TitleAbstractYear(sorted ascending)
biodegradation by an arthrobacter species of hydrocarbons partitioned into an organic arthrobacter strain mineralized naphthalene and n-hexadecane dissolved in 2,2,4,4,6,8,8-heptamethylnonane. the extent of mineralization increased with greater volumes of solvent. measurements under aseptic conditions of the partitioning of naphthalene into the aqueous phase from the solid phase or from heptamethylnonane showed that the rates were rapid and did not limit mineralization. the rate of mineralization of hexadecane was rapid, although partitioning of the compound into aqueous solut ...199116348485
competition for ammonium between nitrifying and heterotrophic bacteria in dual energy-limited chemostats.the absence of nitrification in soils rich in organic matter has often been reported. therefore, competition for limiting amounts of ammonium between the chemolithotrophic ammonium-oxidizing species nitrosomonas europaea and the heterotrophic species arthrobacter globiformis was studied in the presence of nitrobacter winogradskyi in continuous cultures at dilution rates of 0.004 and 0.01 h. ammonium limitation of a. globiformis was achieved by increasing the glucose concentration in the reservoi ...199116348588
ultrasound-enhanced bioprocess. ii: dehydrogenation of hydrocortisone by arthrobacter simplex.dehydrogenation of hydrocortisone by agitated suspensions of free and immobilized cells of arthrobacter simplex atcc 6946 was investigated under controlled ultrasonic irradiation at a frequency of 20 kh(z). the microbial conversion was optimized first with respect to mechanical agitation and subsequently with respect to an additionally superimposed sonication. the optimization of ultrasound intensity and its mode of application were established at a level which maintained the structural integrit ...199118597329
effects of solvent molecular toxicity and microenvironment composition on the delta(1) dehydrogenataon activity of arthrobacter simplex cells.solvent selection tests were carried out for the delta(1) dehydrogenation of 6-alpha-methylhydrocortisone-21-acetate by arthrobacter simplex cells in the presence of organic solvents. solubility limits were determined for substrate and product in dry and water-saturated solvents and solvent mixtures. molecular toxicity levels were estimated by measuring the dehydrogenation activity decay of freely suspended cells incubated in solvent-saturated aqueous media. chloroform and n-decan-1-ol were the ...199118597345
steroid bioconversion in a microemulsion system.the delta(1,2)-dehydrogenation of high concentrations of the steroid -methyl-reichstein's compound s-21-acetate (16mrsa) in a microemulsion system was studied using heat-dried and thawed arthrobacter simplex cells as biocatalyst. the microemulsion system consists of an organic phase [75-95% (v/v)] with steroid (1-60 g/l(tot)), an aqueous phase [5-25% (v/v)] containing the cells (5-30 g/l(tot)), and a neutral surfactant (5-20 g/l organic solvent). benzene derivatives, which solubilize 16mrsa up t ...199118600717
effect of adsorbents on degradation of toxic organic compounds by coimmobilized systems.the use of coimmobilized systems for treatment of toxic organic compounds has been proposed. the proposed approach combines the use of adsorbents and laboratory identified microorganisms immobilized in a protective permeable barrier to achieve a greater degree of control over the remediation process. this study was launched to understand the effect of adsorbents and changes in adsorption on the degradation of toxic compounds by coimmobilized systems. the specific case studied involved the degrad ...199218600991
activity and stability of an entrapped-cell system for the delta(1)-dehydrogenation of steroids in organic media.whole arthrobacter simplex cells entrapped in kappa-carra-geenan or in two types of polyurethane foam, or adsorbed on silanized celite, were tested for the delta(1)-dehydrogenation of hydrocortisone and its derivatives in organic media. catalytic activity and stability levels were evaluated for the immobilized cells in buffer with 2.5% (vol/vol) methanol, and in three buffer-saturated solvents (n-octan-1-ol, n-decan-1-ol, and chloroform). the addition of glutamate to the immobilization support s ...199218601223
effects of grazing by flagellates on competition for ammonium between nitrifying and heterotrophic bacteria in chemostats.the enhanced mineralization of organic nitrogen by bacteriophagous protozoa is thought to favor the nitrification process in soils, in which nitrifying bacteria have to compete with heterotrophic bacteria for the available ammonium. to obtain more insight into this process, the influence of grazing by the bacteriovorous flagellate adriamonas peritocrescens on the competition for limiting amounts of ammonium between the ammonium-oxidizing species nitrosomonas europaea and the heterotrophic specie ...199216348722
relationship between transport of bacteria and their clogging efficiency in sand an earlier article, we reported that, under conditions in which neither exopolymers nor bacterial mats were produced, arthrobacter sp. strain ak19 was an effective plugging agent in sand columns, whereas the bacterial strain sli had no significant effect on the permeability of the medium. a laboratory experiment with sand columns was carried out to elucidate the causes of this difference in behavior. measured values of the saturated hydraulic conductivity of the sand were explained in terms o ...199216348753
competition for ammonium between nitrifying and heterotrophic bacteria in continuously percolated soil columns.although the absence of nitrate formation in grassland soils rich in organic matter has often been reported, low numbers of nitrifying bacteria are still found in these soils. to obtain more insight into these observations, we studied the competition for limiting amounts of ammonium between the chemolithotrophic ammonium-oxidizing species nitrosomonas europaea and the heterotrophic species arthrobacter globiformis in the presence of nitrobacter winogradskyi with soil columns containing calcareou ...199216348787
scanning electron and light microscopic study of microbial succession on bethlehem st. nectaire nectaire cheese is a semisoft cheese of french origin that, along with brie and camembert cheeses, belongs to the class of surface mold-ripened cheese. the surface microorganisms that develop on the cheese rind during ripening impart a distinctive aroma and flavor to this class of cheese. we have documented the sequential appearance of microorganisms on the cheese rind and in the curd over a 60-day ripening period. scanning electron microscopy was used to visualize the development of surface ...199216348797
heteropolysaccharide formation by arthrobacter viscosus grown on xylose and xylose oligosaccharides.arthrobacter viscosus nrrl b-1973 produces its viscous extracellular polysaccharides (eps) when grown on media containing xylose or enzymatic xylan hydrolysates. crude eps formation from xylose averaged 12 g/liter when initial culture ph was adjusted to 8.0 and total nitrogen was limited to 0.03%. purified eps from pentose and hexose substrates were analyzed for their monosaccharide, acetyl, and uronic acid components, intrinsic viscosities, and average molecular masses. differences were apparen ...199216348800
taxonomic study of the genus brachybacterium: brachybacterium nesterenkovii sp. nov.a new species, brachybacterium nesterenkovii, is proposed for a group of coryneform bacteria that were isolated from milk products. these organisms have morphological, biochemical, and chemotaxonomic characteristics that are peculiar to the genus brachybacterium. in contrast to strains of the only previously described species of the genus, brachybacterium faecium, the representatives of the new species lack glycine in their peptidoglycan, although the peptidoglycan is of the same general type, a ...19921736971
structural study of cell wall mannan of a candida albicans (serotype a) strain.the structure of the mannan of candida albicans nih a-207 strain (serotype a) was investigated by adopting mild acetolysis followed by enzymolysis with an arthrobacter gjm-1 exo-alpha-mannosidase. the resultant oligosaccharides, from pentaose to octaose (where manp = d-mannopyranose), were identified as manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp, manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)- manp alpha (1----2)manp, manp beta (1- ...19921368047
action of levan fructotransferase of arthrobacter ureafaciens on a mixture of branched levanpentasaccharides. 19921368345
screening of whole-cell immobilization procedures for the delta 1-dehydrogenation of steroids in organic medium.different whole-cell immobilization methods and conditions were tested for the delta 1-dehydrogenation of 6-alpha-methyl-hydrocortisone-21-acetate with arthrobacter simplex cells, in n-decane-1-ol and chloroform. among the entrapment methods, polyurethane foams gave the best productivity of n-decane-1-ol, but could not be used in chloroform. partition and diffusional barriers appeared to be the factors limiting productivity in entrapped-cell systems. the coentrapment of enzyme-stabilizing (glyce ...19921368890
inhibition of development of kaposi's sarcoma-related lesions by a bacterial cell wall vitro and in vivo model systems for the study of human immunodeficiency virus (hiv)-associated kaposi's sarcoma (ks) were used to evaluate compounds for their potential as therapeutic agents. a sulfated polysaccharide-peptidoglycan compound (sp-pg) produced by bacteria controlled the in vitro growth of acquired immunodeficiency syndrome (aids)-associated, ks-derived spindle-shaped cells (aids-ks cells) at noncytotoxic concentrations. angiogenesis induced by aids-ks cells in the chicken chorio ...19921371891
whipple's disease, familial mediterranean fever, adult-onset still's disease, and enteropathic arthritis.whipple's disease is a rare multisystem disorder of infectious etiology. efforts to culture the responsible organism have been unsuccessful. nucleotide sequencing and amplification of bacterial 16s ribosomal dna revealed the organism to be most similar to bacteria of the rhodococcus, streptomyces, and arthrobacter genera. several clinical studies of the long-term use of colchicine for the treatment of familial mediterranean fever demonstrate its utility for symptom control and prevention of comp ...19921380277
crystal structure analysis, refinement and enzymatic reaction mechanism of n-carbamoylsarcosine amidohydrolase from arthrobacter sp. at 2.0 a resolution.n-carbamoylsarcosine amidohydrolase from arthrobacter sp., a tetramer of polypeptides with 264 amino acid residues each, has been crystallized and its structure solved and refined at 2.0 a resolution, to a crystallographic r-factor of 18.6%. the crystals employed in the analysis contain one tetramer of 116,000 m(r) in the asymmetric unit. the structure determination proceeded by multiple isomorphous replacement, followed by solvent-flattening and density averaging about the local diads within th ...19921381445
epimerization of reducing terminal groups of (1----2)-linked d-gluco- and d-manno-disaccharides in aqueous sodium hydroxide. 19921394294
structure of the d-mannan of the pathogenic yeast, candida stellatoidea atcc 20408 (type ii) strain, in comparison with that of c. stellatoidea atcc 36232 (type i) strain.acid treatment of the cell-wall d-mannas of candida stellatoidea strains atcc 36232 (type i, a3 strain) and atcc 20408 (type ii, a2 strain) gave (1----2)-linked beta-d-manno-oligosaccharides (dp 2-5), whereas treatment with alkali gave the (1----2)-linked alpha-d-mannobiose. conventional acetolysis of the acid- and alkali-treated d-mannan of the a3 strain gave oligosaccharides consisting of (1----2)- and (1----3)-linked alpha-d-mannopyranose residues, similar to those of candida albicans serotyp ...19921394307
purification and properties of an arthrobacter oxydans p52 carbamate hydrolase specific for the herbicide phenmedipham and nucleotide sequence of the corresponding gene.arthrobacter oxydans p52 isolated from soil samples was found to degrade the phenylcarbamate herbicides phenmedipham and desmedipham cometabolically by hydrolyzing their central carbamate linkages. the phenylcarbamate hydrolase (phenmedipham hydrolase) responsible for the degradative reaction was purified to homogeneity. the enzyme was shown to be a monomer with a molecular weight of 55,000. a 41-kb wild-type plasmid (php52) was identified in a. oxydans p52, but not in a derivative of this strai ...19921400211
microbial degradation of propoxur in turfgrass soil.this study was conducted to determine the degradation rates in turfgrass soil over a 12-month period after a single field application of propoxur and to isolate microorganisms from the soil capable of degrading the insecticide. soil samples were collected from a turfgrass experimental site near fort lauderdale, fl one week before the field application of propoxur, and over a 12-month period after the field application. mineralization rates in surface (0-15 cm depth) and subsurface (15-30 cm dept ...19921401729
cloning and nucleotide sequence of the csp1 gene encoding ps1, one of the two major secreted proteins of corynebacterium glutamicum: the deduced n-terminal region of ps1 is similar to the mycobacterium antigen 85 complex.two proteins, ps1 and ps2, were detected in the culture medium of corynebacterium glutamicum and are the major proteins secreted by this bacterium. no enzymatic activity was identified for either of the two proteins. immunologically cross-reacting proteins were found in a variety of c. glutamicum strains but not in the coryneform arthrobacter aureus. the gene encoding ps1, csp1, was cloned in lambda gt11 using polyclonal antibodies raised against ps1 to screen for producing clones. the csp1 gene ...19921406274
biosynthesis and distribution of n-carboxyalkyl amino acids (opines) in bacteria. 19921410788
[biotransformation of zearalenone].the conversion of zearalenone by some strains of microorganisms was investigated. when the selective strains of rhodotorula sp., arthrobacter sp., saccharomyces sp., and candida sp. were incubated by shaking or standing at 28 degrees c for 72 h with an alcoholic solution of zearalenone as the substrate at a concentration of 2-10 mg/ml ethanol (50-100 micrograms/ml medium), it was readily converted to give zearalenols, consisting either mainly of the alpha-isomer (e.g. 96% in case of rhodotorula ...19921413733
