Radical SAM enzymes: surprises along the path to understanding mechanism

  • William E. Broderick
  • Joan B. BroderickEmail author
Mini Review
Part of the following topical collections:
  1. Joan Broderick: Papers in Celebration of Her 2019 ACS Alfred Bader Award in Bioinorganic or Bioorganic Chemistry


As the field of radical SAM enzymology has grown from a few examples in the 1990s to hundreds of thousands today, a fundamental question has remained: how does Nature use S-adenosyl-l-methionine to initiate radical reactions? This was a driving question when we first began studying pyruvate formate-lyase activating enzyme in 1993, and our journey for answers has brought us to many surprising discoveries, from the direct coordination of SAM to a unique iron in a [4Fe-4S] cluster, to our recent discovery of an organometallic intermediate and our ability to quantitatively produce and characterize the long-sought 5′-deoxyadenosyl radical intermediate. These adventures and what we have learned along the way about this fundamentally novel chemistry is described in this review.

Graphic abstract


S-adenosylmethionine Radical SAM Organometallic Deoxyadenosyl radical 



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Copyright information

© Society for Biological Inorganic Chemistry (SBIC) 2019

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryMontana State UniversityBozemanUSA

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