Publications

TitleAbstractYear
Filter
PMID(sorted descending)
Filter
phylogeny of sphingomonas species that degrade pentachlorophenol.four pentachlorophenol (pcp)-degrading bacteria isolated from geographically diverse areas have been examined in detail as regards their physiology and phylogeny. according to traditional biochemical methods, these strains had been classified as members of the genera arthrobacter, flavobacterium, pseudomonas, and sphingomonas. the pcp degradation pathway has been studied extensively in sphingomonas (flavobacterium) sp strain atcc 39723 and the first three degradation steps catalyzed by a pcp-4-m ...199911423949
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
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
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
separation of listeria from cheese and enrichment media using antibody-coated microbeads and centrifugation.an immunoseparation system for the separation of listeria from enriched cheese samples was developed. the system utilizes polystyrene microbeads (3.8 microm in diameter) coated with covalently bound anti-listeria genus-specific antibody. the beads were incubated with cheese enriched in half-fraser broth and the bead-bacterial complex was separated by centrifugation at 110 g then spread on selective agar plates. although cross-reactivity with certain gram-positive bacteria (staphylococcus saproph ...200111412914
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
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
reaction kinetics and modeling of the enzyme-catalyzed production of lactosucrose using beta-fructofuranosidase from arthrobacter sp. k-1.lactosucrose synthesis from sucrose and lactose was carried out by using beta-fructofuranosidase from arthrobacter sp. k-1. the transfructosylation mechanism was found to be of an ordered bi-bi type in which sucrose was bound first to the enzyme and lactosucrose was released last. hydrolysis side-reaction experiments indicated that the reactions were uncompetitively inhibited by glucose and lactose, while no inhibition by fructose was apparent. the overall reaction rates were formulated. the rea ...200111388450
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
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
plasmid-encoded phthalate catabolic pathway in arthrobacter keyseri 12b.several 2-substituted benzoates (including 2-trifluoromethyl-, 2-chloro-, 2-bromo-, 2-iodo-, 2-nitro-, 2-methoxy-, and 2-acetyl-benzoates) were converted by phthalate-grown arthrobacter keyseri (formerly micrococcus sp.) 12b to the corresponding 2-substituted 3,4-dihydroxybenzoates (protocatechuates). because these products lack a carboxyl group at the 2 position, they were not substrates for the next enzyme of the phthalate catabolic pathway, 3,4-dihydroxyphthalate 2-decarboxylase, and accumula ...200111371533
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
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
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
development of a rhodococcus recombinant strain for degradation of products from anaerobic dechlorination of pcbs.the gram-positive bacterium rhodococcus sp. strain rha1, naturally containing the biphenyl pathway, was electroporated with a broad host range plasmid containing the 4-chlorobenzoate (4-cba) degradation operon (fcb) isolated from arthrobacter globiformis strain kzt1. the recombinant strain grew in medium containing 4-cba and 4-chlorobiphenyl (4-cb) as the only source of carbon, with stoichiometric release of chloride and a molar growth yield on 4-cb that suggested utilization of both biphenyl ri ...200111349275
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
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
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
[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
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
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
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
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
how big is a bacterium? approximation to a correct total cell density of arthrobacter sp. 200111317979
[comparative study of xylose(glucose) isomerase synthesis in arthrobacter strains].the substrate specificity of isomerases produced by six strains of arthrobacter sp. was studied. the role of utilizable carbon sources in controlling enzyme biosynthesis was established. all of the strains studied were found to produce xylose isomerases efficiently, converting d-xylose into d-xylulose and d-glucose into d-fructose. all but a. ureafaciens b-6 strains showed low activity toward d-ribose, arthrobacter sp. b-5 was slightly active toward l-arabinose, and a. ureafaciens b-6 and arthro ...200011314651
16s rdna diversity of cultured and uncultured prokaryotes of a mat sample from lake fryxell, mcmurdo dry valleys, antarctica.the prokaryotic diversity of aerobic and anaerobic bacterial isolates and of bacterial and archaeal 16s rdna clones was determined for a microbial mat sample from the moated region of lake fryxell, mcmurdo dry valleys, antarctica. among the anaerobic bacteria, members of clostridium estertheticum and some other psychrotolerant strains dominated whereas methanogens and other archaea were lacking. isolates highly related to flavobacterium hibernum, janthiniobacterium lividum, and arthrobacter flav ...200111302499
vitamin requirements of hydrocarbon-utilizing soil bacteria.the numbers of oil-utilizing bacteria in several samples of clean and oil-polluted soils counted on vitamin-containing media were severalfold higher than the numbers counted on vitamin-free media. colonies that grew on a medium containing a vitamin mixture were tested for growth on the same medium lacking any vitamins. more than 90% of the total colonies failed to grow. the remaining 10% grew, yet their growth was enhanced, when vitamins were added. the predominant oil-utilizing bacteria in one ...200111297361
biotreatment of hydrogen sulfide- and ammonia-containing waste gases by fluidized bed bioreactor.gas mixtures of h2s and nh3 are the focus of this study of research concerning gases generated from animal husbandry and treatments of anaerobic wastewater lagoons. a heterotrophic microflora (a mixture of pseudomonas putida for h2s and arthrobacter oxydans for nh3) was immobilized with ca-alginate and packed into a fluidized bed reactor to simultaneously decompose h2s and nh3. this bioreactor was continuously supplied with h2s and nh3 separately or together at various ratios. the removal effici ...200111256495
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
purification and characterisation of an ester hydrolase from a strain of arthrobacter species: its application in asymmetrisation of 2-benzyl-1,3-propanediol acylates.an ester hydrolase (abl) has been isolated from a strain of arthrobacter species (rrlj-1/95) maintained in the culture collection of this laboratory. the purified enzyme has a specific activity of 1700 u/mg protein and is found to be composed of a single subunit (mr 32,000), exhibiting both lipase and esterase activities shown by hydrolysis of triglycerides and p-nitrophenyl acetate respectively. potential application of the enzyme concerns the asymmetrisation of prochiral 2-benzyl-1,3-propanedi ...200111249119
analysis of bacterial community structure in sulfurous-oil-containing soils and detection of species carrying dibenzothiophene desulfurization (dsz) genes.the selective effects of sulfur-containing hydrocarbons, with respect to changes in bacterial community structure and selection of desulfurizing organisms and genes, were studied in soil. samples taken from a polluted field soil (a) along a concentration gradient of sulfurous oil and from soil microcosms treated with dibenzothiophene (dbt)-containing petroleum (fsl soil) were analyzed. analyses included plate counts of total bacteria and of dbt utilizers, molecular community profiling via soil d ...200111229891
use of green fluorescent protein and luciferase biomarkers to monitor survival and activity of arthrobacter chlorophenolicus a6 cells during degradation of 4-chlorophenol in soil.the recently isolated novel species arthrobacter chlorophenolicus a6 is capable of growth on and degradation of high concentrations of 4-chlorophenol (up to 350 microg ml(-1)) as the sole carbon and energy source. this strain shows promise for bioremediation of environmental sites contaminated with high levels of chlorophenols. in this study, green fluorescent protein (gfp) or luciferase (luc) genes were used as biomarkers for monitoring cell number and activity, respectively, during degradation ...200111225721
development of an escherichia coli whole cell biocatalyst for the production of l-amino acids.a whole cell biocatalyst for the enzymatic production of l-amino acids from hydantoins was created by coexpressing the genes encoding the l-hydantoinase, the l-n-carbamoylase and the hydantoin racemase from arthrobacter aurescens in escherichia coli. in order to construct a well balanced reaction system the enzymatic activity in the cells was varied by using vectors with different copy numbers for expression of the genes. derivatives of psc101, pacyc184 and pbr322 were employed for the various c ...200111223141
arthrobacter siderocapsulatus dubinina and zhdanov 1975al is a later subjective synonym of pseudomonas putida (trevisan 1889) migula 1895al.the taxonomic position of arthrobacter siderocapsulatus dubinina and zhdanov 1975al was investigated using 16s rdna, fatty acid and phenotypic analyses. the type strain (ncimb 11286t) showed 99.85% 16s rdna similarity to the type strain of pseudomonas putida. phenotypic properties of the two strains were compared using api 20ne and biolog kits. identical reactions were recorded for all tests, except for assimilation of malonic acid. the two strains also showed almost identical cellular fatty aci ...200111211254
cultivatable microbial biodiversity: gnawing at the gordian knot.rapid and inexpensive sorting of bacterial isolates may be achieved using fourier transform infrared spectroscopy (ft-ir), a method that has hitherto been applied to identification and classification. the comprehensive characterization of environmental samples requires the isolation of large numbers of isolates using different growth media and growth conditions. in such cases, sorting the isolates is critical before isolates are subjected to more detailed studies. using ft-ir, isolates are grown ...200011200432
degradation of o-methoxybenzoate by a two-member consortium made up of a gram-positive arthrobacter strain and a gram-negative pantotea strain.aromatic carboxylic acids substituted with methoxylated groups are among the most abundant products in "alpechin", the wastes resulting from pressing olives to obtain olive oil. degradation of o-methoxybenzoate by an stable consortium made of a gram positive bacterium, arthrobacter oxydans, and gram negative one, pantotea agglomerans, was shown to mineralize this compound efficiently. the concerted action of both microorganisms was needed for the two first steps in the process, namely, the conve ...200011194973
[two different fermentation techniques of steriod 1,4-dehydrogenation and 11 alpha-hydroxylation].two kinds of micro-organism, arthrobacter sp. ax86(1,4-dehdrogenator) and absidia sp. a28(11 alpha-hydroxylator) were used in this experiment. two different fermentation techniques were performed to accomplish the multiple conversional reactions for producing 16 beta-methyl-11 alpha,17 alpha,21-trihydroxy-1,4-pregnadiene-3,20-dione(iii) from 16 beta-methyl-3 beta,17 alpha,21-trihydroxy-5 alpha-pregnane-20-one-21-acetate(i): 1) to produce product(iii) by means of a two-step fermentation method wh ...200011191778
purification and characterization of aminopropionaldehyde dehydrogenase from arthrobacter sp. tmp-1.aminopropionaldehyde dehydrogenase was purified to apparent homogeneity from 1,3-diaminopropane-grown cells of arthrobacter sp. tmp-1. the native molecular mass and the subunit molecular mass of the enzyme were approximately 20,5000 and 52,000, respectively, suggesting that the enzyme is a tetramer of identical subunits. the apparent michaelis constant (k(m)) for 1,3-diaminopropane was approximately 3 microm. the enzyme equally used both nad(+) and nadp(+) as coenzymes. the apparent k(m) values ...200111179651
secretory production of arthrobacter levan fructotransferase from recombinant escherichia coli.levan fructotransferase (lftase) from arthrobacter ureafaciens k2032 was expressed with n-terminal fusion of a lacz-derived secretion motif (tmitnsssvp) using the lac promoter system in recombinant escherichia coli jm109 [pudf-a81]. in flask cultures, recombinant enzyme activity was detected in culture media, and sequence analysis of n-terminal residues showed that about 40% of the extracellular recombinant lftase had an authentic n-terminus. in a fed-batch bioreactor containing recombinant e. c ...200111179640
study of the structure-activity relationships for the pyrazinamidase (pnca) from mycobacterium tuberculosis.in an attempt to investigate the molecular basis of pyrazinamide hydrolysis by the pnca protein from mycobacterium tuberculosis, we determined the pyrazinamidase activity of nine pnca mutants bearing a single amino acid substitution. among them, three mutants (d8g, k96t and s104r) had virtually no activity (< or =0.004 unit/mg), five (f13s, t61p, p69l, y103s and a146v) retained a low level of activity (0.06-0.25 unit/mg) and one (t167l) exhibited a wild-type activity (1.51 units/mg). the possibl ...200111171040
a unique sialidase that cleaves the neu5gcalpha2-->5-o(glycolyl)neu5gc linkage: comparison of its specificity with that of three microbial sialidases toward four sialic acid dimers.we found that the hepatopancreas of oyster, crassostrea virginica, contained a sialidase capable of releasing neu5gc from the novel polysialic acid chain (-->5-o(glycolyl)neu5gcalpha2-->)n more efficiently than from the conventional type of polysialic acid chains, (-->8neu5acalpha2-->)n, or (-->8neu5gcalpha2-->)n. we have partially purified this novel sialidase and compared its reactivity with that of microbial sialidases using four different sialic acid dimers, neu5gcalpha2-->5-o(glycolyl)neu5g ...200111162485
cloning, sequences, and characterization of two chitinase genes from the antarctic arthrobacter sp. strain tad20: isolation and partial characterization of the enzymes.arthrobacter sp. strain tad20, a chitinolytic gram-positive organism, was isolated from the sea bottom along the antarctic ice shell. arthrobacter sp. strain tad20 secretes two major chitinases, chia and chib (archia and archib), in response to chitin induction. a single chromosomal dna fragment containing the genes coding for both chitinases was cloned in escherichia coli. dna sequencing analysis of this fragment revealed two contiguous open reading frames coding for the precursors of archia (8 ...200111160110
arthrobacter chlorophenolicus sp. nov., a new species capable of degrading high concentrations of 4-chlorophenol.a micro-organism was isolated from soil which could grow on high concentrations [up to 350 p.p.m. (2.7 mm)] of 4-chlorophenol (4-cp). the isolate, designated strain a6t, was obtained from a soil suspension that had been selectively enriched with gradually increasing concentrations of 4-cp. strain a6t could also grow on several other para-substituted phenols. characterization of strain a6t with respect to chemical, biochemical and morphological properties, 16s rdna sequencing and dna-dna hybridiz ...200011155983
bioremediation of polychlorinated biphenyl-contaminated soil using carvone and surfactant-grown bacteria.partial bioremediation of polychlorinated biphenyl (pcb)-contaminated soil was achieved by repeated applications of pcb-degrading bacteria and a surfactant applied 34 times over an 18-week period. two bacterial species, arthrobacter sp. strain b1b and ralstonia eutrophus h850, were induced for pcb degradation by carvone and salicylic acid, respectively, and were complementary for the removal of different pcb congeners. a variety of application strategies was examined utilizing a surfactant, sorb ...200011152078
glucose isomerase: insights into protein engineering for increased thermostability.thermostable glucose isomerases are desirable for production of 55% fructose syrups at >90 degrees c. current commercial enzymes operate only at 60 degrees c to produce 45% fructose syrups. protein engineering to construct more stable enzymes has so far been relatively unsuccessful, so this review focuses on elucidation of the thermal inactivation pathway as a future guide. the primary and tertiary structures of 11 class 1 and 20 class 2 enzymes are compared. within each class the structures are ...200011150612
analysis of bacterial communities in the rhizosphere of chrysanthemum via denaturing gradient gel electrophoresis of pcr-amplified 16s rrna as well as dna fragments coding for 16s rrna.the effect of developing chrysanthemum roots on the presence and activity of bacterial populations in the rhizosphere was examined by using culture-independent methods. nucleic acids were extracted from rhizosphere soil samples associated with the bases of roots or root tips of plants harvested at different stages of development. pcr and reverse transcriptase (rt) pcr were used to amplify 16s ribosomal dna (rdna) and 16s rrna, respectively, and the products were subjected to denaturing gradient ...200111133442
trypsin inhibitory activity of bovine fetuin de-o-glycosylated by endo-alpha-n-acetylgalactosaminidase.the effects of bovine fetuin o-glycans on its trypsin inhibitory activity were examined. de-sialylated (asialo-) and de-o-glycosylated fetuin were prepared from native fetuin using arthrobacter neuraminidase and the mixture of it and bacillus endo-alpha-n-acetylgalactosaminidase, respectively. de-sialylation and de-o-glycosylation from fetuin were confirmed with sds-page followed by western blotting using anti-human thomsen-friedenreich antigen (t antigen) antibody which recognizes o-linked gala ...200011129611
change in receptor-binding specificity of recent human influenza a viruses (h3n2): a single amino acid change in hemagglutinin altered its recognition of sialyloligosaccharides.human h3n2 influenza a viruses were known to preferentially bind to sialic acid (sa) in alpha2,6gal linkage on red blood cells (rbc). however, h3n2 viruses isolated in mdck cells after 1992 did not agglutinate chicken rbc (crbc). experiments with point-mutated hemagglutinin (ha) of a/aichi/51/92, one of these viruses, revealed that an amino acid change from glu to asp at position 190 (e190d) was responsible for the loss of ability to bind to crbc. a/aichi/51/92 did not agglutinate crbc treated w ...200011118381
bacterial release of arsenic ions and organoarsenic compounds from soil contaminated by chemical warfare agents.the objective of this paper was to investigate possible participation of microorganisms in the release of soluble arsenical compounds from organoarsenic warfare agents in contaminated soil. a number of bacterial strains were isolated with high resistance against as3+ and as5+ ions which are able to degrade the water insoluble compounds triphenylarsine (tp) and triphenylarsineoxide (tpo). these strains belong to different genera of bacteria. release of arsenic ions and soluble organoarsenic compo ...200111100795