[microbiological production of 3-oxo-bisnorchola-1, 4-dien-22-oic acid from cholesterol by an arthrobacter 82].among nineteen strains of arthrobacter which showed to be able to decompose cholesterol in preliminary experiments, a strain of arthrobacter 82 was selected for microbiological production of 3-oxo-bisnorchola-1,4-dien-22-oic-acid (bnc) from cholesterol. the yield is over of 50% weight percent concentration of 0.25% in the presence of cobalt sulfate. the main intermediate in such a conversion process is cholestenone. lower glucose and higher corn steep liquor concentration were favorable for side ...19921413734
purification and characterization of an nad(+)-linked formaldehyde dehydrogenase from the facultative rump cycle methylotroph arthrobacter p1.when arthrobacter p1 is grown on choline, betaine, dimethylglycine or sarcosine, an nad(+)-dependent formaldehyde dehydrogenase is induced. this formaldehyde dehydrogenase has been purified using ammonium sulphate fractionation, anion exchange- and hydrophobic interaction chromatography. the molecular mass of the native enzyme was 115 kda +/- 10 kda. gel electrophoresis in the presence of sodium dodecyl sulphate indicated that the molecular mass of the subunit was 56 kda +/- 3 kda, which is cons ...19921416916
immunological demonstration of a unique 3,4-dihydroxyphenylacetate 2,3-dioxygenase in soil arthrobacter strains.many bacteria biosynthesize 3,4-dihydroxyphenylacetate 2,3-dioxygenases for growth on aromatic acids, but gram-negative organisms have been most extensively studied. a gram-positive strain containing 2,3-dioxygenase activity was identified as arthrobacter strain mn-1. the 2,3-dioxygenase from strain mn-1 was purified to homogeneity by fast protein liquid chromatography with a mono q anion-exchange column. rabbit polyclonal antidioxygenase antibodies were prepared. ouchterlony double-diffusion an ...19921444392
isolation and characterization of a fluorene-degrading bacterium: identification of ring oxidation and ring fission arthrobacter sp. strain, f101, able to use fluorene as the sole source of carbon and energy, was isolated from sludge from an oil refinery wastewater treatment plant. during growth in the presence of fluorene, four major metabolites were detected and isolated by thin-layer chromatography and high-performance liquid chromatography. 9-fluorenol, 9h-fluoren-9-one, and 3,4-dihydrocoumarin were identified by uv spectra, mass spectrometry, and 300-mhz proton nuclear magnetic resonance. the fourth m ...19921444405
[plasmids for biodegradation of 2,6-dimethylpyridine, 2,4-dimethylpyridine, and pyridine in strains of arthrobacter].arthrobacter crysallopoietes strain km-4 degrading 2,6-dimethylpyridine and strain km-4a degrading both 2,6-dimethylpyridine and pyridine, arthrobacter sp. km-4b degrading 2,4-dimethylpyridine were isolated from soil. arthrobacter crystallopoietes km-4 and arthrobacter sp. km-4b contain 100 md plasmids pbs320 and pbs323. arthrobacter crystallopietes km-4a harbours a 100 md and 80 md plasmids. plasmid curing and conjugation transfer results confirm that these plasmids are involved in degradation ...19921454076
structure of the n- and o-glycans of the a-chain of human plasma alpha 2hs-glycoprotein as deduced from the chemical compositions of the derivatives prepared by stepwise degradation with exoglycosidases.the structure of the glycans of the a-chain of human plasma alpha 2hs-glycoprotein was established from the chemical compositions of its derivatives prepared by sequential enzymatic degradation of the carbohydrate moiety, from the determination of the kind and amount of the monosaccharides liberated after each step of the enzymatic digestion, and from the distinct specificity of the highly purified exoglycosidases. the exoglycosidases were three sialidases (vibrio cholerae, fowl plague virus, an ...19921457416
anomeric specificity of d-xylose isomerase.crystal structures of complexes of d-xylose isomerase with deoxysugars have been determined. deoxynojirimycin is a structural analogue of alpha-pyranose and mimics the binding of these aldose substrates. the structure of this complex supports the hypothesis that an imidazole group catalyzes ring opening of the pyranose. the steric restrictions in the active site of the enzyme prevent a beta-pyranose from binding in the same way. for the reverse reaction with ketoses, the anomeric specificity is ...19921457418
mineralization of 2-chloro- and 2,5-dichlorobiphenyl by pseudomonas sp. strain ucr2.pseudomonas sp. strain ucr2 was isolated from a multi-chemostat mating experiment between a chlorobenzoate-degrader, pseudomonas aeruginosa strain jb2, and a chlorobiphenyl-degrader, arthrobacter sp. strain b1barc. strain ucr2 differed from either of the parental organisms in that it grew on both 2-chloro- and 2,5-dichlorobiphenyl with concomitant release of chloride. phenotypic typing by the biolog system indicated that strain ucr2 shared greater similarity with strain jb2 (88%) than strain b1b ...19921459405
siderophores and related outer membrane proteins produced by pseudomonads isolated from eels and freshwater.a total of 46 environmental pseudomonads, together with six type strains, were examined for their siderophore-producing activity. all strains were able to grow under iron-limiting conditions, gave orange halos in the cas agar assay, and produced hydroxamates, and some of them also produced phenolate-type compounds. bioassays showed that all strains, except pseudomonas aeruginosa, promoted growth of mutant strain arthrobacter flavescens jg-9, deficient in hydroxamate production, and some of them ...19921459416
cloning and sequence analysis of genes for dehalogenation of 4-chlorobenzoate from arthrobacter sp. strain su.strains of arthrobacter catalyze a hydrolytic dehalogenation of 4-chlorobenzoate (4-cba) to p-hydroxybenzoate. the reaction requires atp and coenzyme a (coa), indicating activation of the substrate via a thioester, like that reported for pseudomonas sp. strain cbs3 (j. d. scholten, k.-h. chang, p. c. babbit, h. charest, m. sylvestre, and d. dunaway-mariano, science 253:182-185, 1991). the dehalogenase genes of arthrobacter sp. strain su were cloned and expressed in escherichia coli. analyses of ...19921476446
stability of arthrobacter d-xylose isomerase to denaturants and heat.there was no inactivation of mg(2+)-containing arthrobacter d-xylose isomerase up to 1 h in 0-8 m-urea at 22 degrees c, but over this range there was rapid reversible dissociation into fully active dimers with a midpoint around 4 m-urea, as shown by gradient urea gels with an activity stain, and by ion-exchange chromatography and gel filtration in urea buffers. these dimers must have the a-b* conformation, since the tetramer could dissociate into a-a*, a-b or a-b* dimer conformations, but only r ...19921497626
application of a microbial sensor for determination of short-chain fatty acids in raw milk samples.a microbial sensor system, based on the use of immobilized arthrobacter nicotiana and an oxygen electrode, was applied to determine free short-chain fatty acids in raw milk samples and the result was compared with gas chromatography (gc) and a titrimetric method. the sensor response was linearly related to the concentration of short-chain fatty acids obtained by gc (n = 10, r = 0.92) and to the total concentration of free fatty acids obtained by titrimetric measurement (n = 10, r = 0.78). this r ...19921502853
chemotaxonomic differentiation of coryneform bacteria isolated from biofilters.coryneform bacteria that were isolated from biofilters which are used for waste gas treatment of animal-rendering plant emissions were differentiated and partially identified by using chemotaxonomic methods. on the basis of the results of a numerical analysis of whole-cell fatty acid profiles, 79 isolates were divided into two major groups; the members of the first group contained saturated and monounsaturated fatty acids, whereas the members of the second group were characterized by iso- and an ...19921503976
the structural genes encoding co dehydrogenase subunits (cox l, m and s) in pseudomonas carboxydovorans om5 reside on plasmid phcg3 and are, with the exception of streptomyces thermoautotrophicus, conserved in carboxydotrophic bacteria.employing deoxyoligonucleotide probes and southern hybridizations, we have examined in carboxydotrophic bacteria the localization on the genome of genes encoding the large, medium and small subunits of co dehydrogenase (coxl, m and s, respectively). in pseudomonas carboxydovorans om5 coxl, m and s were identified on the plasmid phcg3; they were absent on the chromosome. this was evident from positive hybridizations with plasmid dna of the wild-type strain om5 and the absence of hybridizations wi ...19921510563
biosynthesis of a nonphysiological sialic acid in different rat organs, using n-propanoyl-d-hexosamines as this study it could be shown that in rat the normally occurring n-acetyl neuraminic acid can be modified in its n-acyl moiety by in vivo administration of the chemically synthesized n-propanoyl precursors, n-propanoyl-d-glucosamine or n-propanoyl-d-mannosamine. it could be shown that each of these nonphysiological amino sugar analogues was incorporated into both membrane and serum glycoproteins. after treatment of rats with radiolabeled n-[acyl-1-14c]d-mannosamine, radioactivity could be remo ...19921512235
metabolic blocks in the degradation of beta-sitosterol by a plasmid-cured strain of arthrobacter oxydans.plasmid-harbouring, sterol-decomposing organism arthrobacter oxydans 317 was treated with sodium dodecylsulphate to obtain a plasmid-cured strain a. oxydans 317 a1 incapable of utilizing 4-androstene-3,17-dione (ad). the strain 317 a1 was unable to degrade beta-sitosterol side chain completely to form ad but could carry out partial degradation as shown by the accumulation of 3-oxochol-4-en-24-oic acid as a major metabolite and 27-norcholest-4-en-3,24-dione as a minor metabolite. the strain could ...19921512707
[effect of normal and specific immune sera on neuraminidase activity].we have got evidence that there is no antigenic relationship reflecting the structural similarity between neuraminidases synthesized by noncholera vibrios and arthrobacter nicotianae. the cross-reactions between the enzymes and heterological antisera were not observed. antibodies against the a. nicotianae neuraminidase inhibited the activity of the enzyme for a glycomacropeptide of milk whey and for components of the blood serum, and had no effect no the neuraminidase from noncholera vibrios. an ...19921528820
indole-3-acetic acid (iaa) production by arthrobacter species isolated from azolla.arthrobacter species, isolated from the leaf cavities and the microsporocarps of the aquatic fern species azolla pinnata and azolla filiculoides, produced indole-3-acetic acid (iaa) in culture when the precursor tryptophan was added to the medium. no iaa production was detected in the absence of tryptophan. maximum iaa formation was obtained in the first 2 d of incubation. part of the tryptophan was transformed to n alpha-acetyl-l-tryptophan.19921564446
mechanism of d-fructose isomerization by arthrobacter d-xylose isomerase.the mechanism of d-fructose isomerization by arthrobacter d-xylose isomerase suggested from x-ray-crystallographic studies was tested by detailed kinetic analysis of the enzyme with various metal ions at different ph values and temperatures. at d-fructose concentrations used in commercial processes mg2+ is the best activator with an apparent dissociation constant of 63 microm; co2+ and mn2+ bind more strongly (apparent kd 20 microm and 10 microm respectively) but give less activity (45% and 8% r ...19921567370
levels of trehalose and glycogen in arthrobacter globiformis under conditions of nutrient starvation and osmotic stress.cells of arthrobacter globiformis grown in carbohydrate-rich media were found to contain large quantities of low-mr carbohydrates (800 micrograms/mg protein) and only small amounts of amino acids, in addition to high amounts of glycogen (2 mg/mg protein). at increasing osmotic values of the medium, low-mr carbohydrate levels increased to 1300 micrograms/mg protein. low-mr pools were extracted from the cells with hot 75% ethanol, and subjected to thin layer, gel and gas-liquid chromatography. the ...19921575469
reclassification of two strains of arthrobacter oxydans and proposal of arthrobacter nicotinovorans sp. nov.arthrobacter oxydans dsm 419 and dsm 420 have chemical and microbiological properties that are consistent with assignment to the genus arthrobacter. both organisms have the lysine-alanine-threonine-alanine peptidoglycan type. dna-dna pairing studies indicated that a. oxydans dsm 419 should be reclassified as arthrobacter ureafaciens and that a. oxydans dsm 420t forms the nucleus of a distinct genomic species. we propose that a. oxydans dsm 420 should be reclassified as arthrobacter nicotinovoran ...19921581183
bacteria that degrade p-chlorophenol isolated from a continuous culture system.two gram-positive coryneform bacteria that degraded p-chlorophenol isolated from a continuous culture system are characterized. isolate b (probably and arthrobacter sp.) completely removed the p-chlorophenol from a medium with a concomitant increase in cell density within 16 h. isolate f similarly removed the p-chlorophenol within 28 h but without an increase in cell density. isolates b and f also removed the p-chlorophenol from a medium with p-chlorophenol as the sole carbon source within 32 an ...19921581863
apoi, a unique restriction endonuclease from arthrobacter protophormiae which recognizes 5' raatty 3'. 19921614876
molecular mechanics simulations of a conformational rearrangement of d-xylose in the active site of d-xylose isomerase.a proposed reaction mechanism for the enzyme d-xylose isomerase involves the ring opening of the cyclic substrate with a subsequent conformational rearrangement to an extended open-chain form. restrained energy minimization was used to simulate the rearrangement. in the ring-opening step, the substrate energy function was gradually altered from a cyclic to an open-chain form, with energy minimization after each change. the protein/sugar contact energy did not increase significantly during the pr ...19921620692
