Solution structures of the acyl carrier protein domain from the highly reducing type I iterative polyketide synthase CalE8.

ABSTRACT: Biosynthesis of the enediyne natural product calicheamicins γ(1) (I) in Micromonospora echinospora ssp. calichensis is initiated by the iterative polyketide synthase (PKS) CalE8. Recent studies showed that CalE8 produces highly conjugated polyenes as potential biosynthetic intermediates and thus belongs to a family of highly-reducing (HR) type I iterative PKSs. We have determined the NMR structure of the ACP domain (meACP) of CalE8, which represents the first structure of a HR type I iterative PKS ACP domain. Featured by a distinct hydrophobic patch and a glutamate-residue rich acidic patch, meACP adopts a twisted three-helix bundle structure rather than the canonical four-helix bundle structure. The so-called 'recognition helix' (α2) of meACP is less negatively charged than the typical ty

SUBMITTER: Lim J 

PROVIDER: S-EPMC3107222 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature