Blue Light-Induced Dimerization of a Bacterial LOV-HTH DNA-Binding Protein

With their utilization of light-driven allostery to control biochemical activities, photosensory proteins are of great interest as model systems and novel reagents for use by the basic science and engineering communities. One such protein, the light-activated EL222 transcription factor, from the marine bacterium Erythrobacter litoralis HTCC2594, is appealing for such studies, as it harnesses blue light to drive the reorientation of light-xygen voltage (LOV) sensory and helix-turn-helix (HTH) effector domains to allow photoactivation of gene transcription in natural and artificial systems.