PMID(sorted descending)
16s rdna sequence analysis of culturable marine biofilm forming bacteria from a ship's hull.marine bacteria from the hull of a ship in the form of biofilms or microfouling were isolated, cultured, and identified by phylogenetic analysis using 16s rdna sequences. with an average length of 946 bp, all the 16 sequences were classified using the ribosomal database project (rdp) and were submitted to the national center for biotechnology information. phylogenetic analysis using 16s rdna sequences indicated that the 16 strains belonged to the firmicutes (ik-mb6 exiguobacterium aurantiacum, i ...201021038149
transgenic tobacco plants expressing atza exhibit resistance and strong ability to degrade atrazine.atrazine chlorohydrolase (atza) catalyzes hydrolytic dechlorination and can be used in detoxification of atrazine, a herbicide widely employed in the control of broadleaf weeds. in this study, to investigate the potential use of transgenic tobacco plants for phytoremediation of atrazine, atza genes from pseudomonas sp. strain adp and arthrobacter strain ad1 were transferred into tobacco. three and four transgenic lines, expressing atza-adp and atza-ad1, respectively, were produced by agrobacteri ...201020960204
direct cellular lysis/protein extraction protocol for soil metaproteomics.we present a novel direct protocol for deep proteome characterization of microorganisms in soil. the method employs thermally assisted detergent-based cellular lysis (sds) of soil samples, followed by tca precipitation for proteome extraction/cleanup prior to liquid chromatography-mass spectrometric characterization. this approach was developed and optimized using different soils inoculated with genome-sequenced bacteria (gram-negative pseudomonas putida or gram-positive arthrobacter chloropheno ...201020954746
diversity and activity of cultivable aerobic planktonic bacteria of a saline lake located in sovata, romania.aerobic bacterial strains from the salt water of lake red (sovata, romania) were cultivated. more than half of the 80 strains were g(-) and formed motile straight rods. only a few strains produced acid from d-glucose and reduced nitrate to nitrite. optimum nacl concentration for growth varied between 5 and 15 % in the majority of the strains, so the isolates were regarded moderately halophilic. on the basis of the 16s rrna gene sequence similarity almost half of the strains were identified as me ...201020941581
appraising bacterial strains for rapid bod sensing--an empirical test to identify bacterial strains capable of reliably predicting real effluent bods.the measured response of rapid biochemical oxygen demand (bod) biosensors is often not identical to those measured using the conventional 5-day bod assay. this paper highlights the efficacy of using both glucose-glutamic acid (gga) and organisation for economic cooperation and development (oecd) bod standards as a rapid screen for microorganisms most likely to reliably predict real effluent bods when used in rapid bod devices. using these two synthetic bod standards, a microorganism was identifi ...201020938773
purification and characterization of inulin fructotransferase (dfa iii-forming) from arthrobacter aurescens sk 8.001.the soil bacterium arthrobacter aurescens sk 8.001 produces inulin fructotransferase (iftase), and liquid chromatography-mass spectrometry (lc-ms) and carbon-13 nuclear magnetic resonance (13c nmr) analysis demonstrated that the main product of the enzyme was difructose anhydride iii (dfa iii). the iftase was purified by ethanol precipitation, deae sepharose fast flow, and superdex 200 10/300 gl gel chromatography. its molecular mass was estimated to be 40 kda by sds-page and 35 kda by gel filtr ...201020933390
identification of chitinases is-chia and is-chib from isoptericola jiangsuensis clg and their characterization.a 274-bp conserved fragment of chia (chia-cf) was amplified from the genomic dna of isoptericola jiangsuensis clg (dsm 21863, cctcc ab208287) using the specific pcr primers. based on chia-cf sequences, a 5233-bp dna fragment was obtained by self-formed adaptor pcr. dna sequencing analysis revealed there were two contiguous open reading frames coding for the precursors of is-chia [871 amino acids (aa)] and is-chib (561 aa) in the 5233-bp dna fragment. the is-chia and is-chib exhibited 58% and 62% ...201020922373
bacterial community diversity in the brazilian atlantic forest soils.the aim of this study was to characterize the bacterial community diversity of the brazilian atlantic forest soil by means of both cultivation and 16s rrna clone libraries. a collection of 86 representative isolates, obtained from six samples of atlantic forest soils from the national park of serra dos órgãos (parnaso), belonged to the genera arthrobacter, bacillus, burkholderia, leifsonia, paenibacillus, pseudomonas, ralstonia, serratia, and streptomyces according to the 16s rrna sequences. rep ...201020886336
[xylose isomerase constitutive biosynthesis in arthrobacter nicotianae].the specific features of biosynthesis of the cell-bound xylose isomerase by the actinobacterium arthrobacter nicotianae bim v-5 were studied. it was demonstrated that the constitutive synthesis of this enzyme in the studied bacteria, not subject to catabolite repression, was inhibited by xylulose, an intermediate product ofxylose utilization and the final product of its enzymatic isomerization. short-term experiments demonstrated that xylulose at a concentration of 0.005% almost completely repre ...201020873168
arthrobacter equi sp. nov., a novel bacterium isolated from a veterinary clinical material.a gram-positive, aerobic, catalase-positive, non-spore-forming, rod-shaped bacterium, strain immib l-1606t, isolated from genital swabs of a horse was characterized using a polyphasic approach. comparative 16s rrna gene sequence analysis showed that the organism was related to the genus arthrobacter, displaying 93.5 - 99.1 % sequence similarities with established species of the genus. cell wall analysis revealed cell-wall peptidoglycan type a3α l-lys - l-ser - l-thr - l-ala. the results of dna-d ...201020870884
the catalytic efficiency of trehalose-6-phosphate synthase is effected by the n-loop at low temperatures.the enzyme otsa (trehalose-6-phosphate synthase) is ubiquitous in both prokaryotic and eukaryotic organisms, where it plays a critical role in stress resistance and glucose metabolism. here, we cloned the otsa gene from arthrobacter sp. cjts, and expressed and then purified the recombinant proteins. enzyme activity analysis indicated that the high catalytic efficiency of otsa from arthrobacter sp. cjts resulted from the high affinity of the enzyme for uridine 5'-diphosphoglucose (udp-glc) at low ...201020838774
phytoremediation of mercury in pristine and crude oil contaminated soils: contributions of rhizobacteria and their host plants to mercury removal.the rhizospheric soils of three tested legume crops: broad beans (vicia faba), beans (phaseolus vulgaris) and pea (pisum sativum), and two nonlegume crops: cucumber (cucumis sativus) and tomato, (lycopersicon esculentum) contained considerable numbers (the magnitude of 10(5)g(-1) soil) of bacteria with the combined potential for hydrocarbon-utilization and mercury-resistance. sequencing of the 16s rrna coding genes of rhizobacteria associated with broad beans revealed that they were affiliated t ...201020833430
novel isonitrile hydratase involved in isonitrile metabolism.we previously discovered n-substituted formamide deformylase (nfda) in arthrobacter pascens f164, which degrades n-substituted formamide (fukatsu, h., hashimoto, y., goda, m., higashibata, h., and kobayashi, m. (2004) proc. natl. acad. sci. u.s.a. 101, 13726-13731). in this study, we found an enzyme involved in the first step of isonitrile metabolism, isonitrile hydratase, that hydrates isonitrile to the corresponding n-substituted formamide. first, we investigated the optimum culture conditions ...201020826798
isolation and characterization of a pseudomonas sp. strain iitr01 capable of degrading α-endosulfan and endosulfan isolate bacteria capable of degrading endosulfan (es) and the more toxic es sulfate and to characterize their metabolites.201020825519
diversity of cold-active protease-producing bacteria from arctic terrestrial and marine environments revealed by enrichment culture.a new approach for enrichment culture was applied to obtain cold-active protease-producing bacteria for marine and terrestrial samples from svalbard, norway. the method was developed for the enrichment of bacteria by long-term incubation at low temperatures in semi-solid agar medium containing meat pieces as the main source of carbon and energy. zobell and 0.1x nutrient broth were added for marine and terrestrial microorganisms, respectively, to supply basal elements for growth. one to three typ ...201020799082
isolation and characterization of hexavalent chromium-reducing rhizospheric bacteria from a wetland.scirpus americanus pers. occurs naturally in "san germán," a pond that serves as a receptor of industrial wastewater in guanajuato, méxico. this plant accumulates metals mainly in the root: concentrations (mg/kg) of cr, as, cd and se were 970, 49, 41, and 85 respectively. analysis of rhizosphere samples indicated bacterial population of 10(8) cfu g(-1) in media with 0.2 mm cr(vi) and 10 mm sodium gluconate. thirteen isolates were obtained and phylogenetic analyses (16s rrna) indicated they corre ...201020734910
engineering host cell lines to reduce terminal sialylation of secreted antibodies.covalently-linked glycans on proteins have many functional roles, some of which are still not completely understood. antibodies have a very specific glycan modification in the fc region that is required for mediating immune effector functions. these fc glycans are typically highly heterogeneous in structure, and this heterogeneity is influenced by many factors, such as type of cellular host and rate of ab secretion. glycan heterogeneity can affect the fc-dependent activities of antibodies. it ha ...201020716959
characterization of a bacterial community from a northeast siberian seacoast permafrost sample.a combination of culture-dependent and -independent techniques was used to characterize a bacterial community, examine cold adaptation of isocitrate lyase (icl) genes, and detect genes with important ecological functions in a permafrost sample from the bykovsky peninsula on the laptev sea coast of northeast siberia. according to the 16s rrna gene sequence, 47 of the cultured isolates were members of the phyla firmicutes, proteobacteria, and actinobacteria, with 85% of the isolates belonging to t ...201020695892
isolation and characterization of an arthrobacter sp. strain hb-5 that transforms atrazine.a bacterial strain (hb-5) capable of utilizing atrazine as sole carbon and nitrogen source for growth was isolated from an industrial wastewater sample by enrichment culture. the isolate was identified as arthrobacter sp. according to its phenotypic features, physiologic and biochemical characteristics, and phylogenetic analysis. the strain exhibited faster atrazine degradation rates in atrazine-containing mineral media than the well-characterized atrazine-degrading bacteria pseudomonas sp. adp. ...201120686824
biodegradation of 4-chlorophenol by arthrobacter chlorophenolicus a6: effect of culture conditions and degradation kinetics.among known microbial species, arthrobacter chlorophenolicus a6 has shown very good potential to treat phenolic wastewaters. in this study, the levels of various culture conditions, namely initial ph, agitation (rpm), temperature (°c), and inoculum age (h) were optimized to enhance 4-chlorophenol (4-cp) biodegradation and the culture specific growth rate. for optimization, central composite design of experiments followed by response surface methodology (rsm) was applied. results showed that amon ...201120676733
a novel replicative enzyme encoded by the linear arthrobacter plasmid pal1.the soil bacterium arthrobacter nitroguajacolicus rü61a contains the linear plasmid pal1, which codes for the degradation of 2-methylquinoline. like other linear replicons of actinomycetes, pal1 is characterized by short terminal inverted-repeat sequences and terminal proteins (tppal1) covalently attached to its 5' ends. tppal1, encoded by the pal1.102 gene, interacts in vivo with the protein encoded by pal1.101. bioinformatic analysis of the pal1.101 protein, which comprises 1,707 amino acids, ...201020675469
air-cathode microbial fuel cell array: a device for identifying and characterizing electrochemically active microbes.microbial fuel cells (mfcs) have generated excitement in environmental and bioenergy communities due to their potential for coupling wastewater treatment with energy generation and powering diverse devices. the pursuit of strategies such as improving microbial cultivation practices and optimizing mfc devices has increased power generating capacities of mfcs. however, surprisingly few microbial species with electrochemical activity in mfcs have been identified because current devices do not suppo ...201120655725
reversible immobilization of uricase on conductive polyaniline brushes grafted on polyacrylonitrile film.polyacrylonitrile film (pan) surfaces were modified with chemical polymerization of conductive polyaniline (pani) in the presence of potassium dichromate as an oxidizing agent. the conductive films were used for immobilization of uricase. the surface resistance of the conductive film in this work was found to be 0.97 kω/cm. the maximum amount of immobilized enzyme on conductive film containing 2.4% pani was about 216 μg/cm(2). the optimum ph for free and immobilized enzymes was observed at 7.0 a ...201120652599
chemical composition and antibacterial activity of essential oils of lantana camara, ageratum houstonianum and eupatorium adenophorum.essential oils have applications in folk medicine, food preservation, and as feed additives. the essential oils of lantana camara linn. (verbenaceae), ageratum houstonianum mill. (asteraceae) and eupatorium adenophorum spreng. (asteraceae) were analyzed by gas chromatography-mass spectrometry (gcms). in l. camara oil, of the total identified (83.91%) volatile constituents, five constituents [3,7,11-trimethyl-1,6,10-dodecatriene (28.86%), beta-caryophyllene (12.28%), zingiberene (7.63%), gamma-cu ...201020645797
study on the removal of indoor vocs using biotechnology.with the improvement of living standard and civil building innovation, large numbers of building materials and decoration are being used. the emission of gaseous organic pollutants such as formaldehyde, benzene, toluene and xylene from these materials may trigger immediate or persistent potential harm to human health. in this study, with the combination of bake-out exhaust, biological treatment was applied to deal with volatile organic compounds (vocs). four bacterial strains were isolated from ...201020598440
prevalence of the gene trzn and biogeographic patterns among atrazine-degrading bacteria isolated from 13 colombian agricultural soils.the following study evaluated the diversity and biogeography of 83 new atrazine-degrading bacteria and the composition of their atrazine degradation genes. these strains were isolated from 13 agricultural soils and grouped according to rep-pcr genomic fingerprinting into 11 major clusters, which showed biogeographic patterns. three clusters (54 strains) belonged to the genus arthrobacter, seven clusters (28 strains) were similar to the genus nocardioides and only one strain was a gram-negative f ...201020597985
variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination--determination of toxicity thresholds.freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. tests were performed with bacteria (arthrobacter globiformis), yeast (saccharomyces cerevisiae), nematodes (caenorhabditis elegans), oligochaetes (lumbriculus variegatus), higher plants (myriophyllum aquaticum), and the e ...201020594629
investigation of mineral water springs of miercurea ciuc (csíkszereda) region (romania) with cultivation-dependent microbiological methods.water samples of ten mineral water springs at miercurea ciuc (csíkszereda) region (romania) were examined during 2005-2006 using cultivation-dependent microbiological methods. the results of standard hygienic bacteriological tests showed that the hargita spring had perfect and five other springs had microbiologically acceptable water quality (zsögöd-, nagy-borvíz-, taploca-, szentegyháza- and lobogó springs). the water of borsáros spring was exceptionable (high germ count, presence of enterococc ...201020587384
high-density polyethylene (hdpe)-degrading potential bacteria from marine ecosystem of gulf of mannar, india.assessment of high-density polyethylene (hdpe)-degrading bacteria isolated from plastic waste dumpsites of gulf of mannar.201020586938
structural and kinetic studies on the ser101ala variant of choline oxidase: catalysis by compromise.the oxidation of choline catalyzed by choline oxidase includes two reductive half-reactions where fad is reduced by the alcohol substrate and by an aldehyde intermediate transiently formed in the reaction. each reductive half-reaction is followed by an oxidative half-reaction where the reduced flavin is oxidized by oxygen. here, we have used mutagenesis to prepare the ser101ala mutant of choline oxidase and have investigated the impact of this mutation on the structural and kinetic properties of ...201020561507
influence of ph and inorganic phosphate on toxicity of zinc to arthrobacter sp. isolated from heavy-metal-contaminated sediments.because of its high solubility over a wide range of ph conditions, zinc is found in many natural and human-impacted systems. zinc speciation is critical in assessing zinc toxicity to microorganisms because it varies considerably with ph and is dependent on other aqueous constituents. combined results of thermodynamic modeling, statistical analysis, and batch culture studies using arthrobacter sp. jm018 suggest that the toxic species may not be solely limited to the free ion, but also includes zn ...201020553043
weathering-associated bacteria from the damma glacier forefield: physiological capabilities and impact on granite dissolution.several bacterial strains isolated from granitic rock material in front of the damma glacier (central swiss alps) were shown (i) to grow in the presence of granite powder and a glucose-nh(4)cl minimal medium without additional macro- or micronutrients and (ii) to produce weathering-associated agents. in particular, four bacterial isolates (one isolate each of arthrobacter sp., janthinobacterium sp., leifsonia sp., and polaromonas sp.) were weathering associated. in comparison to what was observe ...201020525872
arthrobacter livingstonensis sp. nov. and arthrobacter cryotolerans sp. nov., salt-tolerant and psychrotolerant species from antarctic soil.two novel cold-tolerant, gram-stain-positive, motile, facultatively anaerobic bacterial strains, li2(t) and li3(t), were isolated from moss-covered soil from livingston island, antarctica, near the bulgarian station st kliment ohridski. a rod-coccus cycle was observed for both strains. 16s rrna gene sequence analysis revealed an affiliation to the genus arthrobacter, with the highest similarity to arthrobacter stackebrandtii and arthrobacter psychrochitiniphilus for strain li2(t) (97.8 and 97.7  ...201120511467
[investigation of biotechnological strains of microorganisms for their hygienic standardization].by analyzing the findings and databases on the hygienic standardization of industrial microorganisms, the authors have improved a research program for industrial strains on substantiating their safe exposure levels in workplace and ambient airs. a shortened program is proposed to investigate gram-positive bacteria and nocardioformic actinomycetes (lactobacillus, micrococcus, propionibacterim, brevibacterim, rhodococcus), which have no negative effect. it is necessary to study gram-negative bacte ...201020491276
arthrobacter endo-beta-n-acetylglucosaminidase shows transglycosylation activity on complex-type n-glycan oxazolines: one-pot conversion of ribonuclease b to sialylated ribonuclease c. 201020486148
engineering of choline oxidase from arthrobacter nicotianae for potential use as biological bleach in order to engineer the choline oxidase from arthrobacter nicotianae (an_coda) for the potential application as biological bleach in detergents, the specific activity of the enzyme toward the synthetic substrate tris-(2-hydroxyethyl)-methylammonium methylsulfate (mtea) was improved by methods of directed evolution and rational design. the best mutants (up to 520% wt-activity with mtea) revealed mutations in the fad- (a21v, g62d, i69v) and substrate-binding site (s348l, v349l, f351y). in a separ ...201020467737
calcite-forming bacteria for compressive strength improvement in mortar.microbiological calcium carbonate precipitation (mcp) has been investigated for its ability to improve the compressive strength of concrete mortar. however, very few studies have been conducted on the use of calcite-forming bacteria (cfb) to improve compressive strength. in this study, we discovered new bacterial genera that are capable of improving the compressive strength of concrete mortar. we isolated 4 cfb from 7 environmental concrete structures. using sequence analysis of the 16s rrna gen ...201020467254
the type of cheese curds determined the colouring capacity of brevibacterium and arthrobacter species.this study compares the colouring capacity of brevibacterium aurantiacum (ba), brevibacterium bl and arthrobacter species as in relation to deacidified media made from lactic curd (epoisses), mixed curds (munster) and rennet curds (livarot or reblochon). ba colouring capacity proved to be constant, leading to a dark orange colour, irrespective of the deacidified media. however, it gave too dark a colour for reblochon. the strains bl and as were not adapted to the colouring of epoisses deacidifie ...201020462468
