A radical SAM (S-adenosylmethionine-cleaving) enzyme cyclizes the chain, forming the new cross-link. Afterward, the peptide is trimmed to a 9-mer. “The radical SAM enzyme that makes the cross-link is very interesting,” says Wilfred A. van der Donk, a chemistry professor at the University of Illinois, Urbana-Champaign, who studies macrocyclic peptides. “New cyclization strategies can represent powerful new methodology in the toolbox for making cyclic peptides, provided the enzyme has tolerance for different peptide sequences.” “Adding this chemotype to the bestiary of known, naturally occurring macrocyclic peptides is highly valuable,” says Adrian Whitty, a chemistry professor at Boston University who studies synthetic macrocycles.
by Celia Henry Arnaud |
April 23, 2015