Directed Evolution of the Nonribosomal Peptide Synthetase AdmK Generates New Andrimid Derivatives In Vivo

Many lead compounds in the search for new drugs derive from peptides and polyketides whose similar biosynthetic enzymes have been difficult to engineer for production of new derivatives. Problems with generating multiple analogs in a single experiment along with lack of high-throughput methods for structure-based screening have slowed progress inthis area.

However, by using directed evolution and a multiplexed assay to screen a library of >14,000 members, it is able to generate three derivatives of the antibacterial compound, andrimid. Since another limiting factor in reengineering these mega-enzymes of secondary metabolism has been that commonly used hosts such as Escherichia coli often give lower product titers. However, in this study, reengineering was performed in the native producer, Pantoea agglomerans. This integrated in vivo approach can be extended to larger enzymes to create analogs of natural products for bioactivity testing.