the microbe-mineral environment and gypsum neogenesis in a weathered polar evaporite.evaporitic deposits are a globally widespread habitat for micro-organisms. the microbe-mineral environment in weathered and remobilized gypsum from exposed mid-ordovician marine evaporite beds in the polar desert of devon island, nunavut, canadian high arctic was examined. the gypsum is characterized by internal green zones of cyanobacterial colonization (dominated by gloeocapsa/aphanothece and chroococcidiopsis spp. morphotypes) and abundant black zones, visible from the surface, that contain p ...201020456500
rescuing of the hydride transfer reaction in the glu312asp variant of choline oxidase by a substrate the active site of choline oxidase, glu312 participates in binding the trimethylammonium group of choline, thereby positioning the alcohol substrate properly for efficient hydride transfer to the enzyme-bound flavin. previous studies have shown that substitution of glu312 with aspartate results in a perturbed mechanism of hydride transfer, with a 260-fold decrease in the rate associated with the mutation. here, the reaction of alcohol oxidation catalyzed by the glu312asp enzyme has been inves ...201020447376
homology modeling and docking study of xanthine oxidase of arthrobacter sp. xl26.hyperuricemia is a condition of defective purine metabolism characterized with elevated serum uric acid (ua) level that further leads to gout and gouty nephrolithiasis disorders. gout is a world wide distributed rheumatic disease comprises 1% of the total population and still is in increasing state. one of the factors contributing to overproduction of ua is the hydroxylation of xanthine catalyzed by xanthine oxidase (xo). in the present study, 3d modeling of arthrobacter sp. xl26 (xodb) protein ...201020403378
comparative study of properties of immobilized lipase onto glutaraldehyde-activated amino-silica gel via different methods.the enzyme-aggregate coating method was performed to immobilize arthrobacter sp. lipase in order to achieve better catalytic properties comparable to the conventional covalent attachment and covalent attachment plus cross-linking. the glutaraldehyde-activated amino-silica gel which was synthesized by sol-gel technique was used as the support, and the catalytic characteristics of the lipase preparations were tested in the asymmetric acylation of 4-hydroxy-3-methyl-2-(2-propenyl)-2-cyclopenten-1-o ...201020399626
glycosylation patterns of human alpha2-macroglobulin: analysis of lectin binding by electron microscopy.human alpha2-macroglobulin (alpha 2m) is a 720 kda glycoprotein that presents two ultrastructural conformations: slow (s-alpha 2m) and fast (f-alpha 2m). alpha 2m acts mainly as a proteinase scavenger, but an immunomodulatory role was also proposed. this work studies the effect of desialylation and deglycosylation on the structure patterns of alpha 2m by ultrastructural analysis of lectin-induced aggregates, which represents a new approach that had never been previously used. transmission electr ...201020399104
[isolation and identification of a fibrinolytic bacterium strain from frozen soil in the tibetan plateau].cardiovascular disease, harmful to human health, is a worldwide disease, for which fibrinolytic enzyme is usually used as an effective remedy. fibrinolytic microbes under extreme environmental conditions may excrete some high efficient and safe fibrinolytic enzymes. so, for obtaining this fibrinolytic enzyme, we isolated fibrinolytic strains from frozen soil in the tibetan plateau.201020387455
aepa of pectobacterium is not involved in the regulation of extracellular plant cell wall degrading enzymes production.plant cell wall degrading enzymes (pcwde) are the major virulence determinants in phytopathogenic pectobacterium, and their production is controlled by many regulatory factors. in this study, we focus on the role of the aepa protein, which was previously described to be a global regulator of pcwde production in pectobacterium carotovorum (murata et al. in mol plant microbe interact 4:239-246, 1991). our results show that neither inactivation nor overexpression of aepa affects pcwde production in ...201020386924
culture-dependent and culture-independent diversity of actinobacteria associated with the marine sponge hymeniacidon perleve from the south china this report, the diversity of actinobacteria associated with the marine sponge hymeniacidon perleve collected from a remote island of the south china sea was investigated employing classical cultivation and characterization, 16s rdna library construction, 16s rdna-restriction fragment length polymorphism (rdna-rflp) and phylogenetic analysis. a total of 184 strains were isolated using seven different media and 24 isolates were selected according to their morphological characteristics for phyl ...201020383659
structural characterization of the major glycolipids from arthrobacter globiformis and arthrobacter scleromae.arthrobacter is a genus of gram-positive bacteria widely distributed in soil. the ability to catabolize a variety of xenobiotics has shown their potential as a detoxifying agent. recently, arthrobacter has been also recognized as an opportunistic pathogen. glycolipids from a. scleromae, a clinical isolate, and a. globiformis, from soil, were isolated by chloroform-methanol extraction and subsequently purified using column chromatography and high-performance liquid chromatography. structural stud ...201020381794
cg2091 encodes a polyphosphate/atp-dependent glucokinase of corynebacterium glutamicum.the corynebacterium glutamicum gene cg2091 is encoding a polyphosphate (polyp)/atp-dependent glucokinase (ppgk). previous work demonstrated the association of ppgk to polyp granules. the deduced amino acid sequence of ppgk shows 45% sequence identity to polyp/atp glucomannokinase of arthrobacter sp. strain km and 50% sequence identity to polyp glucokinase of mycobacterium tuberculosis h37rv. ppgk from c. glutamicum was purified from recombinant escherichia coli. polyp was highly preferred over a ...201020379711
aerobic biodegradation of a sulfonated phenylazonaphthol dye by a bacterial community immobilized in a multistage packed-bed bac reactor.a microbial community able to aerobically degrade the azo dye acid orange 7 was selected from riparian or lacustrine sediments collected at sites receiving textile wastewaters. three bacterial strains, pertaining to the genera pseudomonas, arthrobacter, and rhizobium, constitute the selected community. the biodegradation of ao7 was carried out in batch-suspended cell culture and in a continuously operated multistage packed-bed bac reactor. the rapid decolorization observed in batch culture, join ...201020376575
arthrobacter sp. strain ku001 isolated from a thai soil degrades atrazine in the presence of inorganic nitrogen atrazine degrading bacterium, strain ku001, was obtained from a sugarcane field at the cane and sugar research and development center at the kasetsart university, kamphaeng saen campus, thailand. strain ku001 had a rod-to-coccus morphological cycle during growth. biolog carbon source analysis indicated that the isolated bacterium was arthrobacter histidinolovorans. sequence analysis of pcr product indicated the 16s rrna gene in strain ku001 was 99% identical to the same region in arthrobacter ...201020372034
esmond e. snell--the pathfinder of b vitamins and cofactors.esmond e. snell (1914-2003) was a giant of b-vitamin and enzyme research. his early research in bacterial nutrition had lead to the discovery of vitamins such as lipoic acid and folic acid, and an anti-vitamin avidin. he developed microbiological assay methods for riboflavin and other vitamins and amino acids, which are still used today. he also investigated the metabolism of vitamins, discovered pyridoxal and pyridoxamine as the active forms of vitamin b(6) and revealed the mechanism of transam ...201020353954
