Stamp of Approval

On a recent trip to accept an honorary doctorate from his alma mater, Technion-Israel Institute of Technology, Nobel Laureate Arieh Warshel was also honored with a commemorative Israeli postage stamp.

The imprint, which celebrates the United Nations (UN) 2015 International Year of Light, was dedicated to the three 2013 Nobel Prize laureates in chemistry: Warshel, Distinguished Professor of Chemistry, Biological Sciences, Biochemistry, and Chemical Engineering and Materials Science at USC Dornsife, and Martin Karplus and Michael Levitt. It will be officially released Oct. 10.

One of the most important achievements of these Nobel laureates’ work is the molecular dynamics simulations of biological processes, which provide a computerized description of actual events that occur in nature. Among the earliest and most significant examples of this strategy is the deciphering of the precise molecular dynamics that occur during the process of vision. Warshel was the key researcher who deciphered the role of the protein rhodopsin, the biological pigment in retina cells.

The right side of the stamp features rhodopsin, a bundle of seven helices connected to each other by peptide loops. The protein is embedded within the cell membrane and binds a small, light-sensitive molecule called retinal, shown as a group of grey spheres on the stamp.

“It is an interesting selection since the year of the light has largely been adopted by physicists in view of the great impact of lasers,” said Warshel. “However, photochemistry and photobiology reflect the relationship between light and life. I am delighted to see that they chose to depict rhodopsin on the stamp.”

Warshel’s research on rhodopsin represents one of his most important scientific contributions, his prediction in 1976 of what transpires in the first picosecond after light strikes the eye. The corresponding simulation of this event was also the first molecular dynamics simulation of a biological process, Warshel said.

“I would have been equally pleased if they had chosen photosynthesis,” another biological process in which he made pioneering contributions, he added.