• Title/Summary/Keyword: Micrococcus luteus

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Characteristics of Algicide Produced by Micrococcus luteus SY-13 Inhibiting Cochlodinium polykrikoides and the Effects on Marine Organisms (적조생물 Cochlodinium polykrikoides를 저해하는 Micrococcus luteus SY-13이 생산하는 살조물질의 특성과 해양생물에 미치는 영향)

  • Kim, Min-Ju;Jeong, Seong-Yun;Cha, Mi-Sun;Lee, Sang-Joon
    • Journal of Environmental Science International
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    • v.17 no.4
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    • pp.439-449
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    • 2008
  • Algicidal bacterium was isolated from sea water during the declining period of Cochlodinium polykrikoides blooms and this bacterium had a significant algicidal activity against C. polykrikoides. In this study, algicidal bacterium was identified on the basis of biochemical and chemotaxonomic characteristics, and analysis of 16S rDNA sequences. The algicidal bacterium showed 98.6% homology with Micrococcus luteus ATCC $381^T$. Therefore, this bacterium was designated Micrococcus luteus SY-13. The optimal culture conditions of the algicidal bacterium was $25^{\circ}C$, initial pH 8.0, and 3.0% NaCl concentration. M. luteus SY-13 is assumed to produce secondary metabolites which have algicidal activity. When 10% culture filtrate of this strain was applied to C. polykrikoides ($1.0\;{\times}\;10^4\;cells/ml$) cultures, over 98% of C, polykrikoides cells were destroyed within 6 hours. The culture filtrate of M. luteus SY-13 exhibited similar algicidal activity after heat-treatment at $121^{\circ}C$ for 15 min. While algicidal activity remained in filtrates with pH adjusted to 8.0, loss of algicidal activity occurred when the pHs of filtrates were adjusted to over 9.0 or heat-treated at $121{\times}180^{\circ}C$ for 1 hour. M. luteus SY-13 showed significant algicidal activities against C. polykrikoides (98.9%) and a wide algicidal range against various harmful algal bloom (HAB) species. However, there was no algicidal effect on diatom and marine livefood organisms except Isocrysis galbana. These results suggest that M. luteus SY-13 could be a candidate for use in the control of HABs.

Characteristics of a Mutant of Trehalose-producing Micrococcus luteus and Optimization of Production Conditions (Trehalose를 생산하는 Micrococcus luteus 변이주의 특성 및 생산배지의 최적화)

  • 송희상;황기철;방원기
    • Microbiology and Biotechnology Letters
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    • v.27 no.5
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    • pp.399-403
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    • 1999
  • For the production of trehalose, microorganisms capable of producing trehalose extracellularly were screened from the stock cultures in our laboratory. among them, Micrococcus luteus IFO 12708 showed the highest productivity of trehalose. For the increase of productivity, the mutant strai Hs-208 having higher trehalose production was selected with NTG(N-methyl-N'-nitrosoguanidine) mutagenesis, which led to the decrease of the specific activity of trehalose phosphorylase(3.2-fold) as compared to the wild strain. The optimum condition for the trehalose production was established as follows: 20g/l of glucose and 6g/l of tryptone were used as a sole carbon source and nitrogen source, respectively, and cultivations were carried out at 3$0^{\circ}C$ and pH 6.0. After 20hrs cultivation, addition of 20unit/ml penicillin G led to the higher conversion yield of trehalose. Under the optimum condition, 6.547g/l trehalose was produced with conversion yield of 32.7%.

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Antibacterial Activity of Poncirus trifoliata Juice against Pathogenic Bacteria (병원성 세균에 대한 탱자즙의 항균효과)

  • 이영근;차인호
    • Journal of Life Science
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    • v.11 no.6
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    • pp.554-560
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    • 2001
  • For development of functional food, antibacterial effect of Poncirus trifoliata juice was examined. Strong antibacterial activities of Poncirus trifoliata juice were observed aginst Gram positive and negative pathogenic bacteria such as Baillus cereus, Bacillus subtilis, Corynebacterium zerosis, Listeria monocytogenes, Micrococcus luteus, Rhodococcus equi, Klebsiella pneumoniae, Pseudomonas aeruginosa, Vibrio alginolyticus, Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vnlnificus and Yersinia enterocolitica. The minimum inhibitory concentration(MIC) of Poncirus trifoliata juice against Bacillus cereus. Listeria monocytogenes, Micrococcus luteus, Rhodococcus equi, Staphylococcus epidermidis, Citrobacter freundil and Pseudomonas aeruginosa was 2.5% and the MIC against Vibrio cholerae, Vibrio parahemolyticus, Vibrio vulnificus and Yersinia enterocolitica was 1.25%. Also, antibacterial activities of Poncirus trifoliata juice treated for 15 min at 121$^{\circ}C$ were confirmed to be stable.

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Purification and Characterization of Purine Nucleoside Phosphorylase (PNP) in Micrococcus luteus

  • Choi, Hey-Seon
    • Journal of Microbiology
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    • v.34 no.1
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    • pp.82-89
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    • 1996
  • Purine nucleoside phosphorylase (PNP) was purified in Micrococcus luteus (M. luteus) using streptomycin sulfate and amomonium sulfate fractionation, three times by a Sephadex G-100 gel filtration and a DEAE-Sephadex A-50 ion exchange chromatography. The enzyme was purified 72 folds with a 11% recovery and showed a single band in a nondenaturing gel electrophoresis. The M. W. of PNP turned out to be 1.35 * 10$^{5}$ delton in G-150 gel filtration chromatography. The stability of the enzyme was increased by treatment with both substrates, MgCI$_{2}$ or CaCI$_{2}$, but not significantly kcal/mol. M. luteus PNP catalyzed the phosphorolysis of inosine, deoxyinosine, guanosine and deoxyguanosine with the Km value of 1.5 * 10$^{-3}$ M, 3.0 * 10$^{-3}$ M, 5.0 * 10$^{-4}$ M, respectively. The enzyme was reacted with adenosine, 1-methylnosine and 1-methylguanosine as substrates, which were shown to be poor substrates for mammalian enzyme.

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Catalytic mechanism and inhibition studies of purine nucleoside phosphorylase (PNP) in micrococcus luteus

  • Choi, Hye-Seon
    • Journal of Microbiology
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    • v.35 no.1
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    • pp.15-20
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    • 1997
  • Kinetic studies were done to elucidate the reaction mechanism of purine nucleoside phosphorylase (PNP) in Micrococcus Luteus. PNP catalyzes the reversible phosphorolysis of ribonucleosides to their respective base. The effect of alternative competing substrates suggested that a single enzyme was involved in binding to the active site for all purine nucleosides, inosine, deoxyiosine, guanosine, deoxyguanosine, adenosine and deoxyadenosine. Affinity studies showed that pentose moiety reduced the binding capacity and methylation of ring N-1 of inosine and guanosine had little effect on binding to bacterial enzyme, whereas these compounds did not bind to the mammalian enzymes. The initial velocity and product inhibition studies demonstrated that the predominant mechanism of reaction was an ordered bi, bi reaction. The nucleoside bound to the enzyme first, followed by phosphate. Ribose 1-phosphate was the first product to leave, followed by base.

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Characterization of Isocitrate Lyase from Micrococcus luteus (Micrococcus luteus에서 정제한 Isocitrate Lyase의 특성)

  • 정기택;서승교;우철주;박임동;정병태;박영호
    • Korean Journal of Microbiology
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    • v.31 no.3
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    • pp.230-236
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    • 1993
  • The isocitrate lyase extracted from Micrococcus luteus was purified 38.8 folds with the overall yield of 10.2%, by the ammonium sulfate fractionation, DEAE-cellulose, 1st Sephadex G-200 and 2nd Sephadex G-200 column chromatography. The purified enzyme showed to be a single protein band by polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was estimated 60,000 by the SDS-polyacry]amide gel electrophoresis. The apparent Michaelis constant, Km value for isocitrate was 0.95 mM. The optimum pH and temperature of the purified enzyme were pH 7.5 and $40^{\circ}C$, respectively. The enzyme was activated by $Mg^{2+}$ and inhibited by $Mn^{2+}$, $Ca^{2+}$, $Cu^{2+}$, $Zn^{2+}$ and $CO^{2+}$. In addition, the activity of isocitrate lyase was increased by glutathione and 2-mercaptocthanol at 5 mM and cysteine at I mM.