strains of internal biofilm in aerobic granular membrane bioreactors.this study isolated strains in suspended liquor, the surface fouling layer, and biofilm inside hollow-fiber membranes of a membrane bioreactor (mbr); analyzed their distributions, sizes, surface charges, and growth behaviors; and determined the quantities of extracellular polymeric substances (eps) secreted by these strains under different organic loadings. three strains, which may penetrate the microfiltration membranes, were close relatives of the ralstonia mannitolilytica strain sdv (genbank ...201020306189
crystallization and preliminary crystallographic analysis of manganese(ii)-dependent 2,3-dihydroxybiphenyl 1,2-dioxygenase from bacillus sp. jf8.a thermostable manganese(ii)-dependent 2,3-dihydroxybiphenyl-1,2-dioxygenase derived from bacillus sp. jf8 was crystallized. the initial screening for crystallization was performed by the sitting-drop vapour-diffusion method using a crystallization robot, resulting in the growth of two crystal forms. the first crystal belonged to space group p1, with unit-cell parameters a = 62.7, b = 71.4, c = 93.6 a, alpha = 71.2, beta = 81.0, gamma = 64.0 degrees, and diffracted to 1.3 a resolution. the secon ...201020208161
role of valine 464 in the flavin oxidation reaction catalyzed by choline oxidase.the oxidation of reduced flavin cofactors by oxygen is a very important reaction that is central to the chemical versatility of hundreds of flavoproteins classified as monooxygenases and oxidases. these enzymes are characterized by bimolecular rate constants >or=10(5) m(-1) s(-1) and produce water and hydrogen peroxide, respectively. a hydrophobic cavity close to the reactive flavin c(4a) atom has been previously identified in the 3d structure of monooxygenases but not in flavoprotein oxidases. ...201020184377
c, n, and h isotope fractionation of the herbicide isoproturon reflects different microbial transformation pathways.the fate of pesticides in the subsurface is of great interest to the public, industry, and regulatory authorities. compound-specific isotope analysis (csia) is a promising tool complementary to existing methods for elucidating pesticide degradation reactions. here, we address three different initial biotransformation reactions of the phenylurea herbicide isoproturon (3-(4-isopropylphenyl)-1,1-dimethylurea) in pure culture experiments with bacterial and fungal strains. when analyzing isotopic cha ...201020184312
identification of airborne bacterial and fungal species in the clinical microbiology laboratory of a university teaching hospital employing ribosomal dna (rdna) pcr and gene sequencing techniques.universal or "broad-range" pcr-based ribosomal dna (rdna) was performed on a collection of 58 isolates (n = 30 bacteria + 28 fungi), originating from environmental air from several locations within a busy clinical microbiology laboratory, supporting a university teaching hospital. a total of 10 bacterial genera were identified including both gram-positive and gram-negative genera. gram-positive organisms accounted for 27/30 (90%) of total bacterial species, consisting of seven genera and include ...200920183192
biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. among the various bioactive compounds, biosurfactant (bs)/bioemulsifiers (be) are attracting major interest and attention due to their structural and functional diversity. the versatile properties of surface active molecules find numerous applications in various industries. marine microorganisms such as acinetobacter, arthrobacter, pseudomonas, halomonas, ...201020172021
one-pot conversion of levan prepared from serratia levanicum nn to difructose anhydride iv by arthrobacter nicotinovorans levan fructotransferase.the newly established difructose anhydride iv (dfa iv) production system is comprised of the effective production of levan from sucrose by serratia levanicum nn, the conversion of the levan into dfa iv by levan fructotransferase from arthrobacter nicotinovorans gs-9, which is highly expressed in an escherichiacoli transformant, and a practical purification step. the chemical properties of dfa iv were also investigated.201020159571
the biomass yielding process of xenobiotic degradation.yields of activated sludge and an arthrobacter sp. biomass on organic xenobiotic 2,4-dichlorophenoxyacetic acid (2,4-d) and on the intermediates of selected 2,4-d metabolism pathways were measured. activated sludge yield on 2,4-d was lower by approximately 24-45% compared to the combined yields produced separately by the lower intermediates. for activated sludge, cell synthesis only consumed 33% of the electrons generated from 2,4-d oxidation, while the other 67% were used for energy. the high e ...201020153175
identification and in vitro deoxynucleotidylation of the terminal protein of the linear plasmid pal1 of arthrobacter nitroguajacolicus rü61a.the plasmid pal1 of arthrobacter nitroguajacolicus rü61a is a linear replicon, characterized by inverted terminal repeats and terminal proteins (tps) covalently bound to its 5'-ends. previous sequence analysis and predictions of possible secondary structures formed by telomeric 3'-overhangs indicated significant differences of the 'left' and 'right' telomere of pal1, raising the question of whether each terminus is recognized by a specific protein. the genes pal1.102 and pal1.103, located close ...201020141532
mechanism of boron tolerance in soil bacteria.boron (b) is toxic to living cells at levels above a certain threshold. we isolated several b-tolerant bacterial strains from soil samples and studied them for possible mechanisms of b tolerance. 16s rrna gene sequencing and comparative phylogenetic analysis demonstrated that the isolates belong to the following 6 genera: arthrobacter, rhodococcus, lysinibacillus, algoriphagus, gracilibacillus, and bacillus. these isolates exhibited b-tolerance levels of 80, 100, 150, 300, 450, and 450 mmol/l, r ...201020130690
copy number determination, expression analysis of genes potentially involved in replication, and stability assays of pal1 - the linear megaplasmid of arthrobacter nitroguajacolicus rü61a.pal1 of the actinomycete arthrobacter nitroguajacolicus rü61a, a 113-kb catabolic linear megaplasmid of the invertron-type, enables its host to utilize quinaldine (or 4-hydroxyquinaldine) as the sole carbon and energy source. comparative southern hybridization and quantitative real-time pcr analyses revealed copy numbers of two for cells grown in minimal medium supplemented with 4-hydroxyquinaldine and four for cells cultivated in luria-bertani medium. however, medium-dependent differences in th ...201120116226
identification and characterization of bacteria isolated under selective pressure of volatile organic compounds.several bacterial strains tolerant to volatile organic compounds (vocs) were isolated from the air emissions of a typical industrial wood painting plant. four strains that grew vigorously on a mineral salt basal medium and voc-saturated atmosphere were identified using biolog and fatty acids analysis. a 16s rdna sequence comparison was also performed on three of the four strains. their phylogenetic positions were respectively: mc8m6 of the genus arthrobacter mcep3 of the genus microbacterium, mc ...200920112870
