title: Incorporation of 14C-labeled compounds into sinefungin (A9145), a nucleoside antifungal antibiotic.
abstract: Streptomyces griseolus produces a complex of antifungal nucleoside antibiotics that contain an ornithine residue linked to the ribose moiety of adenosine. 14C-Labeled compounds were added to cultures of S. griseolus (approximately 0.5 muCi/ml culture broth) and the amount of label incorporated into the two major antifungal components (sinefungin and factor C) was measured. Substantial incorporation (16 approximately 52%) was obtained with adenosine [8-14C], ATP [14C(u)], adenine [8-14C], L-ornithine [14C(u)], and DL-citrulline [5-14C]. Glycine glucose L-arginine, and acetate were incorporated to the extent of 1.7 approximately 4.7%. Studies were conducted on the fermentation time course and on the time dependence of label incorporation in order to optimize the incorporation of labeled adenine into sinefungin. Adenine [8-14C] incorporation and sinefungin specific activity were highest 48 hours after label addition and both declined during subsequent incubation. As much as 43% of the labeled adenine was incorporated into the antibiotic and sinefungin was produced with a specific activity of 24.8 muCi/mg. The labeling experiments suggest that a performed adenine derivative (e.g., an adenine nucleotide) and ornithine (or a closely related metabolite) are direct biosynthetic precursors of sinefungin.
mesh_terms: D000225:Adenine / Q000378:metabolism; D000935:Antifungal Agents / Q000096:biosynthesis* / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D012440:Saccharomyces / Q000187:drug effects; D013302:Streptomyces / Q000378:metabolism*; D013997:Time Factors
chemical_list: D000935:Antifungal Agents; D004247:DNA; D000225:Adenine