mannopine and mannopinic acid as substrates for arthrobacter sp. strain mba209 and pseudomonas putida na513.the characteristics of mannopine and mannopinic acid utilization by agrobacterium tumefaciens b6s3, arthrobacter sp. strain mba209, and pseudomonas putida na513 were studied. strain b6s3 utilized the four mannityl opines, mannopine, mannopinic acid, agropine, and agropinic acid. it also utilized several mannityl opine analogs, which were modified in either the sugar or the amino acid moiety. it utilized mannopine more rapidly after preincubation on mannopine, mannopinic acid, or glutamine than a ...19911902209
antagonistic effect of coryneform bacteria from red smear cheese against listeria species.a total of 187 coryneform bacteria were isolated from red smear and screened for inhibitory effects against 16 strains of listeria species. culture filtrates from brevibacterium linens (16 strains), arthrobacter nicotianae (4 strains) and arthrobacter nucleogenes (3 strains) showed clear zones of inhibition. the antagonistic effect was seen against 26 to 87% of 91 listeria strains tested. a. nicotianae and a. nucleogenes were more effective against listeria innocua and listeria ivanovii than aga ...19911909545
structural determination of d-mannans of pathogenic yeasts candida stellatoidea type i strains: timm 0310 and atcc 11006 compared to ifo 1397.the structures of the cell-wall d-mannans of pathogenic yeasts of candida stellatoidea type i strains, ifo 1397, timm 0310, and atcc 11006, were investigated by mild acid and, alkaline hydrolysis, by digestion with the arthrobacter gjm-1 strain exo-alpha-d-mannosidase, and by acetolysis. the modified d-mannans and their degradation products were studied by 1h- and 13c-n.m.r. analyses. d-manno-oligosaccharides released by acid treatment from the parent d-mannans were identified as the homologous ...19911954627
methylamine oxidase from arthrobacter p1 as a prototype of eukaryotic plasma amine oxidase and diamine oxidase.methylamine oxidase (maox) from gram-positive soil bacterium arthrobacter p1 catalyzes the oxidation of ch3nh2 to h2c = o and nh4+ via reduction of o2 to h2o2. past work indicates that maox is similar to mammalian plasma amine oxidase (pao) and diamine oxidase (dao), plant dao, and yeast peroxisomal amine oxidase (yao). all have mr congruent to 170,000 and are composed of 2 identical subunits, each of which contains 1 atom of cu(ii) and one molecule of quinonoid cofactor. herein, we report furth ...19901965196
choline oxidase, a catabolic enzyme in arthrobacter pascens, facilitates adaptation to osmotic stress in escherichia coli.choline oxidase (ec is a bifunctional enzyme that is capable of catalyzing glycine betaine biosynthesis from choline via betaine aldehyde. a gene (cox) encoding this enzyme in the gram-positive soil bacterium arthrobacter pascens was isolated and characterized. this gene is contained within a 1.9-kb fragment that encodes a polypeptide of approximately 66 kda. transfer of this gene to an escherichia coli mutant that is defective in betaine biosynthesis resulted in an osmotolerant phenot ...19911987142
direct evidence that ganglioside is an integral component of the thyrotropin receptor.gangliosides were extracted from purified human and porcine thyrotropin (tsh) receptors (tsh-r) and were detected by probing with an 125i-labeled sialic acid-specific lectin, limax flavus agglutinin. gangliosides copurified with human and porcine tsh-r migrated between monosialoganglioside gm1 and disialoganglioside gd1a. ceramide glycanase digestion of the purified human tsh-r-associated glycolipid confirmed its ganglioside nature. it was resistant to vibrio cholerae sialidase, which digests al ...19912000404
switching substrate preference of thermophilic xylose isomerase from d-xylose to d-glucose by redesigning the substrate binding pocket.the substrate specificity of thermophilic xylose isomerase from clostridium thermosulfurogenes was examined by using predictions from the known crystal structure of the arthrobacter enzyme and site-directed mutagenesis of the thermophile xyla gene. the orientation of glucose as a substrate in the active site of the thermophilic enzyme was modeled to position the c-6 end of hexose toward his-101 in the substrate-binding pocket. the locations of met-87, thr-89, val-134, and glu-180, which contact ...19912023950
metabolism of carbamate insecticides by resting cells and cell-free preparations of a soil bacterium, arthrobacter sp. 19912032002
occurrence of two structural types of mercury reductases among gram-positive bacteria.structural variants of mercury reductase containing the n-terminal domain, which is easily cleaved by trypsin, have been found in gram-positive bacteria with a low genomic g + c content (bacillus, staphylococcus and, possibly, some other genera). mercury reductases without the n-terminal domain and relatively resistant to limited proteolysis are typical for gram-positive bacteria with a high genomic g + c content (arthrobacter, citreobacterium, micrococcus, mycobacterium, rhodococcus). both type ...19912040434
biodegradation of refractory hydrocarbon biomarkers from petroleum under laboratory conditions.biomarkers are of great value in petroleum exploration because they provide essential information about the geological history of oils and source rocks. steranes are of particular importance as they can be related to naturally occurring precursors. these compounds generally experience intense biodegradation, however, which alters their original distribution and obscures the information that they carry regarding oil maturity and source material. in an attempt to identify the microorganisms respon ...19912052089
microbial metabolism of quinoline and related compounds. vi. degradation of quinaldine by arthrobacter sp.quinaldine catabolism was investigated with the bacterial strain arthrobacter sp., which is able to grow aerobically in a mineral salt medium with quinaldine as sole source of carbon, nitrogen and energy. the following degradation products of quinaldine were isolated from the culture fluid and identified: 1h-4-oxoquinaldine, n-acetylisatic acid, n-acetylanthranilic acid, anthranilic acid, 3-hydroxy-n-acetylanthranilic acid and catechol. 3-hydroxy-n-acetylanthranilic acid was not further metaboli ...19902076195
refinement of glucose isomerase from streptomyces albus at 1.65 a with data from an imaging plate.the structure of 'metal-free' glucose isomerase of streptomyces albus strain number yt atcc 21132 has been analysed and refined at 1.65 a. the space group is i222, with cell dimensions a = 93.9 (1), b = 99.7 (1) and c = 102.9 (1) a, and there is one monomer of the tetrameric molecule per asymmetric unit. the data were recorded from two crystals of the protein using synchrotron radiation from the embl beamline x11 at desy, hamburg. data were recorded with an imaging plate scanner designed and bui ...19902085424
