An Enzyme that Unties Lasso Peptides

This talk will focus on the discovery and characterization of lasso peptide isopeptidase.  This enzyme is related to prolyl oligopeptidases and cleaves the isopeptide bond in lasso peptides, rendering the peptide linear.  Among the interesting features of this enzyme is that it only recognizes threaded lasso peptides; peptides that have been thermally unthreaded are no longer a substrate for lasso peptide isopeptidase.  I will discuss the substrate promiscuity of the enzyme and its structural characterization.  In addition, I will discuss preliminary work aimed at deciphering the function of lasso peptides associated with the isopeptidase.