influence of internal biofilm growth on residual permeability loss in aerobic granular membrane bioreactors.membrane fouling results in flux decline or transmembrane pressure drop increase during membrane bioreactor (mbr) operation. physical and chemical cleanings are essential to keep an mbr operating at an appropriate membrane flux. considerable residual membrane permeability loss that cannot be removed by conventional cleaning requires membrane replacement. this study demonstrates that an internal biofilm can develop inside a hollow-fiber membrane and can probably account for up to 58.9 and 81.3% o ...201020102183
biotransformation of nicotine by microorganism: the case of pseudomonas spp.several bacterial species are capable of using nicotine, the main alkaloid in tobacco plants, as a substrate for growth. the dominant species include members of two genera, pseudomonas and arthrobacter. the degradation pathway and genetic structure of nicotine catabolism in arthrobacter nicotinovorans were recently reviewed (brandsch appl microbiol biotechnol 69:493-498, 2006). here, we present up-to-date information on biodegradation of nicotine by pseudomonas spp. species in this genus capable ...201020091027
phylogenetic diversity of alkaline protease-producing psychrotrophic bacteria from glacier and cold environments of lahaul and spiti, india.the diversity of proteolytic bacteria associated with a glacier and cold environment soils from three different locations in lahaul and spiti, india was investigated. two hundred seventeen bacterial strains were isolated in pure culture. subsequently these strains were screened for protease-production and one hundred nine showed protease production. from these protease producing psychrotrophic bacteria twenty showing high enzyme production at low temperature and alkaline ph were characterized an ...201020082368
structural basis for cofactor-independent dioxygenation of n-heteroaromatic compounds at the alpha/beta-hydrolase fold.enzymatic catalysis of oxygenation reactions in the absence of metal or organic cofactors is a considerable biochemical challenge. the co-forming 1-h-3-hydroxy-4-oxoquinaldine 2,4-dioxygenase (hod) from arthrobacter nitroguajacolicus rü61a and 1-h-3-hydroxy-4-oxoquinoline 2,4-dioxygenase (qdo) from pseudomonas putida 33/1 are homologous cofactor-independent dioxygenases involved in the breakdown of n-heteroaromatic compounds. to date, they are the only dioxygenases suggested to belong to the alp ...201020080731
genetic and phenotypic diversity of parathion-degrading bacteria isolated from rice paddy soils.three parathion-degrading bacteria and eight pairs of bacteria showing syntrophic metabolism of parathion were isolated from rice field soils, and their genetic and phenotypic characteristics were investigated. the three isolates and eight syntrophic pairs were able to utilize parathion as a sole source of carbon and energy, producing p-nitrophenol as the intermediate metabolite during the complete degradation of parathion. analysis of 16s rrna gene sequence indicated that the isolates were rela ...200920075637
enhanced cyclic adenosine monophosphate production by arthrobacter a302 through rational redistribution of metabolic flux.cyclic adenosine monophosphate (camp) was synthesized through the purine salvage synthesis pathway by arthrobacter a302. results showed that hypoxanthine was the best of the precursors, and the camp concentration reached 4.06 g/l. for inhibition of the glycolytic pathway, sodium fluoride was found the optimal effector, which was further studied on camp production. with the addition of 0.4 g/l of sodium fluoride, the maximal camp concentration reached 11.04 g/l, and the concentrations of lactic a ...201020064709
growth of arthrobacter sp. strain jbh1 on nitroglycerin as the sole source of carbon and nitrogen.arthrobacter sp. strain jbh1 was isolated from nitroglycerin-contaminated soil by selective enrichment. detection of transient intermediates and simultaneous adaptation studies with potential intermediates indicated that the degradation pathway involves the conversion of nitroglycerin to glycerol via 1,2-dinitroglycerin and 1-mononitroglycerin, with concomitant release of nitrite. glycerol then serves as the source of carbon and energy.201020061454
heavy metal resistance in arthrobacter ramosus strain g2 isolated from mercuric salt-contaminated soil.present study describes isolation of a multiple metal-resistant arthrobacter ramosus strain from mercuric salt-contaminated soil. the isolate was found to resist and bioaccumulate several metals, such as cadmium, cobalt, zinc, chromium and mercury. maximum tolerated concentrations for above metals were found to be 37, 525, 348, 1530 and 369 microm, respectively. the isolate could also reduce and detoxify redox-active metals like chromium and mercury, indicating that it has great potential in bio ...201020060643
a polyphasic study on the species diversity of the sediment microbiota of lake hévíz.lake hévíz is the largest natural thermal lake of europe, harboring special bacterial communities. the aim of the present study was to gain information about the distribution and species diversity of the sediment microbiota, with special focus on actinobacteria, by using cultivation-based and -independent molecular methods. samples from two depths were taken in two different locations in october 2007. 245 strains were isolated, grouped to 85 otus by ardra, and identified by 16s rdna sequencing. ...200920038486
molecular identification of airborne bacteria associated with aerial spraying of bovine slurry waste employing 16s rrna gene pcr and gene sequencing techniques.polymerase chain reaction amplification of the universal 16s ribosomal rna (rrna) gene was performed on a collection of 38 bacterial isolates, originating from air sampled immediately adjacent to the agricultural spreading of bovine slurry. a total of 16 bacterial genera were identified including both gram-positive and gram-negative genera. gram-positive organisms accounted for 34/38 (89.5%) of total bacterial numbers consisting of 12 genera and included staphylococcus (most common genus isolate ...201020018377
crystal structure analysis of free and substrate-bound 6-hydroxy-l-nicotine oxidase from arthrobacter nicotinovorans.the pathway for oxidative degradation of nicotine in arthrobacter nicotinovorans includes two genetically and structurally unrelated flavoenzymes, 6-hydroxy-l-nicotine oxidase (6hlno) and 6-hydroxy-d-nicotine oxidase, which act with absolute stereospecificity on the l- and d-forms, respectively, of 6-hydroxy-nicotine. we solved the crystal structure of 6hlno at 1.95 a resolution by combined isomorphous/multiple-wavelength anomalous dispersion phasing. the overall structure of each subunit of the ...201020006620
isolation of an isocarbophos-degrading strain of arthrobacter sp. scl-2 and identification of the degradation pathway.isocarbophos is a widely used organophosphorus insecticide that has caused environmental pollution in many areas. however, degradation of isocarbophos by pure cultures has not been extensively studied, and the degradation pathway has not been determined. in this paper, a highly effective isocarbophos-degrading strain, scl-2, was isolated from isocarbophos-polluted soil. strain scl-2 was preliminarily identified as arthrobacter sp. based on its morphological, physiological, and biochemical proper ...200919996699
