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PubMedDate not supplied

Production of gluconic acid using Micrococcus sp.: optimisation of carbon and nitrogen sources.

A process for production of gluconic acid from glucose by a Micrococcus sp. is described. More than 400 bacterial cultures isolated from local soil were tested for gluconic acid production. Three isolates, were selected on basis of their ability to produce gluconic acid and high titrable acidity. These were identified as Micrococcus sp. and were named M 27, M 54 and M 81. Nutritional and other parameters for maximum production of gluconic acid by the selected isolates were optimised. It was found that Micrococcus sp. isolate M 27 gave highest yield of 8.19 g gluconic acid from 9 g glucose utilised giving 91% conversion effeciency.

Carbon↗
PubMed1962

Induction of lysogenic Micrococcus lysodeikticus.

Field, A. K. (Cornell University, Ithaca, N.Y.) and H. B. Naylor. Induction of lysogenic Micrococcus lysodeikticus. J. Bacteriol. 84:1129-1133. 1962.-Between 50 and 60% of log-phase cells of Micrococcus lysodeikticus strain ML 53-40, lysogenic for N5 bacteriophage, were induced by an optimal dose of ultraviolet light. Induction of dilute cell suspensions caused a subsequent 200- to 800-fold increase in infective-center concentration. Cells in the stationary growth phase and cells adapted to a chemically defined medium were also induced by ultraviolet irradiation. Dimethyl sulfate induced the lysogenic culture to about the same extent as did ultraviolet light, whereas beta-propiolactone was less effective.

Bacteriophages↗
PubMed1964

ACRIDINE ORANGE BINDING BY MICROCOCCUS LYSODEIKTICUS.

Beers, Roland F., Jr. (Johns Hopkins University, Baltimore, Md). Acridine orange binding by Micrococcus lysodeikticus. J. Bacteriol. 88:1249-1256. 1964.-Micrococcus lysodeikticus cells bind acridine orange (AO) reversibly. The adsorption isotherm is consistent with a highly cooperative-type binding similar to that observed with polyadenylic acid. The cells exhibit a strong buffering action on the concentration of free AO which remains constant (1 mug/ml) over a range from 5 to 95% saturation of the cells by AO. The cells stain either fluorescent orange or green. The fraction stained orange is directly proportional to the quantity of dye adsorbed, indicating that these cells bind a fixed amount of AO (10% of dry weight). The green-stained cells contain less than 1% of the AO bound to orange-stained cells. The results suggest that the abrupt increase in amount of AO bound by the orange-stained cells occurs when the concentration of free AO reaches a threshold concentration. Similar results were obtained with Bacillus cereus. Mg increases the free AO concentration and the extent of binding capacity of the cells.

Acridine Orange↗
PubMed1965

NONPHOTOREACTIVATING REPAIR OF ULTRAVIOLET LIGHT-DAMAGED MICROCOCCUS LYSODEIKTICUS CELLS.

Elder, Robert L. (Johns Hopkins University, Baltimore, Md.), and Roland F. Beers, Jr. Nonphotoreactivating repair of ultraviolet light-damaged Micrococcus lysodeikticus cells. J. Bacteriol. 89:1225-1230. 1965.-Micrococcus lysodeikticus cells are highly resistant to ultraviolet radiation. The shape of the dose-survival curve is consistent with the presence of a repair mechanism. The presence of nontoxic doses of dinitrophenol (0.1 mm) or iodoacetate (1 mm) before or after radiation decreases the survival number and the initial lag in the dose-kill curve. The extent of decrease in survival after postradiation treatment with these compounds is dependent upon both time and temperature. Organisms that survive radiation show a prolonged lag phase before multiplying. No photoreactivation of the radiated cells can be demonstrated. Ultraviolet-radiated phage show a higher inactivation when plated on host cells of M. lysodeikticus treated with dinitrophenol at concentrations which do not affect the infectivity of nonradiated phage. The resistance of these cells to ultraviolet radiation is the result of a very efficient dark-cell repair mechanism that can be blocked by iodoacetate or dinitrophenol.

