A two-step resin based approach to reveal survivin-selective fluorescent probes

The identification of modulators for proteins without assayable biochemical activity remains a challenge in chemical biology. The presented approach adapts a high-throughput fluorescence binding assay and functional chromatography, two protein-resin technologies, enabling the discovery and isolation of fluorescent natural product probes that target proteins independently of biochemical function. The resulting probes also suggest targetable pockets for lead discovery. Using human survivin as a model, we demonstrate this method with the discovery of members of the prodiginine family as fluorescent probes to the cancer target survivin. A dual-resin system was developed that united confocal-fluorescent imaging for hit identification and microscale NMR for hit isolation and structure elucidation. Using this approach, we identified two natural products that bound to the inhibitor of apoptosis protein, survivin.