The MARC Program has invited Dr. Daniel Oprian to share his lecture, "Probing Terpene Synthase Reaction Mechanisms with Fluorinated Substrate Analogs." Dr. Daniel Oprian is a Louis and Bessie Rosenfield Professor of Biochemistry at Brandeis. He has worked with visual pigments for 35 years. Much of that time was devoted to a mutagenesis approach to understanding the structure and function of rhodopsin and the color vision pigments. In 2003/04, he spent a very successful year on sabbatical leave in Gebhard Schertler’s laboratory in Cambridge, UK learning to become a crystallographer. That year resulted in an X-ray crystal structure of the first recombinant GPCR, a thermally stable mutant of rhodopsin, opening the doors for a serious structural attack on the numerous functional mutants he had been studying for years. Since that time they have published two more structures of rhodopsin, both constitutively active mutants in an active state, and four structures of recoverin. Dr. Oprian and his colleagues continue studies of the structure and mechanism of rhodopsin as well as studies of downstream signaling complexes involving transducin, rhodopsin kinase, arrestin and recoverin.

More recently, Dr. Oprian has begun working in two new areas:  enzyme-linked rhodopsins and terpene synthases.  The work on terpene synthases includes time-dependent X-ray crystallography of intermediates along the reaction coordinate for the reaction catalyzed by the enzyme limonene synthase.