymatic alpha 2,3-sialylation of galnac has not been described previously, although some glycoconjugates containing alpha 2,3-sialylated galnac residues have been reported. in the present experiments, recombinant soluble alpha 2,3-sialyltransferase st3gal ii efficiently sialylated the x(2) pentasaccharide galnac beta 1-3gal beta 1-4glcnac beta 1-3gal beta 1-4glc, globo-n-tetraose galnac beta 1-3gal alpha 1-4gal beta 1-4glc, and the disaccharide galnac beta 1-3gal in vitro. the purified product ...200111479313
isolation of poly(3-hydroxybutyrate) (phb)-degrading microorganisms and characterization of phb-depolymerase from arthrobacter sp. strain w6.microbial degraders of poly(3-hydroxybutyrate) (phb) were isolated from soil. arthrobacter sp. strain w6 used not only phb as a carbon source, but also phas such as poly(3-hydroxybutyrate-co-[5%]3-hydroxyvalerate), poly(3-hydroxybutyrate-co-[14%]3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-[22%]3-hydroxyvalerate). phb-depolymerase was purified to homogeneity from the culture broth of arthrobacter sp. strain w6 by a procedure involving deae- and butyl-toyopearl column chromatographies. the m ...200111440137
construction, overexpression, and purification of arthrobacter globiformis amine oxidase-strep-tag ii fusion protein.the copper-containing amine oxidase from arthrobacter globiformis has been expressed and purified as a fusion protein with a c-terminal strep-tag ii peptide. this tag facilitates the rapid purification of the enzyme on a large scale using the streptactin poros medium. for example, we have demonstrated that 50 mg of protein can be obtained in 2 days from 2 l of escherichia coli. the purified fusion protein displays turnover and spectroscopic properties that are essentially identical to those of t ...200111483008
a novel disaccharide substrate having 1,2-oxazoline moiety for detection of transglycosylating activity of endoglycosidases.a disaccharide substrate of manbeta1-4glcnac-oxazoline 2 was designed and synthesized as a novel probe for detection of the transglycosylating activity of endoglycosidases. a regio- and stereoselective transglycosylation reaction of 2 to glcnacbeta1-o-pnp or dns-asn(glcnac)-oh catalyzed by endo-beta-n-acetylglucosaminidase from mucor hiemalis (endo-m) and endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) has been demonstrated for the first time, resulting in the core tri ...200111514092
interactions between yeasts and bacteria in the smear surface-ripened cheeses.in the initial phase of ripening, the microflora of bacterial smear surface-ripened cheeses such as limburger, taleggio, brick, münster and saint-paulin and that of surface mould-ripened cheeses such as camembert and brie may be similar, but at the end of the ripening, bacteria such as brevibacterium spp., arthrobacter spp., micrococcus spp., corynebacterium spp. and moulds such as penicillium camemberti are, respectively, the dominant microorganisms. yeasts such as candida spp., cryptococcus sp ...200111589547
gene cluster on pao1 of arthrobacter nicotinovorans involved in degradation of the plant alkaloid nicotine: cloning, purification, and characterization of 2,6-dihydroxypyridine 3-hydroxylase.a 27,690-bp gene cluster involved in the degradation of the plant alkaloid nicotine was characterized from the plasmid pao1 of arthrobacter nicotinovorans. the genes of the heterotrimeric, molybdopterin cofactor (moco)-, flavin adenine dinucleotide (fad)-, and [fe-s] cluster-dependent 6-hydroxypseudooxynicotine (ketone) dehydrogenase (kdh) were identified within this cluster. the gene of the large moco subunit of kdh was located 4,266 bp from the fad and [fe-s] cluster subunit genes. deduced fun ...200111514508
molecular and enzymatic characterization of a levan fructotransferase from microbacterium sp. al-210.microbacterium sp. al-210 producing a novel levan fructotransferase (lftase) was screened from soil samples. the lftase was purified to homogeneity by (nh4)2so4 fractionation, column chromatography on resource q, and superdex 200hr. the molecular weight of the purified enzyme was estimated to be approximately 46 kda by both sds-page and gel filtration, and the enzyme's isoelectric point was ph 4.8. the major product produced from the levan hydrolysis by the enzyme reaction was identified by atmo ...200111522362
effects of lipids on n-alkane attenuation in media supporting oil-utilizing microorganisms from the oily arabian gulf coasts.the arabian gulf is one of the most extensively oil-polluted areas of the world. the major objectives of this work were to study whether hydrocarbon-utilizing microorganisms indigenous to that area would readily accumulate added lipids, and whether this might affect their hydrocarbon consumption potential. two prokaryotes, arthrobacter nicotianae kcc b35 and the unidentified organisms kcc b6, as well as one eukaryote, candida parapsilosis kcc y1, were selected for this study. biomass samples of ...200111430415
trehalose-producing operon treyz from arthrobacter ramosus s34.arthrobacter ramosus s34, which produces trehalose from maltooligosaccharide, was isolated. a trehalose-producing operon, treyz, was cloned from the genome. expression experiments with trey and trez confirmed that they coded malto-oligosyltrehalose synthase and malto-oligosyltrehalose trehalohydrolase, respectively. the amino acid sequence of trey from a. ramosus s34 and that from arthrobacter sp. q36 did not show high identity, nor did those of trez.200111471747
isolation and characterization of psychotrophic bacteria from oil-reservoir water and oil sands.four psychrotrophic strains, which grew at 4 degrees c but not at 37 degrees c, were isolated from japanese oil-reservoir water (strains sib1, sic1, sis1) and canadian oil sands (strain cab1). strains sib1, sis1, and cab1 had a maximum growth rate at 20 degrees c and grew to the highest cell densities at the cultivation temperature of 0-4 degrees c. strain sis1 was capable of growing even at -5 degrees c. the growth profile of strain sic1 was rather similar to that of a mesophilic bacterium. str ...200111525631
optimization of protease activity of alkaliphilic bacteria isolated from an alkaline lake in india.alkaliphilic bacteria belonging to the genera bacillus, staphylococcus, micrococcus, pseudomonas and arthrobacter isolated from sediment samples of the alkaline lonar lake situated in the buldhana district of maharashtra state, india, were studied for the production of protease activity. among the 54 isolates obtained, arthrobacter ramosus and bacillus alcalophilus exhibited high protease activity using soyacake as a sole source of carbon and nitrogen. protease activity was optimum at 1% initial ...200212146649
biomineralization of an organophosphorus pesticide, monocrotophos, by soil bacteria.to study biomineralization of monocrotophos (mcp) and identify the metabolites formed during biodegradation.200212147070
towards the development of selective amine oxidase inhibitors. mechanism-based inhibition of six copper containing amine oxidases.four substrate analogs, 4-(2-naphthyloxy)-2-butyn-1-amine (1), 1,4-diamino-2-chloro-2-butene (2), 1,6-diamino-2,4-hexadiyne (3), and 2-chloro-5-phthalimidopentylamine (4) have been tested as inhibitors against mammalian, plant, bacterial, and fungal copper-containing amine oxidases: bovine plasma amine oxidase (bpao), equine plasma amine oxidase (epao), pea seedling amine oxidase (psao), arthrobacter globiformis amine oxidase (agao), escherichia coli amine oxidase (ecao), and pichia pastoris lys ...200212153561
tolerance of bacteria to organic solvents.organic-solvent-tolerant bacteria are a relatively novel group of extremophilic microorganisms. they overcome the toxic and destructive effects of organic solvents due to the presence of various adaptive mechanisms. extensive studies done on the toluene tolerance of certain pseudomonas strains have led to an understanding of the mechanisms of organic solvent tolerance involving novel adaptations such as the toluene efflux pumps, cis-trans isomerisation of membrane fatty acids, rapid membrane rep ...200212160316
conversion of liposomal 4-androsten-3,17-dione by a. simplex immobilized cells in calcium pectate.arthrobacter simplex atcc 6946 free and immobilized cells were assayed for their ability to convert 4-androsten-3,17-dione (ad) to 1,4-androstadien-3,17-dione (add) in aqueous and liposomal media. bioconversions were carried out in a 100 ml flask containing 25 ml of ad liposomal or aqueous medium for 3h, and ad concentrations ranging from 0.3 to 1.0 mm were tested. ad/add ratios in samples were determined by hplc. biotransformation of substrate entrapped in multilamellar vesicles (mlv) was demon ...200211867272
enzymes of dimethylsulfone metabolism and the phylogenetic characterization of the facultative methylotrophs arthrobacter sulfonivorans sp. nov., arthrobacter methylotrophus sp. nov., and hyphomicrobium sulfonivorans sp. nov.novel methylotrophic arthrobacter and hyphomicrobium species are described. constitutive membrane-associated dimethylsulfone- and dimethylsulfoxide-reductases were found in arthrobacter methylotrophus strain tga and hyphomicrobium sulfonivorans strain s1. enzyme activities increased during growth with dimethylsulfone or dimethylsulfoxide, respectively, and different ratios of activity with different growth substrates indicated that they are separate enzymes. sds-page showed some membrane-associa ...200211807567
[the role of low-molecular-weight nitrogen compounds in the osmotolerance of rhodococcus erythropolis and arthrobacter globiformis].investigations showed that rhodococcus erythropolis e-15 and arthrobacter globiformis 2f cells respond to osmotic shock by increasing the synthesis of free amino acids, primarily glutamic acid (80% of the intracellular free amino acid pool). the osmoprotective role of glutamic acid follows from its beneficial effect on the growth of bacteria in high-salinity media. it was found that the addition of this amino acid to the growth medium at a concentration of 2 mm shortened the lag phase and increa ...200212024813
the trans-anethole degradation pathway in an arthrobacter sp.a bacterial strain (ta13) capable of utilizing t-anethole as the sole carbon source was isolated from soil. the strain was identified as arthrobacter aurescens based on its 16 s rrna gene sequence. key steps of the degradation pathway of t-anethole were identified by the use of t-anethole-blocked mutants and specific inducible enzymatic activities. in addition to t-anethole, strain ta13 is capable of utilizing anisic acid, anisaldehyde, and anisic alcohol as the sole carbon source. t-anethole-bl ...200211805095
