Yeast-hybrid based high-throughput assay for identification of anthrax lethal factor inhibitors

► A novel yeast-hybrid-based assay system was developed in which the expression of reporter genes from a Gal4 promoter is repressed by anthrax lethal factor (LF) proteolytic activity. ► Yeast cells were co-transformed with LF and a chimeric transcription factor cleaves the substrate, thus inactivating the chimeric Gal4 and resulting in lack of expression of reporter genes. ► Compounds that inhibit LF cleavage of its substrate were identified by changes in reporter gene activity. ► The novel high-throughput screening approach has the advantage of being fast, straight forward, easy and cheap because exogenous LF and substrate are not needed.