chlorinated biphenyl mineralization by individual populations and consortia of freshwater bacteria.comparative studies were performed to investigate the contribution of microbial consortia, individual microbial populations, and specific plasmids to chlorinated biphenyl biodegradation among microbial communities from a polychlorinated biphenyl-contaminated freshwater environment. a bacterial consortium, designated lps10, was shown to mineralize 4-chlorobiphenyl (4cb) and dehalogenate 4,4'-dichlorobiphenyl. the lps10 consortium involved three isolates: pseudomonas testosteroni (lps10a), which m ...19902117875
[molecular cloning and expression of a dextranase gene from arthrobacter in streptococcus sanguis].the gene coding for a dextranase activity of arthrobacter cb-8, named dex gene, was isolated and cloned into escherichia coli and into streptococcus sanguis. the gene library was screened by transparent halo formation around the colonies grown on agar medium containing blue dextran. dna fragment consisting of about 3,200 base pairs was prepared for further cloning procedures. dextranase activity was detected in the periplasmic space of e. coli clones, using puc19, pva 838 and their derivatives. ...19902135413
new ganglioside analogs that inhibit influenza virus sialidase.synthetic thioglycoside-analogs of gangliosides such as neu5ac alpha(2-s-6)glc beta(1-1)ceramide (1) and the gm3 analog neu5ac alpha(2-s-6)gal beta(1-4)glc beta(1-1)ceramide (2), competitively inhibited gm3 hydrolysis by the sialidase of different subtypes of human and animal influenza viruses with an apparent ki value of 2.8 x 10(-6) and 1.5 x 10(-5) m, respectively. the inhibitory activity of the ganglioside gm4 analog [neu5ac alpha(2-s-6)gal beta(1-1)ceramide (3)], in which the glucose of 1 w ...19902136350
sa11 rotavirus is specifically inhibited by an acetylated sialic acid.bovine salivary mucin (bsm) inhibits rotavirus replication in vitro and in vivo. the inhibitory effect of bsm in vitro is abolished by arthrobacter ureafaciens neuraminidase but not by clostridia perfringens neuraminidase; it is abolished by mild base deacetylation but not by influenza c acetylesterase. the data suggest that sa11 rotavirus binds to a specific sialic acid structure on bsm different from the sialic acids recognized by other viruses.19902153181
reductive trapping of substrate to methylamine oxidase from arthrobacter p1.methylamine oxidase (ec from arthrobacter p1 was inactivated by nacnbh3 in the presence of [14c]benzylamine, leading to the incorporation of 1 mol of radiolabeled substrate/mol of enzyme subunit at complete inactivation. by contrast, no labeling of enzyme was observed using [3h]nacnbh3 as reductant. these results are analogous to those previously reported for the eukaryotic enzyme, bovine serum plasma amine oxidase [(1987) j. biol. chem. 262, 962-965]. the observed pattern of labeling i ...19902155832
an examination of proton translocation and energy conservation during heterotrophic nitrification.whether selected heterotrophic nitrifiers, as do the autotrophs, conserve energy during the oxidation of their nitrogenous substrates was studied. the examination of proton translocation of four different bacterial nitrifiers capable of pyruvic oxime [(po), ch3-c(noh)-cooh] nitrification and by an nh4+ oxidizing arthrobacter sp. was initiated. three of the po nitrifying bacteria, all pseudomonads, oxidize hydroxylamine (nh2oh) at a greater rate than po and yielded only stoichiometric protons whe ...19902157622
growth of group a rotaviruses in a human liver cell line.recent observations in children with rotavirus gastroenteritis and in infant mice given rotavirus vaccine by oral administration suggest that this well-known gastrointestinal pathogen may infect the liver. to examine this possibility, the susceptibility of hep g2 cells to infection with a variety of rotavirus strains was tested. these cells were used because they are considered to be well differentiated and exhibit many liver-specific functions. the hep g2 cells supported the growth of the simia ...19902170264
acii, a unique restriction endonuclease from arthrobacter citreus which recognizes 5' ccgc 3'. 19902170952
structural study of cell wall phosphomannan of candida albicans nih b-792 (serotype b) strain, with special reference to 1h and 13c nmr analyses of acid-labile oligomannosyl residues.chemical structures of manno-oligosaccharides, from biose to heptaose, released from the phosphomannan of candida albicans nih b-792 strain (serotype b) by mild acid hydrolysis were investigated. the results of 1h nmr, 13c nmr, and fast atom bombardment mass spectrometry analyses confirmed that these manno-oligosaccharides belong to a homologous beta-1,2-linked series. although chemical shifts of 1h nmr patterns of these oligosaccharides were considerably too complicated to be assigned, their 13 ...19902181936
catalytic mechanism of xylose (glucose) isomerase from clostridium thermosulfurogenes. characterization of the structural gene and function of active site histidine.the gene coding for thermophilic xylose (glucose) isomerase of clostridium thermosulfurogenes was isolated and its complete nucleotide sequence was determined. the structural gene (xyla) for xylose isomerase encodes a polypeptide of 439 amino acids with an estimated molecular weight of 50,474. the deduced amino acid sequence of thermophilic c. thermosulfurogenes xylose isomerase displayed higher homology with those of thermolabile xylose isomerases from bacillus subtilis (70%) and escherichia co ...19902229064
mechanism of enzymatic dehalogenation of pentachlorophenol by arthrobacter sp. strain atcc 33790.pentachlorophenol (pcp) dehalogenase from arthrobacter sp. strain atcc 33790 converts pcp to tetrachlorohydroquinone. in labeling experiments with h(2)18o or 18o2, only with h(2)18o was labeled product found. however, unlabeled tetrachlorohydroquinone became labeled after incubation with the enzyme in h(2)18o. therefore, distinction between an oxygenolytic or a hydrolytic dehalogenation mechanism for the pcp dehalogenase is not possible.19902254286
soluble and cell-associated haemagglutinins of helicobacter (campylobacter) pylori.some plate-grown strains of helicobacter (campylobacter) pylori that were harvested into phosphate-buffered saline and left for 1 h released soluble haemagglutinins. these caused high-titre agglutination of human and guinea-pig erythrocytes, whereas chicken, sheep and bovine erythrocytes were agglutinated at various titres. six of 10 strains which had been subcultured repeatedly did not possess soluble haemagglutinins. slide agglutination of bacterial suspensions demarcated the strains into two ...19902258915
utilization of acrylonitrile by bacteria isolated from petrochemical waste waters.a bacterium, utilising acrylonitrile as a sole source of carbon and nitrogen, was isolated from indian petrochemical corporation limited (ipcl) waste waters and identified as arthrobacter sp. this strain could also utilize acetonitrile, acetamide and acrylamide individually as a source of carbon and nitrogen. the metabolic studies with the whole cells indicated the sequential conversion of the nitrile to the respective amide and then to the respective acid and ammonia. the rate of nitrile hydrol ...19902279769
