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Pyran formation by an atypical CYP-mediated four-electron oxygenation-cyclization cascade in an engineered aureothin pathway.

ABSTRACT: Small changes, big effect: A new aureothin derivative, aureopyran, which features an unusual pyran backbone, was generated by simply altering the enzymatic methylation topology. The ?-pyrone ring hampers the correct placement of the polyketide backbone in the multifunctional cytochrome P450 monooxygenase AurH. Instead of a tetrahydrofuran ring, an oxo intermediate is formed that readily undergoes a rare electrocyclization reaction.

SUBMITTER: Richter M

PROVIDER: S-EPMC3517090 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Pyran formation by an atypical CYP-mediated four-electron oxygenation-cyclization cascade in an engineered aureothin pathway.

Richter Martin M Busch Benjamin B Ishida Keishi K Moore Bradley S BS Hertweck Christian C

Chembiochem : a European journal of chemical biology 20120907 15

Small changes, big effect: A new aureothin derivative, aureopyran, which features an unusual pyran backbone, was generated by simply altering the enzymatic methylation topology. The α-pyrone ring hampers the correct placement of the polyketide backbone in the multifunctional cytochrome P450 monooxygenase AurH. Instead of a tetrahydrofuran ring, an oxo intermediate is formed that readily undergoes a rare electrocyclization reaction. ...[more]

PMID: 22961965

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