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Synthesis and Antimicrobial Activity of Polyacryloylcephalexine and Polymethacryloylcephalexine (Polyacryloylcephalexine과 Polymethacryloylcephalexine의 합성 및 그 항균작용)

  • Euy Kyung Yu;Gwon, Gyu Hyeok;Wol Suk Cha;Jae-Woon Na
    • Journal of the Korean Chemical Society
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    • v.37 no.7
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    • pp.677-682
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    • 1993
  • Polyacryloylcephalexine and polymethacryloylcephalexine were prepared by the reaction of polyacryloylchloride or polymethacryloyl chloride with cephalexine. The antimicrobial activities of these polymeric drugs were investigated by the common twofold dilution technique and the minimum inhibitory concentration (MIC) of polymeric durgs was also examined. Polyacryloylcephalexine revealed an excellent antibacterial activity against Micrococcus luteus ATCC 9341, Escherichia coli ESS, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, Mycobacterium phlei IFO 3158, Klebsiella pueumouiae KCTC 1560, Escherichia coli KCTC 1039, Salmonella typhimurium KCTC 1925. Polymethacryloylcephalexine revealed an excellent antibacterial activity against Micrococcus luteus ATCC 9341, Klebsiella pueumouiae KCTC 1560, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 25923, Mycobacterium phlei IFO 3158, Escherichia coli KCTC 1039, Escherichia coli ESS, Salmonella typhimurium KCTC 1925.

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Observations of Infection Structures after Inoculation with Colletotrichum orbiculare on the Leaves of Cucumber Plants Pre-inoculated with Two Bacterial Strains Pseudomonas putida or Micrococcus luteus

  • Jeun, Yong-Chull;Lee, Kyung-Hoo
    • Mycobiology
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    • v.33 no.3
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    • pp.131-136
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    • 2005
  • Infection structures were observed at the penetration sites on the leaves of cucumber plants inoculated with Colletotrichum orbiculare using a fluorescence microscope. The cucumber plants were previously drenched with suspension of bacterial strains Pseudomonas putida or Micrococcus luteus. The plants pre-inoculated with both bacterial strains were resistant against anthracnose after inoculation with C. orbiculare. To investigate the resistance mechanism by both bacterial strains, the surface of infected leaves was observed at the different time after challenge inoculation. At 3 days after inoculation there were no differences in the germination and appressorium formation of conidia of C. orbiculare as well as in the callose formation of the plants between both bacteria pre-inoculated and non-treated. At 5 days, the germination and appressorium formation of the fungal conidia were, however, significantly decreased on the leaves of plants pre-inoculated with M. luteus at the concentration with $1.0{\times}10^7\;cfu/ml$. Furthermore, callose formation of plants cells at the penetration sites was apparently increased. In contrast, there were no defense reactions of the plants at the concentration with $1.0{\times}10^6\;cfu/ml$ of M. luteus. Similarly, inoculation P. putida caused no plant resistance at the low concentration, whereas increase of callose formation was observed at the higher concentration. The results of this study suggest that the resistant mechanisms might be differently expressed by the concentration of pre-treatment with bacterial suspension.

Analysis of Waste Water and Isolation of Strains Assimilation Waste Water from Acetaldehyde Plant (아세트 알데히드(특수산업) 공장폐수의 성분과 이용균주의 분리)

  • 정기택;서승교;송형익;박임동;방광웅
    • Korean Journal of Microbiology
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    • v.25 no.4
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    • pp.328-332
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    • 1987
  • As a research for treatment of waste water from acetaldehyde plant by biological method, we investigated general characteristics of the waste water, and isolated and identified some useful bacteria which effectively treated its waste water. Among the total number of 53 strains which were grown in waste water from an acetaldehyde plant, the strains AW-6, AW-22, AW-38 and AW-41 were found to be useful for COD removal of waste water. $COD_{Mn}$ and $BOD_{5}$ of the waste water were 5260 ppm and 6452 ppm, respectively, and pH was 1.85. And the main organic component in waste water was acetic acid which was contained 6.76%. By the taxonomical characteristics, the strains AW-6, AW-22, AW-38 and AW-41 were identified as Micrococcus roseus, Micrococcus luteus, Microbacterium lacticum and Microbacterium laevanifromans or similar strain, respectively.

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