Enediyne Polyketide Synthases Stereoselectively Reduce the β-Ketoacyl Intermediates to β-d-Hydroxyacyl Intermediates in Enediyne Core Biosynthesis
نویسندگان
چکیده
PKSE biosynthesizes an enediyne core precursor from decarboxylative condensation of eight malonyl-CoAs. The KR domain of PKSE is responsible for iterative β-ketoreduction in each round of polyketide chain elongation. KRs from selected PKSEs were investigated in vitro with β-ketoacyl-SNACs as substrate mimics. Each of the KRs reduced the β-ketoacyl-SNACs stereoselectively, all affording the corresponding β-D-hydroxyacyl-SNACs, and the catalytic efficiencies (k(cat)/K(M)) of the KRs increased significantly as the chain length of the β-ketoacyl-SNAC substrate increases.
منابع مشابه
Crystal Structure of Thioesterase SgcE10 Supporting Common Polyene Intermediates in 9- and 10-Membered Enediyne Core Biosynthesis
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