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A Polyketide Cyclase That Forms Medium-Ring Lactones.

ABSTRACT: Medium-ring lactones are synthetically challenging due to unfavorable energetics involved in cyclization. We have discovered a thioesterase enzyme DcsB, from the decarestrictine C1 (1) biosynthetic pathway, that efficiently performs medium-ring lactonizations. DcsB shows broad substrate promiscuity toward linear substrates that vary in lengths and substituents, and is a potential biocatalyst for lactonization. X-ray crystal structure and computational analyses provide insights into the molecular basis of catalysis.

SUBMITTER: Gao DW

PROVIDER: S-EPMC8126169 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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A Polyketide Cyclase That Forms Medium-Ring Lactones.

Gao De-Wei DW Jamieson Cooper S CS Wang Gaoqian G Yan Yan Y Zhou Jiahai J Houk K N KN Tang Yi Y

Journal of the American Chemical Society 20201222 1

Medium-ring lactones are synthetically challenging due to unfavorable energetics involved in cyclization. We have discovered a thioesterase enzyme DcsB, from the decarestrictine C1 (<b>1</b>) biosynthetic pathway, that efficiently performs medium-ring lactonizations. DcsB shows broad substrate promiscuity toward linear substrates that vary in lengths and substituents, and is a potential biocatalyst for lactonization. X-ray crystal structure and computational analyses provide insights into the mo ...[more]

PMID: 33351624

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