Cacaoidin, First Member of the New Lanthidin RiPP Family
Francisco Javier Ortiz‐López, Daniel Carretero‐Molina, Marina Sánchez‐Hidalgo, Jesús Martı́n, Ignacio González, Fernando Román‐Hurtado, Mercedes de la Cruz, Sergio García‐Fernández, Fernando Reyes, Julia P. Deisinger, Anna Müller, Tanja Schneider, Olga Genilloud
Abstract
Lantibiotics are ribosomally synthesized and post-translationally modified peptides (RiPPs) characterized by the presence of lanthionine or methyllanthionine rings and their antimicrobial activity. Cacaoidin, a novel glycosylated lantibiotic, was isolated from a Streptomyces cacaoi strain and fully characterized by NMR, mass spectrometry, chemical derivatization approaches and genome analysis. The new molecule combines outstanding structural features, such as a high number of d-amino acids, an uncommon glycosylated tyrosine residue and an unprecedented N,N-dimethyl lanthionine. This latter feature places cacaoidin within a new RiPP family located between lanthipeptides and linaridins, here termed lanthidins. Cacaoidin displayed potent antibacterial activity against Gram-positive pathogens including Clostridium difficile. The biosynthetic gene cluster showed low homology with those of other known lanthipeptides or linaridins, suggesting a new RiPP biosynthetic pathway.