• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.71-71
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.285.1-285
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• 2000

• Proceedings of the Microbiological Society of Korea Conference
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• 2006.05a
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• pp.108-110
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• 2006

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.81-86
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• 2004

Among the annotated ORFs of Streptomyces coelicolor, SCO7697 was supposed to encode for phytase (myo-inositol hexakisphosphate phosphohydrolase). The DNA fragment containing SCO7697 was cloned by the PCR from the chromosomal DNA of S.coelicolor A3(2)M. The cloned fragment was introduced into E. coli expres-sion vector, pET28a(+), to yield two recombinant plasmids, pET28-SP and pET28-LP, which were designed to encode different length of proteins. When the pET28-SP and pET28-LP were introduced into E. coli BL21, the transformants successfully overexpressed recombinant proteins, but the molecular weights of the expressed pro-teins were appeared bigger than those of expected in SDS-polyacrylamide gel electrophoresis. The shift of cul-tural temperature from 37 to $30^{\circ}C$ made most of expressed protein be solubilized. The expressed protein, however, did not show any phytase activity. When the DNA fragment with its own promoter placed on the E. coli-Streptomyces vector, pWHM3, and introduced into S. lividans, the phytase activity was not detected either. These results suggest that even though the SCO7697 was annotated as a probable phytase with high probability (E value is $6e^{-89}$), the real product doest not have phytase activity.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.551-558
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• 1992

The extracellular endoinulase from Streptomyces sp. 556 was purified and characterized, The culture broth was fractionated by ammonium sulfate saturation followed by DEAE-cellulose column chromatography and 5ephadex G-200 gel filtration, The ultimately purified fraction revealed a single band in 7.5% polyacrylamide gel electropherogram. The purified enzyme showed the maximal activity at pH 5.5-6.0 and $50^{\circ}C$, but lost 93% of inulase activity after 30 min incubation at $55^{\circ}C$ . The essen.tial amino acid residue for catalytic activity appeared to be tryptophan. This endo inulase was activated by $Mn^{2+}$, whereas inactivated by $Ag^{+}$, $Hg^{+}$, $Cu^{2+}$, $Zn^{2+}$, $Fe^{3+}$ and $Mo^{6+}$ EDTA and 8-hydroxyquinoline inhibited the enzyme so that the enzyme was considered to be a metalloenzyme. The Km value for inulin was 0.287 mM, and no invertase or $\alpha$-glucosidase activity was found in the enzyme.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.260-264
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• 1996

An isolate, 90-GT-129 was found to produce antibiotics with a selective inhibitory activity against Streptococcus pyogenes and Xanthomonas sp. The isolate formed a gray spiral aerial spore mass with smooth surface. Analysis of the cell wall acid hydrolysate of the isolate revealed presence of LL-di-aminopimelic acid, which indicates that the isolate belongs to a cell wall type Ⅰ actinomycetes. Cultural and physiological characteristics of the isolate placed it in Streptomyces rochei synonym cluster. A comparison of the isolate with 26 reference strains of Streptomyces rochei synonym demonstrated differences in physiological and cultural characteristics.

• Journal of Microbiology and Biotechnology
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• v.5 no.6
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• pp.324-334
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• 1995

The actinomycete strain A 11 was antagonistic to plant pathogenic fungi Phytophthora capsid and Magnaporthe grisea. Based on the diaminopimelic acid (DAP) type and morphological characteristics examined by scanning electron microscopy, the strain A 11 was confirmed to belong to the genus Streptomyces. Based on Willcox probability and similarity level, the strain A 11 was numerically identified as Streptomyces flaveus using TAXON program of Ward and Goodfellow. Antibiotic production of S. flaveus strain A 11 was most favorable when cultured on glycerol yeast extract peptone (GYP) agar for 20 days at $28^{\circ}C$. The crude antibiotics from solid GYP agar cultures of the strain A 11 were most effective against Phytophthora capsici and Sclerotinia sclerotiorum among the fungi tested. Antifungal activity of the antibiotics against Alternaria solani, Botryosphaeria dothidea, Cercospora capsici, Magnaporthe grisea, and Rhizoctonia solani was somewhat high, whereas Colletotrichum gloeosporioides and Fusarium oxysporum f. sp. cucumerinum were rarely inhibited even at high concentrations.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.410-414
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• 1992

Numerical identification was carried out for an isolate of Streptomyces strain producing the extracellular p-lactamase inhibitor. Fifty taxonomic unit characters were tested and the data were analyzed numerically using the TAXON program. The isolate was identified to the major cluster 5 of Streptomyces and it was best matched to Streptomyces omiyaensis which is a synonym of Streptomyces exfoliatus. Therefore, it was concluded that the isolate was identified to be a strain (SMF 19) of Streptomyces exjbliatus.

• Journal of Life Science
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• v.21 no.4
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• pp.589-595
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• 2011

This work focused on screening and characterizing antibiotic-producing actinomycetes to develop new antibiotics that can overcome the growing resistance of disease-causing microbes. One-hundred actinomycetes strains were isolated from soil samples from Chungcheongbuk-do, Korea using various kinds of actinomycetes isolation media, including a starch casein agar medium and potato dextrose agar (PDA). Among them, strain BCNU 1030 was determined to show strong antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA). Biochemical, physiological, and 16S rRNA sequence analyses indicated that strain BCNU 1030 belonged to the genus Streptomyces. Strain BCNU 1030 exhibited antibiotic activity against a wide range of bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentration (MIC) of BCNU 1030 dichloromethane extract was determined to be $0.78\;{\mu}g/ml$ for MRSA CCARM 3090. Therefore, Streptomyces sp. BCNU 1030 has potential for anti-MRSA drug development.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.138-145
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• 2001

The hydrophobic spores of Streptomyces sp. AA8321 isolated from the Antarctic coast displayed demulsification ability. The aerial spores demulsified an emulsion of kerosene/$0.2\%$ Triton X-100 (2:1, v/v) to $50\%$ and $95\%$ within 1 min contact at the concentrations of $5.0{\times}10^7$ and $1.0{\times}10^8$ spores/ml, respectively. A cold shock protein (csp) gene was cloned from the hydrophobic spore- producing Streptomyces sp. AA8321 using PCR. It encoded a low molecular protein with 68 amino acids showing very low homology with previously reported csp genes. Only the sequence of the first six amino acids was just the same and yet others were different. RNA blot analysis indicated that the csp gene was induced by cold shock, i.e., transferring from $30^{\circ}C$ to $10^{\circ}C$, and this cold shock response proposed that the isolated gene be a new type of csp gene.