biotransformation of phenylurea herbicides by a soil bacterial strain, arthrobacter sp. n2: structure, ecotoxicity and fate of diuron metabolite with soil fungi.in order to assess the influence of the aromatic substitution on the ability of a soil bacterial strain, arthrobacter sp. n2, to degrade phenylurea herbicides, biotransformation assays were performed in mineral medium with resting cells of this soil bacterial strain on three phenylurea herbicides (diuron, chlorotoluron and isoproturon). each herbicide considered, led to the formation of only one metabolite detected by hplc analysis. after isolation, the metabolites were identified by nmr and ms, ...200211838430
rates of oxygen and hydrogen exchange as indicators of tpq cofactor orientation in amine oxidases.this study presents the first detailed examination by resonance raman (rr) spectroscopy of the rates of solvent exchange for the c5 and c3 positions of the tpq cofactor in several wild-type copper-containing amine oxidases and mutants of the amine oxidase from hansenula polymorpha (hpao). on the basis of crystal structure analysis and differing rates of c5 [double bond] o and c3 [bond] h exchange within the enzyme systems, but equally rapid rates of c5 [double bond] o and c3 [bond] h exchange in ...200211781110
utilization of xylitol dehydrogenase in a combined microbial/enzymatic process for production of xylitol from d-glucose.the production of xylitol from d-glucose occurs through a three-step process in which d-arabitol and d-xylulose are formed as the first and second intermediate product, respectively, and both are obtained via microbial bioconversion reactions. catalytic hydrogenation of d-xylulose yields xylitol; however, it is contaminated with d-arabitol. the aim of this study was to increase the stereoselectivity of the d-xylulose reduction step by using enzymatic catalysis. recombinant xylitol dehydrogenase ...200212018283
arthrobacter roseus sp. nov., a psychrophilic bacterium isolated from an antarctic cyanobacterial mat sample.strain cms 90rt, a red-pigmented bacterium, was isolated from a cyanobacterial mat sample from a pond located in mcmurdo, antarctica. based on its chemotaxonomic and phylogenetic properties, strain cms 90r(t) was identified as a member of group i of arthrobacter. it shared 16s rdna similarity of 98% with arthrobacter oxydans atcc 14358t and arthrobacter polychromogenes atcc 15216t, while dna-dna similarities determined for these three organisms were less than 70%. it also differed from all 17 re ...200212054218
capillary electrophoresis of cr(vi) reducer arthrobacter oxydans.rapid and effective separation of bacteria arthrobacter oxydans was performed using capillary electrophoresis. for optimal separation of bacteria the influence of buffer concentration, ph and applied voltage were studied. it was found that the most appropriate conditions for electrophoretic mobility measurements are as follows: applied voltage 6-14 kv; buffer concentration 5-10 mm ph 6-8. at the stationary phase of growth there are always two main heterogeneous peaks. they are connected with the ...200212210506
cultivation-dependent characterization of bacterial diversity from british columbia forest soils subjected to disturbance.bacteria from forest surface organic matter and mineral soil horizons were cultivated using four methods and characterized by fatty acid methyl ester (fame) analysis. soil samples from a british columbia ministry of forests long-term soil productivity (ltsp) installation were collected during winter and summer from two disturbance treatments (whole-tree harvesting with no soil compaction (plot n) and whole-tree harvesting plus complete surface organic matter removal with heavy soil compaction (p ...200212224563
isolation of arthrobacter strains on the basis of their cystite formation. 200212469299
electron spin resonance study of copper biosorption by bacteria.the biosorption of copper by bacteria was studied by using esr spectroscopy. among bacteria tested, arthrobacter nicotianae has the most excellent ability to sorb copper. the biosorption of copper by arthrobacter cells was so rapid, affected by the solution ph, and obeys the langmuir adsorption equilibrium. the electron spin resonance (esr) spectra of cu(ii) in bacterial cells are axial type, having a major absorption to higher field at gperpendicular and lesser absorption to lower field at gpar ...200212092584
the structure of l-hydantoinase from arthobacter aurescens leads to an understanding of dihydropyrimidinase substrate and enantio specificity.l-hydantoinase from arthrobacter aurescens (l-hyd) is a member of the dihydropyrimidinases which in turn belong to the cyclic amidases. dihydropyrimidinases catalyze the reversible hydrolytic ring opening of dihydropyrimidines as the second step in the catabolism of pyrimidines. in biotechnology, their hydroloytic activity on five-membered cyclic diamides (hydantoins) is used in the enantio-specific production of amino acids from racemic hydantoins. l-hyd differs from most of the other dihydropy ...200212093275
purification and characterization of aminobutyraldehyde dehydrogenase from arthrobacter sp. tmp-1.aminobutyraldehyde dehydrogenase was purified to essentially homogeneity from putrescine-grown cells of arthrobacter sp. tmp-1. the molecular weights of the enzyme and its subunit were 201,000 and 51,000, respectively, suggesting that the enzyme is a tetramer of identical subunits. the apparent michaelis constants (k(m)) for 4-aminobutyraldehyde, 3-aminopropionaldehyde and 4-guanidinobutyraldehyde were approximately 65, 150, and 85 microm, respectively. linear fatty aldehydes also tested were le ...200212186751
