Research Interests: Mechanism of Actin-Based Motility
Ph.D. from Iowa State University, 1973
Office: R3-126 ARB
Lab: R3-171 ARB
Telephone: (352) 294-8400
Dr. Purich earned his Ph.D. for investigating brain hexokinase kinetics and regulation under Herbert Fromm at Iowa State University. A Staff Research Fellow under Earl Stadtman at the NIH, he elucidated the enzyme nucleotidylation cascade controlling bacterial glutamine synthetase. Purich joined the University of California Santa Barbara Department of Chemistry in 1973, and rose through the ranks to full professor in 1982. While at UCSB, he was awarded an A. P. Sloan Award, the. Plous campus-wide teaching award, and an NIH Research Career Development Award. In 1984, he became Chairman of Biochemistry & Molecular Biology here and resumed full-time professorial activities in 1996. Dr. Purich served on the editorial boards of Journal of Biological Chemistry and Archives of Biochemistry & Biophysics, served on the NIH Biochemistry Study Section, and edited the six-volume Enzyme Kinetics & Mechanism series in Methods in Enzymology, as well as Contemporary Enzyme Kinetics & Mechanism. Dr. Purich is the lead author of The Handbook of Biochemical Kinetics (2000), The Enzyme Reference (2002), and Enzyme Kinetics: Catalysis & Control (2010).
Molecular Motors in Actin-Based Motility
A specialist in enzyme chemistry and cell motility, Dr. Purich has published over 150 papers, chapters, and review articles on the mechanisms of action of enzymes, microtubules, and actin filaments. To account for noncovalent substrate- and product-like states of mechanoenzyme reactions (e.g., State1 + ATP = State2 + ADP + Pi), he redefined enzyme catalysis as the facilitated making/breaking of chemical bonds – not just covalent bonds. He also coined the term energase to signify those energy-driven enzymes (e.g., molecular motors, active transporters, translocators, GTPregulatory proteins, ribosomes, etc.) comprising a hitherto unrecognized seventh and distinct class of enzyme-catalyzed reactions. He and UF colleague Richard Dickinson co-discovered actoclampin, an entirely novel class of molecular motors that harness the Gibbs energy of ATP hydrolysis as they track along actin filament (+)-ends and generate the substantial forces needed for amoeboid-like cell crawling, endosome and phagosome motility, as well as dendritic spine remodeling into functional synapses