Biosynthesis of antibiotics of the virginiamycin family. 4. Biosynthesis of A2315A

Abstract

poured into saturated NaCl solution, and isolated with ether. Crystallization from ether gave 2.41 g (79.5%) as a first crop and 470 mg (14.7%) as a second crop: mp 109-110 °C; [ ] +3.80°(

Biosynthesis of polyketides by trans-AT polyketide synthases

“…[361][362][363] Analogous patterns were observed for 221. 363,364 One notable experiment conducted on 218 was a clever labeling technique employing the delayed release of acetate from serine. This method allowed Kingston et al to distinguish between several alternative hypothetical pathways of b-branching and to propose the correct mechanism of this important type of polyketide modification (see Fig.…”

Biosynthesis and attachment of novel bacterial polyketide synthase starter units

“…The fatty acid profile of the manumycin-group producing strain Streptomyces nodosus reflects this mixed use of starter units with mixtures of linear, branched-chain, and ω-cyclohexyl fatty acids. 34 Valine-derived isobutyryl-CoA is the PKS starter unit in several other actinomycete systems, including the linear polyketide tautomycin 35 7, mixed polyketide-peptides belonging to the virginiamycin family such as virginiamycin M 1 36 8, pristinamycin II B 37 and antibiotic A2315A, 38 the macrolide antibiotic LL-F28249-α (nemadectin) 9, 39 and possibly in the antifungal polyketides butyrolactols A 10 and B 11. 40 The possibility of a t-valeryl starter unit derived from t-leucine is very attractive for the unusual terminal t-butyl group in 10, although it is probably derived from an isobutyrate starter unit that is subsequently methylated by S-adenosyl-methionine.…”

Chemistry and Biology of the Streptogramin A Antibiotics

“…LeFevre and Kingston have elucidated the biosynthetic origin of madumycin II (produced by Actinoplanes philippinensis) using 13 C and 2 H labeled precursors [16]. By analogy to the biosynthesis of virginiamycin M2 (vide supra), the C4-C7 and C10-C18 chains are accessed by following the link in the citation at the bottom of the page.…”

“…Bentham Science Publishers does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Bentham Science Publishers. 16 …”