complete degradation of di-n-octyl phthalate by biochemical cooperation between gordonia sp. strain jdc-2 and arthrobacter sp. strain jdc-32 isolated from activated sludge.two bacterial strains were isolated from activated sludge using mixtures of phthalic acid esters (paes) as the sole source of carbon and energy. one of the isolates was identified as gordonia sp. strain jdc-2 and the other as arthrobacter sp. strain jdc-32, mainly through 16s rrna gene sequence analysis. gordonia sp. strain jdc-2 rapidly degraded di-n-octyl phthalate (dop) into phthalic acid (pa), which accumulated in the culture medium. arthrobacter sp. strain jdc-32 degraded pa but not dop. th ...201019959291
[lipolytic and catalase activity of bacteria-destructors of protective coatings].lipolytic and catalase activity of bacteria-destructors of protective coatings at different growth models: biofilm and plankton have been studied. it was shown that the synthesis of exoenzymes in the biofilm is different. activity of extracellular lipase and catalase in the biofilm is 1.1-1.5 and 1.2-2.1 times higher, respectively, than in plankton. the experiment duration being increased to 14 days, the lipolytic activity considerably decreases. activity of studied enzymes, produced by bacteria ...200919938616
[monosaccharide composition of exopolymer complex of bacteria-destructors of protective coatings].monosaccharide composition of exopolymer complex (epc) ofbacteria-destructors of protective coatings pseudomonas sp. t/, pseudomonas sp. 109, arthrobacter sp. 102 has been studied. it is established that monosaccharide composition of exopolymer complex of bacteria is different and depends on the bacteria growth model. it is mainly represented by penthoses and hexoses. glucose, galactose, arabinose, which are determined in epc of biofilm and plankton of all studied bacteria, are dominating monosa ...200919938612
[dynamics of microbial populations in the biofilm on protective coating].dynamics of microbial populations in the biofilm on the surface of protective coating poliken 980-25 has been studied. it was shown that in the process of succession one can observe some changes of taxonomic composition of biofilm bacteria. bacteria of pseudomonas genus were revealed at early stages of succession, they reduce fe+3 and oxidize carbohydrates. bacteria of arthrobacter genus begin developing 2 hours after the exposure, bacillus genus bacteria appear 6 hours after the experiment begi ...200919938604
antagonistic activity of bacteria isolated from crops cultivated in a rotation system and a monoculture against pythium debaryanum and fusarium oxysporum.the effect of crop rotation and monocropping on the occurrence of bacteria with antagonistic activity toward pythium debaryanum and fusarium oxysporum was shown. arthrobacter spp., fluorescent pseudomonas spp. and actinomycetes were isolated from winter rape, sugar beet and winter barley rhizosphere and bulk soil from the plots of a long-term crop rotation experiment (18 years). the occurrence of mycoantagonistic isolates and their antibiosis level exhibited specificity for the site, crop and cr ...200919937218
16s rrna gene-based identification of cultured bacterial flora from host-seeking ixodes ricinus, dermacentor reticulatus and haemaphysalis concinna ticks, vectors of vertebrate pathogens.a total of 151 bacterial isolates were recovered from different developmental stages (larvae, nymphs and adults) of field-collected ticks (67 strains from ixodes ricinus, 38 from dermacentor reticulatus, 46 from haemaphysalis concinna). microorganisms were identified by means of 16s rrna gene sequencing. almost 87 % of the strains belonged to g(+) bacteria with predominantly occurring genera bacillus and paenibacillus. other g(+) strains included arthrobacter, corynebacterium, frigoribacterium, ...200919937215
[isolation and identification of four dbp-degrading strains and molecular cloning of the degradation genes].four di-butyl-phthalate(dbp)-degrading bacterial strains, jdc-1, jdc-8, jdc-9 and jdc-12, were isolated from soil. the strains were gram positive. the 16s rrna sequence analysis revealed that the four strains had similarities of 99% with arthrobacter sp.. according to the morphologic, physiobiochemical characteristics and the analysis of their 16s rrna, all the four strains were identified as arthrobacter sp.. a 900 bp dna fragment was obtained from the four strains by pcr amplified and clone. w ...200919927831
c and n isotope fractionation suggests similar mechanisms of microbial atrazine transformation despite involvement of different enzymes (atza and trzn).transformation of atrazine to hydroxyatrazine in the environment may be underestimated by current assessment schemes since immobilization and further transformation of the metabolite can render parent-to-daughter compound ratios unreliable. this study reports significant c and n isotope fractionation of atrazine in transformation to hydroxyatrazine by chelatobacter heintzii, pseudomonas sp. adp, and arthrobacter aurescens tc1 highlighting an alternative approach to detecting this natural transfo ...200919924926
x-ray crystallographic analysis of the 6-aminohexanoate cyclic dimer hydrolase: catalytic mechanism and evolution of an enzyme responsible for nylon-6 byproduct degradation.we performed x-ray crystallographic analyses of the 6-aminohexanoate cyclic dimer (acd) hydrolase (nyla) from arthrobacter sp., an enzyme responsible for the degradation of the nylon-6 industry byproduct. the fold adopted by the 472-amino acid polypeptide generated a compact mixed alpha/beta fold, typically found in the amidase signature superfamily; this fold was especially similar to the fold of glutamyl-trna(gln) amidotransferase subunit a (z score, 49.4) and malonamidase e2 (z score, 44.8). ...201019889645
removal of organic compounds by a biofilm supported on gac: modelling of batch and column data.the performance of a biofilm of arthrobacter viscosus supported on granular activated carbon on the retention of organic compounds was evaluated. the presence of functional groups on the cell wall surface of the biomass that may interact with the organic compounds was confirmed by fourier transform infrared spectroscopy, to assess the applicability of this system to the removal of those compounds. the batch assays showed that the removal percentage decreases with the increasing initial concentra ...201019882356
arthrobacter alpinus sp. nov., a psychrophilic bacterium isolated from alpine aerobic, gram-reaction-positive, non-motile, psychrophilic bacterium, designated strain s6-3(t), was isolated from alpine soil. cells exhibited a rod-coccus growth cycle and produced a yellow pigment. growth occurred at 1-25 degrees c. phylogenetic analysis based on 16s rrna gene sequences showed that strain s6-3(t) was related to members of the genus arthrobacter, sharing highest sequence similarities with the type strains of arthrobacter psychrolactophilus (97.9 %) and arthrobacter stackebr ...201019880631
[genetic diversity of cultivable bacteria of dominant plants in a potassium mine tailing of nanjing].plant rhizosphere bacteria play an important role in biogeochemical cycles. microbial diversity of cultivable bacteria from soil-plant-mineral system in a mine tailing was assessed.200919873749
