PMID(sorted descending)
fluorinated phenylcyclopropylamines. part 6: effects of electron withdrawing or donating aryl substituents on the inhibition of tyramine oxidase from arthrobacter sp. by diastereomeric 2-aryl-2-fluoro-cyclopropylamines.diastereomeric arylcyclopropylamines substituted with fluorine in the 2-position and with electron donating or electron withdrawing groups at the aromatic ring were evaluated as inhibitors of microbial tyramine oxidase. the trans-isomers were consistently more potent inhibitors of the enzyme than the cis-isomers. electron donating substituents increased the potency of tyramine oxidase inhibition, while electron withdrawing substituents decreased the activity. the results obtained are discussed i ...200819727324
impact of phenolic substrate and growth temperature on the arthrobacter chlorophenolicus proteome.we compared the arthrobacter chlorophenolicus proteome during growth on 4-chlorophenol, 4-nitrophenol, or phenol at 5 and 28 degrees c, both for the wild-type and a mutant strain with mass spectrometry based proteomics. a label-free workflow employing spectral counting identified 3749 proteins across all growth conditions, representing over 70% of the predicted genome and 739 of these proteins form the core proteome. statistically significant differences were found in the proteomes of cells grow ...200919714879
genetic and physiological diversity of phylogenetically and geographically distinct groups of arthrobacter isolated from lead-zinc mine tailings.the phylogenetic positions of 60 bacterial strains isolated from three tailing piles were determined by analyzing their partial 16s rrna gene sequences. these strains were divided into three phylogenetically distinct groups of arthrobacter and likely represented several non-described species. the physiological diversities of these phylogenetically and geographically distinct populations were evaluated based on their resistance to five heavy metals (zn, pb, cd, cu and co) and four antibiotics (ka ...200419712425
antarctic bacteria inhibit growth of food-borne microorganisms at low temperatures.the aim of this study was to identify antarctic microorganisms with the ability to produce cold-active antimicrobial compounds with potential for use in chilled food preservation. colonies (4496) were isolated from 12 antarctic soil samples and tested against listeria innocua, pseudomonas fragi and brochothrix thermosphacta. thirteen bacteria were confirmed as being growth-inhibitor producers (detection rate 0.29%). when tested against a wider spectrum of eight target organisms, some of the isol ...200419712399
impact of 4-chlorophenol contamination and/or inoculation with the 4-chlorophenol-degrading strain, arthrobacter chlorophenolicus a6l, on soil bacterial community structure.the 4-chlorophenol-degrading strain, arthrobacter chlorophenolicus a6l (chromosomally tagged with the firefly luciferase gene, luc) was inoculated into 4-chlorophenol-contaminated soil to assess the impact of bioaugmentation with a biodegrading strain on the indigenous microbiota. simultaneously, the impact of 4-chlorophenol alone, or inoculation with a. chlorophenolicus into non-contaminated soil, was addressed. using terminal restriction fragment length polymorphism (t-rflp) several significan ...200219709298
bacterial populations associated with mycelium of the arbuscular mycorrhizal fungus glomus intraradices.abstract the influences of the arbuscular mycorrhizal fungus glomus intraradices on the culturable aerobic-heterotrophic bacterial communities in the rhizosphere and hyphosphere of cucumber plants (cucumis satvius) were investigated. mycorrhizal and non-mycorrhizal plants were grown in compartmentalised growth units, each with a root compartment and two lateral root-free compartments. samples representing rhizosphere, root-free soil, root-free sand and washed sand extract were collected 52 days ...200219709247
plasmid localisation of atrazine-degrading genes in newly described chelatobacter and arthrobacter strains.abstract in a previous study, we isolated a collection of atrazine-degrading bacteria from various soils. the aim of this study was to localise the atrazine-degrading genes in these 25 atrazine-degrading strains. in the case of the gram-negative strains of chelatobacter heintzii, six to seven plasmids were observed. the atzabc and trzd genes were located on two or three plasmids with variable molecular masses. for the gram-positive strains of arthrobacter crystallopoietes, the atzbc genes were l ...200219709240
eric-pcr-based strain-specific detection of phenol-degrading bacteria in activated sludge of wastewater treatment evaluate the use of enterobacterial repetitive intergenic consensus pcr (eric-pcr)-derived probes and primers to specifically detect bacterial strains in an activated sludge microbial community.200919708883
genetic diversity of plant growth promoting rhizobacteria isolated from rhizospheric soil of wheat under saline this study, a total of 130 rhizobacteria was isolated from a saline infested zone of wheat rhizosphere, and screened for plant growth promoting (pgp) traits at higher salt (nacl) concentrations (2, 4, 6, and 8%). the results revealed that 24 rhizobacterial isolates were tolerant at 8% nacl. although all the 24 salt tolerable isolates produced indole-3-acetic acid (iaa), while 10 isolates solubilized phosphorus, eight produced siderophore, and six produced gibberellin. however, only three isol ...200919701667
the presence of embedded bacterial pure cultures in agar plates stimulate the culturability of soil bacteria.traditional methods for bacterial cultivation recover only a small fraction of bacteria from all sorts of natural environments, and attempts have been made to improve the bacterial culturability. here we describe the development of a cultivation method, based on the embedment of pure bacterial cultures in between two layers of agar. plates containing either embedded pseudomonas putida or arthrobacter globiformis resulted in higher numbers of cfus of soil bacteria (21% and 38%, respectively) afte ...200919699242
atrazine and terbuthylazine mineralization by an arthrobacter sp. isolated from a sugarcane-cultivated soil in kenya.a tropical soil from a kenyan sugarcane-cultivated field showed a very high capability to mineralize (14)c-ring-labeled atrazine. in laboratory experiments this soil mineralized about 90% of the applied atrazine within 98 d. the atrazine-degrading microbial community was enriched in liquid cultures containing atrazine as the sole n source and 100 mgl(-1) glucose as additional c source. from the enrichment culture a bacterial strain was isolated and identified by comparative sequence analysis of ...200919674769
effects of bacterial treatment at early stages of atlantic cod (gadus morhua l.) on larval survival and assess the effects of bacterial treatment at the earliest stages of cod rearing on the microbial load, larval development and performance, testing three bacterial strains (carnobacterium divergens v41, arthrobacter sp. and enterococcus sp.) in vivo that were previously shown to have inhibitory potential towards fish pathogens in vitro.201019664064
