Lanthipeptide engineering: non-canonical amino acids, click chemistry and ring shuffling

Abstract

Antimicrobial resistance is one of the greatest threats to global health nowadays and it has a significant impact on global health and economy throughout the world. Research and development for new technologies to combat antimicrobial resistance are urgently needed. Peptide-based therapeutics have gained greatly increased interest during recent years due to its high selectivity, efficacy, tolerability and excellent safety. Ribosomally synthesized and post-translationally modified peptides (RiPPs) represent an important class of gene-coded peptides with extensive post-translational modifications. Among RiPPs, the class of lanthipeptides represents a rich source for promising leads against Gram-positive bacteria. The unique biosynthetic pathways and relatively low genetic complexity of biosynthesis make lantibiotics good candidates for synthetic biology and bioengineering to expand the antimicrobial arsenal. In this thesis, three different strategies: i) large-scale modular engineering aided by nanoFlaming screening, ii) incorporation of non-canonical amino acids, and iii) chemical coupling were employed to develop novel lantibiotic derivatives. These approaches are able to change the structure and chemical diversity of lanthipeptides and expanded our understanding of structure-activity relationship, and have also led to the development of lantibiotic derivatives with enhanced functionality in terms of activity spectrum, stability and specific activity against clinical relevant antibiotic-resistant pathogens.