• Journal of Sericultural and Entomological Science
• /
• v.40 no.1
• /
• pp.63-69
• /
• 1998

Twenty seven out of ca. 5,000 actinomycete strains, which were isolated from soil collected throughout the country, showed antibicrobial effects against fungai, Rhizopus stronifer (ATCC 6227a), Rhizoctonia solani (KCCM 11271) and yeast, Candida albicans (ATCC 10231). From these antifungal microorganisms, we further selected seven strains which seemed to produce insecticidal substances with in vivo test, using silkworm, Bombyx mori and beet armyworm, Spodoptera exigua. Morphological and biochemical experiments revealed that three strains out of seven were Streptomyces. Further investigations on the physical and chemical properties of these antifungal and insecticidal substances are now in progress.

• Microbiology and Biotechnology Letters
• /
• v.28 no.3
• /
• pp.129-133
• /
• 2000

Different actinomycete strains were isolated from natural lime caves of Ondal Chemongok Hwanseon and Yongyeon which are located at Kangwon or chungcheongbook province in Korea and were identified to the genus level. Soil sam-ples were collected at 6 sites inside and 2 sites outside of each natural lime cave, As the result the strains belonging to genus Streptomyces and rare actinomycetes were isolated at the average of 2.1 and 3.4 strains per g soil on inside cave whereas which were isolated at the 6.0 and 1.8 strains per g soil on outside cave. How-ever the generic distribution of Streptomyces and rare actinomycetes isolated from outside cave was quite dif-ferent from that of inside cave. It was shown that rare actinomycetes at natural lime caves is generally highly abundant than Streptomyces.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.1
• /
• pp.25-29
• /
• 2012

Marine actinomycetes isolated from seaweed were screened for growth activation effects on the biodiesel-producing microalgae Dunaliella salina. Of the 98 actinomycetes studied, strain 288-11 isolated from the rhizosphere of Undaria pinnatifida showed potent growth activation. The strain was identified as Streptomyces anulatus based on 16S rDNA sequence analysis. The cell density increased up to 2.1-fold with the addition of 1 mg/mL of extract to the medium. To understand the effect of adding S. anulatus extract, the gross biochemical composition and fatty acids of D. salina were determined.

• BMB Reports
• /
• v.31 no.5
• /
• pp.475-483
• /
• 1998

Many antibiotics contain partially deoxygenated sugar components that are usually essential for biological activity, affinity, structural stability, and solubility of antibiotics. Gene probes of the biosynthetic genes related with the deoxysugar were obtained from PCR. Primers were designed from the conserved peptide sequences of the known dTDP-D-glucose 4,6-dehydratases, which are the key step enzymes in the biosynthesis of deoxysugar. The primers were applied to amplify parts of dehydratase genes to 27 actinomycetes that produce the metabolites containing deoxysugar as structural constituents. About 180 and 340 bp DNA fragments from all of the actinomycetes were produced by PCR and analyzed by Southern blot and DNA sequencing. The PCR products were used as gene probes to clone the biosynthetic gene clusters for the antibiotic mithramycin, rubradirin, spectinomycin, and elaiophyrin. This method should allow for detecting of the biosynthetic gene clusters of a vast array of secondary metabolites isolated from actinomycetes because of the widespread existence of deoxysugar constituents in secondary metabolites.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.3
• /
• pp.501-505
• /
• 2010

1-Acetyl-$\beta$-carboline was isolated as an anti-MRSA agent from the fermentation broth of a marine actinomycete isolated from marine sediment. The producing strain was identified to be Streptomyces sp. by phylogenetic analysis of the 16S rRNA gene sequence. The anti-MRSA agent was isolated by bioactivity-guided fractionation of the culture extract by solvent partitioning, ODS open flash chromatography, and purification with a reversed-phase HPLC. Its structure was elucidated by extensive 2D NMR and mass spectral analyses. Combination of 1-acetyl-$\beta$-carboline with ampicillin exhibited synergistic antibacterial activity against MRSA.

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

• Natural Product Sciences
• /
• v.21 no.4
• /
• pp.248-250
• /
• 2015

A new ${\alpha}-pyrone$ derivative, violapyrone J (1), and along with the two known violapyrones B (2) and C (3) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. SC0718. The structure of violapyrone J (1) was elucidated from 1D and 2D NMR spectroscopic analyses.

• Journal of Microbiology
• /
• v.41 no.2
• /
• pp.83-88
• /
• 2003

The taxonomic position of actinomycete strain SCNU5$\^$T/, isolated from extensive foam in the aeration basin of an activated sludge process, was clarified by phenotypic, chemotaxonomic and phylogenetic analyses. The strain possesses wall chemotype IV, MK-9(H$\^$0/), as the major menaquinone, and contains saturated, monounsaturated and 10-methyl branched fatty acids. The G+C content of its DNA is 68.1 mol%. Phenotypic data and DNA relatedness to known species indicate that the strain SCNU5$\^$T/ represents a new species within the genus Tsukamurella, for which we propose the name Tsukamurella sunchonensis SP. NOV. The type Strain Of T. sunchonensis is SCNU5$\^$T/ (=KCTC 9827$\^$T/).

• Microbiology and Biotechnology Letters
• /
• v.22 no.4
• /
• pp.373-381
• /
• 1994

An actinomycete strain, HSL-613 was isolated -from soil and identified by International Streptomyces Project (ISP) and chemotaxonomic methods. The spore chain of the strain HSL-613 appears in a spiral shape, and its spores are spherical shape with smooth surface. The cell wall contains LL-diaminopimelic acid (DAP). Menaquinone MK-9 (H$_{6}$, H$_{8}$) and iso- and anteiso-branched fatty acids were detected from whole cell extract. Sugars identified from whole cell extract include galactose, glucose, mannose and ribose, which are distinct from general sugar patterns of Streptomyces. Average G+C content in the chromosome is 59%. 5S rRNA of HSL-613 consists of 120 nucleotides as determined by comparing with that of a type strain Streptomyces griseus subsp. KCTC 9080. Through morphological, physiological, and chemical characterization, HSL-613 was identified and named as Streptomyces sp. HSL-613.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2004.06a
• /
• pp.165-168
• /
• 2004

An anti-fungal material producing actinomycete was isolated from domestic soil. This strain was identified as Streptomyces albogriseus by 16S rDNA sequence. YEME (yeast extract 4g, malt extract 10g, glucose 4g, D.W 1l , pH $7.0{\pm}0.2$) medium was used for production of anti-fungal materials. S. albogriseus was cultured in a shaking incubator for 2 weeks at 150 rpm and $25{\pm}1^{\circ}C$. An anti-fungal material produced by S. albogriseus was identified at 340nm by uv/vis- spectrometer and it showed powerful anti-fungal activity. This is the first report that secondary metabolite produced by S. albogriseus showed an activity against phytopathogenic fungi such as Collectrichum coccodes, Botrytis cinerea, Cladosporium cucumerinum, Didymella bryoniae.