methylamine oxidase from arthrobacter p1. 19902280707
observations of reaction intermediates and the mechanism of aldose-ketose interconversion by d-xylose isomerase.crystallographic studies of d-xylose isomerase (d-xylose ketol-isomerase, ec incubated to equilibrium with substrate/product mixtures of xylose and xylulose show electron density for a bound intermediate. the accumulation of this bound intermediate shows that the mechanism is a non-michaelis type. carrell et al. [carrell, h. l., glusker, j. p., burger, v., manfre, f., tritsch, d. & biellmann, j.-f. (1989) proc. natl. acad. sci. usa 86, 4440-4444] and the present authors studied crystals ...19902304904
mechanism for aldose-ketose interconversion by d-xylose isomerase involving ring opening followed by a 1,2-hydride shift.the active site and mechanism of d-xylose isomerase have been probed by determination of the crystal structures of the enzyme bound to various substrates, inhibitors and cations. ring-opening is an obligatory first step of the reaction and is believed to be the rate-determining step for the aldose to ketose conversion. the structure of a complex with a cyclic thio-glucose has been determined and it is concluded that this is an analogue of the michaelis complex. at -10 degrees c substrates in cry ...19902319597
a repeated decapeptide motif in the c-terminal domain of the ribosomal rna methyltransferase from the erythromycin producer saccharopolyspora of the primary structure of the ribosomal rna n-methyltransferase that confers self-resistance on the erythromycin-producing bacterium saccharopolyspora erythraea has confirmed the presence of a c-terminal domain containing extensive repeat sequences. nine tandem repeats can be discerned, with a decapeptide consensus sequence ggrx(h/r)gdrrt, although no single residue is wholly invariant. this highly polar, potentially flexible domain, which is predicted to adopt either a random coil ...19902335200
a survey of the microflora of raw and pasteurized milk and the sources of contamination in a milk processing plant in addis ababa, ethiopia.the microorganisms present in raw and pasteurized milk and the sources of contamination in the milk after it had arrived at the processing plant in addis ababa were studied. the lowest count registered for raw milk samples was 4 x 10(7) cfu/ml while the highest was 1 x 10(9) cfu/ml. pasteurized milk had mesophilic aerobic counts of 7 x 10(5) cfu/ml as it left the pasteurizing unit, but the population increased 2- to 4-fold as a result of subsequent contamination. of the total counts in raw milk, ...19902345191
rapid detection of extended ganglio-series gangliosides with terminal galnac beta 1-4gal sequence on high performance thin layer chromatography plates.the mouse monoclonal antibody 2d4, which recognizes the terminal galnac beta 1-4gal-disaccharide of ggose3cer and ggose5cer, was used for the detection of ganglio-series gangliosides. the method involves separation of gangliosides on thin layer chromatography plates, followed by silica gel fixation, arthrobacter ureafaciens neuraminidase treatment and final immunostaining of desialylated gangliosides with the monoclonal antibody 2d4. both neuraminidase and the hybridoma 2d4 producing the specifi ...19902350601
effect of organic amendments on bacterial multiplication in lake cayuga lake water amended with 30 micrograms of glucose or amino acids per ml, an added strain of pseudomonas fluorescens and indigenous bacteria grew extensively, pseudomonas sp. b4 and two rhizobia multiplied at a moderate extent, and introduced escherichia coli and klebsiella pneumoniae multiplied but to only a slight degree. the amendments did not enhance growth of micrococcus flavus and arthrobacter citreus, and an asporogenous strain of bacillus subtilis decreased in numbers. the pseudo ...19902372214
functional analysis of the 5' regulatory region and the uug translation initiation codon of the arthrobacter oxidans 6-hydroxy-d-nicotine oxidase gene.a functional analysis of the arthrobacter oxidans 6-hydroxy-d-nicotine oxidase (6-hdno) gene promoter (-35 region ttgaca and -10 region tatcaat) and the uug translation start codon was performed using site-directed mutagenesis. deletion of the c residue from the -10 promoter region or mutations introduced upstream of the -10 region resulted in an increased 6-hdno expression in escherichia coli cells in vivo and in both e. coli and a. oxidans coupled transcription-translation systems in vitro. fr ...19902381422
characterization of phi ga1, an inducible phage particle from brevibacterium flavum.eighteen related strains of arthrobacter, brevibacterium and corynebacterium were used as indicator strains in an attempt to isolate corynephages from a large number of soils and from waste-water samples. although no phages capable of producing plaques were isolated, one of the indicator strains used, brevibacterium flavum atcc 14067, was lysogenic for the inducible phage phi ga1. this phage was not observed to form plaques on any of the strains tested. phi ga1 is of b1-morphotype with a linear ...19902391491
different types of dienelactone hydrolase in 4-fluorobenzoate-utilizing bacteria.of various benzoate-utilizing bacteria tested, alcaligenes eutrophus 335, a. eutrophus h16, a. eutrophus jmp222, a. eutrophus jmp134, alcaligenes strain a7, and pseudomonas cepacia were able to grow with 4-fluorobenzoate as the sole source of carbon and energy. p. cepacia also utilizes 3-fluorobenzoate. except for a. eutrophus jmp134, which is known to grow with 2,4-dichlorophenoxyacetate and 3-chlorobenzoate (r. h. don and j. m. pemberton, j. bacteriol. 145:681-686, 1981), the strains were unab ...19902394679
isolation and characterization of influenza c virus inhibitor in rat serum.two hemagglutination inhibitors for influenza c virus were isolated from pooled sera of normal rats by sequential chromatography on blue sepharose cl 6b, ultrogel aca 22, and deae-cellulose. the two inhibitors were identified as alpha 1-macroglobulin and murinoglobulin by comparison with the authentic samples. these inhibitors abolished the hemagglutination by influenza c virus strains but did not affect the hemagglutination by influenza a and b virus strains. hemagglutination inhibition activit ...19852416143
biochemical properties of n-methylamides of sialic acids in gangliosides.a simple and rapid method for the preparation of n-methylamides ( - conhch3) of sialic acids in gangliosides and biochemical properties of the modified gangliosides are described. the sialic acid carboxyl groups of gangliosides were esterified with ch3i-dimethylsulfoxide, followed by heating with monomethylamine. the modified gangliosides were chemically identified by tlc, ir spectroscopy, glc-mass spectrometry and nmr spectroscopy. the n-methylamide derivative of gm1 produced a high titer igg a ...19862420784
production of organic acids by bacteria isolated from soil, rhizosphere and mycorrhizosphere of pine (pinus sylvestris l.).the bacteria studied released into the medium ten to eleven organic acids. soil organisms excreted mainly pyruvic and alpha-ketoglutaric acids, while strains from the root zone--gluconic acid and unidentified uronic acid (y2). mean indices of total production of the organic acids by bacteria were in the following order: rhizosphere less than soil less than mycorrizosphere. bacteria from the root zone released into the medium very large amounts of pyruvic, gluconic, and uronic (y2) acids--in some ...19852421547
metabolism of glyphosate in an arthrobacter sp. glp-1.the metabolism of glyphosate [n-(phosphonomethyl)glycine] in a bacterium tentatively identified as an arthrobacter sp., capable of growth on this herbicide as its sole phosphorus source, has been investigated using solid-state nmr techniques as well as radiotracer analysis. the pathway involves the conversion of glyphosate to glycine, a c1 unit and phosphate. the phosphonomethyl carbon is specifically incorporated into the amino acids serine, cysteine, methionine, and histidine, as well as into ...19872439330
transformation of arthrobacter and studies on the transcription of the arthrobacter erma gene in streptomyces lividans and escherichia coli.we report the development of a plasmid-mediated transformation system for arthrobacter sp. nrrlb3381, using the streptomyces cloning vector pij702. our procedure gives a transformation frequency of 10(3)/micrograms of plasmid dna. in addition we have explored the expression of the arthrobacter erma gene in streptomyces lividans and escherichia coli, and shown that the erma promoter is recognized in s. lividans not e. coli. the relationship between arthrobacter, streptomyces and e. coli promoters ...19872443127
nucleotide sequences of 5s ribosomal rnas of arthrobacter oxydans, arthrobacter polychromogenes, arthrobacter globiformis and 'brevibacterium helvolum'. 19882457874
dna probes with different specificities from a cloned 23s rrna gene of micrococcus luteus.a 7500 bp psti restriction fragment of chromosomal dna from micrococcus luteus containing a 23s rrna gene was cloned in vector phe3 in e. coli rr 28 (the recombinant plasmid was designated par1). a recombinant phage (par5) hybridizing to all eubacteria tested was constructed by shotgun subcloning of the psti fragment in phage m13mp8. further subcloning of the fragments of the 23s rrna gene in the vectors ptz18r and ptz19r using selected restriction sites of the gene enabled us to select cloned f ...19882462009
the sulfated polysaccharide-peptidoglycan complex potently inhibits embryonic angiogenesis and tumor growth in the presence of cortisone combination with cortisone acteate, the sulfated polysaccharide (sp)-peptidoglycan (pg) complex produced by an arthrobacter species was found to inhibit both embryonic angiogenesis of chick chorioallantoic membrane (cam) and growth of solid sarcoma 180 tumor in mice. three fractions obtained from the sp-pg complex by gel filtration showed a great difference in the inhibitory effect on angiogenesis of the cam, whereas in ex vivo study such a difference was reduced. of the three fractions, sp-p ...19882463087
antitumor effects of an antiangiogenic polysaccharide from an arthrobacter species with or without a steroid.a sulfated polysaccharide-peptidoglycan complex, ds-4152, isolated from the culture supernatant of an arthrobacter species inhibited angiogenesis and tumor growth and enhanced the antiangiogenic activity of 11 steroid hormones by 2 to 100 times. in the presence of cortisone acetate or tetrahydro s, ds-4152 suppressed chick chorioallantoic membrane angiogenesis and murine tumor m5076 cell-induced s.c. angiogenesis. the antitumor effects of ds-4152 administered in combination with a steroid whose ...19892479471
expression of the arthrobacter viscosus penicillin g acylase gene in escherichia coli and bacillus subtilis.the penicillin g acylase gene cloned from arthrobacter viscosus 8895gu was subcloned into vectors, and the recombinant plasmids were transferred into escherichia coli or bacillus subtilis. both e. coli and b. subtilis transformants expressed the a. viscosus penicillin g acylase. the enzyme activity was found in the intracellular portion of the e. coli transformants or in the cultured medium of the b. subtilis transformants. penicillin g acylase production in the b. subtilis transformants was 7.2 ...19892504107
molecular relationship of chromosomal genes encoding biphenyl/polychlorinated biphenyl catabolism: some soil bacteria possess a highly conserved bph operon.all the genes we examined that encoded biphenyl/polychlorinated biphenyl (pcb) degradation were chromosomal, unlike many other degradation-encoding genes, which are plasmid borne. the molecular relationship of genes coding for biphenyl/pcb catabolism in various biphenyl/pcb-degrading pseudomonas, achromobacter, alcaligenes, moraxella, and arthrobacter strains was investigated. among 15 strains tested, 5 pseudomonas strains and one alcaligenes strain possessed the bphabc gene cluster on the xhoi ...19892507526
[hydrophilic-hydrophobic properties of microorganisms under various culturing conditions].the index of hydrophobicity and the hydrophilic-hydrophobic properties of seven microbial cultures were determined by studying their adhesion to n-hexadecane. the index of hydrophobicity was shown to be a stable characteristic of a culture grown in media with different carbon sources. as was found for escherichia coli k-12 and acinetobacter calcoaceticus k-9 whose hydrophobicity indicates were quite different, the character of cell hydration was virtually independent of the growth phase and did ...19892511395
13c, 15n, and 31p nmr studies on 6-hydroxy-l-nicotine oxidase from arthrobacter oxidans.the interaction between the apoprotein of 6-hydroxy-l-nicotine oxidase from arthrobacter oxidans and the prosthetic group fad has been investigated by 13c, 15n, and 31p nmr techniques. the fad prosthetic group was selectively enriched in 13c and 15n isotopes by adding isotopically labeled riboflavin derivatives to the growth medium of riboflavin-requiring mutant cells. in the oxidized state the chemical shift of the c(7) and c(8) atoms indicates that the xylene moiety of the isoalloxazine ring i ...19892540800
comparison of human, simian, and bovine rotaviruses for requirement of sialic acid in hemagglutination and cell adsorption.human rotaviruses (wa, kun, mo) showed hemagglutination (ha) only with fixed 1-day-old chicken erythrocytes, and their ha activities were completely destroyed by trypsin activation of virions. simian sa-11 and bovine ncdv had ha activities not only against fixed erythrocytes but also against fresh erythrocytes from various species. their ha activities against fixed erythrocytes were also inhibited by trypsin activation, but those against fresh erythrocytes were not. neuraminidase treatment of fi ...19892549710
