Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Arthrobacter”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
PubMed1994

Cloning and sequencing of phenylethylamine oxidase from Arthrobacter globiformis and implication of Tyr-382 as the precursor to its covalently bound quinone cofactor.

The gene of Arthrobacter globiformis encoding a quinoprotein, phenylethylamine oxidase, has been cloned and sequenced. In the deduced amino acid sequence comprising 638 residues is a tetrapeptide sequence, Asn-Tyr-Asp-Tyr, which has been found to be highly conserved in other copper amine oxidase. Mutation of the former Tyr (Tyr-382) of the recombinant enzyme into Phe resulted in the complete loss of catalytic activity and disappearance of the quinone compound that is specifically detected in the wild-type enzyme, suggesting that Tyr-382 is the precursor to the covalently-bound cofactor, most probably topa quinone. Furthermore, the expression of the active, quinone-containing enzyme in Escherichia coli cells was markedly dependent on the presence of Cu2+ ions in the culture medium, and the inactive, Cu2(+)-deficient enzyme produced without Cu2+ ions could be converted to the active quinone form by reconstitution with Cu2+ ions.

Amine Oxidase (Copper-Containing)↗
PubMed1997

Isolation of ALU1-P gene encoding a protein with aluminum tolerance activity from Arthrobacter viscosus.

We isolated a DNA fragment (ALU1-P) encoding a protein with an activity of aluminum tolerance from an Al tolerant soil microorganism, Arthrobacter viscosus. This microorganism was isolated from acidic tea field soils. The cloned DNA is composed of 1090 nucleotides, which has one open-reading frame without any stop codon. However, when the DNA fragment was transferred into Escherichia coli, a microorganism susceptible to Al toxicity, it endowed E. coli with Al tolerance. The deduced amino acid sequence of the DNA showed 65% identity with the protein of YbaX gene in Escherichia coli, and 51.1% identity with YB91 Haein hypothetical protein of HI1191 gene in Haemophilus influenzae. The ALU1-P gene in the expression vector produced a protein of 192 amino acids deriving a molecular weight of 21.3 kDa by using the stop codon in vector. The ALU1-P gene is a new one that has the characteristic of Al tolerance.

Aluminum↗
PubMed2000

Degradation of o-nitrobenzoate via anthranilic acid (o-aminobenzoate) by Arthrobacter protophormiae: a plasmid-encoded new pathway.

An Arthrobacter protophormiae strain RKJ100, isolated by selective enrichment, was capable of utilizing o-nitrobenzoate (ONB(+)) as the sole carbon, nitrogen, and energy source. The degradation of ONB proceeds through an oxygen insensitive reductive route as shown by the release of ammonia in the culture medium aerobically rather than nitrite ions. Thin-layer chromatography, gas chromatography, and gas chromatography-mass spectrometry of the intermediates have shown that ONB is degraded by a two-electron reduction of the nitro moiety, yielding o-hydroxylaminobenzoate and anthranilic acid. Quantitation of the intermediates, inhibition studies, and simultaneous induction studies have shown that anthranilic acid is produced as the terminal aromatic intermediate of a catabolic energy-yielding pathway and not as a side reaction taking place concurrently which is the first such report. A plasmid of approximately 65 kb was found to be responsible for harboring genes for ONB degradation in this strain. The same plasmid also encoded resistance to cobalt ions.

Aerobiosis↗
PubMed2000

Plasmid-encoded degradation of p-nitrophenol and 4-nitrocatechol by Arthrobacter protophormiae.