hemicellulose bioconversion to polyanionic heteropolysaccharides.anionic polysaccharides, traditionally obtained from plant or algal sources, have a variety of commercial uses. such gums from microorganisms have received increased recent interest. we have initiated a program to investigate the bioconversion of pentosans to rheologically useful anionic extracellular polysaccharides (aeps). a number of earlier-described species, including cryptococcus laurentii, klebsiella pneumoniae, arthrobacter viscosus, and pseudomonas atcc 31260, appear to have potential i ...19921622201
effect of bacterial extracellular polymers on the saturated hydraulic conductivity of sand columns.columns were packed with clean quartz sand, sterilized, and inoculated with different strains of bacteria, which multiplied within the sand at the expense of a continuous supply of fresh nutrient medium. the saturated hydraulic conductivity (hcsat) of the sand was monitored over time. among the four bacterial strains tested, one formed a capsule, one produced slime layers, and two did not produce any detectable exopolymers. the last two strains were nonmucoid variants of the first two. only one ...19921622240
interaction of the regulatory protein nicr1 with the promoter region of the pao1-encoded 6-hydroxy-d-nicotine oxidase gene of arthrobacter oxidans.the d,l-nicotine catabolism of the gram-positive soil bacterium arthrobacter oxidans is linked to the presence within the cells of the 160 kb catabolic plasmid pao1. pao1-cured cells lost the catabolic enzymes and reintroduction of pao1 by electroporation into cured cells reestablished the nic+ phenotype. dna band shift assays with extracts from cured and pao1+ cells suggested that pao1 encodes the regulatory protein nicr1. footprint analysis revealed that two homologous palindromes (ir1 and ir2 ...19921630318
myceloid cell formation in arthrobacter globiformis during osmotic stress.arthrobacter globiformis was grown in a semi-defined liquid medium containing added solutes to determine the effects of osmotic stress on its reproduction and cell morphology. there was a progressive reduction in the specific growth rate during exponential phase as the concentration of nacl was increased, although the final yields of the cultures during stationary phase were not affected. clusters of branching myceloid cells rather than the typical bacillary forms predominated during exponential ...19921644706
multi-recognition capability of e-selectin in a dynamic flow system, as evidenced by differential effects of sialidases and anti-carbohydrate antibodies on selectin-mediated cell adhesion at low vs. high wall shear stress: a preliminary note.e-selectin has a "multi-recognition" capability in terms of epitope binding specificity, depending on adhesion conditions (static vs. low- or high-shear stress dynamic systems). specifically, (i) adhesion based on expression of alpha 2-->3 sialylated le(x) (sle(x)) is prominent under static or low shear stress dynamic conditions; (ii) adhesion under high shear stress dynamic conditions does not depend on the known sle(x) species, but rather on lex with an adjacent unidentified sialosyl substitut ...19921282810
[cloning and expression of the arthrobacter globiformis fcb genes in bacillus subtilis].the fcb genes of arthrobacter globiformis kzt1 coding for the dehalogenase (4-chlorobenzoate-4-hydroxylase) activity have been cloned. the characteristics of fcb genes expression have been studied. the recombinant strains of bacillus subtilis 6jm15 (pcbs 311) and 6jm15 (pcbs1) have shown the decreased level of substrate dehalogenation as compared with the one in the parent strain kzt1 and the recombinant strains of escherichia coli and pseudomonas putida.19921301499
effects of the membrane action of tetralin on the functional and structural properties of artificial and bacterial membranes.tetralin is toxic to bacterial cells at concentrations below 100 mumol/liter. to assess the inhibitory action of tetralin on bacterial membranes, a membrane model system, consisting of proteoliposomes in which beef heart cytochrome c oxidase was reconstituted as the proton motive force-generating mechanism, and several gram-positive and gram-negative bacteria were studied. because of its hydrophobicity, tetralin partitioned into lipid membranes preferentially (lipid/buffer partition coefficient ...19921314806
acsi, a new restriction endonuclease from arthrobacter citreus 310 recognizing 5'-pu decreases aattpy-3'. 19921322532
cloning, sequence analysis, and expression of the flavobacterium pentachlorophenol-4-monooxygenase gene in escherichia coli.the pcpb gene of flavobacterium sp. strain atcc 39723 was cloned by using a degenerate primer designed from the n-terminal sequence of the purified enzyme. the nucleotide sequence of pcpb was determined and found to encode an open reading frame of 1,614 nucleotides, yielding a predicted translation product of 538 amino acids, in agreement with the estimated size of the purified protein analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the transcriptional start of pcpb was fo ...19937678243
determination of the sialic acid linkage specificity of sialidases using lectins in a solid phase assay.a procedure for the determination of activity and linkage specificity of sialidases is described. the sialoglycoprotein fetuin is coated onto a microtiter plate and incubated with sialidases from different sources. enzymatic activities and linkage specificities are then determined by a sandwich method which measured the binding of different lectins to fetuin. the lectins used were peanut agglutinin (pna) from arachis hypogaea, which binds specifically the galactose beta-1-3-n-acetylgalactosamine ...19937686353
growth of mycorrhizal fungi in dixenic cultures with bacteria in media of different composition.studies were carried out on the effect of bacteria: arthrobacter globiformis, bacillus subtilis and pseudomonas fluorescens on biomass production by three important ectomycorrhizal fungi: laccaria laccata, hebeloma crustuliniforme and rhizopogon vinicolor in media of different composition. it was shown that bacteria stimulated, inhibited or did not affect significantly the biomass production by mycorrhizal fungi. 3-factor anova have shown that although effect of bacteria was statistically signif ...19937504874
production of cis,cis-muconic acid from benzoic acid. 19937763344
overproduction of riboflavin by an arthrobacter sp. mutant resistant to 5-fluorouracil.antagonistic action between 5-fluorouracil (5-fu) and riboflavin (rf) was investigated. the growth of arthrobacter sp. was inhibited by 5-fu at 5 x 10(-5) m, and the inhibition was reversed by rf at 5 x 10(-5) m. 5-fu-resistant mutants of arthrobacter sp. were isolated and excreted rf in relatively high yields, but the wild-type strain excreted no rf. one of the mutants, strain no. 28-35, produced 223.2 micrograms ml-1 of rf in culture medium at 4 days.19937764107
