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PubMed · 4077729

Demethylavermectins. Biosynthesis, isolation and characterization.

M D Schulman·D Valentino·O D Hensens·D Zink·M Nallin·L Kaplan·D A Ostlind
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Abstract

Streptomyces avermitilis normally produces eight avermectins. Avermectin A components contain three methoxyl groups; two on the oleandrose disaccharide and one on the aglycone moiety at C5. Avermectin B components contain methoxyl groups only on the oleandrose disaccharide. Sinefungin inhibits methylation at all three sites. Addition of sinefungin to S. avermitilis Agly-1, a mutant which produces virtually only avermectin aglycone A components, alters the fermentation and causes an accumulation of avermectin aglycone B components. Addition of sinefungin to S. avermitilis 08, a high producing strain, results in accumulation of 8 new avermectins which lack methoxyl groups on the oleandrose moieties as well as the aglycone. These new avermectins were isolated and shown to possess anthelmintic and insecticidal activity.

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AdenosineAnthelminticsInsecticidesIvermectinLactonesMethyltransferasesStreptomycesJournal Article

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BibTeXRIS

M D Schulman, D Valentino, O D Hensens, D Zink, M Nallin, L Kaplan, D A Ostlind. 1985. Demethylavermectins. Biosynthesis, isolation and characterization.. https://doi.org/10.7164/antibiotics.38.1494

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