Arthrobacter protophormiae strain RKJ100 is capable of utilizing p-nitrophenol (PNP) as well as 4-nitrocatechol (NC) as the sole source of carbon, nitrogen and energy. The degradation of PNP and NC by this microorganism takes place through an oxidative route, as stoichiometry of nitrite molecules was observed when the strain was grown on PNP or NC as sole carbon and energy sources. The degradative pathways of PNP and NC were elucidated on the basis of enzyme assays and chemical characterization of the intermediates by TLC, GC, (1)H NMR, GC-MS, UV spectroscopy, and HPLC analyses. Our studies clearly indicate that the degradation of PNP proceeds with the formation of p-benzoquinone (BQ) and hydroquinone (HQ) and is further degraded via the beta-ketoadipate pathway. Degradation of NC involved initial oxidation to generate 1,2,4-benzenetriol (BT) and 2-hydroxy-1,4-benzoquinone; the latter intermediate is then reductively dehydroxylated, forming BQ and HQ, and is further cleaved via beta-ketoadipate to TCA intermediates. It is likely, therefore, that the same set of genes encode the further metabolism of HQ in PNP and NC degradation. A plasmid of approximately 65 kb was found to be responsible for harboring genes for PNP and NC degradation in this strain. This was based on the fact that PNP(-) NC(-) derivatives were devoid of the plasmid and had simultaneously lost their capability to grow at the expense of these nitroaromatic compounds.

Arthrobacter↗
PubMed1998

Gene structures and properties of enzymes of the plasmid-encoded nicotine catabolism of Arthrobacter nicotinovorans.

Arthrobacter nicotinovorans is a Gram-positive aerobic soil bacterium able to grow on nicotine as its sole source of carbon and nitrogen. The initial steps of nicotine catabolism are catalyzed by nicotine dehydrogenase, the l- and d-specific 6-hydroxynicotine oxidases, and ketone dehydrogenase. The genes encoding these enzymes reside on a 160 kb plasmid, pAO1. The cccDNA of this plasmid was isolated in high purity and reasonable yield. It served as template material for the construction of a lambda-phage DNA library of the plasmid. The genes coding for 6-hydroxy-l-nicotine oxidase and for the subunits of the heterotrimeric ketone dehydrogenase were identified, subcloned and sequenced. The 6-hlno gene was identified as a 1278 bp open reading frame; its regulatory elements were also recognized. The derived primary structure of the monomer of apo-6-hydroxy-l-nicotine oxidase (46,264.5 Da) agrees with the data obtained by partial amino acid sequencing. 6-Hydroxy-l-nicotine oxidase and 6-hydroxy-d-nicotine oxidase were expressed in Escherichia coli and obtained in a state of high purity and crystallized. Ketone dehydrogenase (KDH) was found to be a heterotrimer with subunits of molecular mass 89,021.71, 26,778.65 and 17,638.88. The genes of KDH-A and KDH-B are juxtaposed; the A of the stop codon of KDH-A is used in the start codon of KDH-B, eliciting a frame shift. KDH-C is separated from KDH-A by 281 bp.

Arthrobacter↗
PubMed2001

Construction, overexpression, and purification of Arthrobacter globiformis amine oxidase-Strep-tag II fusion protein.

The copper-containing amine oxidase from Arthrobacter globiformis has been expressed and purified as a fusion protein with a C-terminal Strep-tag II peptide. This tag facilitates the rapid purification of the enzyme on a large scale using the StrepTactin POROS medium. For example, we have demonstrated that 50 mg of protein can be obtained in 2 days from 2 L of Escherichia coli. The purified fusion protein displays turnover and spectroscopic properties that are essentially identical to those of the wild-type enzyme. Given the location of the C-terminus in four amine oxidase crystal structures, this strategy should be quite general for the rapid purification of amine oxidases from multiple sources.

Amine Oxidase (Copper-Containing)↗
PubMed1990

Methylamine oxidase from Arthrobacter P1 as a prototype of eukaryotic plasma amine oxidase and diamine oxidase.

Methylamine oxidase (MAOx) from Gram-positive soil bacterium Arthrobacter P1 catalyzes the oxidation of CH3NH2 to H2C = O and NH4+ via reduction of O2 to H2O2. Past work indicates that MAOx is similar to mammalian plasma amine oxidase (PAO) and diamine oxidase (DAO), plant DAO, and yeast peroxisomal amine oxidase (YAO). All have Mr congruent to 170,000 and are composed of 2 identical subunits, each of which contains 1 atom of Cu(II) and one molecule of quinonoid cofactor. Herein, we report further evidence as to the striking similarity of these enzymes, and describe properties of MAOx which offer insights into understanding the eukaryotic oxidases. It is our belief that the structure of the quinone cofactor, and the Cu(II) site in MAOx are identical to these sites in PAO and DAO.

Amine Oxidase (Copper-Containing)↗
PubMed1991

Evidence for two distinct phosphonate-degrading enzymes (C-P lyases) in Arthrobacter sp. GLP-1.

Arthrobacter sp. GLP-1 can utilize a wide range of organophosphonates as its sole source of phosphorus. The in-situ formation of sarcosine and methane from glyphosate and methanephosphonic acid respectively was studied. These two processes are differentially induced during phosphorus-deprivation. Methanephosphonic acid strongly inhibits glyphosate degradation (I50 10 microM), but glyphosate has very little effect on methane generation (I50 150 mM). The pattern of inhibition by other organophosphonates and organophosphonate analogues is also very different for the two systems. Degradation of glyphosate and methanephosphonic acid therefore represent distinct processes.

Arthrobacter↗
PubMed1995

Secretory overproduction of Arthrobacter simplex 3-ketosteroid delta 1-dehydrogenase by Streptomyces lividans with a multi-copy shuttle vector.

The gene for 3-ketosteroid delta 1-dehydrogenase (ksdD) of Arthrobacter simplex was expressed in Streptomyces lividans and the secreted enzyme was overproduced by using a multi-copy shuttle vector composed of pIJ702 and pUC19. Deletional analysis of the recombinant plasmid showed that the entire coding sequence of the ksdD gene was located within a 7-kb segment of the chromosomal DNA obtained from the enzyme-producing strain of A. simplex. When S. lividans carrying the recombinant plasmid was grown in an appropriate medium, the cells produced about 100-fold more 3-ketosteroid delta 1-dehydrogenase than the original strain. Although the percentage of enzyme secreted was changed during cultivation, a maximum 55% of the enzyme was secreted into the cultured medium of S. lividans, while A. simplex did not produce the enzyme extracellularly. Secretory overproduction of 3-ketosteroid delta 1-dehydrogenase in S. lividans was also identified by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and on native gel, and the enzyme reaction was confirmed by reverse-phase HPLC using 4-androstene-3,17-dione as a substrate.

Androstadienes↗
PubMed1990

Trimethyl lead degradation by free and immobilized cells of an Arthrobacter sp. and by the wood decay fungus Phaeolus schweinitzii.

The continuing production of leaded petrol generates liquid wastes containing recalcitrant trialkyl lead, for which no suitable chemical treatment has been formulated. This investigation explores the feasibility of using microorganisms to catalyse the rate-limiting step of trimethyl lead degradation to dialkyl lead; this disproportionates chemically to give, ultimately, Pb2+ which is treatable by classical methods. An Arthrobacter sp. and a wood decay macrofungus, Phaeolus schweinitzii provide novel evidence for metabolic trimethyl lead (Me3Pb+) degradation. The retention of this activity in immobilized cell column reactors challenged with Me3Pb(+)-supplemented flows suggests that a future biotreatment process may be possible.

Arthrobacter↗
PubMed1990

The use of free and immobilised Arthrobacter simplex in organic solvent/aqueous two-liquid-phase reactors.

The use of free and immobilised Arthrobacter simplex (NCIB 8929) for steroid delta 1-dehydrogenation in two-liquid-phase, stirred-tank reactors has been compared. Product formation is related to the logarithm of the water-octanol partition coefficient (log P) of the organic solvent employed, but the relationship is different for the two forms of the biocatalyst. No reaction was seen with either biocatalyst in media containing solvents of log P less than or equal to 2.5. For free bacteria, product formation rose linearly with log P thereafter to a maximum at a value of 9.8. With immobilised bacteria, product formation reached a maximum with a solvent of log P = 4.0 and remained constant with solvents of higher log P value. Consequently extended reactor operation was possible with immobilised bacteria, and the production of high quality (greater than 95% purity) steroid product was demonstrated.

Arthrobacter↗
PubMed1990

Functional analysis of the 5' regulatory region and the UUG translation initiation codon of the Arthrobacter oxidans 6-hydroxy-D-nicotine oxidase gene.

