Fig. 1: Chemoenzymatic synthesis of a lariat-shaped peptide using SurE.
From: Non-ribosomal peptide cyclase-directed chemoenzymatic synthesis of lariat lipopeptides
a, Schematic summary of the concepts developed in our previous study44 and this study. b, SurE-mediated cyclization of branched substrate 1 bearing two l-aa nucleophiles at the N terminus and on the side chain as a pseudo-N terminus. The Cα atoms of the terminal d-aa and l-aa are coloured magenta and purple, respectively. c, Chemoenzymatic synthesis of lariat-shaped peptide 5, involving an enzyme-controlled, regiospecific cyclization. d, HPLC analysis of the enzymatic reaction mixture in the SurE-mediated cyclization of 4. Fmoc, 9-fluorenyl-methoxycarbonyl; DMF, N,N-dimethylformamide; Boc, tert-butoxycarbonyl; DIC, diisopropylcarbodiimide.
