Investigation of the mechanism of the SpnF-catalyzed [4+2]-cycloaddition reaction in the biosynthesis of spinosyn A.

ABSTRACT: The Diels-Alder reaction is one of the most common methods to chemically synthesize a six-membered carbocycle. While it has long been speculated that the cyclohexene moiety found in many secondary metabolites is also introduced via similar chemistry, the enzyme SpnF involved in the biosynthesis of the insecticide spinosyn A in Saccharopolyspora spinosa is the first enzyme for which catalysis of an intramolecular [Formula: see text]-cycloaddition has been experimentally verified as its only known function. Since its discovery, a number of additional standalone [Formula: see text]-cyclases have been reported as potential Diels-Alderases; however, whether their catalytic cycles involve a concerted or stepwise cyclization mechanism has not been addressed experimentally. Here, we report

SUBMITTER: Jeon BS 

PROVIDER: S-EPMC5625926 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature