Jones group publication
Jones group publishes the first photochemical mechanism of a B12-dependent photoreceptor protein in Nature Communications.
Coenzyme B12 chemistry is considered synonymous with radical mechanism. It acts as a latent source of radicals to enzymes that facilitate important metabolic processes in both bacteria and humans, and B12 photolysis generates that same radical pair as the activated enzyme. For many years, however, B12 photochemistry was thought to serve no biological purpose.
It was recently discovered that the bacterial photoreceptor, CarH, required B12 to effect light-dependent regulation of the genes that result in carotenoid synthesis in response to photo-oxidative stress. Alex’s group, in collaboration with Perdita Barran and scientists in Spain, described the first detailed mechanism for a B12-dependent photoreceptor protein. This mechanism is independent of the radical mechanism so closely associated with B12, and therefore represents not only a mechanistic foundation for B12 photobiology but also new chemistry for a B12 molecule.