genetic diversity of phthalic acid esters-degrading bacteria isolated from different geographical regions of china.thirty-two strains of phthalic acid ester (paes)-degrading bacteria were isolated from thirteen geographically diverse sites by enrichment using mixtures of paes as the sole source of carbon and energy. sequence analyses of the 16s rrna gene indicated that these isolates were from six genera (arthrobacter, gordonia, rhodococcus, acinetobacter, pseudomonas, and delftia). to evaluate the genetic diversity among them, the molecular typing method rep-pcr with primers based on enterobacterial repetit ...201019866373
carbon nanotube clusters as universal bacterial adsorbents and magnetic separation agents.the magnetic susceptibility and high bacterial affinity of carbon nanotube (cnt) clusters highlight their great potential as a magnetic bio-separation agent. this article reports the cnt clusters' capability as "universal" bacterial adsorbents and magnetic separation agents by designing and testing a multiwalled carbon nanotube (mwnt) cluster-based process for bacterial capturing and separation. the reaction system consisted of large clusters of mwnts for bacterial capture and an external magnet ...201019856390
analysis of two gene clusters involved in the degradation of 4-fluorophenol by arthrobacter sp. strain if1.arthrobacter sp. strain if1 is able to grow on 4-fluorophenol (4-fp) as a sole source of carbon and energy. to clone the 4-fp degradation genes, dna libraries were constructed and screened with a probe obtained by pcr using primers designed on the basis of conserved regions of aromatic two-component monooxygenases. sequencing of positive clones yielded two gene clusters, each harboring a gene encoding a monooxygenase with high sequence similarity to the oxygenase component of 4-nitrophenol and 4 ...200919837837
[dormant form of micrococcus luteus and arthrobacter globiformis, not growing on standard media]. 200919827710
soil bacterial communities in constructed wetlands treated with swine wastewater using pcr-dgge technique.marsh-pond-marsh (mpm) constructed wetlands were designed for the treatment of swine wastewater. the goal of this study was to characterize bacterial communities in these wetlands and determine the nutrient removal from influent to effluent. surface soil samples were collected and analyzed by culture-dependent and culture-independent techniques. the results showed that the bacterial colony forming units (cfu) and the average concentrations of total nitrogen, nh(4)(+), total phosphorous (tp) and ...201019822421
arthrobacter antarcticus sp. nov., isolated from an antarctic marine sediment.a bacterial strain, spc26(t), was isolated from a sediment sample of the southern ocean off antarctica. the strain was gram-staining- and catalase-positive and contained lysine and alanine in the cell-wall peptidoglycan. the major cellular fatty acids were anteiso-c₁₅:₀ (54.92 %), iso-c₁₅:₀ (11.47 %), anteiso-c₁₇:₀ (6.48 %) and anteiso-c₁₅:₁ (6.38 %) and the major menaquinones were mk-8, mk-9 and mk-10. the major polar lipids were phosphatidylethanolamine and diphosphatidylglycerol. the g+c cont ...201019783612
characteristics and function of alcaligenes sp. nbrc 14130 esterase catalysing the stereo-selective hydrolysis of ethyl chrysanthemate.alcaligenes sp. nbrc 14130 was found as a strain hydrolysing a mixture of (+/-)-trans- and (+/-)-cis ethyl chrysanthemates to (1r,3r)-(+)-trans-chrysanthemic acid. the alcaligenes cells also have hydrolytic activity for 6-aminohexanoate-cyclic dimer (6-ahcd, 1,8-diazacyclotetradecane-2,9-dione). the correlation of function on the enzyme from the alcaligenes strain with hydrolysis activities for both ethyl chrysanthemate and 6-ahcd was demonstrated.201019778353
[biodehydrogenation of 11beta-hydroxyl melroxyprogesterone by arthrobacter simplex ur016 in microemulsion system].to improve mass transfer and enhance the yield for c(1,2) biodehydrogenation of steroid 11beta-hydroxyl medroxyprogesterone, we carried out the dehydrogenation reaction of 11beta-hydroxyl medroxyprogesterone in an oil-in-water (o/w) microemulsion by arthrobacter simplex ur016. we studied the effects of system composition, dehydrogenation temperature and substrate concentration on microbial transformation. we formulated a suitable o/w microemulsion system with arthrobacter simplex ur016 culture b ...200919777818
a new beta-galactosidase with a low temperature optimum isolated from the antarctic arthrobacter sp. 20b: gene cloning, purification and characterization.a psychrotrophic bacterium producing a cold-adapted beta-galactosidase upon growth at low temperatures was classified as arthrobacter sp. 20b. a genomic dna library of strain 20b introduced into escherichia coli top10f' and screening on x-gal (5-bromo-4-chloro-3-indolyl-beta-d-galactopyranoside)-containing agar plates led to the isolation of beta-galactosidase gene. the beta-galactosidase gene (bgas) encoding a protein of 1,053 amino acids, with a calculated molecular mass of 113,695 kda. analys ...200919771412
[catalytical properties of arthrobacter nicotianae cells, a producer of glucose isomerase, immobilized in xerogel of silicium dioxide].arthrobacter nicotinanae cells, producers of glucose isomerase, were immobilized in xerogel of silicium dioxide, and properties of the resulted heterogeneous biocatalysts were investigated in the process of isomerization of monosaccharide (glucose and fructose). the glucose isomerase activity of the resulted biocatalysts was shown to be 10 u/g, on average, taking into account the loss of the activity upon the immobilization, which amounted to 50% of the cell activity in suspension. the rate of t ...200919764612
high-level chromate resistance in arthrobacter sp. strain fb24 requires previously uncharacterized accessory genes.the genome of arthrobacter sp. strain fb24 contains a chromate resistance determinant (crd), consisting of a cluster of 8 genes located on a 10.6 kb fragment of a 96 kb plasmid. the crd includes chra, which encodes a putative chromate efflux protein, and three genes with amino acid similarities to the amino and carboxy termini of chrb, a putative regulatory protein. there are also three novel genes that have not been previously associated with chromate resistance in other bacteria; they encode a ...200919758450
the influence of host-guest inclusion complex formation on the biotransformation of cortisone acetate delta(1) intensive and systematic investigation had been carried out on the delta(1)-dehydrogenation of cortisone acetate (ca) to prednisone acetate (pa) by arthrobacter simplex tccc 11037 in the presence of native and modified beta-cyclodextrins (beta-cds). the biotransformation was improved through the formation of the host-guest inclusion complex between ca and cds in aqueous solution. the inclusion complexes of cds with ca were investigated by means of phase solubility, 2d nmr spectroscopy and dif ...200919744560
isolation and identification of novel microcystin-degrading bacteria.of 31 freshwater bacterial isolates screened using the biolog mt2 assay to determine their metabolism of the microcystin lr, 10 were positive. phylogenetic analysis (16s rrna) identified them as arthrobacter spp., brevibacterium sp., and rhodococcus sp. this is the first report of microcystin degraders that do not belong to the proteobacteria.200919734339
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