monitoring enzyme catalysis in the multimeric state: direct observation of arthrobacter 4-hydroxybenzoyl-coenzyme a thioesterase catalytic complexes using time-resolved electrospray ionization mass spectrometry.the ability to examine real-time reaction kinetics for multimeric enzymes in their native state may offer unique insights into understanding the catalytic mechanism and its interplay with three-dimensional structure. in this study, we have used a time-resolved electrospray mass spectrometry approach to probe the kinetic mechanism of 4-hydroxybenzoyl-coenzyme a (4-hba-coa) thioesterase from arthrobacter sp. strain su in the millisecond time domain. intact tetrameric complexes of 4-hba-coa thioest ...200919635449
a new cold-adapted beta-d-galactosidase from the antarctic arthrobacter sp. 32c - gene cloning, overexpression, purification and properties.the development of a new cold-active beta-d-galactosidases and microorganisms that efficiently ferment lactose is of high biotechnological interest, particularly for lactose removal in milk and dairy products at low temperatures and for cheese whey bioremediation processes with simultaneous bio-ethanol production.200919631003
arthrobacter psychrochitiniphilus sp. nov., a psychrotrophic bacterium isolated from antarctica.a psychrotrophic arthrobacter strain, gp3(t), was isolated from adélie penguin guano from antarctica and characterized. the 16s rrna gene sequence of the novel strain showed the highest similarity (97.8 %) with that of arthrobacter psychrolactophilus b7(t). the novel strain showed a morphological change from rod to coccus. the growth temperature range of strain gp3(t) was 0-25 degrees c, with optimal growth at 20 degrees c. the strain grew over a salinity range of between 0 and 3 % (w/v) nacl an ...200919625417
production of acrylic acid from acrylonitrile by immobilization of arthrobacter nitroguajacolicus zjutb06-99.immobilized cells of arthrobacter nitroguajacolicus zjutb06-99 capable of producing nitrilase was used for biotransformation of acrylonitrile to acrylic acid. six different entrapment matrixes were chosen to search for a suitable support in terms of nitrilase activity. ca-alginate proved to be more advantageous over other counterparts in improvement of the biocatalyst activity and bead mechanical strength. the effects of sodium alginate concentration, cacl2 concentration, bead diameter, and rati ...200919597316
selection of a cold-adapted bacterium for bioremediation of wastewater at low temperatures.amongst more than 1000 isolates collected in various cold environments, the strain arthrobacter psychrolactophilus sp 31.3 has been selected for its ability to grow and to produce exoenzymes at low temperatures, its inability to grow at 37 degrees c, its non-halophilic character and its growth versatility on various media. this non-pathogenic strain displays a strong resistance to desiccation and storage at room temperature and is suitable for the production of freeze-dried bacterial starters. w ...200919578929
azolla-anabaena's behaviour in urban wastewater and artificial media--influence of combined nitrogen.the results of using the nitrogen fixing symbiotic system azolla-anabaena to improve the quality of treated urban wastewater, particularly on what concerns phosphorus removal efficiencies (40-65%), obtained in continuous assays performed during the past few years and presented earlier, were very promising. nevertheless, the presence of combined nitrogen in some wastewaters can compromise the treatment efficiency. the main goal of this work was to compare plants behaviour in wastewater and in min ...200919559459
isolation and characterization of arthrobacter sp. hy2 capable of degrading a high concentration of p-nitrophenol.a soil bacterium strain, capable of using p-nitrophenol (pnp) as its sole source of carbon and energy, was isolated by enrichment on minimal salt medium (msm). on the basis of a phylogenetic analysis of 16s rrna gene sequences the bacterium is a species of arthrobacter, closely related to arthrobacter ureafaciens dsm 20126. this strain has an unusually high substrate tolerance for pnp degradation in msm. greatest degradation of pnp was observed at 30 degrees c and under slightly alkaline ph (ph ...200919540107
synthesis of 9-beta-d-arabinofuranosylguanine by combined use of two whole cell biocatalysts.unlike the preparation of other purine nucleosides, transglycosylation from a pyrimidine nucleoside and guanine is difficult because of the low solubility of this base. thus, another strategy, based on the coupled action of two whole cell biocatalyzed reactions, transglycosylation and deamination, was used. enterobacter gergoviae and arthrobacter oxydans were employed to synthesize 9-beta-d-arabinofuranosylguanine (arag), an efficient anti leukemic drug.200919523826
two alternative modes for optimizing nylon-6 byproduct hydrolytic activity from a carboxylesterase with a beta-lactamase fold: x-ray crystallographic analysis of directly evolved 6-aminohexanoate-dimer hydrolase.promiscuous 6-aminohexanoate-linear dimer (ald)-hydrolytic activity originally obtained in a carboxylesterase with a beta-lactamase fold was enhanced about 80-fold by directed evolution using error-prone pcr and dna shuffling. kinetic studies of the mutant enzyme (hyb-s4m94) demonstrated that the enzyme had acquired an increased affinity (k(m) = 15 mm) and turnover (k(cat) = 3.1 s(-1)) for ald, and that a catalytic center suitable for nylon-6 byproduct hydrolysis had been generated. construction ...200919521995
optimization of physical parameters for lipase production from arthrobacter sp. bgcc#490.the physical parameters for the production of thermostable, alkaline lipase from arthrobacter sp. bgcc# 490 were optimized using response surface methodology (rsm), employing face centered central composite design (fcccd). the design was employed by selecting ph, temperature and incubation period as the model factors and to achieve maximum yield, interaction of these factors was studied by rsm. a second-order quadratic model and response surface method showed that the optimum conditions for lipa ...200919517996
glycinebetaine-induced water-stress tolerance in coda-expressing transgenic indica rice is associated with up-regulation of several stress responsive genes.rice (oryza sativa l.), a non-accumulator of glycinebetaine (gb), is highly susceptible to abiotic stress. transgenic rice with chloroplast-targeted choline oxidase encoded by the coda gene from arthrobacter globiformis has been evaluated for inheritance of transgene up to r5 generation and water-stress tolerance. during seedling, vegetative and reproductive stages, transgenic plants could maintain higher activity of photosystem ii and they show better physiological performance, for example, enh ...200919490479
batch and continuous biosorption of cu(2+) by immobilized biomass of arthrobacter sp.the ability of free and polysulphone immobilized biomass of arthrobacter sp. to remove cu(2+) ions from aqueous solution was studied in batch and continuous systems. the langmuir and freundlich isotherm models were applied to the data. the langmuir isotherm model was found to fit the sorption data indicating that sorption was monolayer and uptake capacity (q(o)) was 175.87 and 158.7mg/g for free and immobilized biomass respectively at ph 5.0 and 30 degrees c temperature, which was also confirmed ...200919487070