aari, a restriction endonuclease from arthrobacter aurescens ss2-322, which recognizes the novel non-palindromic sequence 5'-cacctgc(n)4/8-3'.a new type ii restriction endonuclease aari has been isolated from arthrobacter aurescens ss2-322. aari recognizes the non-palindromic heptanucleotide sequence 5'-cacctgc(n)4/8-3' and makes a staggered cut at the fourth and eighth bases downstream of the target duplex producing a four base 5'-protruding end. aari activity is stimulated by oligodeoxyribonucleotide duplexes containing an enzyme-specific recognition sequence.200212409482
arthrobacter aurescens tc1 metabolizes diverse s-triazine ring compounds.arthrobacter aurescens strain tc1 was isolated without enrichment by plating atrazine-contaminated soil directly onto atrazine-clearing plates. a. aurescens tc1 grew in liquid medium with atrazine as the sole source of nitrogen, carbon, and energy, consuming up to 3,000 mg of atrazine per liter. a. aurescens tc1 is metabolically diverse and grew on a wider range of s-triazine compounds than any bacterium previously characterized. the 23 s-triazine substrates serving as the sole nitrogen source i ...200212450818
simultaneous horizontal gene transfer of a gene coding for ribosomal protein l27 and operational genes in arthrobacter sp.phylogenetic analysis of bacterial l27 ribosomal proteins showed that, against taxonomy, the l27 protein from the actinobacteria arthrobacter sp. clusters with protein sequences from the bacillus group. the l27 gene clusters in the arthrobacter sp. genome with six genes responsible for creatinine and sarcosine degradation. phylogenetic analyses of orthologue proteins encoded by three of these genes also showed a phylogenetic relationship with bacillus species. comparisons between the synonymous ...200212486522
exposure to airborne microorganisms and endotoxin in a potato processing plant.microbiological air sampling was performed in a big potato processing plant located in eastern poland. air samples for determination of concentrations of microorganisms, dust and endotoxin were collected at 6 sites in the division producing potato flakes and meal from dried potato pulp and at 2 sites in the division producing potato syrup from imported starch. the concentrations of total airborne microorganisms were within a range of 28.3-93.1 x 10(3) cfu/m(3). mesophilic bacteria were dominant ...200212498592
bioremediation of an industrial effluent containing monocrotophos.almost 30% of the precious agricultural output of india is lost owing to pest infestation. in india, pesticide consumption for protecting crops is about 3% of the total world consumption. monocrotophos (mcp), an organophosphorus insecticide, is widely used to control insects on crops. being readily water soluble and highly toxic, its removal from wastewater generated during manufacture becomes inevitable. bioremediation of wastewater containing mcp by arthrobacter atrocyaneus, bacillus megateriu ...200212232665
mechanistic aspects of the covalent flavoprotein dimethylglycine oxidase of arthrobacter globiformis studied by stopped-flow spectrophotometry.dimethylglycine oxidase (dmgo) is a covalent flavoenzyme from arthrobacter globiformis that catalyzes the oxidative demethylation of dimethylglycine to yield sarcosine, formaldehyde, and hydrogen peroxide. stopped-flow and steady-state kinetic studies have been used to study the reductive and oxidative half-reactions using dimethylglycine and o2 as substrates. the reductive half-reaction is triphasic. the rate of the fast phase is dependent on substrate concentration, involves flavin reduction, ...200211926836
x-ray snapshots of quinone cofactor biogenesis in bacterial copper amine oxidase.the quinone cofactor tpq in copper amine oxidase is generated by posttranslational modification of an active site tyrosine residue. using x-ray crystallography, we have probed the copper-dependent autooxidation process of tpq in the enzyme from arthrobacter globiformis. apo enzyme crystals were anaerobically soaked with copper; the structure determined from this crystal provides a view of the initial state: the unmodified tyrosine coordinated to the bound copper. exposure of the copper-bound cry ...200212134140
arthrobacter nasiphocae sp. nov., from the common seal (phoca vitulina).an unknown gram-positive, catalase-positive, strictly aerobic, rod-shaped bacterium was isolated from the nasal cavities of two common seals. chemical analysis revealed the presence in the bacterium of a hitherto unknown cell-wall murein [type: l-lys-l-ala2-gly(2-3)-l-ala (gly)]. comparative 16s rrna gene sequencing showed that the unidentified rod was related to the arthrobacter group of organisms, although sequence divergence values of >3% from established members of this genus indicated that ...200211931170
[bacterial succession on n-alkanes under the conditions of sulfate reduction].the dynamics of species composition of a hydrocarbon-oxidizing bacteriocenosis of a ground suspension of mozhaisk reservoir has been studied. the bacteriocenosis was undergoing development in a paraffin film (model association composed of sulfate-reducing bacteria and hydrocarbon-oxidizing bacteria). the type of bacterial succession did not depend on the depth, from which ground samples were collected. two microbial species (pseudomonas sp. and arthrobacter globiformis) were absolutely dominant. ...200211962208
