Figure 39.

Conformational selection model whereby leader peptide binding shifts an equilibrium to an active enzyme state that promotes core peptide binding to the enzyme and facilitates catalysis. The enzyme, leader peptide, and core peptide are shown in blue, pink, and green, respectively. The leader peptide in class II LanAs is predicted to form a helix but this conformation has not been directly proven in the context of interactions with the modifying enzymes and is not generalizable to class I lanthipeptide biosynthesis, as the precursor NisA does not adopt a helical conformation in binding to its modifying enzyme NisB (section 2.5).