Aminofutalosine Synthase: Evidence for Captodative and Aryl Radical Intermediates Using β‑Scission and SRN1 Trapping Reactions Academic Article uri icon


  • Aminofutalosine synthase (MqnE) is a radical SAM enzyme involved in the menaquinone biosynthetic pathway. In this communication, we propose a novel mechanism for this reaction involving the addition of the adenosyl radical to the substrate double bond to form a captodative radical followed by rearrangement and decarboxylation to form an aryl radical anion which is then oxidized by the [4Fe-4S]+2 cluster. Consistent with this proposal, we describe the trapping of the captodative radical and the aryl radical anion using radical triggered C-Br fragmentation reactions. We also describe the trapping of the captodative radical by replacing the vinylic carboxylic acid with an amide.

author list (cited authors)

  • Joshi, S., Mahanta, N., Fedoseyenko, D., Williams, H., & Begley, T. P.

publication date

  • January 1, 2017 11:11 AM