Presentation description

Radical S-adenosyl-L-methionine (rSAM) enzymes are a superfamily of enzymes capable of catalyzing natural product reactions involving radical intermediates. Computational analysis of PapB, an rSAM enzyme found in nature, reveals two protein regions with distinct potential functions. In vitro experiments have shown catalytic conversion of the substrate even when the RiPP Recognition Element (RRE) is removed from the enzyme. The binding affinities of PapB-RRE to various substrate mutations of PapA were measured using isothermal titration calorimetry (ITC), showing no significant differences when individual residues were substituted with alanine. This suggests a lack of specific residue interactions. These results demonstrate the promiscuity of PapB, highlighting its potential for versatile use in synthesizing modified peptides from a variety of substrates.