Production of octaketide polyenes by the calicheamicin polyketide synthase CalE8: implications for the biosynthesis of enediyne core structures.

ABSTRACT: Enediyne antibiotics are categorized according to the presence of either a 9- or 10-membered ring within their polyketide-derived core structures. Recent literature reports have favored the notion that biosynthetic divergence of the two structural families is determined by the enediyne polyketide synthases (PKSs) alone. We now disclose the simultaneous in vitro production of three octaketide polyenes by biosynthetic enzymes for the 10-membered enediyne calicheamicin gamma(1)(I), including the elusive beta-keto acid precursor to a previously described C15 methyl hexaenone. Alongside these two polyene products, we have additionally detected a hydrocarbon heptaene previously isolated only from 9-membered enediyne systems. The discovery of the heptaene in the calicheamicin system promotes a mo

SUBMITTER: Belecki K 

PROVIDER: S-EPMC2760317 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature