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PubMed1991

Purification of solanesyl-diphosphate synthase from Micrococcus luteus. A new class of prenyltransferase.

The activity of solanesyl-diphosphate synthase from Micrococcus luteus is stimulated by a high molecular mass fraction (HMF) which is separated from cell-free extracts of the same bacterium by DEAE-Toyopearl chromatography followed by Sephadex G-100 chromatography. By employing HMF in the assay procedure, solanesyl-diphosphate synthase was able to be purified to homogeneity and was found to be a homodimer with a monomeric molecular mass of 34 kDa. In contrast to hexaprenyl- and heptaprenyl-diphosphate synthases, which are composed of two easily dissociable components that are inactive unless combined, the homogeneously purified solanesyl-diphosphate synthase itself showed a catalytic activity, though weak, catalyzing the synthesis of both (all-E)-nonaprenyl-(solanesyl-) and (all-E)-octaprenyl diphosphate. HMF does not affect the stability of solanesyl-diphosphate synthase or Km values for isopentenyl diphosphate and farnesyl diphosphate, but it markedly increases Vmax values in a time-dependent manner. Several lines of evidence indicate that HMF contains a factor which binds to polyprenyl products and removes them out of the active site of enzyme to facilitate and maintain the turnover of catalysis.

Alkyl and Aryl Transferases↗
PubMed1991

Cell separation system studied by mixed culture of single wild strain with tetrads-forming mutant strain of Micrococcus luteus.

Mixed culture study of singly occurring wild strain IFO 3333 of Micrococcus luteus and a tetrads-forming mutant strain MT, in the absence or presence of trypsin, supported our previous assumption that at least two kinds of separation systems were involved in cell separation of M. luteus, the one having a physiological role in cutting off the outermost layer of the cell wall (separation system-Om) and the other in cutting off the inner layer of the "proper" cell wall or the septum (separation system-In). The separation system-Om of IFO 3333 insensitive to trypsin substituted, freely from the cells, for that of MT sensitive to trypsin.

Micrococcus luteus↗
PubMed1991

Identification and characterization of RNA polymerase sigma factor from Micrococcus luteus.

The promoters of Micrococcus luteus, a bacterium whose chromosomal DNA has a high G + C content (74%), diverge from the consensus prokaryotic promoter in having GC-rich DNA sequences at less important positions (Nakayama, M., Fujita, N., Ohama, T., Osawa, S., and Ishihama, A. (1989) Mol. Gen. Genet. 218, 384-389). In order to compare the promoter selectivity of RNA polymerase between M. luteus and Escherichia coli, we purified the enzyme from both organisms. The sets of promoters recognized by the two RNA polymerases were found to overlap partly. Some, but not all, E. coli promoters were found to be correctly transcribed in vitro by M. luteus RNA polymerase as well as the E. coli enzyme. One molecular species of M. luteus sigma factor, with the apparent molecular mass of 60 kDa, was isolated from purified RNA polymerase. By the addition of either M. luteus or E. coli core enzyme it was reconstituted into active holoenzyme. Likewise, M. luteus core enzyme was reconstituted into a hybrid holoenzyme by the addition of E. coli sigma subunit. Both hybrid holoenzymes were, however, able to initiate transcription only from promoters which were recognized by both of the native holoenzymes.

Binding, Competitive↗
PubMed1991

Interconversion of radical and nitrone forms of lysodektose--a new trisaccharide from Micrococcus lysodeikticus.

Isolated from Micrococcus lysodeikticus, 6-O-(2-deoxy-2-(N-methyl)hydroxilamino-beta-D-glucopyranosyl)-alph a-alpha- trehalose (lysodektose) is oxidized by K3Fe(CN)6 in a stepwise manner to become a nitroxyl radical and a nitrone with a double bond in the fragment O-N = CH2 which could be reduced to the original hydroxylamine form with sodium borohydride. Thus derivatives of lysodektose specifically labelled with 2H and (or) 3H in the methyl group are easily obtained. When oxidized in cells poisoned with vitamin K analogues, lysodektose is transformed into nitrone concomitant with modification of its methyl group. Participation in the antioxidant defence of the bacteria is suggested for this new trisaccharide.

Carbohydrate Sequence↗
PubMed1990

Chemical treatments of the cell packets induced from a Micrococcus luteus mutant and teichuronic acids on the packet surface.

Cell packets (MT packets) induced from a tetrads-forming mutant (strain MT) of Micrococcus luteus, both treated with chemical reagents and non-treated, were observed with a scanning electron microscope (SEM). The agglutinability of MT packets with antiserum containing anti-teichuronic acid antibody was examined. The binding of protein A-gold particles to the MT packets, mediated with the antiserum, was also observed with SEM. Gold particles were observed uniformly on the whole packet surface and also on the bridging structure formed by the outermost layer of the cell wall. Mild acid treatment, NaIO4-NaBH4 treatment and mild Smith degradation of the MT packets extremely decreased the agglutinability and binding of protein A-gold particles. The treatments gave a little influence on the surface feature and appreciably destroyed the regular packet structure. It was supposed that teichuronic acids distributed uniformly on the whole packet surface, naturally on the surface of the bridging structure too, and appreciably participated in the maintenance of the regular packet structure.

Cell Membrane↗
PubMedDate not supplied

[Some properties of beta-aspartate kinase from Micrococcus glutamicus-95 bacteria].

Kinetic and allosteric properties of beta-asparatatekinase from Micrococcus glutamicus-95 were studied. Coarse protein fraction, sedimented at 0.8 from saturated (NH4)2SO4, was used as an enzyme preparation. Curves of the dependency of the enzymatic reaction rate on substrate (L-aspartic acid and ATP) concentration were not found to be S-like. However, double reciprocal plotting of the data obtained revealed their deviation from the hyperbolic curve. The effect of amino acids (lysine, threonine, isoleucine, valine) on the activity of beta-aspartatekinase is studied. Lysine was shown to inhibit slightly beta-aspartatekinase, while threonine slightly activated it. Combined addition of both amino acids at a concentration of 1 mM resulted in the 50% inhibition. Isoleucine and valine activated beta-aspartatekinase and eliminated multivalent inhibitory effect of lysine and threonine. Interaction of isoleucine and lysine+threonine with beta-aspartatekinase was competitive with respect to L-aspartic acid and non-competitive in relation to ATP.

Adenosine Triphosphate↗
PubMedDate not supplied

[Thermal inactivation and stabilization of lysozyme substrate-- Micrococcus lysodeicticus cells].

Heat inactivation of the acetonic powder of Micrococcus lysodeicticus cells suspended in phosphate buffer pH 6.2 was quantitatively characterized in the temperature range from 34 to 52 degrees. The total value of the rate constant for heat inactivation of the cells equals 2.88 X 10(8) exp(-18360/RT) sec-1. The activation parameters of the process at 34 degrees are the following: delta H* = 17.7 kcal/mole; delta S* = 21.8 E. U.; delta F* = 24.4 kcal/mole. The effect of ethylene glycol, mannitol, dextran, polyvinyl alcohol (PVA) and polyethylene glycols with different molecular weights on the lysis rate and cell stability was studied. Polyvinyl alcohol was found to be the most effective stabilizer. At concentrations of about 10(-5) it enhances the thermostability of the cells threefold.

Dextrans↗
PubMed1989

Modulation of the DNA scanning activity of the Micrococcus luteus UV endonuclease.

Micrococcus luteus UV endonuclease incises DNA at the sites of ultraviolet (UV) light-induced pyrimidine dimers. The mechanism of incision has been previously shown to be a glycosylic bond cleavage at the 5'-pyrimidine of the dimer followed by an apyrimidine endonuclease activity which cleaves the phosphodiester backbone between the pyrimidines. The process by which M. luteus UV endonuclease locates pyrimidine dimers within a population of UV-irradiated plasmids was shown to occur, in vitro, by a processive or "sliding" mechanism on non-target DNA as opposed to a distributive or "random hit" mechanism. Form I plasmid DNA containing 25 dimers per molecule was incubated with M. luteus UV endonuclease in time course reactions. The three topological forms of plasmid DNA generated were analyzed by agarose gel electrophoresis. When the enzyme encounters a pyrimidine dimer, it is significantly more likely to make only the glycosylase cleavage as opposed to making both the glycosylic and phosphodiester bond cleavages. Thus, plasmids are accumulated with many alkaline-labile sites relative to single-stranded breaks. In addition, reactions were performed at both pH 8.0 and pH 6.0, in the absence of NaCl, as well as 25,100, and 250 mM NaCl. The efficiency of the DNA scanning reaction was shown to be dependent on both the ionic strength and pH of the reaction. At low ionic strengths, the reaction was shown to proceed by a processive mechanism and shifted to a distributive mechanism as the ionic strength of the reaction increased. Processivity at pH 8.0 is shown to be more sensitive to increases in ionic strength than reactions performed at pH 6.0.

DNA↗
PubMedDate not supplied

An economical large-scale procedure to purify Micrococcus plasmid DNA.

A reproducible and economical procedure for obtaining a large yield of highly purified covalently closed circular (ccc) plasmid DNA from an industrially important strain of Micrococcus is described. The procedure adopted here departs in several ways from commonly used protocols for isolation of plasmid DNA from Gram (positive) and Gram (negative) bacteria. The plasmid DNA prepared by this procedure is free of contaminants and is pure enough to be used for electron microscopy, DNA transformation, sequencing, in vitro transcription and mutagenesis.

Biotechnology↗
PubMed1985

Topography in relation to activity of the F1-ATPase of Micrococcus lysodeikticus (M. luteus): a study using trypsin digestion and hydrophobic interaction chromatography.

Micrococcus lysodeikticus (M. luteus) ATPase digested in a controlled manner with trypsin behaves like the native protein when chromatographed on alkyl agarose supports. The enzyme immobilized on the supports through noncovalent interaction is able to hydrolyze ATP with a specific activity similar to that of native membrane-bound ATPase. However, the response of M. lysodeikticus ATPase to the interaction with the hydrophobic columns can be modified by changing the protein-ligand ratio. These results support the notion that the catalytic site of M. lysodeikticus ATPase is not involved in the interaction with alkyl agarose, but rather that binding of the ATPase to the hydrophobic columns takes place through polypeptide or protein domains other than those which mediate binding to the native membranes, since they are very easily modified by trypsin. It is proposed that the alpha subunit plays a role in the interaction of the bacterial ATPase with hydrophobic ligands. These results are discussed in relation to the topography of the enzyme as established previously.

Binding Sites↗
PubMed1977

Micrococcus luteus correndonucleases. II. Mechanism of action of two endonucleases specific for DNA containing pyrimidine dimers.

Py pyrimidine dimers Py correndonucleases I and II from Micrococcus luteus act exclusively on thymine-thymine, cytosine-cytosine, and thymine-cytosine cyclobutyl dimers in DNA, catalyzing incision 5' to the damage and generating 3'-hydroxyl and 5'-phosphoryl termini. Both enzymes initiate excision of pyrimidine dimers in vitro by correxonucleases and DNA polymerase I. The respective incised DNAs, however, differ in their ability to act as substrate for phage T4 polynucleotide ligase or bacterial alkaline phosphatase, suggesting that each endonuclease is specific for a conformationally unique site. The possibility that their respective action generates termini which represent different degrees of single strandedness is suggested by the unequal protection by Escherichia coli binding protein from the hydrolytic action of exonuclease VII.

Alkaline Phosphatase↗
PubMed1988

Gamma endonuclease of Micrococcus luteus: action on irradiated DNA.

