Dr. Sergei Sukharev
Department of Biology
University of Maryland
College Park, MD

Monday, November 8, 2004
3:00 pm (CT)
3269 Beckman Institute

Abstract

Mechanosensitive channels MscL and MscS are tension-driven release valves involved in turgor pressure regulation in essentially all bacteria. At the same time, they are convenient model systems for basic studies of channel gating driven by membrane tension. I will present a coherent picture of the gating mechanism of MscL which includes thermodynamic and kinetic analyses, molecular model of the transition process and supporting disulfide cross-linking data. Additional analysis of gain-of-function mutants will be presented in the context of the gating model involving a critical process of pore hydration. In the second part I will present the gating phenomenology of MscS with its characteristic voltage- and tension-dependent inactivation. The functional data will be reconciled with the available structural information in a molecular model of the MscS gating process.

Tea and coffee will be served in R3151 Beckman Institute at 2:15pm.