Structural Basis for the N-Terminal Capping onto the Ribosomal Peptide by Novel Peptide Ligase PGM1

Abstract

Pheganomycins（PGMs）derived from Streptomyces cirratus are one of the peptide antibiotics and synthesized under the cooperation of a novel peptide ligase, PGM1, and ribosome, in contrast of typical peptide antibiotics. In the biosynthesis, PGM1, which is a peptide ligase with broad substrate permissivity, can catalyze the linkage between several types of nonproteinogenic amino acid including a 2-guanidino group and some ribosomal peptides to generate N-terminal capping peptide. Herein, I present structural studies for the recognition mechanisms of N-terminal capping substrates and C-terminal ribosomal peptides.