bacterial diversity of soil samples from the western himalayas, india.high-altitude cold habitats of the himalayas are little explored with respect to bacterial diversity. diverse bacterial species and phylotypes obtained by culture-dependent and culture-independent approaches are reported here. phylogenetic analysis and modulation of bacterial diversity with altitude and available organic carbon content are also described. psychrophilic and psychrotolerant bacteria dominated the himalayan habitats, accounting for 60% of the cultivated strains. isolates produced o ...200919483785
identification of a novel self-sufficient styrene monooxygenase from rhodococcus opacus 1cp.sequence analysis of a 9-kb genomic fragment of the actinobacterium rhodococcus opacus 1cp led to identification of an open reading frame encoding a novel fusion protein, stya2b, with a putative function in styrene metabolism via styrene oxide and phenylacetic acid. gene cluster analysis indicated that the highly related fusion proteins of nocardia farcinica ifm10152 and arthrobacter aurescens tc1 are involved in a similar physiological process. whereas 413 amino acids of the n terminus of stya2 ...200919482928
microbial responses to mustard gas dumped in the baltic sea.microbiological studies were carried out on chemical weapon dump sites in the baltic sea. the effect of mustard gas hydrolysis products (mghps) on marine microbiota and the ability of microorganisms to degrade mghps were studied. many stations at the dump sites demonstrated reduced microbial diversity, and increased growth of species able to use mustard gas hydrolysis products as sole source of carbon. significant amounts of mghp-degrading bacteria were revealed in the near-bottom water. the mgh ...200919481794
microbial ecology of gorgonzola rinds and occurrence of different biotypes of listeria this study we investigated the microbiota of gorgonzola rinds and maturing shelf swabs collected in 5 different maturing cellars in the northwest part of italy, in association with the detection and characterization of listeria monocytogenes. culture-dependent and -independent methods were performed in order to profile the main microbial populations present on the rinds and in the maturing shelves and species-specific pcr and pulsed field gel electrophoresis (pfge) were used to identify and t ...200919477544
molecular design of a nylon-6 byproduct-degrading enzyme from a carboxylesterase with a beta-lactamase fold.a carboxylesterase with a beta-lactamase fold from arthrobacter possesses a low level of hydrolytic activity (0.023 mumol.min(-1).mg(-1)) when acting on a 6-aminohexanoate linear dimer byproduct of the nylon-6 industry (ald). g181d/h266n/d370y triple mutations in the parental esterase increased the ald-hydrolytic activity 160-fold. kinetic studies showed that the triple mutant possesses higher affinity for the substrate ald (k(m) = 2.0 mm) than the wild-type ald hydrolase from arthrobacter (k(m) ...200919476493
[effect of a novel fibrinolytic enzyme fa-i on thrombosis and thrombolysis].to study the effect of fa-i, a novel fibrinolytic enzyme isolated from the metabolite of arthrobacter sp. dr-536, on thrombosis and thrombolysis in vivo.200919462909
viability and potential for immigration of airborne bacteria from africa that reach high mountain lakes in europe.we have analysed the diversity of the bacteria, which grow after addition of concentrated airborne particles and desert dust in different microcosms combinations with water samples from oligotrophic alpine lakes. we used, on the one hand, airborne bacteria transported by an african dust plume and collected in a high mountain area in the central pyrenees (spain). on the other hand, we collected desert dust in mauritania (c. 3000 km distance, and a few days estimated airborne journey), a known sou ...200919453609
[effect of elevation of 1-hydroxy-2-naphthoic acid concentration on the lag phase of arthrobacter sp. k3: kinetic analysis]. 200919449734
membrane bioreactor treatment of a simulated metalworking fluid wastewater containing ethylenediaminetetraacetic acid and dicyclohexylamine.membrane bioreactors (mbrs) have been installed at automotive plants to treat metalworking fluid (mwf) wastewaters, which are known to contain toxic and/or recalcitrant organic compounds. a laboratory study was conducted to evaluate treatment of a simulated wastewater prepared from a semisynthetic mwf, which contains two such compounds, dicyclohexylamine (dcha) and ethylenediaminetetraacetic acid (edta). primary findings were as follows: during stable operating periods, almost all chemical oxyge ...200919445324
uptake of l-nicotine and of 6-hydroxy-l-nicotine by arthrobacter nicotinovorans and by escherichia coli is mediated by facilitated diffusion and not by passive diffusion or active transport.the mechanism by which l-nicotine is taken up by bacteria that are able to grow on it is unknown. nicotine degradation by arthrobacter nicotinovorans, a gram-positive soil bacterium, is linked to the presence of the catabolic megaplasmid pao1. l-[(14)c]nicotine uptake assays with a. nicotinovorans showed transport of nicotine across the cell membrane to be energy-independent and saturable with a k(m) of 6.2+/-0.1 microm and a v(max) of 0.70+/-0.08 micromol min(-1) (mg protein)(-1). this is in ac ...200919443550
ecotoxicological characterisation of 12 incineration ashes using 6 laboratory the european waste list (2000/532/ec as amended) the ash of municipal waste incineration is defined as a so called mirror entry. this waste can be classified as hazardous or non-hazardous depending on the content of hazardous substances and other risk properties. for the assignment of waste in mirror entries, 14 criteria are defined. one of the criteria is h14 "ecotoxic". in the presented study, the ecotoxicological potential of 12 ashes from different incineration plants has been assessed us ...200919442505
improvement of catalytic properties of lipase from arthrobacter sp. by encapsulation in hydrophobic sol-gel this work, lipase from arthrobacter sp. was immobilized by sol-gel encapsulation to improve its catalytic properties. various silanizing agents including vinyl-trimethoxy silane, octyl-trimethoxy silane, gamma-(methacryloxypropyl)-trimethoxy silane (maptms) and tetraethoxysilane (teos) were chosen as the precursors. among them, maptms was for the first time utilized to encapsulate lipases, and the prepared enzyme by copolymerization of maptms and teos exhibited the highest activity in both th ...200919428242
effects of proteus vulgaris growth on the establishment of a cheese microbial community and on the production of volatile aroma compounds in a model investigate the impact of proteus vulgaris growth on a multispecies ecosystem and on volatile aroma compound production during cheese ripening.200919426267
high yield synthesis of 12-aminolauric acid by "enzymatic transcrystallization" of omega-laurolactam using omega-laurolactam hydrolase from acidovorax sp. t31.the genes encoding omega-laurolactam hydrolases from cupriavidus sp. t7, acidovorax sp. t31, cupriavidus sp. u124, and sphingomonas sp. u238 were cloned and sequenced. nucleotide and amino acid sequence analysis of the four genes indicated that the primary structures of these omega-laurolactam hydrolases are significantly similar to the 6-aminohexanoate-cyclic-dimer hydrolase (ec these genes were expressed in escherichia coli, and the omega-laurolactam hydrolysing activity of the reco ...200919420719
biodegradation of phenanthrene and pyrene in compost-amended soil.this study investigated the biodegradation of the polycyclic aromatic hydrocarbons (pahs) phenanthrene and pyrene in compost and compost-amended soil. the degradation rates of the two pahs were phenanthrene>pyrene. the degradation of pah was enhanced when the two pahs were present simultaneously in the soil. the addition of either of the two types of compost (straw and animal manure) individually enhanced pah degradation. compost samples were separated into fractions with various particle size r ...200919412845
contribution of flavin covalent linkage with histidine 99 to the reaction catalyzed by choline oxidase.the fad-dependent choline oxidase has a flavin cofactor covalently attached to the protein via histidine 99 through an 8alpha-n(3)-histidyl linkage. the enzyme catalyzes the four-electron oxidation of choline to glycine betaine, forming betaine aldehyde as an enzyme-bound intermediate. the variant form of choline oxidase in which the histidine residue has been replaced with asparagine was used to investigate the contribution of the 8alpha-n(3)-histidyl linkage of fad to the protein toward the re ...200919398559
effect of immobilization of a bacterial consortium on diuron dissipation and community dynamics.this work intended to study the relationship between diuron herbicide dissipation and the population dynamics of co-cultivated delftia acidovorans wdl34 (wdl34) and arthrobacter sp. n4 (n4) for different cell formulations: free cells or immobilization in ca-alginate beads of one or both strains. gfp-tagged wdl34 and n4 gram staining allowed analyzing the cell growth and distribution of each strain in both beads and culture medium in the course of the time. compared to the free cell co-culture of ...200919386487
a novel nicotine catabolic plasmid pmh1 in pseudomonas sp. strain hf-1.attempts were made to acquire a plasmid-loss mutant via various methods (spontaneous mutation, sds, and mitomycin c), among which the method involving mitomycin c (10 microg/ml) has been proven successful. concomitant with the loss of the plasmid in pseudomonas sp. strain hf-1, the cured derivative was identified as having a nicotine-negative (nic-) phenotype, named mutant strain 6-13 (nic-). after plasmids were transferred from strain hf-1 (named plasmid pmh1) to the mutant strain 6-13, the mut ...200919370065
enzymatic glycosylation of triazole-linked glcnac/glc-peptides: synthesis, stability and anti-hiv activity of triazole-linked hiv-1 gp41 glycopeptide c34 analogues.long-lasting sweet proteins: the chemoenzymatic synthesis of a triazole (t)-linked glycosylated c34 fragment from hiv-1 gp41 is described. the glycopeptide shows high solubility, excellent fusion inhibition, and as shown in the graph, promising protease resistance. endoglycosidase-catalyzed transglycosylation of triazole-linked glucose (glc) and n-acetylglucosamine (glcnac)-containing dipeptides and polypeptides was achieved by using synthetic sugar oxazoline as the donor substrate. it was found ...200919353609
arthrobacter halodurans sp. nov., a new halotolerant bacterium isolated from sea water.a novel gram-positive, halotolerant, non-sporulating, non-motile, catalase-positive, oxidase-negative and aerobic bacterium, designated strain jsm 078085(t), was isolated from sea water collected from the south china sea. strain jsm 078085(t) exhibited a rod-coccus growth cycle and produced a yellow pigment. the strain was able to grow in the presence of 0-12% (w/v) nacl and at ph 6.0-9.5 and 4-35 degrees c; optimum growth was observed at ph 7.0 and 25-30 degrees c in the absence of nacl. the pe ...200919337850
four novel arthrobacter species isolated from filtration substrate.four gram-positive, non-motile, non-spore-forming bacterial strains, lc4(t), lc6(t), lc10(t) and lc13(t), were isolated from a filtration substrate made from trass, a volcanic rock, and their taxonomic positions were investigated by a polyphasic taxonomic approach. the novel strains grew over a temperature range of 5-40 degrees c, at ph values of 6-11 and in the presence of 3-7 % (w/v) nacl. a phylogenetic tree based on 16s rrna gene sequences showed the novel strains formed a distinct evolution ...200919329620
the x-ray crystal structure of an arthrobacter protophormiae endo-beta-n-acetylglucosaminidase reveals a (beta/alpha)(8) catalytic domain, two ancillary domains and active site residues key for transglycosylation activity.glycoside hydrolase family gh85 is a family of endo-beta-n-acetylglucosaminidases that is responsible for the hydrolysis of beta-1,4 linkage in the n,n-diacetylchitobiose core of n-linked glycans. the endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) is of particular interest, given its increasing use for the chemoenzymatic synthesis of bespoke n-glycans using n-glycan oxazolines as glycosyl donors. the e173q variant of endo-a is especially attractive for synthesis, as i ...200919327363
genetic and phenotypic diversity of fenitrothion-degrading bacteria isolated from soils.twenty-seven fenitrothion-degrading bacteria were isolated from different soils, and their genetic and phenotypic characteristics were investigated. analysis of the 16s rdna sequence showed that the isolates were related to members of the genera burkholderia, pseudomonas, sphingomonas, cupriavidus, corynebacterium, and arthrobacter. among the 27 isolates, 12 different chromosomal dna fingerprinting patterns were obtained by polymerase chain reaction (pcr) amplification of repetitive extragenic p ...200919307758
construction, expression and characterization of fusion enzyme from arthrobacter oxydans dextranase and klebsiella pneumoniae artificial fusion protein of arthrobacter oxydans dextranase and klebsiella pneumoniae alpha-amylase was constructed and expressed in escherichia coli. most of the expressed protein existed as an insoluble fraction, which was solubilized with urea. the purified fusion enzyme electrophoretically migrated as a single protein band; m = 137 kda, and exhibited activities of both dextranase (10.8 u mg(-1)) and amylase (7.1 u mg(-1)), which were lower than that of reference dextranase (13.3 u mg(-1) ...200919305953
high rate of n2 fixation by east siberian cryophilic soil bacteria as determined by measuring acetylene reduction in nitrogen-poor medium solidified with gellan gum.for evaluating n(2) fixation of diazotrophic bacteria, nitrogen-poor liquid media supplemented with at least 0.5% sugar and 0.2% agar are widely used for acetylene reduction assays. in such a soft gel medium, however, many n(2)-fixing soil bacteria generally show only trace acetylene reduction activity. here, we report that use of a n(2) fixation medium solidified with gellan gum instead of agar promoted growth of some gellan-preferring soil bacteria. in a soft gel medium solidified with 0.3% ge ...200919286791
meloidogyne incognita infested soil amended with chicken litter.the effects of chicken litter on meloidogyne incognita in cotton, gossypium hirsutum cv. dpl50 were determined in field microplots. litters (manure and pine-shaving bedding) from a research facility and a commercial broiler house were used. treatments consisted of 0.25%, 0.5%, and 1% litter by dry weight of soil for each kind of litter. three control treatments consisted of soil not amended with litter, with and without nematodes, and one treatment to which mineral fertilizer was added at a nitr ...199619277155
evaluation of biocontrol activity of rhizobacteria from beta vulgaris against heterodera hundred fifty rhizobacteria isolated from roots of swiss chard grown in a soil suppressive to the sugar beet cyst nematode, heterodera schachtii, were tested for their influence on the nematode's ability to hatch and infect roots. two screening systems were used that focused on the ability of bacteria to inhibit either nematode hatching or root infection. most of the bacterial strains reduced hatching in vitro compared to the control, while with 5% of the strains there were 0% hatch. seven p ...199919270875
industrial production of difructose anhydride iii (dfa iii) from crude inulin extracted from chicory roots using arthrobacter sp. h65-7 fructosyltransferase.a practical, economical, and industrial process for the enzymatic production of difructose anhydride iii (dfa iii) was investigated for crude inulin prepared from chicory roots using arthrobacter sp. h65-7 fructosyltransferase. a comparable level of dfa iii production to that from commercial inulin was obtained using crude inulin, suggesting the feasibility of this production process.200919269589
tylenchulus semipenetrans alters the microbial community in the citrus rhizosphere.infection of citrus seedlings by tylenchulus semipenetrans was shown to reduce subsequent infection of roots by phytophthora nicotianae and to increase plant growth compared to plants infected by only the fungus. hypothetical mechanisms by which the nematode suppresses fungal development include nutrient competition, direct antibiosis, or alteration of the microbial community in the rhizosphere to favor microorganisms antagonistic to p. nicotianae. a test of the last hypothesis was conducted via ...200319265991
structural basis and catalytic mechanism for the dual functional endo-beta-n-acetylglucosaminidase a.endo-beta-n-acetylglucosaminidases (engases) are dual specificity enzymes with an ability to catalyze hydrolysis and transglycosylation reactions. recently, these enzymes have become the focus of intense research because of their potential for synthesis of glycopeptides. we have determined the 3d structures of an engase from arthrobacter protophormiae (endo-a) in 3 forms, one in native form, one in complex with man(3)glcnac-thiazoline and another in complex with glcnac-asn. the carbohydrate moie ...200919252736
actinobacterial community dynamics in long term managed grasslands.palace leas, a long-term experiment at cockle park farm, northumberland, uk was established in winter 1896-1897 since when the 13 plots have received regular and virtually unchanged mineral fertiliser and farm yard manure inputs. fertilisers have had a profound impact on soil ph with the organically fertilised plots showing a significantly higher ph than those receiving mineral fertiliser where ammonium sulphate has led to soil acidification. here, we investigate the impact of organic and minera ...200919247797
the oligomeric assembly of the novel haem-degrading protein hbps is essential for interaction with its cognate two-component sensor kinase.hbps, a novel protein of previously unknown function from streptomyces reticuli, is up-regulated in response to haemin- and peroxide-based oxidative stress and interacts with the sens/senr two-component signal transduction system. in this study, we report the high-resolution crystal structures (2.2 and 1.6 a) of octomeric hbps crystallized in the presence and in the absence of haem and demonstrate that iron binds to surface-exposed lysine residues of an octomeric assembly. based on an analysis o ...200919244623
bacterial communities of tyre monofill sites: growth on tyre shreds and investigate bacterial communities of tyre monofill sites, colonization of tyre material by bacteria and the effect of tyre leachate on bacteria.200919239530
global proteomic analysis of the chromate response in arthrobacter sp. strain fb24.a global proteomic evaluation of the response of arthrobacter sp. strain fb24 to 5 and 20 mm cr(vi) was conducted using both two-dimensional gel electrophoresis (2-dge) and liquid chromatography coupled with tandem mass spectrometry (lc/lc-ms/ms). the changes in protein expression found with 2-dge indicate alterations in central metabolism and amino acid synthesis. proteome coverage increased from 22% with 2-dge to 71% with lc/lc-ms/ms. the proteins exhibiting the highest levels of expression un ...200919231868
thermal analysis of whole bacterial cells exposed to potassium permanganate using differential scanning calorimetry: a biphasic dose-dependent response to stress.the dsc technique applied to the study of the toxic impact of permanganate on bacterial cell culture detected the lack of linearity in the dose-response effect. the results were confirmed by the traditional assay of colony forming ability. the changed pattern of thermal spectra of a. oxydans at permanganate treatment, the measurement of the total heat capacity and the temperature of dnp complex demonstrate the possibility to verify the toxic impact in dependence of concentrations value.200919219375
purification and characterization of arsenite oxidase from arthrobacter sp.the chemolithoautotroph, arthrobacter sp.15b oxidizes arsenite to arsenate using a membrane bound arsenite oxidase. the enzyme arsenite oxidase is purified to its homogeneity and identified using maldi-tof ms analysis. upon further characterization, it was observed that the enzyme is a heterodimer showing native molecular mass as approximately 100 kda and appeared as two subunits of approximately 85 kda lsu and 14 kda ssu on sds-page. the v(max) and k(m) values of the enzyme was found to be 2.45 ...200919214757
glycosynthases enable a highly efficient chemoenzymatic synthesis of n-glycoproteins carrying intact natural n-glycans.homogeneous n-glycoproteins carrying defined natural n-glycans are essential for detailed structural and functional studies. the transglycosylation activity of the endo-beta-n-acetylglucosaminidases from arthrobacter protophormiae (endo-a) and mucor hiemalis (endo-m) holds great potential for glycoprotein synthesis, but the wild-type enzymes are not practical for making glycoproteins carrying native n-glycans because of their predominant activity for product hydrolysis. in this article, we repor ...200919199609
arthrobacter phenanthrenivorans sp. nov., to accommodate the phenanthrene-degrading bacterium arthrobacter sp. strain sphe3.a novel phenanthrene-degrading bacterium, designated strain sphe3(t), was isolated from a creosote-contaminated soil in greece. cells were non-motile, gram-positive, aerobic, and rod- to coccus-shaped. the strain was isolated on the basis of formation of a clear zone on agar plates sprayed with phenanthrene. optimal growth occurred at 30 degrees c. the g+c content of the dna was 65.7 mol%. the polar lipid pattern of strain sphe3(t) consisted of phosphatidylethanolamine, phosphatidylglycerol and ...200919196765
proposal of sinomonas flava gen. nov., sp. nov., and description of sinomonas atrocyanea comb. nov. to accommodate arthrobacter atrocyaneus.a novel actinomycete strain, designated cw 108(t), was isolated from a forest soil in anhui province, china. the cells were strictly aerobic, non-motile, bent rods. the strain grew optimally at 30-37 degrees c and ph 6.0-8.0. chemotaxonomically, the peptidoglycan type was a3alpha, the cell-wall sugars contained galactose, mannose and ribose, the polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylmonomethylethanolamine, the major fatty acids were ...200919196763