Bacteriophages↗
PubMed1981

Reduced transcription activity of rat liver chromatin after protein restriction and selective digestion of nuclei with micrococcus nuclease.

Restriction of protein intake in the diet has been shown to produce a change in transcription activity as determined in vitro. Conditions for a reduced transcription activity were investigated with selective digestion of nuclei with micrococcus nuclease (EC 3.1.4.7). Liver nuclei from young male rats fed a diet containing either 20 or 3% casein for 6 days were digested with 1.3 microgram of micrococcus nuclease protein/mg of nuclear DNA (specific enzyme activity 15,000 or 150 units/mg of protein). Part of the chromatin-bound RNA polymerase activity was transferred from the 2,000 x g to the 102,000 x g pellet. Independent of the type of endonuclease use, the specific activity of chromatin-bound and soluble RNA polymerase I plus III was similar in the two groups of rats. After protein restriction RNA polymerase II activity was significantly diminished in the 2,000 x g pellet, and was unchanged in the 102,000 x g pellet. Heparin-stimulated and soluble RNA polymerase II activities were significantly reduced. Number and length of RNA chains synthetized by chromatin-bound RNA polymerase I plus III remained unchanged by dietary treatment. After a low protein diet, RNA polymerase II in the absence and presence of heparin synthesized an unchanged number of RNA chains with reduced length. A selective digestion of chromatin with micrococcus nuclease is needed to show the reduction in RNA polymerase II activity after protein restriction.

Animals↗
PubMed1983

Biotypes of Staphylococcus epidermidis and Micrococcus organisms, isolated from intramammary infections, reclassified into species of the genus Staphylococcus (epidermidis, hyicus, xylosus, and sciuri).

In a previous report (5), strains of Staphylococcus epidermidis and Micrococcus isolated from bovine intramammary infections were classified by the Baird-Parker (B-P) system and by serologic typing of the proteolytic enzymes. Since then, newer methods for distinguishing the genera Staphylococcus and Micrococcus and for defining new species have been reported. By utilizing these methods, the organisms from the original study were reclassified as follows: S. epidermidis B-P subgroup II, proteinase group F strains as S. epidermidis; S. epidermidis B-P subgroup III, proteinase group B strains as Staphylococcus hyicus subsp. chromogenes (pigmented) or subsp. hyicus (nonpigmented) and proteinase groups H and BH strains that were coagulase positive and nonpigmented as subsp. hyicus; B-P Micrococcus subgroup 6, proteinase group NR strains as Staphylococcus xylosus and subgroup 6, proteinase group G strains as Staphylococcus sciuri and S. xylosus. The reclassification of the strains increased the percentage of intramammary infections attributed to staphylococci from 62%, as first reported, to at least 86%.

Animals↗
PubMed1997

Relationship between antibacterial activity and cell surface binding of lactoferrin in species of genus Micrococcus.

Human lactoferrin was bactericidal in vitro for Micrococcus luteus but not for other Micrococcus species (M. radiophilus, M. roseus and M. varians). A correlation between the binding of lactoferrin to the bacterial surface and the antimicrobial action was observed. Viability assays showed that ferric, but not ferrous, salts prevented binding and consequently M. luteus was not killed. The unsaturated form of lactoferrin showed a greater affinity than that of the iron-saturated molecule for lipomannan, a lipoglycan present on the cell wall of M. luteus, supporting the role for lipomannan as one of the possible binding sites of lactoferrin on M. luteus.

Anti-Bacterial Agents↗
PubMed1963

Degradation of pyruvate by Micrococcus lactilyticus. III. Properties and cofactor requirements of the carbon dioxide-exchange reaction.

