Figure 2.

A) MPyE‐induced ligation between peptide thioesters 28Z and peptides 27X (letters Z and X represent amino acids specified in the Figure legend, R=(CH₂)₂CONHCH₂CONH₂). Representative UPLC analysis for the ligation of peptides 27V and 28A B) at t=1 min, C) after t=24 h and treatment with hydrazine (2.5 %). D) Time course of ligation at different junctions. Conditions: 5 mM peptides, 20 mM TCEP, 200 mM Na₂HPO₄, 6 M Gdn‐HCl, 3 vol. % PhSH, rt, pH 7.5.