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Structural determinants of reductive terpene cyclization in iridoid biosynthesis.

ABSTRACT: The carbon skeleton of ecologically and pharmacologically important iridoid monoterpenes is formed in a reductive cyclization reaction unrelated to canonical terpene cyclization. Here we report the crystal structure of the recently discovered iridoid cyclase (from Catharanthus roseus) bound to a mechanism-inspired inhibitor that illuminates substrate binding and catalytic function of the enzyme. Key features that distinguish iridoid synthase from its close homolog progesterone 5?-reductase are highlighted.

SUBMITTER: Kries H

PROVIDER: S-EPMC4685742 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Structural determinants of reductive terpene cyclization in iridoid biosynthesis.

Kries Hajo H Caputi Lorenzo L Stevenson Clare E M CEM Kamileen Mohammed O MO Sherden Nathaniel H NH Geu-Flores Fernando F Lawson David M DM O'Connor Sarah E SE

Nature chemical biology 20151109 1

The carbon skeleton of ecologically and pharmacologically important iridoid monoterpenes is formed in a reductive cyclization reaction unrelated to canonical terpene cyclization. Here we report the crystal structure of the recently discovered iridoid cyclase (from Catharanthus roseus) bound to a mechanism-inspired inhibitor that illuminates substrate binding and catalytic function of the enzyme. Key features that distinguish iridoid synthase from its close homolog progesterone 5β-reductase are h ...[more]

PMID: 26551396

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