Light-Controlled Chemical Reactions and Their Applications in Biological Systems

Light has long been used as an external signal to control biological systems. The ability to control chemical reactions with a light stimulus has led to advances in the use of optical techniques for the precise control of biological systems. In particular, light can be used to reversibly control biological processes via photoisomerization of light-responsive molecules. This Focus Review discusses recent developments of novel light-controlled compounds including photoresponsive drugs, red light-shifted azobenzene photoswitches, and synthetic chromophores of fluorescent proteins with new spectroscopic characteristics.