A CHEMICAL LIGHT SWITCH IN THE VISIBLE RANGE

摘要

Controlling the activity of biomolecules with something as simple, available, and controllable as light is a promising approach with applications in chemotherapy, neuroscience, and biomedical research. However, many existing chemical photoswitches require ultraviolet radiation, which damages cells. Now Emily Que and co-workers introduce a photoswitching system for enzymatic control that can be manipulated with visible light, opening up new possibilities for applications of this technology. They designed two azobenzenesulfonamide molecules that switch from trans to cis conformation at certain visible wavelengths, thanks to fluorination of positions ortho to the azo group. The trans isomer of the molecules targets the active site of carbonic anhydrase and strongly inhibits the enzyme. The cis isomer has much weaker interaction with the enzyme and thus inhibits the enzyme less effectively. The researchers show that the fluorinated probes control the enzyme's activity in solution, in live cells, and in live zebrafish during embryonic development.