Whiteley, H. R. (University of Washington, Seattle) and N. G. McCormick. Degradation of pyruvate by Micrococcus lactilyticus. III. Properties and cofactor requirements of the carbon dioxide-exchange reaction. J. Bacteriol. 85:382-393. 1963.-At an acid pH, extracts of Micrococcus lactilyticus (Veillonella alcalescens) catalyze the oxidative decarboxylation of pyruvate to carbon dioxide, hydrogen, and acetyl phosphate, and the rapid exchange of carbon dioxide into the carboxyl group of pyruvate. These reactions take place only under anaerobic conditions and require phosphate (or arsenate), a reducing agent, diphosphothiamine, coenzyme A, an electron acceptor (ferredoxin, flavins, dyes, or certain inorganic anions), and a divalent cation (Co(++)> Mn(++) > Mg(++) > Fe(++)). High concentrations of coenzyme A and electron acceptors stimulate pyruvate breakdown but inhibit CO(2) exchange. Exchange is also inhibited by p-chloromercuribenzoate but not by arsenite. Extracts rapidly lose the ability to mediate the exchange reaction after passage through diethylaminoethyl- or triethylaminoethyl-cellulose or Dowex-1; this loss in activity may be prevented by adding a reducing agent and the above cofactors. The exchange of CO(2) and formate by M. lactilyticus is compared.

Carbon Dioxide↗
PubMed1964

ORIGIN OF PALMITIC ACID CARBON IN PALMITATES FORMED FROM HEXADECANE-1-C-14 AND TETRADECANE-1-C-14 BY MICROCOCCUS CERIFICANS.

Finnerty, W. R. (University of Iowa, Iowa City), and R. E. Kallio. Origin of palmitic acid carbon in palmitates formed from hexadecane-1-C(14) and tetradecane-1-C(14) by Micrococcus cerificans. J. Bacteriol. 87:1261-1265. 1964.-Degradation of the palmitic acid moiety of cetyl palmitate and myristyl palmitate formed from hexadecane-1-C(14) and tetradecane-1-C(14) by Micrococcus cerificans was carried out. The patterns of C(14) labeling in palmitic acid from cetyl palmitate showed that hexadecane is oxidized at the C(1) position, and cetyl alcohol and palmitic acid thus formed are directly esterified. Palmitic acid arising from tetradecane and esterified to tetradecanol appeared to have been synthesized by the addition of two carbon atoms to an existing 14-carbon atom skeleton. Considerable mixing of C(14) occurred in the C(1) and C(2) positions of palmitic acid thus synthesized.

Alkanes↗
PubMed1987

Pitted keratolysis. The role of Micrococcus sedentarius.

Though pitted keratolysis of the foot is generally viewed to be caused by bacteria, there is confusion regarding the identity of the causative organism. Species of Corynebacterium, Actinomyces, Dermatophilus, and Micrococcus have been proposed by various investigators. We have studied eight cases of pitted keratolysis and have cultured an organism identified as Micrococcus sedentarius on the basis of colonial morphology, micromorphology, biochemical reactions, and chemical analysis of whole-cell components. Furthermore, pitted keratolysis was produced experimentally in a human volunteer by applying M sedentarius under an occlusive dressing onto the surface of the heel.

Bacteriological Techniques↗
PubMed2003

Fourier transform IR spectroscopic appraisal of radiation damage in Micrococcus luteus.

Fourier transform IR spectroscopy (FTIR) is used to analyze cells of Micrococcus luteus, the type species of the highly heterogeneous genus Micrococcus that belongs to the Micrococcaceae family. The cells of M. luteus, which is a Gram-positive and yellow-pigmented bacterium, are submitted to increasing doses of gamma radiation. Irradiation leads to the generation of reactive oxygen species that induce biochemical changes as shown in spectral profiles. Beyond a dose of 0.70 kGy, significant differences between samples are observed, particularly in the 1485-900 cm(-1) region, which contains information about membrane lipids, cell wall polysaccharides, and nucleic acids. After a dose of 16.50 kGy, M. luteus is reincubated for times ranging from 1 to 24 h. Postirradiation reincubated bacteria are found far from the control and irradiated cells (mainly in the 985-900 cm(-1) range), suggesting that a biomolecular rearrangement occurs as soon as reincubation begins in the growth medium. Thus, FTIR spectroscopy appears to be a very useful technique for the rapid visualization of the alterations induced by both the radiation and mutagenic response during reincubation. The use of mathematical methods gives good insight into the biomolecular compounds involved in these two mechanisms. In view of these preliminary results, we hypothesize that it can be successfully applied to any type of tissue and that it may be a future interesting tool for evaluating the effects of radiation in humans.

DNA Damage↗
PubMed1995

Secretion of an antibacterial factor during resuscitation of dormant cells in Micrococcus luteus cultures held in an extended stationary phase.

A high proportion of Micrococcus luteus cells in cultures starved for 3-6 months in spent medium following growth to stationary phase in batch culture lost the ability to grow and form colonies on agar plates, but could be resuscitated from dormancy by incubation in liquid medium containing supernatant taken from the late log phase of viable cultures of the same organism (Kaprelyants et al. 1994). In the present work, we found that during the first 50-70 h of such resuscitation the dormant cells actually divide for 10-17 generations in lactate minimal medium containing yeast extract whilst remaining nonculturable on agar plates. Further incubation results in a decrease in the total cell number in liquid medium. The addition of viable (culturable) Micrococcus luteus cells in concentrations of up to 10(4) ml-1 to test tubes containing either resuscitating cells or supernatant from these cultures revealed the excretion of a factor or factors which inhibited the proliferation of otherwise viable cells. The maximum production of this factor took place after some 96 h of incubation of starved cells in resuscitation medium. Supernatant from late logarithmic phase batch cultures of M. luteus abolished the antibacterial effect of starved cultures incubated in resuscitation medium. It is concluded that the stimulating effect of viable cells, and of supernatant taken from batch cultures, on the resuscitation of dormant cells might be connected in part with overcoming the activity of an antibacterial factor causing self-poisoning of dormant cells during their resuscitation.

Anti-Bacterial Agents↗
PubMed1991

Identification of Staphylococcus and Micrococcus species with the STAPHYtest system.

A collection of 216 well-characterized strains of Staphylococcus, Micrococcus and Stomatococcus was examined by a commercially available STAPHYtest system (Lachema, Brno, Czechoslovakia). The results of STAPHYtest agreed with those of conventional tests. The STAPHYtest permitted a clear-cut separation of Staphylococcus from Micrococcus and Stomatococcus strains and correctly identified 104 of 145 (72%) Staphylococcus strains after 24 h of incubation. However, it allowed the identification only of 19 of 29 validly published Staphylococcus species. The STAPHYtest proved to be a simple and rapid system for the separation of staphylococci from micrococci and for the identification of most frequent clinically significant staphylococci.

Bacteriological Techniques↗
PubMed1975

Induction of nutritional mutants of Micrococcus glutamicus and their amino acid accumulation.

Micrococcus glutamicus ATCC 13032, a glutamic acid-producing organism, was treated with 0.2M ethylmethane sulfonate, the auxotrophs isolated showing varied patterns of extracellular amino acids. Eighty auxotrophic strains were obtained, out of which 31 excreted 1.0-4.0 mg threonine per ml and all the auxotrophs required biotin for growth and production of the amino acid. Eleven auxotrophs produced 1.5 to 3.0 mg alanine per ml and these auxotrophs required amino acids for their growth. Other auxotrophs lost their excretion capacity in subsequent fermentation trials. Further mutation of the biotin-requiring auxotroph Micrococcus glutamicus EM with gamma rays resulted in the isolation of 89 auxotrophic strains, out of which 28 excreted threonine (up to 5.0 mg per ml) higher than the parent auxotroph. Exposure to X-rays yielded 97 auxotrophs, out of these 35 producing 1.0-3.0 mg methionine per ml and requiring biotin for growth and production of the amino acid. Other auxotrophs produced alanine (0.5 to 2.0 mg per ml) and threonine (2.0 to 3.3 mg per ml). Irradiation with gamma rays favoured the development of threonine producing auxotrophs while X-rays favoured methionine-producing auxotrophs.