diversity of l-methionine catabolism pathways in cheese-ripening bacteria.enzymatic activities that could be involved in methanethiol generation in five cheese-ripening bacteria were assayed, and the major sulfur compounds produced were identified. l-methionine and alpha-keto-gamma-methyl-thio-butyric acid demethiolating activities were detected in whole cells and cell extracts (cfes) of all the bacteria tested. no l-methionine deaminase activity could be detected in any of the ripening bacteria and l-methionine aminotransferase was detected in cfes of brevibacterium ...200011097940
enhanced tolerance of transgenic brassica juncea to choline confirms successful expression of the bacterial coda gene.brassica juncea cv. pusa jaikisan was transformed with the coda gene for choline oxidase from arthrobacter globiformis with an aim to introduce glycine betaine biosynthetic pathway, as it lacks any means to synthesize glycine betaine. western blot analysis revealed the presence of choline oxidase in the protein extract from the coda transgenic lines, demonstrating that the bacterial coda gene had been successfully transcribed and translated in transgenic lines. good activity of choline oxidase i ...200011074276
monitoring bacterial transport by stable isotope enrichment of cells.understanding the transport and behavior of bacteria in the environment has broad implications in diverse areas, ranging from agriculture to groundwater quality, risk assessment, and bioremediation. the ability to reliably track and enumerate specific bacterial populations in the context of native communities and environments is key to developing this understanding. we report a novel bacterial tracking approach, based on altering the stable carbon isotope value (delta(13)c) of bacterial cells, w ...200011055946
enzymatic assay of histamine by amperometric detection of h2o2 with a peroxidase-based sensor.a method for an enzymatic assay of histamine by using histamine oxidase from arthrobacter globiformis in combination with amperometric determination of h2o2 is described. histamine could be quantified at a level as low as 10(-7) m. the assay is adaptable to determine histamine in food samples including tuna fish with good sensitivity and selectivity.200011055403
measuring growth of a phenanthrene-degrading bacterial inoculum in soil with a quantitative competitive polymerase chain reaction method.we measured growth of a phenanthrene-degrading bacterium, arthrobacter, strain rp17, in forbes soil, amended with 500 µg g(-1) phenanthrene using a quantitative competitive polymerase chain reaction method. the inoculum, which was not indigenous to forbes soil, grew from 5.55x10(5) colony forming units (cfu) g(-1) to 1.97x10(7) cfu g(-1) within 100 h after the cells were added to the soil. maximum population density was reached before the highest degradation rate was observed 150 h after the cel ...200011053730
a mutant sarcosine oxidase in which activity depends on flavin adenine dinucleotide.the covalent flavin attachment site in the arthrobacter sarcosine oxidase (cysteine at position 318) was replaced with serine, and the mutational effect of c318s was analyzed. wild type and c318s with a c-terminal 6-histidine tag were constructed and homogeneously purified by the single step. the covalently binding to flavin was not essential to the enzyme activity because the c318s mutant exhibited extremely weak activity. moreover, the activity of the mutant was recovered in the presence of fl ...200011035956
3-carbamoyl-alpha-picolinic acid production by imidase-catalyzed regioselective hydrolysis of 2,3-pyridinedicarboximide in a water-organic solvent, two-phase system.3-carbamoyl-alpha-picolinic acid, a versatile building block for the synthesis of agrochemicals and pharmaceuticals, was prepared by imidase-catalyzed regiospecific hydrolysis of 2,3-pyridinedicarboximide with intact arthrobacter ureafaciens o-86 cells. reactions were carried out in a water-organic solvent, two-phase system containing cyclohexanone at low ph to avoid spontaneous random hydrolysis. under the optimized conditions, with the periodic addition of 2,3-pyridinedicarboximide (in total, ...200011030568
renibacterium salmoninarum isolates from different sources possess two highly conserved copies of the rrna operon .the nucleotide sequences of the rrna genes and the 5' flanking region were determined for r. salmoninarum atcc 33209t from overlapping products generated by pcr amplification from the genomic dna. comparison of the sequences with rrna genes from a variety of bacteria demonstrated the close relatedness between r. salmoninarum and the high g+c group of the actinobacteria, in particular, arthrobacter species. a regulatory element within the 5' leader of the rrna operon was identical to an element, ...200011016696
microbial diversity during maturation and natural processing of coffee cherries of coffea arabica in brazil.the magnitude and diversity of the microbial population associated with dry (natural) processing of coffee (coffea arabica) has been assessed during a 2-year period on 15 different farms in the sul de minas region of brazil. peptone water-washed samples were taken of maturing cherries on trees (cherries, raisins and dried cherries) and from ground fermentations. the microbial load varied from 3 x 10(4) to 2.2 x 10(9) cfu/cherry with a median value of 1.6 x 10(7) cfu/cherry. the microbial load in ...200011016614
microbial species associated with different sections of broccoli harvested from three regions in australia.the microbial populations associated with the different sections of broccoli harvested from three locations in australia were studied during storage at 5, 15 and 20 degrees c. bacterial and yeast populations associated with the outer florets and cut surfaces of the stem were generally 10-fold or more higher than those associated with inner florets or non-cut stems, respectively. the predominating bacterial species varied with the origin of the broccoli. pseudomonas fluorescens, ps. corrugata and ...200011014518
