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PubMed1975

The characterization of mannan of Micrococcus lysodeikticus as an acidic lipopolysaccharide.

Ghosts of Micrococcus lysodeikticus contain a mannan that is not removed by intensive washing procedures. Purified mannan, isolated by extraction of whole cells with hot, aqueous phenol, binds to membranes in vitro. Mannan also binds to DEAE-cellulose and migrates toward the anode in neutral and sodium dodecyl sulfate disc gel electrophoresis. In aqueous solution mannan has an apparent molecular weight of 10-6, but in the presence of sodium dodecyl sulfate its apparent molecular weight is 50,000 to 100,000; removal of the detergent results in reaggregation. Purified mannan contains mannose, succinate, fatty acid, and glycerol in a ratio of 50:4.9:2.1:1.0. Treatment of mannan with mild base produces a neutral, hydrophilic polysaccharide of relatively low molecular weight that has no affinity for membranes. At least 90% of the reducing termini are blocked in a base-stable linkage. Based on these results a tentative structure is proposed for the mannan.

Binding Sites↗
PubMed2000

Micrococcus luteus: a putative cause of hepatic abscess?

Micrococcus luteus was repeatedly isolated in blood cultures during a prolonged feverish syndrome in a patient who presented with multiple hepatic abscesses as well. In contrast to the literature, this case is not related to prosthetic devices; an untreated limb wound may have been the site of microbial entry.

Gram-Positive Bacterial Infections↗
PubMed2001

PCR cloning of the resuscitation-promoting factor (Rpf) gene from Micrococcus luteus, sequencing and expression in Escherichia coli.

A polymerase chain reaction (PCR) cloning procedure was developed for the resuscitation-promoting factor (Rpf) gene of Micrococcus luteus using strains NCIMB 13267, JCM 1464T, JCM 3347, and JCM 3348. A PCR product of the Rpf gene fragment was ligated into a cloning vector pBluescript II KS (+) with the restriction endonucleases Eco RI and Bam HI. The ligation mixture was used to transform Escherichia coli DH5alpha. The DNA sequence of the Rpf gene cloned from strain JCM 1464T was 84% homologous with that of NCIMB 13267, and from strains JCM 3347 and JCM 3348 it was 100% and 86% homologous, respectively. Recombinant Rpf proteins of M. luteus NCIMB 13267 and JCM 1464T after expression in E. coli BL21 harbouring the pET-19b-Rpf plasmid, and after purification, were approximately 16 kD for both strains.

Amino Acid Sequence↗
PubMed1975

Knee joint infections with Staphylococcus aureus and Micrococcus species.

In rabbit knees 600 Staphylococcus aureus organisms produced progressive infection in 50 per cent of the knees injected, whereas 5.3 times 10-7 Micrococcus species caused only transient colonization of the joints. Methicillin, cephacetrile, and clindamycin administered before injection of the staphylococci gave protection. Stainless-steel particles in the knee did not increase susceptibility to infection from injected micrococci but did make established micrococcal infections more persistent. Knees containing steel debris failed to become infected during prolonged staphylococcal bacteremia. Injected autologous blood, either fresh or three days old, did not increase susceptibility to infection. Large doses of steroids, given systemically or intraarticularly, decreased resistance to micrococcal infection and increased the destruction caused by infection due to this organism.

Animals↗
PubMed2001

Bioconversion of 1,3 dinitrobenzene by Micrococcus colpogenes strain MCM B410: quantitation and characterization of the intermediates.

Micrococcus colpogenes MCM B 410, indigenous to soil, collected from nitro aromatic contaminated site, could transform 1,3 dinitrobenzene (m-DNB) initially to m-nitroaniline, m-nitrophenol, m-aminophenol and resorcinol at 30 degrees C under shake culture condition. Carbon mineralization studies with unlabelled and radio labelled 1,3 (U14 C) dinitrobenzene subtrates indicated that the above metabolities appeared within 4 days. After 7 days incubation a significant traction of the source compound was degraded to C Q through aliphatic acids. Presence of nitro aryl reductase, aryl monooxygenase and resorcinol 1,3 di oxygenase was also noted in the sonicated cell mass.