arthrobacter d-xylose isomerase: chemical modification of carboxy groups and protein engineering of ph try to lower the ph optimum, the carboxy groups of arthrobacter d-xylose isomerase were coupled to glycinamide using a water-soluble carbodi-imide. in conditions that substituted all of the 59 carboxy groups in the denatured monomer, a maximum of 30 groups/monomer reacted in the native enzyme, whether in presence or absence of ligands, and the enzyme remained fully active and tetrameric throughout the coupling reaction. purification by f.p.l.c. ion-exchange chromatography gave broad symmetric ...19937904154
photoaffinity labeling of acyl-coa oxidase with 12-azidooleoyl-coa and 12-[(4-azidosalicyl)amino]dodecanoyl-coa.synthesis of 32p-labeled coa of high specific activity was achieved using partially purified dephospho-coa kinase (ec from pig liver with [gamma-32p]atp as donor and dephospho-coa as acceptor. a photoaffinity dodecanoic acid analog, 12-[(4-azidosalicyl)amino]dodecanoic acid was synthesized, as were its coa derivative (asd-coa) and the coa derivative of 12-azidooleic acid. the coa derivatives were synthesized from azido fatty acid analogs by acyl-coa synthetase. the synthesized photolab ...19938241127
degradation and induction specificity in actinomycetes that degrade p-nitrophenol.we have isolated two soil bacteria (identified as arthrobacter aurescens tw17 and nocardia sp. strain tw2) capable of degrading p-nitrophenol (pnp) and numerous other phenolic compounds. a. aurescens tw17 contains a large plasmid which correlated with the pnp degradation phenotype. degradation of pnp by a. aurescens tw17 was induced by preexposure to pnp, 4-nitrocatechol, 3-methyl-4-nitrophenol, or m-nitrophenol, whereas pnp degradation by nocardia sp. strain tw2 was induced by pnp, 4-nitrocatec ...19938250573
structural characterization of the n-linked carbohydrate chains from mouse zona pellucida glycoproteins zp2 and zp3.n-linked oligosaccharides of mouse zona pellucida glycoproteins zp2 and zp3 were prepared as pyridylaminated derivatives. anion-exchange hplc revealed that 95% or more of them are acidic. about 80% of these acidic chains were neutralized by digestion with arthrobacter ureafaciens sialidase and a small amount of sulfate was found in the residual acidic chains. the neutralized fractions (sn fractions) from zp2 and zp3 were similarly fractionated by size-fractionation hplc into many peaks having di ...19938251520
transformation of cholic acid by arthrobacter simplex.fermentation of cholic acid with arthrobacter simplex (iicb 227) under aerobic conditions yielded 3,12-dioxo-23,24-dinorchola-4,6-dienoic acid, 7 alpha-hydroxy-3,12-dioxo-23,24-dinorchol-4-enoic acid, 3 alpha, 7 alpha-dihydroxy-12-oxo-5 beta-cholan-24-oic acid, 3 alpha, 7 alpha-dihydroxy-12-oxo-5 beta-23,24-dinorcholan-22-oic acid, 7 alpha, 12 alpha-dihydroxy-3-oxo-5 beta-cholan-24-oic acid, 7 alpha-12 alpha-dihydroxy-3-oxo-4-cholenoic acid, 7 alpha, 12 alpha-dihydroxy-3-oxo-23,24-dinorchol-4-en ...19938256259
vermiculin derivatives. part 1: synthesis of vermiculin derivatives.hydrogenation of the macrodiolide antibiotic vermiculin (1) over adams catalyst afforded [8s, 16s]-8,16-bis(2'-oxopropyl)-1,9- dioxyacyclohexadeca-2,5,10,13-tetrone (2), [8s, 16s]-8,16-bis(2'-oxopropyl)-13-hydroxy-1,9-dioxacyclohexadeca- 2,5,10-trione (3), [8s,16s]-8,16-bis(2' oxopropyl)-1,9- dioxacyclohexadeca-2,5,10-trione (4) together with [7s]-4,9-dioxo-7-(4',9'-dioxodecanoyloxy)decanoic acid (5). hydrogenation of diolide 1 over pd/c gave tetrahydrovermiculin (2) only. the prepared compounds ...19938265708
[effect of ozone on airborne microorganisms].the microbicidal effect of ozone in air was tested at concentrations between 50 and 600 micrograms/m3 against the species: staphylococcus epidermidis, micrococcus luteus, arthrobacter citreus, bacillus subtilis (veg.), escherichia coli, salmonella typhimurium, serratia marcescens, pseudomonas fluorescens and candida albicans. the microorganisms were exposed on membrane filters at 60-75% relative humidity and 21.5-22.5 degrees c. after exposure times between 1 min and 60 min, the filters were inc ...19938267833
molecular properties of aminopeptidase ey as a zinc-metalloenzyme.1. aminopeptidase ey from hen's egg yolk contains 1.0 g atom of zinc/mol of a subunit having molecular weight of 150 kda. the inactive, zn(2+)-free apoenzyme was reactivated by co2+, mn2+, ca2+, cd2+, cu2+ and ni2+ in addition to zn2+, whereas mg2+ and fe2+ were ineffective. 2. the enzymatical properties of reconstituted enzymes, except for zn(2+)-reconstituted enzyme, differed from native enzyme. the values for the activation energy were calculated by aminopeptidase ey and co(2+)-reconstituted ...19938288037
three different 2,3-dihydroxybiphenyl-1,2-dioxygenase genes in the gram-positive polychlorobiphenyl-degrading bacterium rhodococcus globerulus p6.rhodococcus globerulus p6 (previously designated acinetobacter sp. strain p6, arthrobacter sp. strain m5, and corynebacterium sp. strain mb1) is able to degrade a wide range of polychlorinated biphenyl (pcb) congeners. the genetic and biochemical analyses of the pcb catabolic pathway reported here have revealed the existence of a pcb gene cluster--bphbc1d--and two further bphc genes--bphc2 and bphc3--that encode three narrow-substrate-specificity enzymes (2,3-dihydroxybiphenyl dioxygenases) that ...19938335622
comparison of the activity of two chondroitin ac lyases on dermatan sulfate. 19938348558
inhibition of sialidases from viral, bacterial and mammalian sources by analogues of 2-deoxy-2,3-didehydro-n-acetylneuraminic acid modified at the c-4 position.the inhibition of sialidase activity from influenza viruses a and b, parainfluenza 2 virus, vibrio cholerae, arthrobacter ureafaciens, clostridium perfringens, and sheep liver by a range of 2-deoxy-2,3-didehydro-n-acetylneuraminic acid analogues modified at the c-4 position has been studied. all substitutions tested resulted in a decrease in the degree of inhibition of the bacterial and mammalian sialidases. for sialidases from influenza viruses a and b, on the other hand, most of the substituti ...19938358225
cloning, sequencing, expression, and regulation of the structural gene for the copper/topa quinone-containing methylamine oxidase from arthrobacter strain p1, a gram-positive facultative methylotroph.deoxyoligonucleotides corresponding to amino acid sequences of methylamine oxidase and polyclonal anti-methylamine oxidase antibodies were used to probe arthrobacter strain p1 plasmid and chromosomal dna libraries. two open reading frames, maoxi and maoxii, which are greater than 99% homologous, were cloned from the chromosomal library. the deduced amino acid sequences of the coding regions are identical except for two residues near the c termini. on the other hand, the 5'- and 3'-flanking regio ...19938366046
microbial degradation of chlorinated acetophenones.a defined mixed culture, consisting of an arthrobacter sp. and a micrococcus sp. and able to grow with 4-chloroacetophenone as a sole source of carbon and energy, was isolated. 4-chlorophenyl acetate, 4-chlorophenol, and 4-chlorocatechol were identified as metabolites through comparison of retention times and uv spectra with those of standard substances. the proposed pathway was further confirmed by investigation of enzymes. the roles of the two collaborating strains were studied by growth exper ...19938368855
