C-C bond forming radical SAM enzymes involved in the construction of carbon skeletons of cofactors and natural products.

Published

Journal Article (Review)

Covering: up to the end of 2017 C-C bond formations are frequently the key steps in cofactor and natural product biosynthesis. Historically, C-C bond formations were thought to proceed by two electron mechanisms, represented by Claisen condensation in fatty acids and polyketide biosynthesis. These types of mechanisms require activated substrates to create a nucleophile and an electrophile. More recently, increasing number of C-C bond formations catalyzed by radical SAM enzymes are being identified. These free radical mediated reactions can proceed between almost any sp3 and sp2 carbon centers, allowing introduction of C-C bonds at unconventional positions in metabolites. Therefore, free radical mediated C-C bond formations are frequently found in the construction of structurally unique and complex metabolites. This review discusses our current understanding of the functions and mechanisms of C-C bond forming radical SAM enzymes and highlights their important roles in the biosynthesis of structurally complex, naturally occurring organic molecules. Mechanistic consideration of C-C bond formation by radical SAM enzymes identifies the significance of three key mechanistic factors: radical initiation, acceptor substrate activation and radical quenching. Understanding the functions and mechanisms of these characteristic enzymes will be important not only in promoting our understanding of radical SAM enzymes, but also for understanding natural product and cofactor biosynthesis.

Full Text

Duke Authors

Cited Authors

  • Yokoyama, K; Lilla, EA

Published Date

  • July 18, 2018

Published In

Volume / Issue

  • 35 / 7

Start / End Page

  • 660 - 694

PubMed ID

  • 29633774

Pubmed Central ID

  • 29633774

Electronic International Standard Serial Number (EISSN)

  • 1460-4752

Digital Object Identifier (DOI)

  • 10.1039/c8np00006a

Language

  • eng

Conference Location

  • England