Catalytic mechanism and endo-to-exo selectivity reversion of an octalin-forming natural Diels-Alderase.

ABSTRACT: We have previously reported the identification of CghA, a proposed Diels-Alderase responsible for the formation of the bicyclic octalin core of the fungal secondary metabolite Sch210972. Here we show the crystal structure of the CghA-product complex at a resolution of 2.0 Å. Our result provides the second structural determination of eukaryotic Diels-Alderases and adds yet another fold to the family of proteins reported to catalyse [4 + 2] cycloaddition reactions. Site-directed mutagenesis-coupled kinetic characterization and computational analyses allowed us to identify key catalytic residues and propose a possible catalytic mechanism. Most interestingly, we were able to rationally engineer CghA such that the mutant was able to catalyse preferentially the formation of the energetically dis

SUBMITTER: Sato M 

PROVIDER: S-EPMC9302879 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature