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A close look at a ketosynthase from a trans-acyltransferase modular polyketide synthase.

ABSTRACT: The recently discovered trans-acyltransferase modular polyketide synthases catalyze the biosynthesis of a wide range of bioactive natural products in bacteria. Here we report the structure of the second ketosynthase from the bacillaene trans-acyltransferase polyketide synthase. This 1.95 Å resolution structure provides the highest resolution view available of a modular polyketide synthase ketosynthase and reveals a flanking subdomain that is homologous to an ordered linker in cis-acyltransferase modular polyketide synthases. The structure of the cysteine-to-serine mutant of the ketosynthase acylated by its natural substrate provides high-resolution details of how a native polyketide intermediate is bound and helps explain the basis of ketosynthase substrate specificity. The substrate range of the ketosynthase was further investigated by mass spectrometry.

SUBMITTER: Gay DC

PROVIDER: S-EPMC3966118 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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A close look at a ketosynthase from a trans-acyltransferase modular polyketide synthase.

Gay Darren C DC Gay Glen G Axelrod Abram J AJ Jenner Matthew M Kohlhaas Christoph C Kampa Annette A Oldham Neil J NJ Piel Jörn J Keatinge-Clay Adrian T AT

Structure (London, England : 1993) 20140206 3

The recently discovered trans-acyltransferase modular polyketide synthases catalyze the biosynthesis of a wide range of bioactive natural products in bacteria. Here we report the structure of the second ketosynthase from the bacillaene trans-acyltransferase polyketide synthase. This 1.95 Å resolution structure provides the highest resolution view available of a modular polyketide synthase ketosynthase and reveals a flanking subdomain that is homologous to an ordered linker in cis-acyltransferase ...[more]

PMID: 24508341

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