A functional analysis of the Arthrobacter oxidans 6-hydroxy-D-nicotine oxidase (6-HDNO) gene promoter (-35 region TTGACA and -10 region TATCAAT) and the UUG translation start codon was performed using site-directed mutagenesis. Deletion of the C residue from the -10 promoter region or mutations introduced upstream of the -10 region resulted in an increased 6-HDNO expression in Escherichia coli cells in vivo and in both E. coli and A. oxidans coupled transcription-translation systems in vitro. From the identical behaviour of 6-HDNO promoter mutants in the heterologous and homologous systems, it is concluded that A. oxidans harbours an RNA polymerase functionally homologous to the E. coli sigma 70 and Bacillus subtilis sigma 43 polymerases. Replacement of the TTG codon (UUG translation initiation codon) with ATG led to a 3.7-fold increase in 6-HDNO expression in E. coli. This effect was less pronounced at higher promoter strengths, from 3.7 in the case of the 6-HDNO wild-type promoter, to 2.5 in the case of the consensus -10 region and to 1.7 in the case of the tac promoter. A double point mutation introduced close to the ribosome binding site resulted in almost the same increase in 6-HDNO expression (3.1-fold) as the TTG-to-ATG exchange. The failure of cAMP to stimulate 6-HDNO expression in the A. oxidans system indicated that expression of this gene in stationary phase cells is not regulated by cAMP-catabolite repressore protein-mediated mechanism of catabolite repression.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthrobacter↗
PubMed1986

Plasmid pAO1 of Arthrobacter oxidans encodes 6-hydroxy-D-nicotine oxidase: cloning and expression of the gene in Escherichia coli.

The 160 kb plasmid pAO1 from Arthrobacter oxidans (Brandsch and Decker 1984) was subcloned in Escherichia coli with the aid of the plasmid vectors pUR222 and pBR322. Screening of the recombinant clones for enzyme activity revealed that the flavoenzyme 6-hydroxy-D-nicotine oxidase (6-HDNO), one of the enzymes of the nicotine-degradative pathway in A. oxidans, is encoded on pAO1. Immunoprecipitation of 35S-methionine-labelled E. coli cells with 6-HDNO-specific antiserum and expression of recombinant plasmid DNA in E. coli "maxicells" revealed that 6-HDNO is made as a 52,000 dalton protein, approximately 4,500 daltons larger than 6-HDNO from A. oxidans. The 6-HDNO activity was constitutively expressed in E. coli cells, possibly from an A. oxidans promoter, as shown by subcloning of the 6-HDNO gene in pBR322, using the expression vector pKK223-3 and the promoter probe vector pCB192.

Arthrobacter↗
PubMed1978

Regulation of flavoprotein synthesis studied in vivo in a riboflavin-requiring mutant of Arthrobacter oxidans.

The biosynthesis of two flavoproteins, 6-hydroxy-D-nicotine oxidase with covalently bound FAD and 6-hydroxy-L-nicotine oxidase containing non-covalently bound FAD, was studied in wild-type cells and in a riboflavin-requiring mutant of Arthrobacter oxidans. In the mutant cells, the rate of synthesis and the maximal activity level of both enzymes after induction by nicotine depended on the amount of added riboflavin. The low rate of synthesis in the presence of 2 micron riboflavin could be enhanced during the induction phase by further addition of riboflavin (33 micron). Inhibitors of translation (chloramphenicol or streptomycin) completely blocked the synthesis of both flavoproteins. Inhibitors of transcription (rifamycin S or actinomycin D) stopped the synthesis of both enantiozymes in wild-type cells and in the mutant grown in the presence of a saturating supply of riboflavin (15 micron). Under conditions of restricted flavoprotein synthesis (2 micron riboflavin in the medium), however, the mutant cells continued to synthesize the enzyme for 2--3 h after the addition of the transcription inhibitors. It appears, that in these cells a rather stable m-RNA accumulated during riboflavin-limited flavoprotein synthesis. The dependence of the effect of transcription inhibitors on the extracellular supply of riboflavin suggests that the regulation of the synthesis of both flavoproteins occurs not only by control of gene expression (induction by nicotine), but also at the level of translation through the availability of FAD.

