• 한국결정학회지
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• 제18권1_2호
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• pp.10-15
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• 2007

UDP-N-acetylglucosamine enolpyruvyl transferase (MurA; EC 2.5.1.7) catalyzes the first committed step of peptidoglycan biosynthesis in bacteria, i.e., transfer of enolpyruvate from phosphoenolpyruvate to UDP-N-acetyl-glucosamine. Because the crystallization condition contained a high concentration of ammonium sulfate, our inhibitor binding studies were not successful. Therefore, we employed a docking approach to investigate the inhibitor binding. Our results will be useful in structure-based design of specific inhibitors of MurA for antibacterial discovery.

• KSBB Journal
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• 제6권3호
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• pp.223-230
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• 1991

Using the shuttle vector pECCGl between Escherichia coli and Corynebacterium glutamicum and C. glutamicum strain JS231 grown in the medium supplemented with penicillin-G, which inhibits the formation of cross-links in the peptidoglycan of bacterial cell wall, various parameters involved in electroporation system including resistance, electric field strength, capacitance, DNA concentration, and cell density were investigated independently and optimized for the high efficiency transformation of coryneform bacteria. Using cells grown with 0.3U/ml of penicillin-G and harvested at A600 of 0.7-0.8, transformation efficiencies of 107-l08 transformants/$\mu\textrm{g}$ of DNA with Corynebcctertum glutamicum strain JS231 and wild type ATCC13032 were achieved under conditions of 12.5kV/cm of electric field strength, 400 ohms of resistance, $25\mu$F of capacitance, 3$\times$108 cells per transformation(1.2$\times$1010 cells/ml) and 100ng of plasmid DNA per transformation.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.37-43
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• 1997

Triphenylmethane was decolorized rapidly by enterbacter cloacae MG 82 at initial reaction time. The spheroplast showed higher activity of triphenylmentane decolorization than that of intact cell suspension. The outer part of the bacterial cell envelope and the peptidoglycan are important for the function of transport barrier of triphenylmethane. In intact cell, decolorization activity was higher at 37$\circ $C than at $\circ $C, indicating that triphenylmethane decolorization is due to the enzyme reaction. Culture filtrate showed no decolorization activity, while cell-free extract appeared high activity of 1.45 units, clearly showing that decolorization activity was due to the cell-free extract. Comparing decolorization activities of cell fractions, it was found that decolorization activity was located at the compartment of cytoplasmic membrane. The enzyme activity was also shown to be Mg$^{++}$-dependent. The optimum pH and temperature of enzyme activity were 7.0 and 50$\circ $C, respectively. The thermostability of this enzyme at 35$\circ $C was kept to 58% for 3 hours.

• 한국미생물·생명공학회지
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• 제19권6호
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• pp.561-567
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• 1991

Identification of the Actinomycetes isolate strain No. 497 producing an actinomycin antibiotic MT-497 was performed by ISP and chemotaxonomic methods. The strain Nu. 497 formed various shapes of sclerotia and smooth surface spore. Menaquinone MK-9 ($H_6, H_8$) and iso-, anteiso-branched $C_{15}C_{17}$ fatty acids were detected from whole cell extract. The wall chemotype of stram No. 497 was decided as wall chemotype I from the analysis of DAP isomer, peptidoglycan type and sugar pattern. From these morphological, chemotaxonomic characteristics and analysis of various physiological characteristics. the strain No. 497 was identified as Streptomyces nigrifaciens.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.307-316
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• 2015

Beginning from the recognition of FtsZ as a bacterial tubulin homolog in the early 1990s, many bacterial cytoskeletal elements have been identified, including homologs to the major eukaryotic cytoskeletal elements (tubulin, actin, and intermediate filament) and the elements unique in prokaryotes (ParA/MinD family and bactofilins). The discovery and functional characterization of the bacterial cytoskeleton have revolutionized our understanding of bacterial cells, revealing their elaborate and dynamic subcellular organization. As in eukaryotic systems, the bacterial cytoskeleton participates in cell division, cell morphogenesis, DNA segregation, and other important cellular processes. However, in accordance with the vast difference between bacterial and eukaryotic cells, many bacterial cytoskeletal proteins play distinct roles from their eukaryotic counterparts; for example, control of cell wall synthesis for cell division and morphogenesis. This review is aimed at providing an overview of the bacterial cytoskeleton, and discussing the roles and assembly dynamics of bacterial cytoskeletal proteins in more detail in relation to their most widely conserved functions, DNA segregation and coordination of cell wall synthesis.

• 생명과학회지
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• 제2권4호
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• pp.232-239
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• 1992

UDP_GlcNAc is metabolized to form vegetative cell wall, cortical peptidoglycans, and outermost layer consisting of galactosamine-6-phosphate ploysaccharide in life cycle of Bacillus megaterium. To obtain a better understanding of the UDP-GlcNAc regulation, we examined the activity of the common first enzyme for the synthesis of nucleotide precursors of peptidoglycans, enoylpyruvate transferase by newly developed method. Both the specific and the total activity decreased after the end of exponential growth followed by and increase from t5 but decreased again parallel to the appearance of the activity of UDP_GlcNAc-4-epimerase. Antibody specificity to anti-transferase IgG and the elution profile on DEAE-Sepharose revealed that B. megaterium has at least two enoylpyruvate transferase isozymes, and UDP_GlcNAc was metabolized to vegetative cell wall and cortical peptidoglycan by each isozme in exponential growth and in sporulation, respectively in life cycle.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1992년도 제1회 신약개발 연구발표회 초록집
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• pp.57-57
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• 1992

Teicoplanin은 actinoplanes teicomyceticus의 발효산물로서 vancomycin과 같은 glycopeptide 계열의 항균제이며, 그 작용기전은 세포벽 합성과정중 peptidoglycan의 중합을 억제하는 것으로 vancomycin과 유사하나 vancomycin과 달리 근육에 주사할 수 있으며 "red man's syndrome"이 생기지 않고 vancomycin보다 반감기가 길다. 그람양성균 감염증에 대한 teicoplanin의 효능 및 안전성을 조사하기 위하여, 그람양성균에 의한 감염증 또는 그람양성균과 그람음성균에 의한 혼합감염증이 확인되거나 의심되었던 환자 46명을 대상으로 teicoplanin과 vancomycin을 투여하였다. 투약 환자중 임상적인 반응을 평가할 수 있는 환자의 수는 vancomycin의 경우 투약환자 22명중 21명, teicoplanin의 경우 24명중 19명이였다. Vancomycin군중 임상적 반응의 평가에서 제외된 1명은 수술 후 흉막강에 MRSA 에 의한 농양으로 투약 29일째에 뇌출혈로 사망하였던 예로, 추적-배양검사에서는 MRSA가 제거 되었다. Teicoplanin군에서는 항균제 투여 중 간경변증에 의한 식도출혈 1예, 수술후 위장관 출혈 1예, 뇌 색전중 1예가 사망하였고, 1예는 Teicoplanin에 의한 심한 피부발진으로, 다른 1예는 봉와직염의 임상진단이 조직검사결과 악성종양의 근육침범으로 밝혀져 투약을 중단하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.493-496
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• 2002

용균작용을 하는 lysozyme을 난백으로부터 분리하기 위해 이온교환크로마토그래피를 사용하였다. 용출시에 gradient를 걸어준 결과 젤과 약하게 결합된 단백질과 강하게 결합된 단백질이 분리되어 나옴을 SDS-PAGE와 Lowry methode를 통하여 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제2권3호
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• pp.161-165
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• 1992

The gene encoding the bacteriolytic enzyme cell wall peptidoglycan hydrolase from alkalophilic Bacillus sp. was cloned in E. coli using pBR322 as a vector. A recombinant plasmid, designated pYTR451, was isolated and the size of the cloned HindIII fragment was found to be 4.8 Kb. The cell wall hydrolysis activity of an extract of the E. coli harboring the recombinant plasmid pYTR 451 was detected by SDS- polyacrylamide gel containing 0.2% (w/v) purified cell wall of Bacillus sp. The molecular weight of the enzyme was estimated to be about 27, 000 corresponding to the molecular weight of the Bacillus sp. bacteriolytic enzyme. The recombinant plasmid was found to contain the fragment originated from Bacillus sp. YJ-451 chromosomal DNA by Southern hybridization.

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.191-196
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• 1996

The bacteriolytic enzyme produced from Bacillus subtilis SH-1 was purified and characterized, and its molecular weight was determined. The bacteriolytic enzyme activity was increased about 66.5 times via purification with recovery yield of 18.5%. The optimum pH and temperature of this enzyme were 9.0 and 50$\circ$C. The enzyme was stable within a pH range of 6.0-10.0 and unstable above 60 . The molecular weight of the enzyme was estimated to be 23,000 dalton in a form of monomer with no other subunits. Effect of the enzyme on the lysis of bacteria engaged in food posion was tested. The lysis degree was below 31% against Gram negative bacteria and above 48% in Gram positive bacteria. The values higher than 73% were obtained against Vibrio sp. and Listeria sp. As the turbidity of dissolved peptidoglycan clecreases, the free amino group levels were increased. And, based on hydrolysis of casein, this enzyme was thought to be an endopeptidase.