Carbon↗
PubMedDate not supplied

[Effect of levomycetin (chloramphenicol) on the biosynthesis of membrane proteins, structure and some functions of Micrococcus lysodeikticus bacterial membranes].

Levomycetin (chloroamphenicol), an inhibitor of protein synthesis, caused drastic changes in the molecular organization of bacterial membranes being introduced into the cultural medium of Micrococcus lysodeikiticus (50-100 mkg/ml. Isolated membranes of levomycetin-treated cells are enriched with lipids as compared with the control, they are more labile and they lose the X protein component and a considerable part of dehydrogenases, which results in the significant inhibition of all the respiration chain. At the same time the content of cytochrome alpha was increased by 17%, and the activity of malate dehydrogenase (as estimated in cell lysates) was two-fold increased in levomycetin-treated cell as compared with the control. It means that biosynthesis of some membrane proteins can be twice more resistant to the action of the antibiotic than the biosynthesis of other proteins, the total protein biosynthesis being significantly depressed (the incorporation of labelled leucine in membrane proteins is inhibited by 78%, and in cytoplasmic proteins-by 83%). The ratio of the respiration rate of intact levomycetin-treated cells to the protein content or to the cell bulk was similar to that of the control culture, which testifies the stability of membranes in vivo even under considerable "fattening". The loss of dehydrogenases and the X protein from the membranes apparently takes place at the moment of the cell rupture during the lysis in hypotonic medium. The ratio of the respiration rate of intact levomycetin-treated cells to the content of cytochromes a, b, c was 1.15-1.55 times as low as that of control cells which is probably due to the tendency of respiration components to the independent translocation in the membrane and is the result of the decrease in the concentration of the respiration components under the less than fattening greater than of the membrane.

Bacterial Proteins↗
PubMedDate not supplied

[Lipid synthesis by Micrococcus freudenreichii in media containing unsaturated hydrocarbon's].

The growth and synthesis of lipids by thermotolerant bacteria Micrococcus freudenreichii K-219 were investigated in the mineral medium containing a mixture of unsaturated (I-) and saturated hydrocarbons. The bacteria utilized primarily I-alkenes. In lipids the predominant fractions were phospholipids (57%) and free fatty acids (20%). The content of waxes which were in significant quantities in n-alkane containing media (9%) was not higher than 0.3% dry matter upon utilization of I-alkenes. There was a certain correlation between carbon atoms of synthesized fatty acids and unsaturated hydrocarbons used. Bacteria utilizing I-alkenes showed no elevated unsaturation of cell lipids as compared to those assimilating n-alkanes. These data give evidence for different pathways of oxidation of alkenes and alkanes by the above microbial strain.

Alkanes↗
PubMedDate not supplied

[Regulation of lysine biosynthesis in the leucine-dependent mutant of Micrococcus glutamicus].

The role of leucine in metabolism of Micrococcus glutamicus was examined in relation to the lysis synthesis by the homoserine- and leucine-dependent strains of M. glutamicus 106 and the homoserine-dependent strain of M. glutamicus 95. In addition to the growth function, leucine produced a controlling effect on the yield of the end product. In the presence of leucine the inhibitory effect of isoleucine on the lysine yield was reduced or reversed. The end effect depended on the leucine: isoleucine ratio. The mechanism of interaction of amino acid metabolites with respect to the lysine biosynthesis in both strains is discussed.

Homoserine↗
PubMedDate not supplied

Menaquinone function in the respiratory chain of Micrococcus lysodeikticus.

Menaquinone-9 which is destructed under long-wave UV-irradiation is isolated from Micrococcus lysodeikticus membranes. NAD-H, malate and lactate oxidases are observed to be inhibited under irradiation, dehydrogenases of these substrates being almost intact. Photoinactivation of menaquinone results in the reduction of only one from two cytochromes b, presented in the membrane, thus testifying the location of menaquinone-9 between cytochromes b in the respiratory chain. Reconstruction of malate, NAD-H and lactate oxidases after irradiation took place when natural menaquinone (MQ-9) or menadione (MQ-0) were added. Detailed scheme of M. lysodeikticus respiratory chain is given.