Arthrobacter↗
PubMed1979

Adenosine triphosphate pool levels and endogenous metabolism in Arthrobacter crystallopoietes during growth and starvation.

The adenosine triphosphate (ATP) content of Arthrobacter crystallopoietes was measured during growth, starvation and recovery from starvation. During exponential growth of the cells as spheres in a glucose slats medium, the level of ATP per cell remained constant at 8.0 x 10(-10) micrograms/cell. Morphogenesis to rodshaped cells and an increased growth rate following addition of casein hydrolysate was accompanied by an almost two-fold increase in the ATP level. As division of the rod-shaped cells proceeded, the level of ATP declined. After growing as rods for 12-14 h the cells underwent fragmentation to spheres during which time the ATP level again increased to the original value of 8.0 x 10(-10) micrograms/cell. As the spherical cells resumed growth on the residual glucose, their ATP content declined for a short period and then remained relatively constant. During starvation of sphere or rod-shaped cells for one week, the ATP level declined by approximately 70% during the first 40-50 h and then remained constant. The endogenous metabolism rate of spherical cells declined during the first 10-20 h of starvation and then remained constant at approximately 0.02% of the cell carbon being utilized per h. Addition of glucose to spherical cells which had been starved for one week increased both the ATP content per cell and their rate of endogenous metabolism. The ATP content fluctuated and then remained at a level higher than maintained during starvation while endogenous metabolism quickly declined.

Adenosine Triphosphate↗
PubMed1979

Adenylate nucleotide levels and energy charge in Arthrobacter crystallopoietes during growth and starvation.

The adenylate nucleotide concentrations, based on internal water space, were determined in cells of Arthrobacter crystallopoietes during growth and starvation and the energy charge of the cells was calculated. The energy charge of spherical cells rose during the first 10 h of growth, then remained nearly constant for as long as 20 h into the stationary phase. The energy charge of rod-shaped cells rose during the first 4 h of growth, then remained constant during subsequent growth and decreased in the stationary growth phase. Both spherical and rod-shaped cells excreted adenosine monophosphate but not adenosine triphosphate or adenosine diphosphate during starvation. The intracellular energy charge of spherical cells declined during the initial 10 h and then remained constant for 1 week of starvation at a value of 0.78. The intracellular energy charge of rod-shaped cells declined during the first 24 h of starvation, remained constant for the next 80 h, then decreased to a value of 0.73 after a total of 168 h starvation. Both cell forms remained more than 90% viable during this time. Addition of a carbon and energy source to starving cells resulted in an increase in the ATP concentration and as a result the energy charge increased to the smae levels as found during growth.

Adenine Nucleotides↗
PubMed1981

Arthrobacter P1, a fast growing versatile methylotroph with amine oxidase as a key enzyme in the metabolism of methylated amines.

A facultative methylotrophic bacterium was isolated from enrichment cultures containing methylamine as the sole carbon source. It was tentatively identified as an Arthrobacter species. Extracts of cells grown on methylamine or ethylamine contained high levels of amine oxidase (E.C. 1.4.3) activity. Glucose- or choline-grown cells lacked this enzyme. Oxidation of primary amines by the enzyme resulted in the formation of H2O2; as a consequence high levels of catalase were present in methylamine- and ethylamine-grown cells. The significance of catalase in vivo was demonstrated by addition of 20 mM aminotriazole (a catalase inhibitor) to exponentially growing cells. This completely blocked growth on methylamine whereas growth on glucose was hardly affected. Cytochemical studies showed that methylamine-dependent H2O2 production mainly occurred on invaginations of the cytoplasmic membrane. Assimilation of formaldehyde which is generated during methylamine oxidation was by the FBP variant of the RuMP cycle of formaldehyde fixation. The absence of NAD-dependent formaldehyde and formate dehydrogenases indicated the operation of a non-linear oxidation sequence for formaldehyde via hexulose phosphate synthase. Enzyme profiles of the organism grown on various substrates suggested that the synthesis of amine oxidase, catalase and the enzymes of the RuMP cycle is not under coordinate control.

Amine Oxidase (Copper-Containing)↗