nitrogen metabolism in the facultative methylotroph arthrobacter p1 grown with various amines or ammonia as nitrogen sources.the metabolism of trimethylamine (tma) and dimethylamine (dma) in arthrobacter p1 involved the enzymes tma monooxygenase and trimethylamine-n-oxide (tma-no) demethylase, and dma monooxygenase, respectively. the methylamine and formaldehyde produced were further metabolized via a primary amine oxidase and the ribulose monophosphate (rump) cycle. the amine oxidase showed activity with various aliphatic primary amines and benzylamine. the organism was able to use methylamine, ethylamine and propyla ...19892589850
purification and properties of neuraminidase isozymes in arthrobacter ureafaciens arthrobacter ureafaciens mutant (m1057) capable of producing neuraminidase constitutively was isolated by ntg mutagenesis from a. ureafaciens kms 3663. four molecular species (l, m1, m2, and s) of neuraminidase isozymes were homogeneously purified from the mutant and parent strains by means of deae-cellulose, affinity chromatography, ammonium sulfate precipitation, chromatofocusing, and ultrogel aca44 gel filtration. the molecular weights of l, m1, m2, and s isozymes were shown to be approxim ...19892628425
binding of fad to 6-hydroxy-d-nicotine oxidase apoenzyme prevents degradation of the holoenzyme.expression of the 6-hydroxy-d-nicotine oxidase (6-hdno) gene from arthrobacter oxidans cloned into escherichia coli showed a marked temperature-dependence. transformed e. coli cells grown at 30 degrees c exhibited a several-fold higher 6-hdno activity than did cells grown at 37 degrees c. this effect did not depend on the promoter used for expression of the cloned gene in e. coli, nor was it an effect of 6-hdno mrna instability at 37 degrees c. studies performed in vivo and in vitro revealed tha ...19892649085
crystallisation and preliminary analysis of glucose isomerase from streptomyces albus.the glucose isomerase of streptomyces albus has been crystallised from a dilute solution of magnesium chloride buffered at a ph of 6.8-7.0. the crystals are in the space group i222 with cell dimensions a = 93.9 a, b = 99.5 a and c = 102.9 a. there is one monomer of the tetrameric molecule per asymmetric unit of the crystal and the packing density is 2.93 a3.da-1. the tetramer sits on the 222 symmetry point of the crystal. native data have been recorded to a resolution of 1.9 a and the crystals d ...19892651156
covalent cofactor binding to flavoenzymes requires specific effectors.modification by covalent fad attachment to a histidine residue via an 8 alpha-(n3-histidyl)-riboflavin linkage occurs in several flavoenzymes. among them is 6-hydroxy-d-nicotine oxidase (6-hdno) of arthrobacter oxidans and the flavoprotein subunits of the fumarate reductase and succinate dehydrogenase complex of escherichia coli and other bacterial and eukaryotic cells. we found that 6-hdno holoenzyme formation from apo-6-hdno, monitored by [14c]fad incorporation and increase in enzyme activity, ...19892659351
structural analysis of phospho-d-mannan-protein complexes isolated from yeast and mold form cells of candida albicans nih a-207 serotype a strain.the immunochemical properties between phospho-d-mannan-protein complexes of yeast (y) and mycelial (m) forms of candida albicans nih a-207 (serotype a) strain were compared. hydrolysis of the y-form complex gave a mixture of beta-(1----2)-linked d-mannooligosaccharides consisting mainly of tri- and tetra-ose, whereas the m-form complex gave preponderantly d-mannose. the antiserum against y-form cells exhibited a lower reactivity with the m-form than with the y-form complex, whereas the antiserum ...19892663154
structural study of phosphomannan of yeast-form cells of candida albicans j-1012 strain with special reference to application of mild acetolysis.structural analysis of the phosphomannan isolated from yeast-form cells of a pathogenic yeast, candida albicans j-1012 strain, was conducted. treatment of this phosphomannan (fr. j) with 10 mm hcl at 100 degrees c for 60 min gave a mixture of beta-1,2-linked manno-oligosaccharides, from tetraose to biose plus mannose, and an acid-stable mannan moiety (fr. j-a), which was then acetolyzed by means of an acetolysis medium, 100:100:1 (v/v) mixture of (ch3co)2o, ch3cooh, and h2so4, at 40 degrees c fo ...19892665649
assay for sialidase using erythrocytes and peroxidase-labeled peanut lectin.a rapid and sensitive sialidase assay method based on peroxidase-labeled peanut lectin (pna) binding to desialylated erythrocyte is described. formalinized sheep erythrocytes were used both as a stable substrate for sialidase and as a target for the lectin. in the case of sialidases from vibrio cholerae and arthrobacter ureafaciens, a linear relationship was observed between the amount of peroxidase-labeled pna bound to erythrocytes and the enzyme amount. binding of the lectin to sialidase-treat ...19892688936
two structural types of mercury reductases and possible ways of their evolution.structural differences have been revealed among mercury reductases of immunologically unrelated types from gram-positive bacteria: enzymes of one immunological type have a molecular mass of 62-69 kda and seem to contain an n-terminal extension of 5-15 kda, which is easily cleaved by trypsin and chymotrypsin; enzymes of the other immunological type have a molecular mass of 52-57 kda and are resistant to proteolysis. the existence of at least two different lines in the evolution of mercury reducta ...19892714439
inhibition of mouse liver sialidase by the root of scutellaria baicalensis.of 266 chinese crude drugs, the hot water extract from the root of scutellaria baicalensis showed potent mouse liver sialidase inhibitory activity; in addition, wogonin, wogonin glucuronide, baicalein, and baicalin were identified as the inhibitors. these flavonoids showed almost the same inhibitory activity when 50-125 micrograms/ml doses of the samples were used for the assay, while wogonin and baicalein showed a more potent activity than wogonin glucuronide and baicalin at the lower concentra ...19892717686
biodegradation of crude oils.petroleum from well sites in the gifhorn trough (lower saxony, nw-germany) and the maracaibo basin (venezuela) contained various types of microorganisms capable of degrading crude oils. genetically related oils were inoculated with the isolated microorganisms and the degradation of the oils was followed by chromatographic techniques. parameters important for the reactions (ph, supply of oxygen, nitrogen and phosphorus, reaction medium) were monitored and optimized. the degradation of n-alkanes w ...19892727641
a new nad+-dependent opine dehydrogenase from arthrobacter sp. strain 1c.a new nad+-dependent opine dehydrogenase was purified to homogeneity from arthrobacter sp. strain 1c isolated from soil by an enrichment culture technique. the enzyme has a molecular weight of about 70,000 and consists of two identical subunits with molecular weights of about 36,000. the enzyme catalyzed a reversible oxidation-reduction reaction of opine-type secondary amine dicarboxylic acids. in the oxidative deamination reaction, the enzyme was active toward unusual opines, such as n-[1-r-(ca ...19892753861
structures of d-xylose isomerase from arthrobacter strain b3728 containing the inhibitors xylitol and d-sorbitol at 2.5 a and 2.3 a resolution, respectively.the structures of d-xylose isomerase from arthrobacter strain b3728 containing the polyol inhibitors xylitol and d-sorbitol have been solved at 2.5 a and 2.3 a, respectively. the structures have been refined using restrained least-squares refinement methods. the final crystallographic r-factors for the d-sorbitol (xylitol) bound molecules, for 43,615 (32,989) reflections are 15.6 (14.7). the molecule is a tetramer and the asymmetric unit of the crystal contains a dimer, the final model of which, ...19892769749
sialidase from different sources compared for electrophoretically separating serum alkaline phosphatase fractions from liver and bone.we compared sialidase (neuraminidase; ec from vibrio cholerae, clostridium perfringens, and arthrobacter ureafaciens, seeking to improve the electrophoretic separation of the liver and bone isoenzymes of alkaline phosphatase (ec on cellulose acetate membranes. resolution is decisively determined by the type and activity of sialidase used in the preincubation of serum sample. sialidase from arthrobacter ureafaciens is not suited for this method. for optimal separation of the tw ...19892776324
enzymatic dehalogenation of pentachlorophenol by extracts from arthrobacter sp. strain atcc 33790.arthrobacter sp. strain atcc 33790 was grown with pentachlorophenol (pcp) as the sole source of carbon and energy. crude extracts, which were prepared by disruption of the bacteria with a french pressure cell, showed no dehalogenating activity with pcp as the substrate. after sucrose density ultracentrifugation of the crude extract at 145,000 x g, various layers were found in the gradient. one yellow layer showed enzymatic conversion of pcp. one chloride ion was released per molecule of pcp. the ...19892793827
[microbiological dehydrogenation of intermediate of fluocinanide acetate].both compound i and ii are intermediates in fluocinanide acetate synthesis. i could be dehydrogenated to ii in 62% approximately 63% yields by arthrobactor simplex no. a-1, which was selected in our laboratory. when concentration of i was 0.1%, it was transformed so fast that ii could not be accumulated. when concentration was increased to 0.2%, four intermediates iv, v, vi and vii were formed in addition to a little amount of product ii. when concentration of substrate i was increased to 0.5% a ...19892801119
homology and distribution of co dehydrogenase structural genes in carboxydotrophic bacteria.the 17 (s), 30 (m) and 87 kda (l) subunits of co dehydrogenases from the co-oxidizing bacteria pseudomonas carboxydoflava, pseudomonas carboxydohydrogena and pseudomonas carboxydovorans om5 were isolated and purified. the n-terminal sequences of same subunits from different bacteria showed distinct homologies. dot blot hybridization employing oligonucleotide probes derived from the sequences of the s-subunit of p. carboxydovorans om5 and the m-subunit of p. carboxydohydrogena and dna of the plas ...19892818128
asni: a novel class ii restriction endonuclease from arthrobacter sp., strain n-cm, recognizing 5'-at/taat-3'.a new class ii restriction endonuclease, asni, with a novel sequence specificity was isolated from the gram-positive eubacterium arthrobacter species, strain n-cm. asni recognizes the unambiguously defined palindromic hexanucleotide (formula: see text) consisting of a- and t-residues. the novel enzyme in the presence of mg2+ cleaves specifically both strands as indicated by the arrows. the staggered cuts generate 5'-protruding ends with single-stranded 5'-ta-3' dinucleotide extensions. the novel ...19882841156
arthrobacter viscosus dna is modified at gatc sequence.arthrobacter viscosus dna was resistance to digestion by restriction enzymes that are sensitive to methylation of the cytosine residue (but not of adenine) within the gatc recognition sequence. restriction enzymes sensitive to methylation of cytosine in other recognition sequences were not affected. a. viscosus dna thus appeared to contain methylated cytosine specifically at the gatc sequence.19882844183
a host-vector system for an arthrobacter efficient host-vector system has been developed for an industrial strain of arthrobacter sp. (nrrl b3728)used for glucose isomerase production. protoplasts of arthrobacter were generated by treating the cells with 0.5 mg lysozyme ml(-1) for 60 min in a solution containing 0.5 m-sucrose. around 30% of the protoplasts regenerated on agar containing 0.5 m-sodium succinate as osmotic stabilizer. three hybrid vectors, pbl2100, pcg1100 and pcg2100, were constructed by combining the escherichia coli ...19882846755
synthesis of p-nitrophenyl 5-acetamido-3,5-dideoxy-alpha-d-glycero-d-galacto-2-nonulopyranosid onic acid, a chromogenic substrate for sialidases. 19872885090
siderophore production by salmonella typhi.this study was initiated to determine the mechanism of iron-uptake in salmonella typhi. when stressed for iron, microorganisms produce siderophores to obtain the necessary nutrient. generally two types of siderophores exist: the phenolate-type predominantly produced by bacteria and the hydroxamate-type commonly secreted by fungi. results of this investigation showed that s. typhi produced siderophores of the phenolate-type since culture supernatant of the organism grown under iron-deprivation su ...19882962581
iron acquisition by haemophilus influenzae.the mechanisms for acquisition of iron by haemophilus influenzae and their role in pathogenesis are not known. heme and nonheme sources of iron were evaluated for their effect on growth of type b and nontypable strains of h. influenzae in an iron-restricted, defined medium. all 13 strains acquired iron from heme, hemoglobin, hemoglobin-haptoglobin, and heme-hemopexin. among nonheme sources of protein-bound iron, growth of h. influenzae was enhanced by partially saturated human transferrin but no ...19882964410
[combined immobilized cultures producing fibrinolytic proteinases].the authors obtained combined immobilised systems composed of a culture producing fibrinolytic proteinases and a stimulating strain. the optimal ratio between the two cultures in gel was selected at a high starting cell density. highly stable immobilised cultures were produced by growing the cells in gel particles. the interrelationship of the partners was studied in the binary immobilised culture. the biosynthetic activity of the system fell down to the level of a monoculture when the cells of ...19882977814
plasmid pao1 of arthrobacter oxidans encodes 6-hydroxy-d-nicotine oxidase: cloning and expression of the gene in escherichia coli.the 160 kb plasmid pao1 from arthrobacter oxidans (brandsch and decker 1984) was subcloned in escherichia coli with the aid of the plasmid vectors pur222 and pbr322. screening of the recombinant clones for enzyme activity revealed that the flavoenzyme 6-hydroxy-d-nicotine oxidase (6-hdno), one of the enzymes of the nicotine-degradative pathway in a. oxidans, is encoded on pao1. immunoprecipitation of 35s-methionine-labelled e. coli cells with 6-hdno-specific antiserum and expression of recombina ...19863007941
evidence for the functional role of monosialoganglioside gm1 in synaptic transmission in the rat hippocampus.the hippocampal slices were incubated with compounds which hydrolyze, modify or bind with sialic acid containing molecules. the efficiency of synaptic transmission was tested in the presence of these compounds. the size of the evoked extracellularly recorded potential following schaffer collateral stimulation was used as an indicator of synaptic transmission efficiency. sodium periodate (10 mm) and sodium perchlorate (59.2 mm) evoked a reversible (after washout) decrease in the size of the popul ...19863008944
structural characteristics of the corynebacterium lilium bacteriophage cl31.bacteriophage cl31 was isolated on a corynebacterium lilium strain. out of 30 strains tested, only cl31 was able to form plaques on corynebacterium glutamicum atcc 13287, brevibacterium lactofermentum atcc 21086, and arthrobacter sp. strain si55, but at a very low frequency. this phage belongs to group b of bradley's classification (d. e. bradley, bacteriol. rev. 31:230-314; 1967). its head is 53 nm in diameter, and its tail is 396 nm in length. the phage capsid contains three major proteins, of ...19873033280
covalent flavinylation of 6-hydroxy-d-nicotine oxidase analyzed by partial deletions of the gene.the expression of the enzymatically active 6-hydroxy-d-nicotine oxidase (6-hdno) from arthrobacter oxidans requires the covalent attachment of fad to the polypeptide chain. how this modification takes place and at what time during the synthesis of the polypeptide is not known. we investigated the possibility of cotranslational flavinylation by generating various deletions of the 6-hdno gene carried on appropriate plasmid vectors. the polypeptides expressed from these plasmids were analyzed for t ...19873036509
[identification of the causative agent of allergic alveolitis in a selected group of patients by using microbiological and immunological methods]. 19883043388
the phosphoenolpyruvate:sugar phosphotransferase system in gram-positive bacteria: properties, mechanism, and regulation.this review consists of three major sections. the first and largest section reviews the protein constituents and known properties of the phosphotransferase systems present in well-studied gram-positive bacteria. these bacteria include species of the following genera: (1) staphylococcus, (2) streptococcus, (3) bacillus, (4) lactobacillus, (5) clostridium, (6) arthrobacter, and (7) brochothrix. the properties of the different systems are compared. the second major section deals with the regulation ...19883060316
are 'light-derepressible' genes controlled by metal-protein complexes? 19883072697
on the influence of different growth conditions to the resistance of some methylotrophic bacteria to aldehydes.the resistance to formaldehyde of several facultatively methylotrophic bacteria has been investigated. the mic-values were in the range of formaldehyde concentrations used for preservation purposes. the resistance could be explained partly by the action of aldehyde dehydrogenase found in two of the strains and by the development of a penetration barrier by the cell envelopes described formerly.19863092505
cloning and expression in escherichia coli of the gene for an arthrobacter beta-(1----3)-glucanase.when inserted in the correct orientation at the bamhi site of plasmid yrp7, an 8.6-kilobase bamhi fragment of arthrobacter sp. strain ycwd3 dna gave escherichia coli hb101 cells harboring the recombinant plasmid pbx20 the ability to lyse bakers' yeast cell walls or bakers' yeast glucan in agar medium. an extract of the transformed e. coli cells contained an endo-beta-(1----3)-glucanase with the same activity pattern as that of glucanase i produced by arthrobacter sp. strain ycwd3. although part ...19863096974
[esterase activity of hydrocarbon-oxidizing bacteria].the activity of esterase was studied in bacteria oxidizing hydrocarbons and belonging to the genera rhodococcus, arthrobacter and pseudomonas. indophenyl acetate was used as a substrate of the reaction catalysed by the enzyme. exocellular esterases were not found. endocellular esterases differed in their activity and thermostability both among the genera and among species of one and the same genus.19863102911
phylogenetic analysis of the coryneform bacteria by 5s rrna sequences.nucleotide sequences of 5s rrnas from 11 coryneform bacteria were determined. these were the type strains of corynebacterium glutamicum, corynebacterium xerosis, brevibacterium linens, arthrobacter globiformis, cellulomonas biazotea, aureobacterium testaceum, curtobacterium citreum, pimelobacter simplex, and caseobacter polymorphus and representative strains of "corynebacterium aquaticum" and corynebacterium xerosis. a phylogenetic tree constructed from the sequences of these bacteria and publis ...19873106318
metabolism of endogenous trehalose by streptomyces griseus spores and by spores or cells of other actinomycetes.the disaccharide trehalose is accumulated as a storage product by spores of streptomyces griseus. nongerminating spores used their trehalose reserves slowly when incubated in buffer for several months. in contrast, spores rapidly depleted their trehalose pools during the first hours of germination. extracts of dormant spores contained a high specific activity of the enzyme trehalase. the level of trehalase remained relatively constant during germination or incubation in buffer. nongerminating sp ...19873117770
integration of bioconversions and downstream processing. some model studies. 19873124693
glycosaminoglycans in cortical autopsy samples from alzheimer brain.each of the known classes of mammalian glycosaminoglycans, with the exception of keratan sulphate, was found in cerebral cortex samples from patients with alzheimer-type dementia and age-matched controls. these molecules were quantitated, after electrophoresis and staining with alcian blue dye, by scanning densitometry. no significant differences were found between the mean levels of each of the above glycosaminoglycans in frontal cortex from patients with dementia compared with controls. an inc ...19883139840
cometabolism of polychlorinated biphenyls: enhanced transformation of aroclor 1254 by growing bacterial cells.acinetobacter sp. strain p6 and a soil isolate, arthrobacter sp. strain b1b, were tested for their ability to transform aroclor 1254 as washed resting cells and as growing cells with biphenyl as the substrate. growing cells were far superior to resting-cell suspensions in terms of total polychlorinated biphenyl (pcb) transformation, transformation of specific pcb congeners, and diversity of congeners that were attacked. growing cells of acinetobacter sp. strain p6 and arthrobacter sp. strain b1b ...19883140725
siderophore production by the pathogenic yeast, candida albicans.biochemical assays were used to determine that some strains of candida albicans were capable of simultaneous secretion of both the hydroxamate and phenolate-type siderophores when grown in a deferrated medium at 37 degrees c. all isolants of c. albicans released hydroxamate-type siderophores into the culture medium; whereas, approximately 40% of the strains simultaneously secreted phenolate-type siderophores. the presence of phenolate and hydroxamate-type siderophores in the culture medium was f ...19853161506
interaction of n-acetyl-4-epi-d-neuraminic acid with key enzymes of sialic acid spite of the axially orientated hydroxy group at c-4, the benzyl alpha-glycoside of n-acetyl-4-epi-d-neuraminic acid (4-epi-neuac) is a substrate for sialidases from vibrio cholerae, clostridium perfringens, and arthrobacter ureafaciens, although to an extent which differs depending on the enzyme. surprisingly, v. cholerae sialidase is by far the slowest acting enzyme; this is in contrast to its usual behavior. fowl plague virus sialidase and bovine testis sialidase also cleave this glycoside ...19883166979
structure of a ganglioside with cad blood group antigen activity.the cad antigen is a rare erythrocyte blood group antigen expressed on both sialoglycoprotein and ganglioside structures. it is related both serologically and biochemically to the sda blood group antigen expressed on over 90% of caucasian erythrocytes. we reported previously that cad erythrocytes contain a novel ganglioside that binds helix pomatia lectin and inhibits human anti-sda antibody. we have now purified the cad ganglioside and determined its structure. the ganglioside contained glc-gal ...19883167001
metabolic products of microorganisms. 249. tetracenomycins b3 and d3, key intermediates of the elloramycin and tetracenomycin c biosynthesis.tetracenomycins b3 and d3, besides tetracenomycin d (d1), were produced by a blocked mutant of the elloramycin producer streptomyces olivaceus tu 2353. the compounds were isolated as red powders, and their structures were elucidated by comparing their physicochemical data with those of the known tetracenomycins a2, b1, b2, d and e. tetracenomycin b3 (2), the main compound, and tetracenomycin d (3) were antibiotically inactive against gram-positive and gram-negative bacteria, whereas tetracenomyc ...19883170342
synthetic ferrichrome analogues with growth promotion activity for arthrobacter flavescens.two families of trihydroxamic acid analogues of ferrichrome were chemically synthesized and tested for biological activity with arthrobacter flavescens. compounds using a tertiary amine as anchor showed little activity. several compounds using tetrahedral carbon as anchor showed activity approaching or equalling that of the natural siderophore, ferrichrome. the biological activity is discussed in relation to physical and chemical properties of the analogues.19883196346
molecular cloning of the penicillin g acylase gene from arthrobacter viscosus.penicillin g acylase was purified from the cultured filtrate of arthrobacter viscosus 8895gu and was found to consist of two distinct subunits with apparent molecular weights of 24,000 (alpha) and 60,000 (beta). the partial n-terminal amino acid sequences of the alpha and beta subunits were determined with a protein gas phase sequencer, and a 29-base oligonucleotide corresponding to the partial amino acid sequence of the alpha subunit was synthesized. an escherichia coli transformant having the ...19883214149
oxidative side-chain and ring fission of pregnanes by arthrobacter simplex.metabolic processes involving side-chain and ring cleavage of progesterone, 17-hydroxyprogesterone, 11-deoxycortisol and 16-dehydropregnenolone by arthrobacter simplex were studied. the formation of the metabolites from progesterone indicates a pathway somewhat different from normal in the enzymic reaction sequence, and the 17-hydroxyprogesterone metabolites reveal a non-enzymic rearrangement step. the presence of a hydroxy group at c-21, as in 11-deoxycortisol, induces reduction of the c-20 car ...19883214423
[the structure of extracellular polysaccharide of arthrobacter globiformis].an extracellular polysaccharide from arthrobacter globiformis is composed of n-acetyl-d-glucosamine, n-acetyl-d-fucosamine, 2,3-diacetamido-2,3-dideoxy-d-mannuronic acid and o-acetyl groups in the ratio 1:1:2:1. on the basis of solvolysis with anhydrous hydrogen fluoride, which resulted in a tetrasaccharide fragment, and analysis by 1h and 13nmr spectroscopy, it was concluded that the polysaccharide has the following structure: (formula; see text).19883219122
three dehalogenases and physiological restraints in the biodegradation of haloalkanes by arthrobacter sp. strain ha1.arthrobacter sp. strain ha1 utilizes 18 c2-to-c8 1-haloalkanes for growth and synthesizes an inducible 1-bromoalkane debrominase of unknown physiological function (r. scholtz, t. leisinger, f. suter, and a.m. cook, j. bacteriol. 169:5016-5021, 1987) in addition to an inducible 1-chlorohexane halidohydrolase which dehalogenates some 50 substrates, including alpha, omega-dihaloalkanes. alpha, omega-dihaloalkanes were utilized by cultures of strain ha1 under certain conditions only. c9 and c8 homol ...19883223767
enzymatic dehalogenation of 4-chlorobenzoate by extracts from arthrobacter sp. su dsm extracts from arthrobacter sp. su dsm 20407 an enzyme was detectable, that converted 4-chlorobenzoate into 4-hydroxybenzoate. this conversion was also observed when no oxygen was present in the reaction mixture. boiling for 5 min destroyed the enzyme activity. 4-bromo- and 4-iodobenzoate were substrates for the enzyme too, but not 4-fluorobenzoate, 4-chlorophenylacetate and 4-chlorocinnamic acid. the enzyme showed optimum activity at 16 degrees c and at ph 7-7.5. the specific activity in the ...19883223988
degradation of 3-aminophenol by arthrobacter spec. ma3.the bacterial strain ma3 capable of utilizing 3-aminophenol as the sole source of carbon, energy and nitrogen for growth was isolated from an enrichment culture and identified as an arthrobacter species. utilization of 0.68 mg/ml 3-aminophenol by batch cultures of this organism was characterized by a specific growth rate (mu) of 0.18 h-1 and a yield coefficient (y) of 0.60. in chemostat cultures of strain ma3 we determined a critical dilution rate (dc) of 0.175 h-1 by continuous addition of mine ...19883236220
stereochemical studies of d-glucal hydration by alpha-glucosidases and exo-alpha-glucanases: indications of plastic and conserved phases in catalysis by glycosylases.alpha-glucosidases from aspergillus niger, pig serum, ungerminated rice, buckwheat, and sugar beet seeds (but not from brewers' yeast or honeybee) were found to catalyze the hydration of d-glucal. each reactive alpha-glucosidase, incubated with d-glucal in d2o, was shown to protonate (deuteriate) this prochiral substrate from above its re face, i.e., from a direction opposite that assumed for protonating alpha-d-glucosidic substrates. at the same time, d-glucal hydration catalyzed by three of th ...19883284583
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