Discovery of branching meroterpenoid biosynthetic pathways in Aspergillus insuetus: involvement of two terpene cyclases with distinct cyclization modes.

ABSTRACT: The aromatic polyketide 3,5-dimethylorsellinic acid (DMOA) serves as a precursor for many fungal meroterpenoids. A large portion of DMOA-derived meroterpenoids are biosynthesized via the cyclization of (6R,10'R)-epoxyfarnesyl-DMOA methyl ester (1). Theoretically, although 1 can be cyclized into many products, only three cyclization modes have been reported. Here, we discovered a meroterpenoid biosynthetic gene cluster in Aspergillus insuetus CBS 107.25, which encodes the biosynthetic enzymes for 1 along with a terpene cyclase that is phylogenetically distantly related to the other characterized cyclases of 1. Intriguingly, InsA7, the terpene cyclase, folds 1 in a pre-boat-chair conformation, generating a new meroterpenoid species with an axially oriented hydroxy

SUBMITTER: Tang J 

PROVIDER: S-EPMC9473517 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature