Friday, November 18, 2016

Tasting Light: New Type of Photoreceptor is 50 Times More Efficient than the Human Eye

A new type of receptor, 50 times more efficient at capturing light than the rhodospin in the human eye, was discovered among a family of taste receptors in roundworms.  This new receptor protein has unique properties that suggest potential future applications.  LITE-1 is extremely efficient at absorbing UV-A and UV-B light.  It is 10 - 100 times greater than opsins and cryptochromes.  The genetic code of these receptor proteins is far different from other types of photoreceptors found in plants, animals and microbes.  The chromophore in animal receptors retains some functionality when broken apart, but LITE-1 completely loses its ability to absorb light when denatured.  Scientists determined that having the tryptophan in two places was critical to the function of the protein.  They modified a nonlight-sensitive protein, GUR-3, with tryptophan and it reacted to UV light with a third the sensitivity to UV-B as LITE-1.  Scientists may be able to genetically engineer other photoreceptors.

No comments:

Post a Comment