expression and secretion of an arthrobacter dextranase in the oral bacterium streptococcus gordonii.we have constructed a plasmid to express and secrete dextranase in the oral bacterium streptococcus gordonii. the dextranase gene from arthrobacter sp. strain cb-8 was linked to a promoter and a dna sequence encoding the signal peptide of streptococcus downei glucosyltransferase i (gtfi) followed by the escherichia coli rrnbt1t2 terminator and inserted in the shuttle vector pva838. s. gordonii transformed with this plasmid (pmnk-4) expressed and secreted mature arthrobacter dextranase. the trans ...19938406828
a new lipopeptide biosurfactant produced by arthrobacter sp. strain mis38.a biosurfactant termed arthrofactin produced by arthrobacter species strain mis38 was purified and chemically characterized as 3-hydroxydecanoyl-d-leucyl-d-asparagyl-d-threonyl-d- leucyl-d-leucyl-d-seryl-l-leucyl-d-seryl-l-isoleucyl-l-isoleucyl-l-as paragyl lactone. surface activity of arthrofactin was examined, with surfactin as a control. critical micelle concentration values of arthrofactin and surfactin were around 1.0 x 10(-5) m and 7.0 x 10(-5) m at 25 degrees c, respectively. arthrofactin ...19938407822
cloning and characterization of a gene coding for the catechol 1,2-dioxygenase of arthrobacter sp. ma3.the cata gene, coding for the catechol 1,2-dioxygenase (c12o) of the bacterial strain arthrobacter sp. ma3, was cloned and expressed in escherichia coli. one plasmid containing a 6.1-kb ecori insert was selected by its ability to degrade catechol and to accumulate cis-cis-muconate. the dna insert of this plasmid was mapped with restriction enzymes. the cata gene was subcloned on a 1.3-kb psti-ecori fragment by deleting the adjacent restriction fragments. the nucleotide sequence of cata was deter ...19938423008
arthrobacter d-xylose isomerase: partial proteolysis with thermolysin.the pattern and kinetics of partial proteolysis of arthrobacter d-xylose isomerase tetramer was studied in order to determine the flexibility of surface loops that may control its stability. it was completely resistant to trypsin, chymotrypsin and elastase at 37 degrees c, but thermolysin cleaved specifically and quantitatively at thr-347-leu-348 between helices 10 and 11 to remove 47 residues from the c-terminus of each 43.3 kda subunit. at high temperatures, helices 9 and 10 were removed from ...19938424759
characterization of the methylenediphosphonate transport system in arthrobacter sp. glp-1 using the novel tritium-labelled derivative.the novel tritium-labelled derivative of methylenediphosphonate (mdp) was used in uptake studies of arthrobacter sp. glp-1 capable of utilizing a wide range of organophosphonates as its sole source of phosphorus. the mdp uptake was greatly stimulated upon phosphate deprivation. the uptake obeys michaelis-menten kinetics with respective km and vmax values of 33 microm and 0.3 fr.wt. glyphosate and pyrophosphate were competitive inhibitors of mdp uptake. the effect of orthophosphat ...19938428621
inositol-containing lipoglycans in prokaryotes. 19938449324
cloning and expression of the polychlorinated biphenyl-degradation gene cluster from arthrobacter m5 and comparison to analogous genes from gram-negative bacteria.arthrobacter m5 was characterized genetically to determine if the catabolic pathway (controlled by the bph genes), responsible for polychlorinated biphenyl (pcb) biodegradation in this gram-positive strain, was similar to the pathways characterized from various gram-negative bacteria. arthrobacter m5 was originally isolated as a contaminant from a culture of the pcb degrader, acinetobacter sp. strain p6. a bph-specific oligodeoxyribonucleotide (oligo) gene probe (bphc2) was designed by aligning ...19938449411
the m.alui dna-(cytosine c5)-methyltransferase has an unusually large, partially dispensable, variable region.the dna methyltransferase of the alui restriction-modification system, from arthrobacter luteus, converts cytosine to 5-methylcytosine in the sequence agct. the gene for this methyltransferase, aluim, was cloned into escherichia coli and sequenced. a 525-codon open reading frame was found, consistent with deletion evidence, and the deduced amino acid sequence revealed all ten conserved regions common to 5-methylcytosine methyltransferases. the aluim sequence predicts a protein of m(r) 59.0k, in ...19938451189
microbial metabolism of quinoline and related compounds. xvi. quinaldine oxidoreductase from arthrobacter spec. rü 61a: a molybdenum-containing enzyme catalysing the hydroxylation at c-4 of the heterocycle.quinaldine oxidoreductase from arthrobacter spec. rü 61a converts quinaldine to 1h-4-oxoquinaldine. the enzyme was purified 70-fold to apparent homogeneity in a 5-step procedure with a recovery of 4%. the molecular mass of the native enzyme was calculated to be 340,000 da by gel filtration. sds-polyacrylamide gel electrophoresis of the enzyme revealed 3 protein bands corresponding to 82,000 da, 35,000 da and 22,000 da. the enzyme contained 1.6 atoms of molybdenum, 8 atoms of iron, 8 atoms of aci ...19938471177
[arthrobacter proteinase and its effect on fibrin thrombi].arthrobacteria are producers of proteolytic enzymes. optimal cultivation conditions were determined for arthrobacter luteus and the mineral composition of the culture medium providing active synthesis of proteinase was optimized. the proteinase was isolated from the culture liquid of arthrobacter luteus using preparative ion-exchange chromatography on a carboxyl cation exchange resin kmt. the enzyme was homogeneous according to gel chromatography on sephadex g-200 and had a molecular weight of 2 ...19938475025
microbial production of d-malate from produce d-malate from maleate by a microbial reaction, we screened a number of maleate-utilizing microorganisms for enzyme activity by an intact cell system. the strain which showed the best productivity among the 440 strains tested was identified taxonomically as arthrobacter sp. strain mci2612. the optical purity of the malate produced by this strain was 100% d type. the culture and reaction conditions for the production were studied for this strain. addition of amino acids such as l-prolin ...19938476285
morphological, physiological and enzymatic characteristics of cephalosporin acylase-producing arthrobacter strain 45-8a.a bacterial strain producing cephalosporin acylases was isolated from soil. the morphological and physiological properties of this strain suggest that it belongs to the genus arthrobacter, and the isolate was therefore designated arthrobacter strain 45-8a. substrate specificity of the enzyme was examined. the enzyme can convert both cephalosporin acid to 7-aminocephalosporanic acid. an interesting feature of the acylases is their temperature-dependent regulation. activity of acylases was detecte ...19938484708
arthrobacter d-xylose isomerase: protein-engineered subunit interfaces.mutants of arthrobacter d-xylose isomerase were constructed in which one or two disulphide bridges or additional salt bridges were introduced at the a-a* subunit interfaces. these showed no change in enzyme activity or stability compared with the wild-type enzyme. however, a tyr253 mutant in which a disulphide bridge was introduced at the a-b* subunit interface showed reduced thermostability that was identical in both oxidized and reduced forms, and also reduced stability in urea. x-ray-crystall ...19938484737
degradation of a sodium acrylate oligomer by an arthrobacter sp.arthrobacter sp. strain no-18 was first isolated from soil as a bacterium which could degrade the sodium acrylate oligomer and utilize it as the sole source of carbon. when 0.2% (wt/wt) oligomer was added to the culture medium, the acrylate oligomer was found to be degraded by 70 to 80% in 2 weeks, using gel permeation chromatography. to determine the maximum molecular weight for biodegradation, the degradation test was done with the hexamer, heptamer, and octamer, which were separated from the ...19938517751
molecular rearrangement of longifolene by arthrobacter ilicis t(2).arthrobacter ilicis t(2) brings about a unique type of cometabolic structural rearrangement of longifolene, a sesquiterpene, resulting in the formation of an acid. infrared, nuclear magnetic resonance, mass spectrometry, and decoupling studies indicate that the acid product has a sativenelike structure, which is confirmed by conversion of the acid to its methyl ester and hydrocarbon.199316348946
effects of grazing by flagellates on competition for ammonium between nitrifying and heterotrophic bacteria in soil columns.the enhanced mineralization of immobilized nitrogen by bacteriophagous protozoa has been thought to favor the nitrification process in soils in which nitrifying bacteria must compete with heterotrophic bacteria for the available ammonium. to obtain more insight into this process, the influence of grazing by the flagellate adriamonas peritocrescens on the competition for ammonium between the chemolithotrophic species nitrosomonas europaea and the heterotrophic species arthrobacter globiformis in ...199316348988
physicochemical cell surface and adhesive properties of coryneform bacteria related to the presence and chain length of mycolic acids.the presence and chain length of mycolic acids of bacteria of the genera corynebacterium, rhodococcus, gordona, mycobacterium, and arthrobacter and of coryneform bacteria containing a type b peptidoglycan were related to the cell surface hydrophobicity of the bacteria, which in turn was related to adhesion of the cells to defined surfaces such as teflon and glass. the origin of the overall negative charge of these bacteria is discussed.199316349100
effect of organic matter decomposition level on bacterial species diversity and composition in relationship to pythium damping-off severity.rhizosphere bacteria were isolated from root tip segments of cucumber seedlings grown in a suppressive, slightly decomposed light-colored peat mix, a conducive, more decomposed dark-colored peat mix, and a suppressive dark peat mix amended with composted hardwood bark. the bacteria were identified by a gas chromatographic fatty acid methyl ester analysis. the total number of taxa recovered from a single root tip segment ranged from 9 to 18. no single taxon predominated on all root tip segments h ...199316349117
toxicity of homologous series of organic solvents for the gram-positive bacteria arthrobacter and nocardia sp. and the gram-negative bacteria acinetobacter and pseudomonas sp.the toxicity of homologous series of organic solvents has been investigated for the gram-positive bacteria, arthrobacter sp. and nocardia sp., and the gram-negative bacteria, acinetobacter sp. and pseudomonas sp. the hydrophobicity of the solvent, expressed by its logp(octanol), proves to be a good measure for the toxicity of solvents in a two-phase system. the transition from toxic to nontoxic solvents occurs between logp(octanol) 3 and 5 and depends on the homologous series. no correlation has ...199318613108
growth-inhibition of t47d human breast-cancer cells by the new antiaromatase steroid 3-methylene-1,4-androstadien-17-one.the c19 steroid, 3-methylene-1,4-androstadien-17-one (3-methylene-1-dehydro-4-androsten-17-one, abbrev. 3mda) was synthesized by microbial dehydrogenation with arthrobacter simplex from the corresponding 1,2-saturated, 3-methylene-4-androsten-17-one. the new steroid induces a type-1 optical difference spectrum with cytochrome p450 aromatase from human placentae (k(s) 1.61 mum). kinetic inhibition studies with placental microsomes show: (i) 3mda inhibits aromatase irreversibly (k(inact) 0.026 min ...199321573449
changes in ester-linked phospholipid fatty acid profiles of subsurface bacteria during starvation and desiccation in a porous medium.ester-linked phospholipid fatty acid (plfa) profiles of a pseudomonas aureofaciens strain and an arthrobacter protophormiae strain, each isolated from a subsurface sediment, were quantified in a starvation experiment in a silica sand porous medium under moist and dry conditions. washed cells were added to sand microcosms and maintained under saturated conditions or subjected to desiccation by slow drying over a period of 16 days to final water potentials of approximately - 7.5 mpa for the p. aur ...199416349382
purification and characterization of 4-chlorobenzoyl coa dehalogenase from arthrobacter sp. strain 4-cb1.4-chlorobenzoyl coenzyme a dehalogenase was purified to homogeneity from arthrobacter sp. strain 4-cb1 (previously known as acinetobacter sp. strain 4-cb1), a bacterium isolated from pcb-contaminated soil. purification was accomplished by four chromatographic steps, including a novel affinity chromatography step. 4-chlorobenzoyl coa dehalogenase is a homotetramer of 33-kda subunits with an isoelectric point of 6.1. the enzyme is stable between ph 6.5 and 10. the optimum ph for kcat is ph 8. the ...19947918379
expression of a bacterial gene in transgenic plants confers resistance to the herbicide phenmedipham.tobacco plants were genetically engineered to express a detoxifying pathway for the herbicide phenmedipham. a gene from arthrobacter oxidans strain p52 that encodes an enzyme catalysing the hydrolytic cleavage of the carbamate compound phenmedipham has recently been cloned and sequenced. the coding sequence was fused with a cauliflower mosaic virus 35s promoter and introduced into tobacco plants by agrobacterium-mediated gene transfer. transgenic plants expressing high levels of phenmedipham hyd ...19947919217
structure of cell wall mannan of candida kefyr ifo 0586.we conducted a structural analysis of the antigenic cell wall mannoprotein (mannan) isolated from candida kefyr (formerly candida pseudotropicalis) ifo 0586. the result of two-dimensional homonuclear hartmann-hahn analysis of this mannan indicates that the molecule is constructed from alpha-1,2- and alpha-1,6-linked mannopyranose residues. upon alkali treatment (beta-elimination reaction), this mannan released two alpha-1,2-linked mannooligosaccharides, biose and triose. the structure of the alk ...19947927705
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