Seminar
Topic: ABC Transporters: Structures and Mechanisms
Speaker: Prof. Douglas C. Rees
Division of Chemistry and Chemical Engineering
Howard Hughes Medical Institute
California Institute of Technology
Abstract：
ATP Binding Cassette (ABC) transporters constitute a ubiquitous superfamily of integral membrane proteins responsible for the ATP powered membrane translocation of a wide variety of substrates. The highly conserved ABC domains defining the superfamily provide the nucleotide powered engine that drives transport. In contrast, the transmembrane domains creating the translocation pathway are more variable, with three distinct folds currently recognized. Structural analyses of the high affinity methionine MetNI importer and of a bacterial homologue of the mitochondrial Atm1 exporter will be discussed within the mechanistic framework of the alternating access model. The interconversion of outward and inward facing conformations of the translocation pathway is coupled to the switching between open and closed interfaces of the ABC subunits that are associated with distinct nucleotide states. As observed for MetNI, additional domains may be present that can regulate transport activity. Building on this qualitative molecular framework for deciphering the transport cycle, an important goal is to develop quantitative models that detail the kinetic and molecular mechanisms by which ABC transporters utilize the binding and hydrolysis of ATP to power substrate translocation.
Host: Prof. Yigong Shi
Date: 4:00PM-5:30PM, Nov. 8 (Friday)
Venue: 理学院报告厅（郑裕彤大讲堂）
Welcome!
