Showing papers on "Arthrobacter published in 1993"

Physicochemical Cell Surface and Adhesive Properties of Coryneform Bacteria Related to the Presence and Chain Length of Mycolic Acids

Abstract: The presence and chain length of mycolic acids of bacteria of the genera Corynebacterium, Rhodococcus, Gordona, Mycobacterium, and Arthrobacter and of coryneform bacteria containing a type B peptidoglycan were related to the cell surface hydrophobicity of the bacteria, which in turn was related to adhesion of the cells to defined surfaces such as Teflon and glass. The origin of the overall negative charge of these bacteria is discussed.

Toxicity of homologous series of organic solvents for the gram-positive bacteria Arthrobacter and Nocardia Sp. and the gram-negative bacteria Acinetobacter and Pseudomonas Sp.

Abstract: The toxicity of homologous series of organic solvents has been investigated for the gram-positive bacteria, Arthrobacter sp. and Nocardia sp., and the gram-negative bacteria, Acinetobacter sp. and Pseudomonas sp. The hydrophobicity of the solvent, expressed by its logP(octanol), proves to be a good measure for the toxicity of solvents in a two-phase system. The transition from toxic to nontoxic solvents occurs between logP(octanol) 3 and 5 and depends on the homologous series. No correlation has been found between the hydrophobicity of the substituent on the alkyl backbone of the solvent and the location of the transition point in toxicity. The logP(octanol), above which all solvents are nontoxic, is used to express the solvent tolerance of the bacteria. In general, the solvent tolerance of gram-negative bacteria is found to be slightly higher than that of gram-positive bacteria, but this does not hold for all homologous series of organic solvents investigated.Because the toxicity effects of organic solvents in a two-phase system can be ascribed to molecular as well as phase toxicity effects, molecular toxicity effects were investigated separately in a one-phase system with subsaturating amounts of organic solvent. The solvent concentration in the aqueous phase, at which 50% of the metabolic activity of the bacteria is lost, is used to express solvent toxicity. This concentration is found to be similar for the gram-positive Arthrobacter and the gram-negative Acinetobacter. Assuming the critical membrane concentration theory (G. J. Osborne et al. Enzyme Microb. Technol. 1990, 12: 281-291) to be valid, it can be concluded that differences in solvent tolerance between these two bacteria, cannot be ascribed to differences in response to molecular toxicity. Prediction of the toxicity of any solvent, using the critical membrane theory, appears to be possible in the case of alkanols or alkyl acetates. However, prediction of the toxicity of ethers appears to be impossible.

Cloning, sequencing, expression, and regulation of the structural gene for the copper/topa quinone-containing methylamine oxidase from Arthrobacter strain P1, a gram-positive facultative methylotroph.

Abstract: Deoxyoligonucleotides corresponding to amino acid sequences of methylamine oxidase and polyclonal anti-methylamine oxidase antibodies were used to probe Arthrobacter strain P1 plasmid and chromosomal DNA libraries. Two open reading frames, maoxI and maoxII, which are greater than 99% homologous, were cloned from the chromosomal library. The deduced amino acid sequences of the coding regions are identical except for two residues near the C termini. On the other hand, the 5'- and 3'-flanking regions of maoxI and maoxII are quite different. While either gene could code for methylamine oxidase, the dissimilarity in the 5'-flanking regions indicates that the genes are differently regulated. It was determined that maoxII alone encodes methylamine oxidase. The tyrosyl residue which is converted to topa quinone in the mature enzyme was located by comparison with amino acid sequences at the cofactor sites in other copper/topa quinone-containing amine oxidase. Transcriptional start sites and possible regulatory elements were identified in the 5' region of maoxI and maoxII, and stem-loop structures were found in the 3'-flanking regions. High levels of methylamine oxidase are produced when Arthrobacter strain P1 is grown on methylamine alone or on glucose plus methylamine, but growth on LB medium plus methylamine resulted in very low production of the enzyme. Expression of maoxII from its own promoter in Escherichia coli grown on glucose or LB medium with or without methylamine gave the same level of production of methylamine oxidase.

