Targeted discovery of polycyclic tetramate macrolactams from an environmental Streptomyces strain.

A targeted polymerase chain reaction (PCR)-based screening approach was used to identify candidate polycyclic tetramate macrolactam (PTM) biosynthetic gene clusters in environmental Streptomyces isolates. Isolation and characterization of the small molecules produced by one of the strains confirmed the production of two new PTMs (clifednamides A, 4, and B, 5) and, more generally, the utility of using a targeted approach for the discovery of new members of this interesting class.