• YAKHAK HOEJI
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• v.41 no.4
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• pp.530-532
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• 1997

The MICs of various macrolide, lincosamide and streptogramin B antibiotics against highly erythromycin-resistant Escherichia coli 209K strain were evaluated. E. coli 209K showed high MICs against 14-membered macrolides and the relatively weaker resistance to 16-membered macrolides, lincosamides and streptogramin B. The macrolide-phosphotransferase K from E. coli 209K showed greater substrate specificity to the 14-membered macrolide antibiotics than to the 16-membered macrolide antibiotics, lincosamide and streptogramin B. Therefore, it was considered that the high resistance was due to the macrolide-phosphotransferase K.

• Biomolecules & Therapeutics
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• v.29 no.1
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• pp.98-103
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• 2021

The demand for natural substances with anti-melanogenic activity is increasing due to the recent interest in skin whitening. Intensive investigation on the culture broth of Streptomyces sp. SCO-736, a marine bacterium from the Antarctica coast, has led to the isolation of a new natural product named antaroide (1). The chemical structure was established through the interpretation of MS, UV, and NMR spectroscopic data. Antaroide is a nine-membered macrolide with lactone and lactam moieties. To investigate its applicability in skin whitening cosmetics, its anti-melanogenic activity in B16F10 murine melanoma cells was examined. As a result, antaroide displayed strong inhibitory activities against melanin synthesis and also attenuated the dendrite formation induced by the α-melanocyte stimulating hormone (α-MSH). Antaroide suppressed the mRNA expression of the melanogenic enzymes such as tyrosinase, TRP-1 and TRP-2. This suggests that it may serve as a transcriptional regulator of melanogenesis. Collectively, the discovery of this novel natural nine-membered macrolide and its anti-melanogenic activity could give new insights for the development of skin whitening agents.

• Archives of Pharmacal Research
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• v.21 no.1
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• pp.76-78
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• 1998

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.51-56
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• 1993

The structure of herbicidal compound, 3D5, isolated from the culture broth of Streptomyces sp. 3D5, was elucidated as a 16-membered diene macrolide by the spectroscopic method. It was identical with bafilomycin D which has been known to be an insecticidal compound and an inhibitor of $K^{+}-dependent$ ATPase. However, this is the first report which shows that bafilomycin D has a herbicidal activity.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.204.1-204.1
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• 2000

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.764-770
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• 2006

Dihydrochalcomycin (GERI-155), produced by Streptomyces sp. KCTC-0041BP isolated from Korean soil, is a 16-membered macrolide antibiotic consisting of two deoxysugar moieties at C-5 and C-20 positions of a branched lactone ring. The cloning and sequencing of a gene cluster for dihydrochalcomycin biosynthesis revealed a 63-kb nucleotide region containing 25 open reading frames (ORFs). The products of all of these 25 ORFs playa role in dihydrochalcomycin biosynthesis and self-resistance against the compounds synthesized. At the core of this cluster lies a 39.6-kb polyketide synthase (PKS) region encoding eight modules in five giant multifunctional protein-coding genes (gerSI-SV). The genes responsible for the biosynthesis of deoxysugar moieties, D-chalcose and D-mycinose, and their modification and attachment were found on either side of this PKS region. The involvement of this gene cluster in dihydrochalcomycin biosynthesis was confirmed by disruption of the dehydratase (DH) domain in module 3 of the PKS gene and by metabolite analysis.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.829-833
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• 2002

Angiogenesis is an essential event in a variety of physiological and pathological processes. Therefore, effective inhibition of this event is a promising strategy for treating angiogenesis-related diseases, including cancer. The current study investigated two unique bafilomycin-type macrolide inhibitors of angiogenesls, PC-766B' (1) and PC-766B (2). The strain RK97-56 which produced the inhibitors was identified as Nocardia sp. by chemotaxonomic analyses, and the purification of the inhibitors was guided by their anti-angiogenic activities. PC-766B' (1) and PC-766B (2) exhibited potent inhibitory activities towards endothelial cell migration stimulated by the vascular endothelial growth factor (VEGF).