Gamma endonuclease is a Mg2+-independent enzyme of Micrococcus luteus that recognizes and cleaves DNA at a variety of altered pyrimidines produced by ionizing radiation. The production of enzyme-recognizable sites (ERS) by ionizing radiation under different irradiation conditions was measured. Ionizing radiation produced the greatest number of ERS when irradiations were performed under anoxic conditions in the presence of the free radical scavenger KI. Since dihydrothymine is a major pyrimidine lesion produced in DNA during anoxic irradiation, the ability of gamma endonuclease to excise this lesion was assessed. Dihydrothymine was released from DNA irradiated under anoxic conditions in a radiation dose-dependent manner, consistent with gamma endonuclease's known DNA glycosylase activity. Gamma endonuclease was also shown to cleave heavily uv-irradiated DNA. When the sequence specificity of gamma-endonuclease cleavage was studied using uv-irradiated DNA, cleavage was seen specifically at cytosines. The identity of this enzyme-recognizable cytosine photoproduct is not known.

Cobalt Radioisotopes↗
PubMed1986

[Localization of cysteine residues in the alpha-chain of histidine decarboxylase from Micrococcus sp. n].

It was shown that the alpha-chain of histidine decarboxylase of Micrococcus sp. n. is split off by 2-nitro-5-thiocyanobenzoic acid at only one of the two cysteine residues. Determination of the C-terminal sequences, amino acid composition, molecular weight of the fragments obtained demonstrated that these fragments constitute a complete alpha-chain whose cleavage occurs at the cysteine residue which is readily modified by SH-reagents. the Ile-Cys peptide bond appeared to be resistant to cleavage under these conditions. This cleavage permitted to identify the amino acid environment of the cysteine residue active center and its localization in the alpha-chain of histidine decarboxylase.

Amino Acid Sequence↗
PubMed1979

Affinity chromatography of putrescine oxidase from Micrococcus rubens and spermidine dehydrogenase from Serratia marcescens.

Putrescine oxidase [EC 1.4.3.4], putrescine : oxygen oxidoreductase (deaminating) (flavin-containing), from Micrococcus rubens and spermidine dehydrogenase from Serratia marcescens were adsorbed on amine-Sepharose 4B in which one of the terminal amino groups of diamine or triamine was covalently bound to Sepharose 4B leaving the other terminal amino group(s) free. The affinities of these enzymes for the amine-Sepharose 4B increased on increasing the chain length of the methylene groups in the immobilized amines and fell upon addition of the substrate. The affinity of putrescine oxidase modified with 1-ethyl-3-(3-dimethylamino-propyl)-carbodiimide (EDC) was reduced in comparison with that of the native enzyme so far as 1,12-diaminododecane-Sepharose 4B was concerned. From these results, it can be concluded that the interactions between the enzyme and the amine-Sepharose result from specific affinities mediated through the active sites of the enzymes. It is suggested that spermidine dehydrogenase as well as putrescine oxidase has as anionic point and a hydrophobic region in the active site. On the basis of these results, the applicability of the enzyme affinities to purification procedures was examined. When partially purified enzymes were subjected to affinity chromatography, the following results were obtained. Putrescine oxidase gave a purification factor of 40-fold with about 100% recovery on a 1,12-diaminododecane-Sepharose column. In the case of spermidine dehydrogenase, the purification factor and recovery on a 1,8-diaminooctane-Sepharose column were about 1,200-fold and 86%, respectively. By introducing affinity chromatography as a purification step, each enzyme could be purified more simply and with higher recovery.

Chromatography, Affinity↗
PubMed1985

Isolation and characterization of a succinylated polysaccharide from the cell wall of Micrococcus agilis.

