Chemist John D. Roberts of Altadena, Calif., will be honored April 3 by the world's largest scientific society for his pioneering studies in technology to better understand molecules important to life. He will receive the 2001 Nakanishi Prize from the American Chemical Society at its 221st national meeting in San Diego.
"Over the last quite a few years, my research group and I have found out much about the structures of molecules and how they work - particularly in biochemical processes," said Roberts, who is professor emeritus of chemistry at the California Institute of Technology, Pasadena.
One of his projects has been studying the action of a class of protein enzymes called proteases, the body's scissors. Despite their role in diseases such as AIDS, proteases also snip up food proteins during digestion and perform other processes critical to life.
The research tool Roberts uses is called nuclear magnetic resonance, for whose development colleagues call him a pioneer in the field. NMR is based on the principle that nuclei - those of carbon, nitrogen and so on - will vibrate at some unique frequency when placed in an energy field. Researchers use NMR to identify and analyze compounds.
Specifically, Roberts used NMR in the 1970s to learn more about why proteases are able to cut up other proteins without cutting up themselves. While many proteins fit into the protease active site, where cleavage takes place, the simple answer is that proteases do not.
But his team uncovered important details: "We showed the way in which three protease amino acids [protein subunits] in particular cooperate with each other to attack the bonds," he said, and at the same time disproved a then-popular theory of action.
Roberts continues active research despite retiring officially in 1988. He and his students are now using NMR to study "how and why certain arrangements of molecules are more favorable than others," he said.