应我院相艳教授邀请,以色列威兹曼科学院Mordechai Sheves教授将来我院进行交流访问,并于5月5日(星期四)上午10:00在为民楼743做报告。欢迎广大师生参加讲座。
题目:Molecular mechanism for the function of retinal proteins
Abstract:Following light absorption, bacteriorhodospin retinal chromophore experiences very large dipolar change in the vertically excited state. Formation of the excited state leads to highly efficient and specific double bond isomerization process, which initiates the pigment photocycle. We have studied the origin of the protein effect on the light-induced dipole and the photochemical isomerization using artificial bacteriorhodopsin pigments derived from synthetic retinal analogs, and Tryptophans modified pigments. The studies demonstrated a significant influence of a protein domain in the vicinity of the retinal ionone ring on the induced dipole and the efficiency of the isomerization process. Fluoro-Tryptophans incorporated into the protein as well as substitution of a specific Tryptophan residue in the ring vicinity significantly lower the quantum yield of the isomerization process.
Prof.Mordechai Shevesreceived both master’s and doctoral degrees in chemistry from the Weizmann Institute. He joined the Institute faculty in 1981, after completing postdoctoral research at Columbia University and, aside from a year’s residence at the University of Illinois as a visiting professor in the Biophysics Department, has been at the Institute ever since. Prof. Sheves is a world leader in the study of photoreceptors (cells in the eye that absorb light) and the molecular processes involved in vision. He served as Head of the Chemical Studies Committee of the Feinberg Graduate School and, more recently, as Head of the Chemical Research Support unit, until his appointment as Dean of the Faculty of Chemistry in 2004. He is the incumbent of the Katzir-Makineni Professorial Chair in Chemistry.