response of endophytic bacterial communities in potato plants to infection with erwinia carotovora subsp. atroseptica.the term endophyte refers to interior colonization of plants by microorganisms that do not have pathogenic effects on their hosts, and various endophytes have been found to play important roles in plant vitality. in this study, cultivation-independent terminal restriction fragment length polymorphism analysis of 16s ribosomal dna directly amplified from plant tissue dna was used in combination with molecular characterization of isolates to examine the influence of plant stress, achieved by infec ...200211976096
impact of protozoan grazing on bacterial community structure in soil microcosms.the influence of grazing by a mixed assemblage of soil protozoa (seven flagellates and one amoeba) on bacterial community structure was studied in soil microcosms amended with a particulate resource (sterile wheat roots) or a soluble resource (a solution of various organic compounds). sterilized soil was reinoculated with mixed soil bacteria (obtained by filtering and dilution) or with bacteria and protozoa. denaturing gradient gel electrophoresis (dgge) of pcr amplifications of 16s rrna gene fr ...200212450833
isolation, characterization and diuron transformation capacities of a bacterial strain arthrobacter sp. n2.a bacterial strain able to transform diuron was isolated from a soil by enrichment procedures. strain isolation was realized by plating on minimal-agarose medium spread with this herbicide and selecting the colonies surrounded by a clear thin halo. one strain was characterized and identified as an arthrobacter sp. it metabolized diuron and the final transformation product, 3,4-dichloroaniline, was produced in stoichiometric amounts. the transformation of diuron at different concentrations was mo ...200211838431
response of furniture factory workers to work-related airborne allergens.the aim of this work was to determine the reactivity of furniture factory workers to microbial allergens associated with wood dust. allergological examinations by skin and precipitin tests were performed in 48 workers employed in a factory producing furniture from fibreboards and chipboards, and in 32 healthy urban dwellers not exposed to organic dusts (referents). the skin test was performed by the intradermal method with the saline extracts of the cultures of 3 microbial species (rahnella sp., ...200212088404
[studies on hydantoinase producing conditions of arthrobacter k1108].the hydantoinase-producing conditions from strain arthrobacter k1108 were investigated. it is shown that the hydantoinase in the strain is intracellular and inducible. its optimal inducer is 5-benzylhydantoin, while 5-indolylmethylhydantoin and 5-phenylhydantoin cannot induce the production of hydantoinase in k1108. a gratuitous inducer was designed, with which the hydantoinase production is 343% as much as that with 5-benzylhydantoin. the media for culturing the bacteria were screened and optim ...200212557399
[the solubilization of four insoluble phosphates by some microorganisms].four insoluble phosphates of ferric phosphate (fe-p), aluminum phosphate (al-p), fluorapatite (fap) and rock phosphate (rp) were used as a sole phosphorus resource for some phosphate-solubilizing microorganisms. it was found that there was significant difference in solubilizing these phosphates by the tested isolates. the fungi normally were more powerful than the bacteria in dissolving the phsophates. the microorganisms generally solubilized more phosphate when supplied with no3- than with nh4+ ...200212557403
citricoccus muralis gen. nov., sp. nov., a novel actinobacterium isolated from a medieval wall painting.a gram-positive, aerobic, spherical actinobacterium, designated strain 4-0(t), was isolated from a medieval wall painting and characterized to determine its taxonomic position. the peptidoglycan of strain 4-0(t) was of type a4alpha, with lysine as the diagnostic cell wall diamino acid and an interpeptide bridge of lys-gly-glu. its quinone system contained predominantly mk-9(h2) (64%) and its polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, four ...200212508874
[mercury-resistant bacteria from permafrost sediments and prospects for their use in comparative studies of mercury resistance determinants].mercury-resistant bacteria were isolated from permafrost sediments of kolyma lowland and canada existing over five thousand to two million years. their content was shown to vary within the range 0.001-2.9% and to depend on the amount of mercury in sampling sites (coefficient of correlation 0.75). a collection of mercury-resistant bacterial strains was created. in this collection, various representatives of both gram-positive bacteria (bacillus, exiguobacterium, micrococcus, arthrobacter) and gra ...200212500685
novel reversible indole-3-carboxylate decarboxylase catalyzing nonoxidative decarboxylation.after enrichment culture with indole-3-carboxylate in static culture, a novel reversible decarboxylase, indole-3-carboxylate decarboxylase, was found in arthrobacter nicotianae fi1612 and several molds. the enzyme reaction was examined in resting-cell reactions with a. nicotianae fi1612. the enzyme activity was induced specifically by indole-3-carboxylate, but not by indole. the indole-3-carboxylate decarboxylase of a. nicotianae fi1612 catalyzed the nonoxidative decarboxylation of indole-3-carb ...200212506977
