Tryptophan Lyase (NosL): A Cornucopia of 5'-Deoxyadenosyl Radical Mediated Transformations. Academic Article uri icon


  • Tryptophan lyase (NosL) is a radical S-adenosyl-l-methionine (SAM) enzyme that catalyzes the formation of 3-methyl-2-indolic acid from l-tryptophan. In this paper, we demonstrate that the 5'-deoxyadenosyl radical is considerably more versatile in its chemistry than previously anticipated: hydrogen atom abstraction from N-cyclopropyltryptophan occurs at C rather than the amino group with NosL Y90A and replacing the substrate amine with a ketone or an alkene changes the chemistry from hydrogen atom abstraction to double bond addition. In addition, the 5'-deoxyadenosyl radical can add to the [4Fe-4S] cluster and dithionite can be used to trap radicals at the active site.

published proceedings

  • J Am Chem Soc

author list (cited authors)

  • Bhandari, D. M., Fedoseyenko, D., & Begley, T. P.

citation count

  • 36

complete list of authors

  • Bhandari, Dhananjay M||Fedoseyenko, Dmytro||Begley, Tadhg P

publication date

  • December 2016