expression of podocalyxin inhibits cell-cell adhesion and modifies junctional properties in madin-darby canine kidney cells.podocalyxin is a major membrane protein of the glomerular epithelium and is thought to be involved in maintenance of the architecture of the foot processes and filtration slits characteristic of this unique epithelium by virtue of its high negative charge. however, until now there has been no direct evidence for podocalyxin's function. podocalyxin is a type 1 transmembrane sialoprotein with an n-terminal mucin-like domain. to assess its function, we cloned rat podocalyxin and examined the effect ...200010982412
microbiology of the stalactites from grotta dei cervi, porto badisco, italy.the active stalactites from grotta dei cervi, porto badisco, southeastern italy, were sampled to investigate the microbial communities present in these speleothems. sampling was carried out in a transect about 150 m long in the central gallery, where numerous gram-positive bacteria were isolated. actinomycetes of the genus streptomyces were the most abundant, followed by members of the genus bacillus. further isolates were assigned to the genera amycolatopsis, arthrobacter; agromyces. micrococcu ...200010963330
changes of cell size distribution during the batch culture of arthrobacter strain pi/1-95.the size distributions of an arthrobacter, approximately 1 microm in diameter, were analysed using a coulter multisizer ii instrument thereby making it possible to distinguish between the different stages in the morphological cycle. the results indicated that at the beginning of exponential phase a shift occurred from large to smaller cells, the cell size distributions in both categories were asymmetric, skewed towards higher values than the means. during the course of the batch culture the cell ...200010959562
gene cloning and overproduction of low-specificity d-threonine aldolase from alcaligenes xylosoxidans and its application for production of a key intermediate for parkinsonism drug.the dtaax gene encoding a pyridoxal 5'-phosphate (pyridoxal-p)-dependent low-specificity d-threonine aldolase was cloned from the chromosomal dna of alcaligenes xylosoxidans ifo 12669. it contains an open reading frame consisting of 1,134 nucleotides corresponding to 377 amino acid residues. the predicted amino acid sequence displayed 54% identity with that of d-threonine aldolase from gram-positive bacteria arthrobacter sp. dk-38, but showed no significant similarity with those of other known p ...200010952004
effect of associative bacteria on element composition of barley seedlings grown in solution culture at toxic cadmium concentrations.the response of barley seedlings to inoculation with associative rhizobacteria azospirillum lipoferum 137, arthrobacter mysorens 7, agrobacterium radiobacter 10 and flavobacterium sp. l30 was studied in hydroponic and quartz sand cultures in the presence of 50 microm cdcl2. cadmium caused severe inhibition in the growth and uptake of nutrient elements by the plants. inoculation with the bacteria slightly stimulated root length and biomass of hydroponically grown cd-treated seedlings. the bacteri ...200010950194
hydantoin racemase from arthrobacter aurescens dsm 3747: heterologous expression, purification and characterization.in arthrobacter aurescens dsm 3747 three enzymes are involved in the complete conversion of slowly racemizing 5'-monosubstituted d,l-hydantoins to l-amino acids, a stereoselective hydantoinase, a stereospecific l-n-carbamoylase and a hydantoin racemase. the gene encoding the hydantoin racemase, designated hyua, was identified upstream of the previously described l-n-carbamoylase gene in the plasmid paw16 containing genomic dna of a. aurescens. the gene hyua which encodes a polypeptide of 25.1 kd ...200010949312
overexpression, purification, and characterization of bacillus subtilis n-acetylmuramoyl-l-alanine amidase cwlc.n-acetylmuramoyl-l-alanine amidase cwlc of bacillus subtilis was overproduced in escherichia coli and purified 21-fold. the amidase hydrolyzed type a cell walls such as b. subtilis. the amidase bound slightly to the microbacterium lacticum cell wall (type b), but did not entirely hydrolyze it. the presence of calcium or magnesium ion increased the resistance of the amidase to heat denaturation.200010945275
difructose anhydrides: their mass-production and physiological functions.difructose anhydrides (dfas) are the smallest cyclic disaccharides consisting of two fructose residues, and are expected to have novel physiological functions from their unique structures and properties. for mass-production of alpha-d-fructofuranose-beta-d-fructofuranose-2',1:2,3'-dianhydride (dfa iii) and beta-d-fructofuranose-beta-d-fructofuranose-2',6:2,6'-dianhydride (dfa iv), arthrobacter sp. h65-7 and a. nicotinovorans gs-9 were selected as the best producers of inulase ii, which produced ...200010945246
arthrobacter flavus sp. nov., a psychrophilic bacterium isolated from a pond in mcmurdo dry valley, antarctica.cms 19yt, a psychrophilic bacterium, was isolated from a cyanobacterial mat sample from a pond in antarctica and was characterized taxonomically. the bacterium was aerobic, gram-positive, non-spore-forming, non-motile, exhibited a rod-coccus growth cycle and produced a yellow pigment that was insoluble in water but soluble in methanol. no growth factors were required and it was able to grow between 5 and 30 degrees c, between ph 6 and ph 9 and tolerated up to 11.5% nacl. the cell wall peptidogly ...200010939663
genetic engineering of glycinebetaine synthesis in plants: current status and implications for enhancement of stress tolerance.metabolic acclimation via the accumulation of compatible solutes is regarded as a basic strategy for the protection and survival of plants in extreme environments. certain plants accumulate significant amounts of glycinebetaine (betaine), a compatible quaternary amine, in response to high salinity, cold and drought. it is likely that betaine is involved in the protection of macrocomponents of plant cells, such as protein complexes and membranes, under stress conditions. genetic engineering of th ...200010938798
kinetics of biodegradation of p-nitrophenol by different bacteria.three bacterial species, i.e., ralstonia sp. sj98, arthrobacter protophormiae rkj100, and burkholderia cepacia rkj200, have been examined for their efficiency and kinetics behavior toward pnp degradation. all the three bacteria utilized pnp as the sole source of carbon, nitrogen, and energy. the rates of radiolabeled [u-(14)c]pnp degradation by all the bacteria were higher in the nitrogen-free medium compared to the medium with nitrogen. the apparent k(m) values of pnp degradation by sj98, rkj10 ...200010924328
[formation of resting forms of arthrobacter globiformis in autolysing cell suspensions].under conditions of spontaneous or induced autolysis of thick cell suspensions, arthrobacter globiformis strains produced cells exhibiting features typical of resting microbial forms. the number of viable resting cells was greater under conditions of induced rather than spontaneous autolysis. the thermoresistance of the resting cells of a. globiformis strains isolated from 2- to 3 million-year-old permafrost was higher than that of the collection a. globiformis strain.200010920809
[reproductive resting forms of arthrobacter globiformis].submerged cultures of arthrobacter globiformis grown in media unbalanced with respect to carbon and nitrogen sources were found to contain cells exhibiting features typical of resting forms: long-term viability, specific ultrastructure, dormant metabolism, and thermoresistance. such cells were produced not only in the collection strain vkm b-1112, but also in the a. globiformis strains isolated from 2- to 3-million-year-old permafrost sediments.200010920808
effect of field inoculation with sinorhizobium meliloti l33 on the composition of bacterial communities in rhizospheres of a target plant (medicago sativa) and a non-target plant (chenopodium album)-linking of 16s rrna gene-based single-strand conformation polymorphism community profiles to the diversity of cultivated bacteria.fourteen weeks after field release of luciferase gene-tagged sinorhizobium meliloti l33 in field plots seeded with medicago sativa, we found that the inoculant also occurred in bulk soil from noninoculated control plots. in rhizospheres of m. sativa plants, s. meliloti l33 could be detected in noninoculated plots 12 weeks after inoculation, indicating that growth in the rhizosphere preceded spread into bulk soil. to determine whether inoculation affected bacterial diversity, 1,119 bacteria were ...200010919821
genetic diversity among arthrobacter species collected across a heterogeneous series of terrestrial deep-subsurface sediments as determined on the basis of 16s rrna and reca gene sequences.this study was undertaken in an effort to understand how the population structure of bacteria within terrestrial deep-subsurface environments correlates with the physical and chemical structure of their environment. phylogenetic analysis was performed on strains of arthrobacter that were collected from various depths, which included a number of different sedimentary units from the yakima barricade borehole at the u.s. department of energy's hanford site, washington, in august 1992. at the same t ...200010919806
comparison of colony lift with direct spotting methods of blot preparation on the effect of colony hybridization in the detection of environmental organisms.nucleic acid probes are used on site to detect or to identify individual microbial cells without cultivation. this molecular technique can avoid some limitations of traditional identification methods including time consuming and imprecise. this study examined the factors affecting colony hybridization and compared the effectiveness of membrane prepared by colony lifting with direct spotting procedures using the universal probe eub 338. the results of hybridization varied depending on the type of ...200010917884
specific detection of p-chlorobenzoic acid by escherichia coli bearing a plasmid-borne fcba'::lux fusion.in this communication we report on a genetically engineered bacterium that reacts by light emission to the presence of 4-chlorobenzoic acid. to construct this strain, dna fragment (1.7 kb) upstream from the 4-chlorobenzoic acid dehalogenase (fcb) operon of arthrobacter su was fused to vibriofischeri luxcdabe genes. an escherichia coli strain transformed with a multi-copy plasmid (pasu) bearing this fusion responded to the presence of 4-chlorobenzoic acid and a few closely related compounds by in ...199910901680
characteristics of levan fructotransferase from arthrobacter ureafaciens k2032 and difructose anhydride iv formation from levan.a microorganism producing levan fructotransferase was isolated from sugar-disclosed soil and it was identified as arthrobacter ureafaciens. the major product from levan by enzyme reaction was identified as di-d-fructofuranose 2,6':6,2' dianhydride by mass spectrometry, nuclear magnetic resonance, and chemical analyses. small amounts of several oligosaccharides and free fructose were also formed by enzyme reaction. an extracellular enzyme that produces di-d-fructofuranose 2,6':6,2' dianhydride fr ...200010899545
dimethylsulfone as a growth substrate for novel methylotrophic species of hyphomicrobium and arthrobacter.dimethylsulfone is a major product of the chemical oxidation in the atmosphere of the principal biogenic sulfur gas, dimethylsulfide, but no studies have been reported on the mechanisms for its microbiological degradation. three novel strains of bacteria have been isolated from enrichment cultures provided with dimethylsulfone as the only carbon and energy substrate. these are novel facultatively methylotrophic species of hyphonmicrobium and arthobacter, capable of growth on a range of one-carbo ...200010896224
determination of n-acetyl- and n-glycolylneuraminic acids in gangliosides by combination of neuraminidase hydrolysis and fluorometric high-performance liquid chromatography using a gm3 derivative as an internal standard.a highly sensitive method for quantification of sialic acids in gangliosides was developed. the sialic acids, released by hydrolysis of gangliosides, were converted to fluorescent derivatives with 1,2-diamino-4,5-(methylenedioxy)benzene (dmb) and separated on a reversed-phase c18 column with an isocratic elution. as little as 0.1-1.0 nmol of sialic acid in ganglioside was quantified. the use of acetate buffer instead of water in the mobile phase could prevent damage on the column and reduce back ...200010870835
transformation of arabidopsis with the coda gene for choline oxidase enhances freezing tolerance of plants.arabidopsis thaliana was transformed with the coda gene from arthrobacter globiformis, which encodes choline oxidase, the enzyme that synthesizes glycinebetaine from choline. the transformation enabled the plants to accumulate glycinebetaine in chloroplasts, and significantly enhanced the freezing tolerance of plants. furthermore, the photosynthetic machinery of transformed plants was more tolerant to freezing stress than that of wild-type plants. exogenous application of glycinebetaine also inc ...200010849360
phylogenetic and physiological diversity of arthrobacter strains isolated from unconsolidated subsurface sediments.forty strains of gram-positive, aerobic, heterotrophic bacteria isolated from saturated subsurface lacustrine, paleosol and fluvial sediments at the us department of energy's hanford site in south central washington state were characterized by phylogenetic analysis of 16s rrna gene sequences and by determination of selected morphological, physiological and biochemical traits. phylogenetic analyses of 16s rdna sequences from subsurface isolates in the context of similar sequences from previously ...200010846209
purification and characterization of a novel dna repair enzyme from the extremely radioresistant bacterium rubrobacter radiotolerans.rubrobacter radiotolerans is an extremely radioresistant bacterium. it exhibits higher resistance than the well-known radioresistant bacterium deinococcus radiodurans, but the molecular mechanisms responsible for the radio-resistance of r. radiotolerans remain unknown. in the present study, we have demonstrated the presence of a novel dna repair enzyme in r. radiotolerans cells that recognizes radiation-induced dna damages such as thymine glycol, urea residues, and abasic sites. the enzyme was p ...200010838807
identification of arthrobacter oxydans, arthrobacter luteolus sp. nov., and arthrobacter albus sp. nov., isolated from human clinical specimens.five arthrobacter isolates from clinical specimens were studied by phenotypic, chemotaxonomic, and genetic characterization. two strains had characteristics consistent with those of arthrobacter oxydans. one strain was related to a. citreus; however, dna-dna hybridization and phenotypic characteristics indicated that this strain belongs to a new species, for which the name arthrobacter luteolus sp. nov. is proposed. two strains were closely related to a. cumminsii by 16s rrna gene sequencing, bu ...200010835019
structural analysis of the elongation factor g protein from the low-temperature-adapted bacterium arthrobacter globiformis si55.the first structural analysis of elongation factor g (ef-g) from a cold-adapted bacterium is presented. ef-g is an essential protein involved in the elongation process during protein synthesis and is therefore thought to play a crucial role in the low-temperature adaptation of cold-adapted microorganisms. to define its importance, the ef-g gene (fus) from the psychrotolerant bacterium arthrobacter globiformis si55 was cloned and sequenced. the deduced primary structure of the elongation factor i ...200010805567
plasmid-encoded degradation of p-nitrophenol and 4-nitrocatechol by arthrobacter protophormiae.arthrobacter protophormiae strain rkj100 is capable of utilizing p-nitrophenol (pnp) as well as 4-nitrocatechol (nc) as the sole source of carbon, nitrogen and energy. the degradation of pnp and nc by this microorganism takes place through an oxidative route, as stoichiometry of nitrite molecules was observed when the strain was grown on pnp or nc as sole carbon and energy sources. the degradative pathways of pnp and nc were elucidated on the basis of enzyme assays and chemical characterization ...200010772893
microbial responses to environmentally toxic cadmium.we analyzed the soil microbial communities from one uncontaminated and two metal-impacted soils and found that while cadmium adversely affected the numbers of culturable bacteria in all soils, cadmium-resistant isolates were found from each of the soils. with exposure to 24 and 48 µg ml(-1) soluble cadmium, the metal-contaminated soil communities were more resistant than the uncontaminated soil community. in addition, in one metal-stressed soil, the resistant population became more resistant wit ...199910758182
identification of coryneform bacterial isolates by ribosomal dna sequence analysis.identification of coryneform bacteria to the species level is important in certain circumstances for differentiating contamination and/or colonization from infection, which influences decisions regarding clinical intervention. however, methods currently used in clinical microbiology laboratories for the species identification of coryneform bacteria are often inadequate. we evaluated the microseq 500 16s bacterial sequencing kit (perkin-elmer biosystems, foster city, calif.), which is designed to ...200010747168
molecular cloning, sequencing, expression, and site-directed mutagenesis of the 1h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase gene from arthrobacter spec. rü61a.the ring cleaving enzyme 1h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase (hod)) of arthrobacter spec. rü61a is part of the quinaldine degradation pathway. carbon monoxide and n-acetyl-anthranilate are the products formed by dioxygenolytic cleavage of two c-c bonds in the substrate's pyridine ring. the gene coding for hod was cloned and sequenced. an isoelectric point of ph 5.40 and a molecular mass of 31,838 da was deduced from the sequence. hod is shown to be remarkably similar to 1h-3-hydroxy-4-o ...200010746195
inverting enantioselectivity by directed evolution of hydantoinase for improved production of l-methionine.using directed evolution, we have improved the hydantoinase process for production of l-methionine (l-met) in escherichia coli. this was accomplished by inverting the enantioselectivity and increasing the total activity of a key enzyme in a whole-cell catalyst. the selectivity of all known hydantoinases for d-5-(2-methylthioethyl)hydantoin (d-mteh) over the l-enantiomer leads to the accumulation of intermediates and reduced productivity for the l-amino acid. we used random mutagenesis, saturatio ...200010700149
[conjugative transfer of a plasmid from escherichia coli to various strains of the order actinomycetales].the conjugal transfer of autonomous and integrative plasmids from the donor strain escherichia coli s17-1 to strains of genera actinomadura, arthrobacter, kitasatoa, micromonospora, nocardia, rhodococcus, saccharopolyspora, and to 16 strains of the genus streptomyces was demonstrated. the status of plasmids in recipient strains and the stability of their inheritance were analyzed. plasmids constructed for strains of the genus streptomyces were shown to function in a large number of strains belon ...199910687092
kinetic studies of the mechanism of carbon-hydrogen bond breakage by the heterotetrameric sarcosine oxidase of arthrobacter sp. 1-in.the reaction of heterotetrameric sarcosine oxidase (tsox) of arthrobactor sp. 1-in has been studied by stopped-flow spectroscopy, with particular emphasis on the reduction of the enzyme by sarcosine. expression of the cloned gene encoding tsox in escherichia coli enables the production of tsox on a scale suitable for stopped-flow studies. treatment of the enzyme with sulfite provides the means for selective formation of a flavin-sulfite adduct with the covalent 8alpha-(n(3)-histidyl)-fmn. format ...200010684595
purification of recombinant hydantoinase and l-n-carbamoylase from arthrobacter aurescens expressed in escherichia coli: comparison of wild-type and genetically modified proteins.two enzymes, hydantoinase (hyuh) and l-n-carbamoylase (hyuc), are required for the biocatalytic production of natural and unnatural, optically pure l-amino acids starting from d,l-5-monosubstituted hydantoins using the so called 'hydantoinase-method'. for the preparation of immobilized enzymes, which omit several drawbacks of whole cell biocatalysts, purified or at least enriched hyuh and hyuc have to be provided. in order to simplify existing purification protocols several genetically modified ...200010681054
cloning and nucleotide sequence of a gene encoding a glycogen debranching enzyme in the trehalose operon from arthrobacter sp. q36.a gene located just upstream of the treyz operon was isolated from arthrobacter sp. strain q36. the gene, designated trex, encoded an 823-amino acid protein. the amino acid sequence of the protein had 50% identity with the trex protein (isoamylase) from sulfolobus acidocaldarius atcc 33909 which has a trezxy operon on the genome. we suggest that arthrobacter trex is an isoamylase gene, and that it is a component of a trexyz operon.200010669803
cloning and sequence analysis of the gene for glucodextranase from arthrobacter globiformis t-3044 and expression in escherichia coli cells.the gld gene for glucodextranase from arthrobacter globiformis t-3044 was cloned by using a combination of gene walking and probe methods and expressed on the recombinant plasmid pgd8, which was constructed with puc118, in escherichia coli cells. the enzyme gene consisted of a unique open reading frame of 3,153 bp. the comparison of the dna sequence data with the n-terminal and 6 internal amino acid sequences of the purified enzyme secreted from a. globiformis t-3044 suggested the enzyme was tra ...199910664850
degradation of phenanthrene by different bacteria: evidence for novel transformation sequences involving the formation of 1-naphthol.four polycyclic aromatic hydrocarbon (pah)-degrading bacteria, namely arthrobacter sulphureus rkj4, acidovorax delafieldii p4-1, brevibacterium sp. hl4 and pseudomonas sp. dlc-p11, capable of utilizing phenanthrene as the sole source of carbon and energy, were tested for its degradation using radiolabelled phenanthrene. [9-14c]phenanthrene was incubated with microorganisms containing 100 mg/l unlabelled phenanthrene and the evolution of 14co2 was monitored: within 18 h of incubation, 30.1, 35.6, ...199910645629
humus bacteria of norway spruce stands: plant growth promoting properties and birch, red fescue and alder colonizing capacity.we studied the potential of the humus layer of the norway spruce stands to supply beneficial rhizobacteria to birch (betula pendula), alder (alnus incana) and fescue grass (festuca rubra), representatives of pioneer vegetation after clear-cutting of the coniferous forest. axenically grown seedlings of these species were inoculated with the acid spruce humus, ph 3.7-5.3. actinorhizal propagules, capable of nodulating alder, were present in high density (10(3) g(-1)) in humus of long-term limed pl ...200010640667
degradation of o-nitrobenzoate via anthranilic acid (o-aminobenzoate) by arthrobacter protophormiae: a plasmid-encoded new pathway.an arthrobacter protophormiae strain rkj100, isolated by selective enrichment, was capable of utilizing o-nitrobenzoate (onb(+)) as the sole carbon, nitrogen, and energy source. the degradation of onb proceeds through an oxygen insensitive reductive route as shown by the release of ammonia in the culture medium aerobically rather than nitrite ions. thin-layer chromatography, gas chromatography, and gas chromatography-mass spectrometry of the intermediates have shown that onb is degraded by a two ...200010623604
synthesis of neoglycoenzymes with homogeneous n-linked oligosaccharides using immobilized endo-beta-n-acetylglucosaminidase a.a procedure for the enzymatic synthesis of neoglycoenzymes is described. the gene encoding endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) was overexpressed in escherichia coli as a fusion protein linked to glutathione s-transferase (gst). gst-endo-a fusion was extracted as a soluble protein. the fusion protein was purified to homogeneity with glutathione-sepharose 4b and showed transglycosylation activity toward high-mannose-type glycopeptides without removing the gst ...200010623587
phylogenetic and phenotypic diversity of 4-chlorobenzoate-degrading bacteria isolated from soils.twenty numerically dominant 4-chlorobenzoate (4-cba)-degrading bacteria were isolated from agricultural soils. the isolates were able to utilize 4-cba as a sole source of carbon and energy. a total of 65% of the isolates was identified to the species level by fatty acid methyl ester (fame) analysis, and the isolates were strains of micrococcus, pseudomonas, oerskovia, cellulomonas, and arthrobacter species. the chromosomal dna patterns of the isolates obtained by polymerase chain reaction (pcr) ...200010620719
characterization and radiation resistance of new isolates of rubrobacter radiotolerans and rubrobacter xylanophilus.in this study we characterized new strains of the slightly thermophilic species rubrobacter radiotolerans and the thermophilic species rubrobacter xylanophilus, both of which were previously represented only by the type strains isolated, respectively, from japan and the united kingdom. the new isolates were recovered from two hot springs in central portugal after gamma irradiation of water and biofilm samples. we assessed biochemical characteristics, performed dna-dna hybridization, and carried ...199910591012
Displaying items 1001 - 1100 of 2332