[the existence of contamination in enzymes used for the isolation of aspergillus and candida species dna].molecular biological methods which are widely used in different fields, have been replaced with conventional diagnostic tests for the early diagnosis of invasive fungal infections, recently. polymerase chain reaction (pcr) is one of these methods, with high specificity and sensitivity, which is accepted throughout the world. however, the enzymes that are used for the isolation of target dna, may be contaminated with the gene sequences of some other fungal species in the preparation steps and may ...200212652873
[microbial destruction of harmful organic contaminants inherent to atmosphere of living space].the investigation into the microbial destruction of harmful organic contaminants in the air of habitable rooms was performed with the assumption that microorganisms have labile metabolism and synthesize inducible enzymes involved in transformation of organics compounds. based on our observations, methylobacterium d-08 and arthrobacter pastens are able to synthesize inducible enzymes and transform ethanol, acetic acid, acetone, and aldehyde. association of these microorganisms does not reveal acu ...200212572127
transgenics of an elite indica rice variety pusa basmati 1 harbouring the coda gene are highly tolerant to salt stress.transgenic lines of indica rice were generated by agrobacterium-mediated transformation with the choline oxidase ( coda) gene from arthrobacter globiformis. choline oxidase catalyses conversion of choline to glycine betaine. glycine betaine is known to provide tolerance against a variety of stresses. molecular analyses of seven independent transgenic lines as performed by southern, northern and western hybridization revealed integration and expression of the transgene as well as inheritance in t ...200212582870
studies on the effect of inoculation of activated sludge with bacteria actively degrading hydrocarbons on the biodegradation of petroleum products.eighteen strains of bacteria were isolated from activated sludge purifying petroleum-refining wastewaters. these strains were plated on solidified mineral medium supplemented with oil fraction in concentration 1000 mg/l. four of the strains that grew best in the presence of oil were selected for further studies. the strains were identified based on bonde's scheme and microscopic observations. three of them belonged to the genus arthrobacter and one to the genus micrococcus. stationary cultures o ...200212588103
exposure to airborne microorganisms in furniture factories.microbiological air sampling was performed in 2 furniture factories located in eastern poland. in one factory furniture were made from fibreboards and chipboards while in the other from beech wood. it was found that the concentration of total microorganisms (bacteria + fungi) in the air of the facility using beech wood for furniture production (mean 10.7 x (3) cfu/m(3), range 3.3 27.5 x (3) cfu/m(3)) was significantly higher (p < 0.01) compared to microbial concentration in the facility using fi ...200212088403
transfer of high-mannose-type oligosaccharides to disaccharides by endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae.endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) has transglycosylation activity, and high-mannose-type oligosaccharides are transferred to suitable glycosides as acceptor substrates. the acceptor specificity of endo-a-catalyzed transglycosylation toward various disaccharides was investigated. to identify an effective acceptor for the transglycosylation by endo-a, the reaction was carried out using various disaccharides. endo-a transferred high-mannose-type oligosacchar ...200216233259
purification and properties of betaine aldehyde dehydrogenase with high affinity for nadp from arthrobacter globiformis.betaine aldehyde dehydrogenase from arthrobacter globiformis was purified to apparent homogeneity by ammonium sulfate fractionation, followed by ion-exchange, butyl-toyopearl and gel filtration chromatography. the enzyme was found to be a tetramer with identical 55 kda subunits. both nad+ and nadp+ could be used as a cofactor for the enzyme and michaelis constants (k(m) value) for nad+ and nadp+ were 1075 microm and 48 microm, respectively. the enzyme was highly specific for betaine aldehyde and ...200216233177
removal and recovery of uranyl ion using various microorganisms.the adsorption of uranyl ion by microorganisms was examined. among the 76 strains of 69 species tested (23 bacteria, 20 actinomycetes, 18 fungi, and 15 yeasts), high uranyl ion adsorption ability was exhibited by strains of the bacteria, arthrobacter nicotianae, bacillus subtilis, and micrococcus luteus. a. nicotianae cells, which showed the best performance, could adsorb about 698 mg uranyl ion (2.58 mmol) per gram dry wt. of microbial cells. the adsorption of uranyl ion was rapid, selective, a ...200216233264
plasmid localisation of atrazine-degrading genes in newly described chelatobacter and arthrobacter strains.abstract in a previous study, we isolated a collection of atrazine-degrading bacteria from various soils. the aim of this study was to localise the atrazine-degrading genes in these 25 atrazine-degrading strains. in the case of the gram-negative strains of chelatobacter heintzii, six to seven plasmids were observed. the atzabc and trzd genes were located on two or three plasmids with variable molecular masses. for the gram-positive strains of arthrobacter crystallopoietes, the atzbc genes were l ...200219709240
bacterial populations associated with mycelium of the arbuscular mycorrhizal fungus glomus intraradices.abstract the influences of the arbuscular mycorrhizal fungus glomus intraradices on the culturable aerobic-heterotrophic bacterial communities in the rhizosphere and hyphosphere of cucumber plants (cucumis satvius) were investigated. mycorrhizal and non-mycorrhizal plants were grown in compartmentalised growth units, each with a root compartment and two lateral root-free compartments. samples representing rhizosphere, root-free soil, root-free sand and washed sand extract were collected 52 days ...200219709247
impact of 4-chlorophenol contamination and/or inoculation with the 4-chlorophenol-degrading strain, arthrobacter chlorophenolicus a6l, on soil bacterial community structure.the 4-chlorophenol-degrading strain, arthrobacter chlorophenolicus a6l (chromosomally tagged with the firefly luciferase gene, luc) was inoculated into 4-chlorophenol-contaminated soil to assess the impact of bioaugmentation with a biodegrading strain on the indigenous microbiota. simultaneously, the impact of 4-chlorophenol alone, or inoculation with a. chlorophenolicus into non-contaminated soil, was addressed. using terminal restriction fragment length polymorphism (t-rflp) several significan ...200219709298
tylenchulus semipenetrans alters the microbial community in the citrus rhizosphere.infection of citrus seedlings by tylenchulus semipenetrans was shown to reduce subsequent infection of roots by phytophthora nicotianae and to increase plant growth compared to plants infected by only the fungus. hypothetical mechanisms by which the nematode suppresses fungal development include nutrient competition, direct antibiosis, or alteration of the microbial community in the rhizosphere to favor microorganisms antagonistic to p. nicotianae. a test of the last hypothesis was conducted via ...200319265991
interactions between strains of 2,4-diacetylphloroglucinol-producing pseudomonas fluorescens in the rhizosphere of wheat.abstract strains of fluorescent pseudomonas spp. that produce the antibiotic 2,4-diacetylphoroglucinol (2,4-dapg) are among the most effective rhizobacteria controlling diseases caused by soilborne pathogens. the genotypic diversity that exists among 2,4-dapg producers can be exploited to improve rhizosphere competence and biocontrol activity. knowing that d-genotype 2,4-dapg-producing strains are enriched in some take-all decline soils and that p. fluorescens q8r1-96, a representative d-genotyp ...200318943865
[cloning and expression of l-n-carbamoylase gene from arthrobacter bt801 in escherichia coli].hydantoin-utility-enzyme is widely used in enzymic production of various amino acids. one of its component, carbamoylase, is responsible for the conversion of n-carbamylamino acids to corresponding amino acids, which is crucial for the stereoselectivity and rate limiting. to improve the production of the enzyme, an l-n-carbamoylase gene from arthrobacter bt801, a hydantoinase producting strain being able to convert 5-benzylhydantoin to phenylalanine, was cloned into e. coli. the gene was highly ...200315966317
[construction of gene library of arthrobacter bt801 and isolation & expression of hydantoinase gene].hydantoinase can be widely used in enzymic production of various amino acids. in order to obtain the hydantoinase genes in arthrobacter bt801, its chromatosomal dna is isolated and partialy digested with sau3a i to collect fragments of about 30kb. then, this fragment is inserted into the hpa i and pst i site of cosmid pkc505. the genomic library was thus constructed by packing in vitro with lambda phage package protein and transfecting e. coli dh5alpha. a positive transformant was selected from ...200315969007
oligosaccharides and derivatives--integrating biocatalyst selectivity and chemical diversity.several biocatalytic pathways are available to synthesize rare sugars, oligosaccharides and derivatives. as examples selective hydrolysis, transglycosylation and regioselective oxidation are presented illustrating their potential. from inulin, difructose anhydrides and inulobiose are accessible via specific hydrolases with transglycosylation activity. glycosyltransferases of the sucrase type utilise sucrose as a versatile substrate for the selective transfer of either glucosyl- or fructosyl unit ...200315296178
[the product identification study on the isolating process of strains produced trehalose].in the isolating process of stains whose endocellular enzymes can produce trehalose on starch or maltooligosaccharides, we discovered the components of enzymatic reactant were complicated and it was difficult to purify them each other, however, we have to know quickly whether there was tehalose in the enzymatic reactant above. in order to make it clearly, thinner layer chromatography, high performance liquid chromatography-electrospray ionization mass spectrometry and 13c-nuclear magnetic resona ...200316276879
molecular cloning of the gene encoding the di-d-fructofuranose 1,2':2,3' dianhydride hydrolysis enzyme (dfa iiiase) from arthrobacter sp. h65-7.the gene encoding an intracellular enzyme hydrolyzing di-d-fructofuranose 1,2':2,3' dianhydride (dfa iii) (dfa iiiase) was cloned from the genomic dna of arthrobacter sp. h65-7 for the first time. the single open reading frame (orf) of the dfa iiiase gene consisted of 1368-bp encoding 455 amino acids. dfa iiiase showed a phylogenetically distinct position from other inulin-degrading enzymes and showed similarity only with inulin fructotransferases (depolymerizing) (inulase ii, ec 2.4.1.93) from ...200316233453