A polysaccharide consisting of rhamnose, galactose, glucosamine and ester-linked succinic acid was extracted from the isolated cell walls of Micrococcus agilis by the hot water-phenol and 5% trichloroacetic acid (TCA) extraction methods. The hot water-phenol extractable polysaccharide accounted for 30% of the weight of the wall, with 23% by the TCA method. Phosphorus contents were less than 0.01% of the polysaccharide. Succinyl residues released by alkali treatment (0.1 N NaOH, 30 min, 37 degrees C) were identified by gas-liquid chromatography, and accounted for 6.3% and 5.1% of the polysaccharide purified from the hot water-phenol and TCA extracts, respectively. The polysaccharide was not bound when chromatography on Concanavalin A-Sepharose 4B (Con A/Sepharose 4B) columns was performed and it could thus be separated from any residual membrane lipomannan. The purified polysaccharide behaved as a negatively-charged polymer on electrophoresis in 1% agarose (at pH 8.6). A strong cross-reaction, unaffected by removal of the succinyl groups, was observed with type XXIII pneumococcal polysaccharide antiserum indicating the presence of L-rhamnose, linked through non-reducing, lateral end groups.

Antigen-Antibody Complex↗
PubMed1985

The phosphate diester linkage of the peptidoglycan polysaccharide moieties of Micrococcus lysodeikticus cell wall.

The external polysaccharide is a major component of Micrococcus lysodeikticus cell wall and displays distinct composition. The complete structure of the external polysaccharide had been elucidated as a basis for investigation of the cell wall structure-function relation. However, the mode of attachment of the polysaccharide to the peptidoglycan through a phosphodiester was not clear due to limitations in structural and biosynthetic studies. The present study describes purification of a lysozyme-resistant nondialyzable high-molecular-weight fragment of cell wall and identifies the sugar, D-glucose, as the point of external polysaccharide attachment to the peptidoglycan through a phosphate diester. Kinetic studies for the acid-catalyzed release of external polysaccharide from the peptidoglycan were performed in parallel with synthetic [methyl-2-acetamido-3-O-(D-1-carboxyethyl)-2-deoxy-alpha-D- glucopyranoside-6-yl]-alpha-D-glucopyranosyl phosphate and alpha-D-glucopyranosyl phosphate and showed the presence of a phosphodiester linkage between external polysaccharide and peptidoglycan. In addition, type of phosphate residue and cross-linking between muramic acid and protein part have been determined.

Amino Acids↗
PubMed1975

Isolation and characterization of homogenous rabbit antibodies to Micrococcus lysodeikticus with specificity to the peptidoglycan and to the glucose-N-acetylaminomannuronic acid polymer.

The antibody response of rabbits to Micrococcus lysodeikticus is characterized by the production of a high concentration of antibodies which manifest markedly reduced heterogenicity. The specificity of these antibodies was studied and it revealed that M. lysodeikticus contains 2 major antigens: both the glucose-N-acetyl-aminomannuronic acid polymer obtained by formamide extraction of the cell walls and peptidoglycan solubilized by ultrasonic treatment gave precipitin reactions with hyperimmune antisera. By means of inhibition studies of the glucose-mannose polymer specificity, glucose appeared as the immunodominant sugar in the majority of antibodies studied. Inhibitions studies also confirmed that both the glycan and peptide moieties constitute antigenic determinants of M. lysodeikticus peptidoglycan. Antibodies to the glucose-mannose-polymer and the peptidoglycan were specifically fractionated by use of immunoadsorbents formed from lysozyme solubilized cell walls and activated Sepharose. Both antibody specificities showed a limited heterogeneity by isoelectric focusing. Finally, because antisera to M. lysodeikticus are a rich source of antibodies to peptidoglycan, emphasis is placed on the possible usefulness of this system for studies of clonal dominance.

Adsorption↗
PubMedDate not supplied

[Lipids and lipopolysaccharides of "Micrococcus radiodurans" (author's transl)].

Studies were carried out on lipid composition of Micrococcus radiodurans. The polar lipid components were found to be 4 glycolipids, 3 phospholipids and 2 phosphoglycolipids. The major fraction belongs to the last group. Correlation between these components and lipoteichoic acid was not observed. A lipid-polysaccharidic complex was isolated. It was not of this type.

Glycolipids↗