Degradation of a Sodium Acrylate Oligomer by an Arthrobacter sp

Abstract: Arthrobacter sp. strain NO-18 was first isolated from soil as a bacterium which could degrade the sodium acrylate oligomer and utilize it as the sole source of carbon. When 0.2% (wt/wt) oligomer was added to the culture medium, the acrylate oligomer was found to be degraded by 70 to 80% in 2 weeks, using gel permeation chromatography. To determine the maximum molecular weight for biodegradation, the degradation test was done with the hexamer, heptamer, and octamer, which were separated from the oligomer mixture by fractional gel permeation chromatography. The hexamer and heptamer were consumed to the extents of 58 and 36%, respectively, in 2 weeks, but the octamer was not degraded. Oligomers with three different terminal groups were synthesized to examine the effect of the different terminal groups on biodegradation, but few differences were found. Arthrobacter sp. NO-18 assimilated acrylic acid, propionic acid, glutaric acid, 2-methylglutaric acid, and 1,3,5-pentanetricarboxylic acid. Degradation of the acrylic unit structure by this strain is discussed.

Microbial degradation of chlorinated acetophenones

Abstract: A defined mixed culture, consisting of an Arthrobacter sp. and a Micrococcus sp. and able to grow with 4-chloroacetophenone as a sole source of carbon and energy, was isolated. 4-Chlorophenyl acetate, 4-chlorophenol, and 4-chlorocatechol were identified as metabolites through comparison of retention times and UV spectra with those of standard substances. The proposed pathway was further confirmed by investigation of enzymes. The roles of the two collaborating strains were studied by growth experiments and on the level of enzymes. If transient accumulation of 4-chlorophenol was avoided either by the use of phenol-absorbing substances or by careful supplement of 4-chloroacetophenone, the Arthrobacter sp. was able to grow as a pure culture with 4-chloroacetophenone as a sole source of carbon and energy. Several mono-, di-, and trichlorinated acetophenones were mineralized by the Arthrobacter sp.

Microbial production of D-malate from maleate.

Abstract: To produce D-malate from maleate by a microbial reaction, we screened a number of maleate-utilizing microorganisms for enzyme activity by an intact cell system. The strain which showed the best productivity among the 440 strains tested was identified taxonomically as Arthrobacter sp. strain MCI2612. The optical purity of the malate produced by this strain was 100% D type. The culture and reaction conditions for the production were studied for this strain. Addition of amino acids such as L-proline, L-histidine, and L-arginine to the culture medium promoted the formation of reaction activity as well as cell growth. Under optimum conditions, 87 g of D-malate per liter was produced in 20 h. The yield was 72 mol%.

Expression and secretion of an Arthrobacter dextranase in the oral bacterium Streptococcus gordonii.

Abstract: We have constructed a plasmid to express and secrete dextranase in the oral bacterium Streptococcus gordonii. The dextranase gene from Arthrobacter sp. strain CB-8 was linked to a promoter and a DNA sequence encoding the signal peptide of Streptococcus downei glucosyltransferase I (gtfI) followed by the Escherichia coli rrnBt1t2 terminator and inserted in the shuttle vector pVA838. S. gordonii transformed with this plasmid (pMNK-4) expressed and secreted mature Arthrobacter dextranase. The transformant was found to repress the firm adherence of water-insoluble glucan in a coculture experiment with cariogenic bacteria, Streptococcus sobrinus, in the presence of sucrose. Such genetically engineered oral bacteria could provide a therapy to prevent dental caries.

Spraydrying of yeast-lytic enzymes from Arthrobacter sp.

Abstract: Spray drying processes are widely used for large scale preservation of biological materials e.g milk, whey, yeast, egg white, etc. Nevertheless, there is an increasing tendency for drying of catalytic active proteins. The paper presents results from experiments which were carried out to test the applicability of spray drying for the preservation of several bacterial enzymes used for the lysis of yeast cell-walls (β-1,3-glucanase, α-mannanase, chitinase and amylase) and formed by an Arthrobacter species. Enzyme solutions were obtained by concentrating the cell free cultivation liquid by cross-flow ultrafiltration. Due to the low protein content of the liquid preparation, several substances were added as stabilizers or carriers (eg. sucrose, KCl, MgSO4) and the effect was studied in further experiments. Spray drying was carried out at inlet air temperatures of 110 – 120°C and outlet air temperatures of 65 – 72°C. Best results were obtained by the addition of 10% KCl, the preparation having a crystalline consistency and a 60% yield in activity.

Detection and comparision of strains with selective L-hydantoin cleaving activity using polyclonal antibodies

Abstract: Polyclonal antibodies were produced against the highly purified enzymes L-hydantoinase, hydantoin-racemase and L-N-carbamoylamino acid amidohydrolase of Arthrobacter aurescens DSM 3747. Using these antibodies as screening tools, a colony transfer procedure allowed the rapid detection of highly active strains. Furthermore, common Western-blot analysis enabled the direct estimation of internal enzyme concentrations, protein turnover, efficiency of different inducers and a molecular comparison of enzymes derived from different sources. Using this method it is demonstrated that of several tested microorganisms, two Arthrobacter strains showed improved production abilities.

Morphological, physiological and enzymatic characteristics of cephalosporin acylase-producing Arthrobacter strain 45-8A.

Abstract: A bacterial strain producing cephalosporin acylases was isolated from soil. The morphological and physiological properties of this strain suggest that it belongs to the genus Arthrobacter, and the isolate was therefore designated Arthrobacter strain 45-8A. Substrate specificity of the enzyme was examined. The enzyme can convert both cephalosporin C and 7β-(4-carboxylbutan-amino)cephalosporanic acid to 7-aminocephalosporanic acid. An interesting feature of the acylases is their temperature-dependent regulation. Activity of acylases was detected in strain 45-8A grown at temperature below 30 °C, but was not observed at higher temperature. Arthrobacter strain 45-8A did not exhibit β-lactamase activity, even though its resistance to cephalosporin C was very strong (>2000 μg/ml). This is quite beneficial for its application in the manufacture of 7-aminocephalosporanic acd.

D-malic acid production from maleic acid using microorganism: Screening of microorganism

Abstract: Some bacteria belonging to Arthrobacter, Brevibacterium, Corynebacterium, Pseudomonas, Bacillus, and Acinetobacter produced D-malic acid from maleic acid when the cells grown in a medium containing citraconic acid were reacted aerobically with maleic acid in the pH 7.0 phosphate buffer containing 0.1% sodium chloride.

Media optimization studies for glucose isomerase production by arthrobacter species

Abstract: Media optimization studies are carried out with the objective of maximising glucose isomerase production by Arthrobacter sp. The recommended media consists of 1.0% (w/v) xylose, 1.0% peptone, 0.5% yeast extract, 0.025% MgSO4·7H2O, 0.6% (NH4)2HPO4 and 0.2% KH2PO4. Activity of the enzyme produced in this media is 11.2 units/ml. Growth cycle for batch cultivation is studied and the lag period is 2 hours, followed by exponential phase extending upto 32 hours.

Overproduction of alanine by Arthrobacter strains with glucose-nonrepressible L-alanine dehydrogenase

Abstract: Two Arthrobacter strains were identified as having high alanine productivity and L-alanine dehydrogenase (ADH) activity upon growth on glucose. They excreted large amounts of DL-alanine (37 and 81 g/1), but Bacillus sphaericus with glucose-repressible ADH did not at all. These results suggest that the glucose-nonrepressible ADH might be involved in alanine overproduction in the Arthrobacter strains.

Immunological comparison between Arthrobacter isolates and bacteria living in Azolla filiculoides Lam

Abstract: Antisera were prepared against two Arthrobacter strains isolated from Azolla filiculoides and the type strain Arthrobacter globiformis ATCC 8010. The antisera confirmed that the bacteria associated with Azolla filiculoides-Anabaena belong to the genus Arthrobacter. Differences in the immunological reactions among the different species Arthrobacter were noted, indicating the presence of common antigens in the two forms, coccus and rod. This contributes to the knowledge of the pleomorphism of Arthrobacter. The presence of gram-positive Arthrobacter in the Azolla-Anabaena association was also confirmed by immunogold labeling of the bacteria in the leaf cavities of Azolla filiculoides.

Purification and characterization of maleate hydratase from arthrobacter sp. strain mci2612

Abstract: Maleate hydratase, which hydrates maleate to form D-malate, was purified from a crude extract of Arthrobacter sp. strain MCI2612 by DEAE-Toyopearl, Octyl-Sepharose CL-4B, and Ether-5PW column chromatographies. The enzyme was activated by sulfhydryl compounds and ferrous ion. The overall purification was 44.3-fold with a yield of 3.4%. The molecular weight of the enzyme was 90,000 by TSK G3000 SW column chromatography. The maleate hydratase appeared as two bands corresponding to molecular weights of about 58,000 and 28,000 on SDS-polyacrylamide gel electrophoresis. The enzyme had maximum activity at pH 8.5 and 45°C, and was inactivated by chemical agents such as hydroxylamine, p-chloromercuribenzoate, o-phenanthroline, and 2,2′-dipyridyl. The Km for maleate was 3.85 mM.

Biosurfactant cyclopeptide compound produced by culturing a specific Arthrobacter microorganism

Abstract: A novel biosurfactant having a high surface activity, as well as a microorganism producing the surfactant is disclosed. The biosurfactant according to the present invention is represented by the formula [I]. ##STR1## The present invention also provides Arthrobacter sp. No. 38 (FERM BP-4435) which produces the biosurfactant of the formula [I].

Enzyme formation by a yeast cell wall lytic Arthrobacter sp.: formation of \(1,3)-glucanase

Abstract: The kinetics of \-1,3-glucanase (EC 3.2.1.39; 1,3-\-d-glucan-glucano-hydrolase) formation by a yeast cell wall lytic Arthrobacter species was studied. Yeast glucan as a substrate yielded 360 units (U)/l, but it appeared to be unsuitable for fermentation purposes because of its insolubility and its residual content of glycogen. Growth on water-soluble \(1,3)-glucan [maximum specific growth rate (µmax)=0.19 h−1] was governed by different saccharides liberated by enzyme action on glucan. Enzyme formation was repressed by glucose and derepressed by its restricted availability during late exponential and stationary growth. At least 380 U/l of \(1,3)-glucanase were formed. Lactose and lactulose were detected as precursors of potent inducers for \(1,3)-glucanase, the first being a cheap and easily available substrate for large-scale cultivations. Growth rates were reduced (µmax=0.18 h−1 and µmax=0.13 h−1, respectively), enzyme synthesis occurred only during post-logarithmic growth. The \(1,3)-glucanase levels (260 U/l) formed were comparable to that attained with glucan as a substrate. In continuous culture no enzyme was formed under steady-state conditions but it occurred during transient states after shifting the dilution rate to lower values.

Gene of enzyme for asymmetric hydrolysis of ester

Abstract: PURPOSE:To provide a gene of enzyme for the asymmetric hydrolysis of esters and useful for the preparation of ester. CONSTITUTION:A gene of an enzyme capable of asymmetrically hydrolyzing the ester of chrysanthemumic acid (derivative). It can be obtained from a microbial strain capable of asymmetrically hydrolyzing an ester, e.g. Arthrobacter SC-6-98-28 (FERM BP-3618).

Azolla : an efficient N2 –fixing association with three components.

Abstract: Bacterial population is found together with the cyanobacterium Anabaena azollae in the leaf cavities and the sporocarps of Azolla. Different Arthrobacter species have been invariably isolated from the leaf cavities and sporocarps of several fern species. About the role of the bacteria in the association, it is probable that the bacteria affect the carbon and nitrogen metabolism of the cavity by competing with the Anabaena for the nutrients and in the meantime it is likely that their high respiratory activity favours the establishment of a microaerobic environment and consequently the nitrogenase activity. Furthermore Arthrobacter may contribute to the production of the mucilage present in the algal packets by excreting extracellular polysaccharides, which components can be involved in lectin binding with Azolla and Anabaena. Finally the IAA formation by Arthrobacter may influence the hormonal balance during the establishment of the association.

Process for producing L-alanine by fermentation with arthrobacter

Abstract: A process for producing L-alanine, which comprises culturing in a medium a microorganism belonging to the genus Arthrobacter which has L-alanine dehydrogenase activity, but little or no alanine racemase activity, and which is capable of producing L-alanine; allowing L-alanine to accumulate in the culture; and recovering L-alanine from the culture.

Growth of mycorrhizal fungi in dixenic cultures with bacteria in media of different composition

Abstract: Studies were carried out on the effect of bacteria: Arthrobacter globiformis, Bacillus subtilis and Pseudomonas fluorescens on biomass production by three important ectomycorrhizal fungi: Laccaria laccata, Hebeloma crustuliniforme and Rhizopogon vinicolor in media of different composition. It was shown that bacteria stimulated, inhibited or did not affect significantly the biomass production by mycorrhizal fungi. 3-factor ANOVA have shown that although effect of bacteria was statistically significant (p < or = 0.05), composition of medium and its pH affected mycelial growth stronger than bacteria.

Arthrobacter nicotiana strain, activity of the strain, method to isolate the strain, sensor with the activity and use of the strain.

Abstract: The invention relates to an Arthrobacter nicotiana strain with an acyl-CoA oxidase activity which is specific for C4-12-fatty acids, this activity, a method to isolate the activity or a strain with this activity, a sensor with the activity and its use.