channelling and formation of 'active' formaldehyde in dimethylglycine oxidase.here we report crystal structures of dimethylglycine oxidase (dmgo) from the bacterium arthrobacter globiformis, a bifunctional enzyme that catalyzes the oxidation of n,n-dimethyl glycine and the formation of 5,10-methylene tetrahydrofolate. the n-terminal region binds fad covalently and oxidizes dimethylglycine to a labile iminium intermediate. the c-terminal region binds tetrahydrofolate, comprises three domains arranged in a ring-like structure and is related to the t-protein of the glycine c ...200312912903
[the effect of sulfur on the hydrocarbon-oxidizing bacteria of different genera growth]. 200312751253
mode of action and antifungal properties of two cold-adapted chitinases.the mode of action of two chitinases from the antarctic arthrobacter sp. strain tad20 on n-acetyl-chitooligomers and chitin polymers has been elucidated. identification of the length of chitin oligomers following enzymatic hydrolysis was verified by using hplc-based analysis. it was observed that the length of the oligomer is important for enzyme action. the enzymes cannot effectively hydrolyze chitin oligomers with a degree of polymerization lower than four. archia is an endochitinase which hyd ...200312884086
the structure of 4-hydroxybenzoyl-coa thioesterase from arthrobacter sp. strain su.the 4-chlorobenzoyl-coa dehalogenation pathway in certain arthrobacter and pseudomonas bacterial species contains three enzymes: a ligase, a dehalogenase, and a thioesterase. here we describe the high resolution x-ray crystallographic structure of the 4-hydroxybenzoyl-coa thioesterase from arthrobacter sp. strain su. the tetrameric enzyme is a dimer of dimers with each subunit adopting the so-called "hot dog fold" composed of six strands of anti-parallel beta-sheet flanked on one side by a rathe ...200312907670
gene cluster of arthrobacter ilicis ru61a involved in the degradation of quinaldine to anthranilate: characterization and functional expression of the quinaldine 4-oxidase qoxlms genes.a genetic analysis of the anthranilate pathway of quinaldine degradation was performed. a 23-kb region of dna from arthrobacter ilicis rü61a was cloned into the cosmid pvk100. although escherichia coli clones containing the recombinant cosmid did not transform quinaldine, cosmids harboring the 23-kb region, or a 10.8-kb stretch of this region, conferred to pseudomonas putida kt2440 the ability to cometabolically convert quinaldine to anthranilate. the 10.8-kb fragment thus contains the genes cod ...200312730200
characterization of the 4-hydroxybenzoyl-coenzyme a thioesterase from arthrobacter sp. strain su.the arthrobacter sp. strain su 4-chlorobenzoate (4-cba) dehalogenation pathway converts 4-cba to 4-hydroxybenzoate (4-hba). the pathway operon contains the genes fcba, fcbb, and fcbc (a. schmitz, k. h. gartemann, j. fiedler, e. grund, and r. eichenlaub, appl. environ. microbiol. 58:4068-4071, 1992). genes fcba and fcbb encode 4-cba-coenzyme a (coa) ligase and 4-cba-coa dehalogenase, respectively, whereas the function of fcbc is not known. we subcloned fcbc and expressed it in escherichia coli, a ...200312732540
catabolism of arylboronic acids by arthrobacter nicotinovorans strain pba.arthrobacter sp. strain pba metabolized phenylboronic acid to phenol. the oxygen atom in phenol was shown to be derived from the atmosphere using (18)o(2). 1-naphthalene-, 2-naphthalene-, 3-cyanophenyl-, 2,5-fluorophenyl-, and 3-thiophene-boronic acids were also transformed to monooxygenated products. the oxygen atom in the product was bonded to the ring carbon atom originally bearing the boronic acid substituent with all the substrates tested.200312839810
[xylose(glucose) isomerase reactivity of immobilized arthrobacter sp].the study of the xylose/glucose isomerase-containing arthrobacter sp. b-5 cells immobilized in cobalt hydroxide gel showed that immobilization increases the substrate affinity of the enzyme, its thermo- and ph-optima of action and stability, and makes unnecessary the addition of stabilizing cobalt ions to the isomerization medium.200312901016
ph and deuterium kinetic isotope effects studies on the oxidation of choline to betaine-aldehyde catalyzed by choline oxidase.the fad-dependent choline oxidase catalyzes the four-electron oxidation of choline to glycine-betaine, with betaine-aldehyde as intermediate. the enzyme is capable of accepting either choline or betaine-aldehyde as a substrate, allowing the investigation of the reaction mechanism for both the conversion of choline to betaine-aldehyde and of betaine-aldehyde to glycine-betaine. in the present study, ph and deuterium kinetic isotope effects with [1,2-2h(4)]-choline were used to study the mechanism ...200312922164
cold adaptation of a psychrophilic chitinase: a mutagenesis study.the gene encoding chitinase archib from the antarctic arthrobacter sp. tad20 has been expressed in escherichia coli and the recombinant enzyme purified to homogeneity. in an effort to engineer cold-adapted biocatalysts through rational redesign to operate at elevated temperatures, we performed several mutations aiming to increase the rigidity of the molecular edifice of the selected psychrophilic chitinase. the mutations were designed on the basis of a homology-based three-dimensional model of t ...200312915727
Displaying items 1501 - 1600 of 2332