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Diels-Alder Reactions During the Biosynthesis of Sorbicillinoids.

ABSTRACT: The sorbicillinoids are a class of biologically active and structurally diverse fungal polyketides arising from sorbicillin. Through co-expression of sorA, sorB, sorC, and sorD from Trichoderma reesei QM6a, the biosynthetic pathway to epoxysorbicillinol and dimeric sorbicillinoids, which resemble Diels-Alder-like and Michael-addition-like products, was reconstituted in Aspergillus oryzae NSAR1. Expression and feeding experiments demonstrated the crucial requirement of the flavin-dependent monooxygenase SorD for the formation of dimeric sorbicillinoids, hybrid sorbicillinoids, and epoxysorbicillinol in?vivo. In contrast to prior reports, SorD catalyses neither the oxidation of 2',3'-dihydrosorbicillin to sorbicillin nor the oxidation of sorbicillinol to oxosorbicillinol. This is the first report that both the intermolecular Diels-Alder and Michael dimerization reactions, as well as the epoxidation of sorbicillinol are catalysed in?vivo by SorD.

SUBMITTER: Kahlert L

PROVIDER: S-EPMC7154774 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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