Cell Membrane↗
PubMed1975

Classification of the bacteriophages of Gram-positive cocci: Micrococcus, Staphylococcus, and Streptococcus.

Micrococcus, Staphylococcus, and Streptococcus phages are classified by morphology, serological properties and physical and chemical parameters of the virion and its nucleic acid. Fourteen species are defined; they include 75 tailed phages belonging to 6 morphological groups. Type species are proposed. Three species seem to have phylogenetic relationships with Bacillus phages.

Bacteriophage Typing↗
PubMed1975

Rheumatoid factor appearance in Micrococcus lysodeikticus immunization and its interference with allotype specific reactions.

Rabbits hyperimmunized with Micrococcus lysodeikticus produce, in addition to anti-cell wall antibodies, considerable amounts of anti-immunoglobulins or rheumatoid factors which can interfere with immune reactions. In particular, in immunodiffusion, they can reveal non precipitating systems for which the immunodiffusion typing sera are usually not tested. In our hands, rabbit allotypes d12 and A8 give rise to visible immunodiffusion reactions in presence of rheumatoid factors. Inhibition of this reaction can be used to type for these markers in sera which do not contain the rheumatoid factors.

Antibodies, Bacterial↗
PubMed2003

[Occurrence and number of bacteria from the Micrococcus, Kocuria, Nesterenkonia, Kytococcus and Dermacoccus genera on skin and mucous membranes in humans].

The aim of work was to evaluate the frequency of occurrence of bacteria from genera of Micrococcus, Kocuria, Nesterenkonia, kytococcus and Dermatococcus on human skin and mucous membranes in healthy population. Among 150 investigated persons these bacteria were found in 122 (81.3%). The frequency of isolation was similar in both sex (82.4% in female and 79.7% in male). Most often the strains were isolated from oral cavity (48.7%), and from skin of palm and forearm (40.7% and 37.3%). Least frequency of occurrence was observed in vestibule of nose (26%). The predominant isolated strains were: M. luteus (26.2%), and N. halobia (21%) followed by K. varians (16.4%), M. lylae (12.2%), D. sedentarius (9.1%), K. kristinae (7.3%), K. nishinomiyaensis (7.3%), K. rosea (0.3%).

Actinomycetales↗
PubMed1977

[Osmotic activity and ionic permeability of membrane vesicles from Streptococcus faecalis and Micrococcus lysodeikticus cells].

Membrane fractions containing osmotically active vesicles with sufficiently low membrane permeability for K+, Na+ and Cl- ions typical for the intact cell membrane were isolated from the cells of the glycolyzing bacterium Streptococcus faecalis. In their osmotic properties and ionic permeability the membrane fractions of S. faecalis were found similar to those of the respiring bacterium Micrococcus lysodeikticus, which are capable of the energy-dependent potassium transport. It may be thus assumed that the S. faecalis fractions obtained may be used to study ionic transport. The removal of proton-dependent ATPase of the S. faecalis membrane preparations did not affect the permeability of membranes for K+ ions which is indicative of different mechanisms of proton and potassium translocation.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Protein synthesis with cell extracts of Micrococcus radiodurans (author's transl)].

Pure active ribosomes of cells of Micrococcus radiodurans could be obtained when cultivated in trypton, glucose and nutrient broth by adding natrium citrate. The optimal conditions for a cell-free protein synthesis were investigated at the (polyuridylic acid) dependent polyphenylalanine synthesis. When exchanging ribosomes and S100-fractions with the corresponding fractions of E. coli, we found that the enzyme fractions of M. radiodurans extremely inhibit the ribosomal activity. The incorporation rates in the cell-free system of M. radiodurans yield, at comparable conditions, in relation to E. coli under 10%.

