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A single residue change leads to a hydroxylated product from the class II diterpene cyclization catalyzed by abietadiene synthase.

ABSTRACT: Class II diterpene cyclases catalyze bicyclization of geranylgeranyl diphosphate. While this reaction typically is terminated via methyl deprotonation to yield copalyl diphosphate, in rare cases hydroxylated bicycles are produced instead. Abietadiene synthase is a bifunctional diterpene cyclase that usually produces a copalyl diphosphate intermediate. Here it is shown that substitution of aspartate for a conserved histidine in the class II active site of abietadiene synthase leads to selective production of 8?-hydroxy-CPP instead, demonstrating striking plasticity.

SUBMITTER: Criswell J

PROVIDER: S-EPMC3518578 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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A single residue change leads to a hydroxylated product from the class II diterpene cyclization catalyzed by abietadiene synthase.

Criswell Jared J Potter Kevin K Shephard Freya F Beale Michael H MH Peters Reuben J RJ

Organic letters 20121120 23

Class II diterpene cyclases catalyze bicyclization of geranylgeranyl diphosphate. While this reaction typically is terminated via methyl deprotonation to yield copalyl diphosphate, in rare cases hydroxylated bicycles are produced instead. Abietadiene synthase is a bifunctional diterpene cyclase that usually produces a copalyl diphosphate intermediate. Here it is shown that substitution of aspartate for a conserved histidine in the class II active site of abietadiene synthase leads to selective p ...[more]

PMID: 23167845

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