| 1 | Name: | Dr. Jack E. Dixon | |
| Institution: | University of California, San Diego | ||
| Year Elected: | 2010 | ||
| Class: | 2. Biological Sciences | ||
| Subdivision: | 201. Molecular Biology and Biochemistry | ||
| Residency: | Resident | ||
| Living? : | Living | ||
| Birth Date: | 1943 | ||
Jack E. Dixon is a leading American biochemist, born in Nashville, Tennessee on June 16, 1943. He is currently Professor Emeritus of Pharmacology, Cellular & Molecular Medicine, and Chemistry & Biochemistry at the University of California, San Diego. He also served as Vice President and Chief Scientific Officer from 2007 to 2013. Dixon's laboratory has pioneered the study of protein tyrosine phosphatases (PTPases), the enzymes that remove phosphate from proteins. His work on the catalytic mechanism of these enzymes included the demonstration that they function via a novel cysteine-phosphate intermediate. In an unexpected development, Dixon also showed that the bacterium responsible for the plague or "black death", Yersinia pestis, harbors the most active PTPase ever described. Dixon, in collaboration with Stanley Falkow, went on to demonstrate that this PTPase is essential for pathogenesis. In fact, this PTPase functions as a "lethal weapon" which is "injected" into mammalian cells to block the immune response. This was the first conclusive demonstration of a widely used strategy for pathogenic bacteria to disarm the host immune system. Dixon's interest in phosphatases led his laboratory to determine the function of the tumor suppressor protein, PTEN, which shares sequence identity with the PTPases. Although most PTPases function to dephosphorylate phosphoproteins, PTEN dephosphorylates a lipid, phosphatidylinositol-3,4,5-triphosphate (PIP33). The loss of the PTEN gene elevates PIP3 levels causing cells to survive and become oncogenic. The insightful determination of how PTEN functions has radically altered thinking about this tumor suppressor gene. Jack Dixon has received numerous awards including the Michigan Scientist of the Year, the William Rose and Merck Award from the American Society of Biochemistry and Molecular Biology. He is a member of the National Academy of Sciences, the Institute of Medicine and the American Academy of Arts and Sciences. Jack Dixon is married to Claudia M. Kent, a retired professor of Biological Chemistry. Dr. Kent is a fellow of the American Association for the Advancement of Science. | |||