Susanna E. Barrett

Abstract Ribosomally synthesized and post-translationally modified peptides (RiPPs) comprise a structurally and functionally diverse group of natural products. Lasso peptides represent one of about 50 known molecular classes of RiPPs, which display a characteristic [1]rotaxane conformation formed by a lasso cyclase. This unique, threaded conformation endows lasso peptides with diverse biological activities and remarkable thermal and proteolytic stability.

Abstract Lasso peptides are a diverse class of naturally occurring, highly stable molecules kinetically trapped in a distinctive [1]rotaxane conformation. How the ATP-dependent lasso cyclase constrains a relatively unstructured substrate peptide into a low entropy product has remained a mystery owing to poor enzyme stability and activity in vitro.