Targeted Discovery of Cryptic Enediyne Natural Products via FRET-Coupled High-Throughput Elicitor Screening

Enediyne antibiotics are a striking family of DNA-cleavingnaturalproducts with high degrees of cytotoxicity and structural complexity.Microbial genome sequences, which have recently accumulated, pointto an untapped trove of cryptic enediynes. Most ofthe cognate biosynthetic gene clusters (BGCs) are sparingly expressedunder standard growth conditions, making it difficult to characterizetheir products. Herein, we report a fluorescence-based DNA cleavageassay coupled with high-throughput elicitor screening for the rapid,targeted discovery of cryptic enediyne metabolites. We applied theapproach to Streptomyces clavuligerus, which harbors two such BGCs with unknown products, identified steroidsas effective elicitors, and characterized 10 cryptic enediyne-derivednatural products, termed clavulynes A-J with unusual carbonateand terminal olefin functionalities, with one of these congeners matchingthe recently reported jejucarboside. Our results contribute to thegrowing repertoire of enediynes and provide a blueprint for identifyingadditional ones in the future.

Automated summary

Researchers have discovered new antibiotics and metabolites in previously unexplored Streptomyces clavuligerus strains using a fluorescence-based DNA cleavage assay and high-throughput elicitor screening. These compounds, called clavulynes A-J, have unique carbonate and terminal olefin functionalities, and contribute to the growing repertoire of enediynes.