Bacterial Proteins↗
PubMedDate not supplied

[The role of alkylhydroxybenzenes in the adaptation of Micrococcus luteus to heat shock].

The response of the gram-positive bacterium Micrococcus luteus to heat shock (45 degrees C, 15 min) and the adaptogenic activity of alkylhydroxybenzenes (AHB), which are extracellular growth-regulating substances of these bacteria, were studied. The perception of stress and the postshock behavior of M. luteus cells proved to depend on the growth phase and medium. The magnitude of stress response was more pronounced in cultures grown on synthetic medium than in cultures grown on rich medium (nutrient broth). During exponential or linear growth, the cells were more sensitive to the temperature effect than during decelerated growth. In linearly growing M. luteus cultures, the amount of total intra- and extracellular alkylhydroxybenzenes, the anabiosis inducers, increased in response to heat shock. AHB redistribution between cells and culture liquid occurred in the course of stress and after stress. In micrococci exposed to heat shock, an increase in the AHB concentration both in cells and culture liquid is likely a defense reaction of stress resistance. This conclusion was confirmed in the experiments with the addition 30 min before the heat shock of a chemical analogue of the anabiosis inducer, C7-AHB (12 mM), which protected M. luteus cells so that their intense growth was observed after shock without any lag. The protective effect of AHB is a result of their ability to form complexes with enzyme macromolecules and stabilize them. The data obtained extend the knowledge of the stress-protective functions of low-molecular-weight autoregulators and of the role of intercellular communications in the stress response of bacterial cultures.

Adaptation, Physiological↗
PubMed1979

[gamma-Irradiated ribosomes from Micrococcus radiodurans in a cell-free protein synthesizing system (author's transl)].

gamma-irradiation inactivation of isolated ribosomes of Micrococcus radiodurans was studied by examining poly U directed synthesis of polyphenylalanine. Ribosomes of M. radiodurans did not show significant gamma-radiation sensitivity up to a dose of approx. 11.6 k Gy. Cells of M. radiodurans take up more magnesium than E. coli cells unter the same conditions. The magnesium content of ribosomes of M. radiodurans was 18% higher than that of E. coli ribosomes. A possible relation between Mg2+-content and gamma-resistance is discussed.

Dose-Response Relationship, Radiation↗
PubMed1992

Structure of a Micrococcus lysodeikticus cell wall fragment containing phosphorylated sugars.

A polysaccharide-peptidoglycan complex containing different phosphorylated sugars from Micrococcus lysodeikticus cell wall has been isolated and purified. The peptidoglycan contained muramic acid 6-phosphate and N-acetylglucosamine 6-phosphate as phosphorylated sugars in addition to other sugar residues. Mild acid hydrolysis of the peptidoglycan and subsequent reduction of the released polysaccharide showed therein the presence of glucose and N-acetyl-glucosamine in the linkage of the external polysaccharide residues to the peptidoglycan through phosphodiester linkage. These data suggest the presence of polysaccharide chains linked to a peptidoglycan core through two phosphorylated sugars via two different terminal carbohydrate residues of the external polysaccharide chains in a same polymer.

Carbohydrate Sequence↗
PubMedDate not supplied

[Cell aggregation in cultures of Micrococcus luteus studied by dynamic light scattering].

Cell aggregation was studied using the method of dynamic light scattering in the course of growth of Micrococcus luteus cultures in a liquid medium. The method detects particles ranging in size from 0.5 to 1000 microm in samples containing no more than 10(5) cells/ml. When grown in liquid media, M. luteus forms aggregates; during the lag phase, 80% of the cells are found in aggregates of 10 to 1000 microm, only minor amounts being represented by single cells. With the onset of exponential growth, the aggregates were decomposed, and single cells became prevalent in the culture liquid. This observation confirms that the aggregation of the cells during the lag phase is prerequisite to the initiation of bacterial growth. The method may be used in biotechnology for monitoring the state of bacterial cultures.

Culture Media↗