endo-beta-n-acetylglucosaminidase-catalyzed polymerization of beta-glcp-(1-->4)-glcpnac oxazoline: a revisit to enzymatic alternative synthesis of beta-glcp-(1-->4)-glcpnac oxazoline is described, and its enzymatic reaction with the endo-beta-n-acetylglucosaminidase from arthrobacter protophormiae (endo-a) was re-investigated. under normal transglycosylation conditions with a catalytic amount of enzyme, endo-a showed only marginal activity for transglycosylation with the disaccharide oxazoline, consistent with our previous observations. however, when used in a relatively large quantity, endo-a could promote the ...200919193364
preferential hydrolysis of aberrant intermediates by the type ii thioesterase in escherichia coli nonribosomal enterobactin synthesis: substrate specificities and mutagenic studies on the active-site residues.the type ii thioesterase enth is a hotdog fold protein required for optimal nonribosomal biosynthesis of enterobactin in escherichia coli. its proposed proofreading activity in the biosynthesis is confirmed by its efficient restoration of enterobactin synthesis blocked in vitro by analogs of the cognate precursor 2,3-dihydroxybenzoate. steady-state kinetic studies show that enth recognizes the phosphopantetheine group and the pattern of hydroxylation in the aryl moiety of its thioester substrate ...200919193103
improvement of steroid biotransformation with hydroxypropyl-beta-cyclodextrin induced complexation.the inclusion complexes induced by cyclodextrins and its derivates have been shown previously to enhance the biotransformation of hydrophobic compounds. using hydroxypropyl-beta-cyclodextrin (hp-beta-cd; 20% w/v), the water solubility of cortisone acetate increased from 0.039 to 7.382 g l(-1) at 32 degrees c. the solubilization effect of hp-beta-cd was far superior to dimethylformamide (dmf) and ethanol. the dissolution rate also significantly increased in the presence of hp-beta-cd. the enzymat ...200919189059
targeting prokaryotic choline oxidase into chloroplasts enhance the potential of photosynthetic machinery of plants to withstand oxidative damage.chloroplasts from plants of transgenic lines expressing prokaryotic choline oxidase gene (the coda(ps) gene; genbank accession number-ay589052) and wild-type of chickpea and indian mustard were evaluated for their efficacy to withstand photoinhibitory damage, by exposing them to high light intensity ( approximately 1200micromolm(-2)s(-1) photon flux density) at 10 and 25 degrees c. western analysis confirmed presence of choline oxidase in chloroplasts of only transgenic lines. the loss in ps ii ...200919186067
gene cloning, expression, and characterization of a novel trehalose synthase from arthrobacter aurescens.trehalose synthase (tres) is an intramolecular transglycosylase. it specially catalyzes the conversion of maltose and trehalose. in this study, a novel tres gene, which had a length of 1,797 bp and encoded 598 amino acids, was cloned from arthrobacter aurescens cgmcc 1.1892 and expressed in escherichia coli. thin layer chromatography results indicated that it could catalyze the conversion between maltose and trehalose in one step. however, the ion chromatography results showed that, as a byprodu ...200919172263
mating triggers dynamic immune regulations in wood ant queens.mating can affect female immunity in multiple ways. on the one hand, the immune system may be activated by pathogens transmitted during mating, sperm and seminal proteins, or wounds inflicted by males. on the other hand, immune defences may also be down-regulated to reallocate resources to reproduction. ants are interesting models to study post-mating immune regulation because queens mate early in life, store sperm for many years, and use it until their death many years later, while males typica ...200919170815
c29 olefinic hydrocarbons biosynthesized by arthrobacter species.arthrobacter aurescens tc1, arthrobacter chlorophenolicus a6, arthrobacter crystallopoietes, and arthrobacter oxydans produce long-chain monoalkenes, predominantly cis-3,25-dimethyl-13-heptacosene. four other arthrobacter strains did not form alkenes. the level of cis-3,25-dimethyl-13-heptacosene in arthrobacter chlorophenolicus a6 remained proportional to cell mass during growth. cis-3,25-dimethyl-13-heptacosene did not support growth of a. chlorophenolicus a6.200919168653
hexavalent chromium reduction by free and immobilized cell-free extract of arthrobacter the present study, hexavalent chromium (cr(vi)) reduction potential of chromium reductase associated with the cell-free extracts (cfe) of arthrobacter rhombi-re species was evaluated. arthrobacter rhombi-re, an efficient cr(vi) reducing bacterium, was enriched and isolated from a chromium-contaminated site. chromium reductase activity of arthrobacter rhombi-re strain was associated with the cell-free extract and the contribution of extracellular enzymes to cr(vi) reduction was negligible. nad ...201019165627
assessing the importance of dietborne cadmium and particle characteristics on bioavailability and bioaccumulation in the nematode caenorhabditis investigate the impact of multiple cadmium exposure pathways on bioavailability and bioaccumulation, caenorhabditis elegans were exposed to either dissolved cadmium or to both particulate (dietborne) and dissolved cadmium. the dietborne metal exposure scenarios included evaluations of two bacteria species (escherichia coli and arthrobacter globiformis), varying bacteria concentrations, artificial particles (with different surface functional groups or coated with lipopolysaccharides), as well ...200919159127
biodegradation of mixed phenolic compounds under high salt conditions and salinity fluctuations by arthrobacter sp. w1.high salt concentration and salinity fluctuations in wastewater challenge the efficiency of microbial strains used for cleanup of pollutants. in this study, it was investigated that the new isolated arthrobacter sp. w1 degraded mixed phenolic compounds under complex salt conditions. the results showed that arthrobacter sp. w1 was able to utilize various phenolic compounds as carbon source under high salt conditions. it can degrade phenol and p-cresol mixture at 10% nacl, although rates of degrad ...200919156367
isolation and characterization of atrazine-degrading arthrobacter sp. ad26 and use of this strain in bioremediation of contaminated soil.a bacterial strain (ad26) capable of utilizing atrazine as a sole nitrogen source for growth was isolated from an industrial wastewater sample by enrichment culture. the 16s rrna gene sequencing identified ad26 as an arthrobacter sp. pcr assays indicated that ad26 contained atrazine-degrading genes trzn and atzbc. the trzn gene of ad26 only differs from the trzn of arthrobacter aurescens tc1 by one base (a-->t at 907) and one amino acid (met-->leu at 303). the specific activity of trzn of ad26 i ...200819143347
crystallographic, spectroscopic, and computational analysis of a flavin c4a-oxygen adduct in choline oxidase.flavin c4a-oo(h) and c4a-oh adducts are critical intermediates proposed in many flavoenzyme reaction mechanisms, but they are rarely detected even by rapid transient kinetics methods. we observe a trapped flavin c4a-oh or c4a-oo(h) adduct by single-crystal spectroscopic methods and in the 1.86 a resolution x-ray crystal structure of choline oxidase. the microspectrophotometry results show that the adduct forms rapidly in situ at 100 k upon exposure to x-rays. density functional theory calculatio ...200919133805
