BIOSYNTHESIS OF LASALOCID. I

Abstract

The biosynthesis of lasalocid A (formerly antibiotic X-537 A) in cultures of Strepto-myces lasaliensis has been studied using 13C- and 14C-labelled precursors. The antibiotic is derived from five acetate, four propionate and three butyrate units. This study has provided the first illustration of an ethyl group arising from butyrate and 2-ethylmalonate.