Alanine↗
PubMed1988

Elimination of mercury, cadmium and antibiotic resistance from Acinetobacter lwoffi and Micrococcus sp. at high temperature.

Resistance determinants for HgCl2 and CdCl2 were eliminated along with a number of antibiotic resistance factors from Acinetobacter lwoffi and Micrococcus sp. at 44 degrees C. These organisms were orginally resistant to HgCl2, merbromin, CdCl2, Pb(NO3)2, benzylpenicillin, erythromycin, carbenicillin, tetracycline and sulfadiazine. Four different types of mutants from A. lwoffi (type I to IV) and one type of mutant from Micrococcus sp. (type V) were obtained, depending on the loss of particular resistance factors for HgCl2, merbromin, CdCl2 and antibiotics. In general, frequency of elimination of all the missing markers was very low (in the range of 10(-3) per bacterium). However, the missing determinants did not revert spontaneously.

Acinetobacter↗
PubMed1975

Induction of mutation to streptomycin resistance in Micrococcus radiodurans.

No detectable induction of mutation to streptomycin resistance could be used in wild-type Micrococcus radiodurans and its radiation-sensitive and super-resistant mutants by ionizing or UV-radiation. N-methyl-N'-nito-N-nitrosoguanidine (NTG) was mutagenically active. The results suggest that repair of radiation-damaged DNA in Micrococcus radiodurans is mutation-proof.

Cobalt Radioisotopes↗
PubMed1994

Proteolytic and lipolytic activities of Micrococcus roseus (65), Halomonas elongata (16) and Vibrio sp. (168) isolated from Danish bacon curing brines.

Viable cells, cell free extracts and extracellular concentrates of Micrococcus roseus (65), Halomonas elongata (16) and Vibrio sp. (168) isolated from Danish bacon curing brines were examined for lipase, esterase, proteinase and aminopeptidase activities on natural and synthetic substrates. Micrococcus roseus (65) produced one intracellular esterase with affinity for short chain esters, and two intracellular aminopeptidases with affinity for nonpolar amino acids and L-arginine, respectively. One extracellular aminopeptidase with affinity for L-proline was also observed. Three intracellular esterases with affinity for short chain esters and a membrane bound esterase with affinity for butyric to capric esters were found in Halomonas elongata (16), but almost no aminopeptidase activity was found. Vibrio sp. (168) had four intracellular esterases with affinity for short chain esters and one esterase with affinity for all tested esters. Furthermore, an enzyme, which did not migrate on electrophoretic gels, had activity on all examined esters and tributyrin. Small intracellular activity on L-alanine was observed for this bacterial strain. There was no proteinase activities in the tested bacteria.

Aminopeptidases↗
PubMed1990

Micrococcus and Stomatococcus spp. from human infections.

Infections with Micrococcus spp. in six patients and Stomatococcus mucilaginosus in one patient are described. Two of the Micrococcus infections occurred in leukaemic patients with indwelling lines, six episodes occurred in three patients undergoing continuous ambulatory peritoneal dialysis and one occurred in a patient with a ventriculo-peritoneal shunt. Stomatococcus was isolated from fluid draining from a sub-dural haematoma. Colony morphology, oxidase reaction and resistance to nitrofuration were useful in differentiation of micrococci from staphylococci. Incidence and risk factors for micrococcal infections appear similar to those for infections with coagulase-negative staphylococci (CNS), but the literature is confused due to changes in the definitions of these genera.

Adolescent↗