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

Abstract

Enediyne antibiotics are a striking family of DNAcleaving natural products with high degrees of cytotoxicity and structural complexity. Microbial genome sequences, which have recently accumulated, point to an untapped trove of "cryptic" enediynes. Most of the cognate biosynthetic gene clusters (BGCs) are sparingly expressed under standard growth conditions, making it difficult to characterize their products. Herein, we report a fluorescence-based DNA cleavage assay coupled with highthroughput elicitor screening for the rapid, targeted discovery of cryptic enediyne metabolites. We applied the approach to Streptomyces clavuligerus, which harbors two such BGCs with unknown products, identified steroids as effective elicitors, and characterized 10 cryptic enediyne-derived natural products, termed clavulynes A−J with unusual carbonate and terminal olefin functionalities, with one of these congeners matching the recently reported jejucarboside. Our results contribute to the growing repertoire of enediynes and provide a blueprint for identifying additional ones in the future.

Characterization of Chemical Interactions between Clinical Drugs and the Oral Bacterium, Corynebacterium matruchotii, via Bioactivity-HiTES

“…We also unexpectedly found the biotransformation of the anticancer drug FDP ( 2 ) to F-Ade ( 6 ), which showed significant antibacterial activity, while the original drug did not. This result indicates a broader application of the HiTES method to find biotransformed products as well as cryptic metabolites from microorganisms. − ,− …”

Methodology for awakening the potential secondary metabolic capacity in actinomycetes

“…Seyedsayamdost et al developed the high-throughput elicitor screening (HiTES) approach, a forward chemical genetics method that identifies small-molecule inducers of silent natural products ( Figure 2e ) [ 49 ]. Han et al applied a fluorescence-based DNA cleavage assay coupled with HiTES to Streptomyces clavuligerus and identified the steroid 11α-hydroxyprogesterone ( 14 ) as an effective elicitor and characterized 10 cryptic enediyne-derived natural products, designated clavulynes A ( 15 ) and B–J with unusual carbonate and terminal olefin functionalities [ 50 ]. Thus, artificial methods of genetic engineering and chemistry also play an important role in the identification of novel secondary metabolites.…”