genes involved in arsenic transformation and resistance associated with different levels of arsenic-contaminated soils.arsenic is known as a toxic metalloid, which primarily exists in inorganic form [as(iii) and as(v)] and can be transformed by microbial redox processes in the natural environment. as(iii) is much more toxic and mobile than as(v), hence microbial arsenic redox transformation has a major impact on arsenic toxicity and mobility which can greatly influence the human health. our main purpose was to investigate the distribution and diversity of microbial arsenite-resistant species in three different a ...200919128515
isolation and characterization of mesotrione-degrading bacillus sp. from soil.dissipation kinetics of mesotrione, a new triketone herbicide, sprayed on soil from limagne (puy-de-dôme, france) showed that the soil microflora were able to biotransform it. bacteria from this soil were cultured in mineral salt solution supplemented with mesotrione as sole source of carbon for the isolation of mesotrione-degrading bacteria. the bacterial community structure of the enrichment cultures was analyzed by temporal temperature gradient gel electrophoresis (ttge). the ttge fingerprint ...200919121884
arthrobacter sp. lipase immobilization for preparation of enantiopure masked beta-amino alcohols.recent reports on immobilization of lipase from arthrobacter sp. (abl, mtcc 5125; iiim isolate) on insoluble polymers have shown altered properties including stability and enantioselectivity. present work demonstrates a facile method for the preparation of enantiopure beta-amino alcohols by modulation of abl enzyme properties via immobilization on insoluble as well as soluble supports using entrapment/covalent binding techniques. efficacies of immobilized abl on insoluble supports prepared from ...200919081255
decomposition of cr(v)-diols to cr(iii) complexes by arthrobacter oxydans.we demonstrated previously that cr(vi) is readily reduced to oxocr(v)-diols at the surface of arthrobacter oxydans-a gram-positive aerobic bacteria isolated from columbia basalt rocks originated from a highly contaminated site in the usa. here, we report an electron spin resonance (esr) study of cr(iii) hydroxide formation from cr(v)-diols by this bacterial strain as cells were exposed to 35, 200, and 400 mg/l of cr(vi) under aerobic conditions as a batch culture and as lyophilized cells. the ti ...200919067030
preliminary study of a microbeads based histamine detection for food analysis using thermostable recombinant histamine oxidase from arthrobacter crystallopoietes kait-b-007.we designed and prepared a micro biosensing system consisting of a flow through system with a sub-micro liter injection valve and a sub-micro liter volume bioreactor. an electrochemical detector was combined with the reactor for immediate detections. the volumes of the reactor and the sample loop for the injection were 850 nl and 320 nl, respectively. this paper described about the characteristics of the sensing system in the case of histamine detection for food analysis. histamine oxidase from ...200919064110
structural characterization and antithrombin activity of dermatan sulfate purified from marine clam scapharca inaequivalvis.glycosaminoglycans from the body of marine clam scapharca inaequivalvis were extracted at about 0.15- 0.18 mg/g of dry tissue, composed of dermatan sulfate (ds) (approx. 74%) and heparan sulfate (26%). after treatment with nitrous acid, ds was isolated for further complete structural characterization. agarose-gel electrophoresis in combination with various enzymes, chondroitin abc lyase, chondroitin b lyase, chondroitin acii lyase from arthrobacter aurescens, and chondroitin ac lyase from flavob ...200919056786
maturing dynamics of surface microflora in fontina pdo cheese studied by culture-dependent and -independent study the evolution of rind microbial communities in fontina pdo cheese.200919054234
arthrobacter oxydans as a biocatalyst for purine deamination.deaminases are enzymes that catalyze the hydrolysis of amino groups of nucleosides or their bases. because these enzymes play important roles in nucleotide metabolism, they are relevant targets in anticancer and antibacterial therapies. mammalian deaminases are commercially available but the use of bacterial whole cells, especially as biocatalysts, is continuously growing because of their economical benefits. moreover, deaminases are useful for the preparative chemoenzymatic transformation of nu ...200819054089
substitution of an active site valine uncovers a kinetically slow equilibrium between competent and incompetent forms of choline oxidase.the enzymatic oxidation of choline to glycine betaine is of interest because organisms accumulate glycine betaine intracellularly in response to stress conditions. this is relevant for the genetic engineering of crops with economic interest that do not naturally possess efficient pathways for the synthesis of glycine betaine and for the potential development of drugs that target the glycine betaine biosynthetic pathway in human pathogens. to date, the best characterized choline-oxidizing enzyme ...200819053262
hydride transfer made easy in the reaction of alcohol oxidation catalyzed by flavin-dependent oxidases.choline oxidase (e.c.; choline-oxygen 1-oxidoreductase) catalyzes the two-step, four-electron oxidation of choline to glycine betaine with betaine aldehyde as enzyme-associated intermediate and molecular oxygen as final electron acceptor. biochemical, structural, and mechanistic studies on the wild-type and a number of mutant forms of choline oxidase from arthrobacter globiformis have recently been carried out, allowing for the delineation at molecular and atomic levels of the mechanism ...200819053234
kinetics and spectroscopic evidence that the cu(i)-semiquinone intermediate reduces molecular oxygen in the oxidative half-reaction of arthrobacter globiformis amine oxidase.the role of copper during the reoxidation of substrate-reduced amine oxidases by o(2) has not yet been definitively established. both outer-sphere and inner-sphere pathways for the reduction of o(2) to h(2)o(2) have been proposed. a key step in the inner-sphere mechanism is the reaction of o(2) directly with the cu(i) center of a cu(i)-semiquinone intermediate. to thoroughly examine this possibility, we have measured the spectral changes associated with single-turnover reoxidation by o(2) of sub ...200819053231
safety assessment of bacterial choline oxidase protein introduced in transgenic crops for tolerance against abiotic stress.genetically modified crops have resistance to abiotic stress by introduction of choline oxidase protein. in the present study, the safety of choline oxidase protein derived from arthrobacter globiformis was assessed for toxicity and allergenicity. the protein was stable at 90 degrees c for 1 h. toxicity studies of choline oxidase in mice showed no significant difference (p > 0.05) from control in terms of growth, body weight, food consumption, and blood biochemical indices. histology of gut tiss ...200819035641
escravos light crude oil degrading potentials of axenic and mixed bacterial cultures.we assessed the relationship between growth profile and the extent of biodegradation of escravos light crude oil by axenic and mixed bacteria cultures in a shake flask. eleven petroleum-degrading bacteria were isolated by enrichment from oil-contaminated soils including, pseudomonas effusa, pseudomonas fluorescens, pseudomonas cruciviae, arthrobacter tumescens, pseudomonas species, pseudomonas tralucida, alcaligenes metacaligenes, micrococcus colpogenes, bacillus badius, nocardia paraffinae and ...200819029769
aerobic reduction of perchlorate by bacteria isolated in kerala, south india.possibility of perchlorate reduction by microbes raises hope for an eco-friendly mode of degradation of this toxic rocket fuel. this study reports 3 isolates (a1, a2 and a3) capable of molybdenum-independent degradation of perchlorate under aerobic conditions. the rate of degradation was the highest when perchlorate concentration was 17 mm, and then 3.2 mm, 4.7 mm and 4.1 mm of perchlorate was reduced by isolates a1, a2 and a3 (respectively) after 72 h at 28 degrees c under aerobic conditions. p ...200819029691
endophytic bacterial flora in root and stem tissues of black pepper (piper nigrum l.) genotype: isolation, identification and evaluation against phytophthora isolate and identify black pepper (piper nigrum l) associated endophytic bacteria antagonistic to phytophthora capsici causing foot rot disease.200919018963
liquid chromatography-mass spectrometry to study chondroitin lyase action pattern.liquid chromatography-mass spectrometry was applied to determine the action pattern of different chondroitin lyases. two commercial enzymes, chondroitinase abc (proteus vulgaris) and chondroitinase acii (arthrobacter aurescens), having action patterns previously determined by viscosimetry and gel electrophoresis were first examined. next, the action patterns of recombinant lyases, chondroitinase abc from bacteroides thetaiotaomicron (expressed in escherichia coli) and chondroitinase ac from flav ...200918992215
metabolic cooperation of gordonia sp. strain mtcc 4818 and arthrobacter sp. strain wy in the utilization of butyl benzyl phthalate: effect of a novel co-culture in the degradation of a mixture of phthalates.degradation of butyl benzyl phthalate (bbp) by a co-culture of gordonia sp. strain mtcc 4818 and arthrobacter sp. strain wy was investigated. in the degradation of bbp by the co-culture, the limitations of the individual species in metabolizing bbp were overcome, leading to the development of a consortium capable of complete utilization of this ester. in the degradation of bbp by the co-culture, the presence of multiple esterases was demonstrated in both species by activity staining of non-denat ...200818957587
[methodological aspects of assessing chitin utilization by soil microorganisms].a computational method for estimating specific activity of chitin decomposition by microorganisms is proposed. spectrophotometric and gas chromatographic methods have been used to determine the rates of chitinase production, biomass accumulation, and carbon dioxide emission by pure cultures of microorganisms grown on a chitin-containing medium. among dominants of the chitinolytic community of chernozem (trichoderma viride, stretomyces albolongus, alcaligenes, and arthrobacter), the highest chiti ...200818956744
polydopamine-based permanent coating capillary electrochromatography for auxin determination.a novel, simple, and economical method for the preparation of open-tubular capillary column using polydopamine coating was reported for the first time. after the capillary was filled with dopamine solution for 20h, polydopamine was formed and deposited on the inner wall of capillary as permanent coating via the oxidation of dopamine by the oxygen dissolved in the solution. moreover, the electroosmotic flow of the coated capillaries was measured to be dependent on the repetitive coating times. th ...200818945432
protection against pathogen and salt stress by four plant growth-promoting rhizobacteria isolated from pinus sp. on arabidopsis thaliana.the ability of four plant growth-promoting rhizobacteria, isolated in a previous study, to induce systemic resistance on arabidopsis thaliana col 0 against biotic and abiotic stress was evaluated. all the bacteria enhanced protection against the foliar pathogen pseudomonas syringae dc3000 and increased plant tolerance to salt stress (nacl 60 mm). bacillus sp. strain l81 and arthrobacter oxidans strain bb1 performed best with a decrease in the disease index of 61.2 and 52.3%, respectively, and a ...200818944290
interactions between strains of 2,4-diacetylphloroglucinol-producing pseudomonas fluorescens in the rhizosphere of wheat.abstract strains of fluorescent pseudomonas spp. that produce the antibiotic 2,4-diacetylphoroglucinol (2,4-dapg) are among the most effective rhizobacteria controlling diseases caused by soilborne pathogens. the genotypic diversity that exists among 2,4-dapg producers can be exploited to improve rhizosphere competence and biocontrol activity. knowing that d-genotype 2,4-dapg-producing strains are enriched in some take-all decline soils and that p. fluorescens q8r1-96, a representative d-genotyp ...200318943865
a novel aryl acylamidase from nocardia farcinica hydrolyses alkali stable polyamidase was isolated from a new strain of nocardia farcinica. the enzyme consists of four subunits with a total molecular weight of 190 kda. the polyamidase cleaved amide and ester bonds of water insoluble model substrates like adipic acid bishexylamide and bis(benzoyloxyethyl)terephthalate and hydrolyzed different soluble amides to the corresponding acid. treatment of polyamide 6 with this amidase led to an increased hydrophilicity based on rising height and tensiometry mea ...200918942140
mineralization of p-nitrophenol by a new isolate arthrobacter sp. y1.arthrobacter sp. y1, capable of metabolizing p-nitrophenol (pnp) as the sole carbon, nitrogen and energy source was isolated from activated sludge. the bacterium could tolerate concentrations of pnp up to 600 mg l(- 1), and degradation of pnp was achieved within 120 h of incubation. pnp and its metabolites were analyzed by high performance liquid chromatography (hplc). the metabolite formed indicated that the organism followed the 4-nitrocathechol (4-nc) pathway for metabolism of this compound. ...200818941993
plasmid as a measure of microbial degradation capacity for 2,4-dichlorophenoxyacetic acid.the purpose of this research was to pursuit the quantification of microbial degradation capacity for 2,4-dichlorophenoxyacetic acid (2,4-d) by detecting and quantifying a prominent 2,4-d degradation encoding plasmid. batch reactor acclimation, de-acclimation, and re-acclimation tests were conducted during which periods the courses of 2,4-d dissipation and plasmid evolution were quantitatively measured. pure cultures of bacterial strains were detected to give rise to a plasmid approximately the s ...200918930390
enzymatic characterization of an amine oxidase from arthrobacter sp. used to measure phosphatidylethanolamine.ethanolamine oxidase was screened with the aim of using it to establish a novel enzymatic phosphatidylethanolamine assay. ethanolamine oxidase activity was detected in the crude extract of arthrobacter sp., and the enzyme was purified more than 15-fold in three steps with a 54% yield. sds-page revealed the presence of only one band, which migrated, with an apparent molecular mass of 70 kda. biochemical characterization of the enzyme showed phenylethylamine to be the preferred substrate, with the ...200818838796
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