Jeremy Randall Knowles was a professor of chemistry at Harvard University,who served as dean of the Harvard University faculty of arts and sciences from 1991 to 2002. He joined Harvard in 1974, received many awards for his research, and remained at Harvard until his death, leaving the faculty for a decade to serve as Dean. Knowles died on 3 April 2008 at his home. In 2006, he was selected by incoming interim president Derek Bok to return to his position as Dean of the Faculty of Arts and Sciences on an interim basis, replacing William C. Kirby, who was ousted by now former president Lawrence Summers.
In 1961, he took a post-doctoral fellowship at the California Institute of Technology, working with George S. Hammond, who was an organic photo-chemist. Together, they found that some catalyzed reactions can occur up to one-million times faster than non-catalyzed reactions. Intrigued by this discovery, Knowles became an enzymologist. For a brief time, Knowles was a visiting professor at Yale University. in 1974, Knowles moved his research group to Harvard and became a professor there. Knowles's research was on the boundary of chemistry and biochemistry, and concerned the rate and specificity of enzyme catalysis and the evolution of enzyme function. Early in his career, Knowles studied α-chymotrypsin and pepsin, which are nonspecific proteases, meaning they accept a broad range of substrates. He researched what made these enzymes nonspecific and how they increased the rate of peptide-bond hydrolysis. In 1972, Knowles developed a method for photo-affinity labelling, enabling the formation of a covalent bond between a protein and a ligand under the control of light. Knowles then began seminal studies on the glycolytic enzyme triosephosphate isomerase. He took advantage of its simplicity—interconverting a single substrate and a single product. Using the enediol intermediate of the reaction and kinetic isotope effects, he measured the relative free energy of each intermediate and transition state, which allowed him to depict the first free energy profile for an enzyme-catalyzed reaction. This work was done with his long-term collaborator, John Albery. His profile showed that TIM was a "perfect" enzyme in that catalysis is limited only by the rate of diffusion. Later, Knowles applied similar methods to proline racemase, developing an elegant method to discern whether a reaction proceeds via a stepwise or concerted manner and discovering the consequences of "oversaturation", a situation in which the interconversion of unliganded forms of the enzyme limit catalysis. At Harvard, Knowles also did important work on β-lactamases and their mechanism-based inhibitors. And, he provided key insight on the stereochemistry of phosphoryl group transfer reactions, using synthetic phosphoryl groups containing 16O, 17O, and 18O isotopes. Knowles was the author of more than 250 research papers, and advised more than 50 DPhil recipients at Oxford and at Harvard, including Hagan Bayley, Stephen L. Buchwald, and Ronald T. Raines.
