Interaction of the Mechanosensitive Channel, MscS, with the Membrane Bilayer through Lipid Intercalation into Grooves and Pockets.

ABSTRACT: All membrane proteins have dynamic and intimate relationships with the lipids of the bilayer that may determine their activity. Mechanosensitive channels sense tension through their interaction with the lipids of the membrane. We have proposed a mechanism for the bacterial channel of small conductance, MscS, that envisages variable occupancy of pockets in the channel by lipid chains. Here, we analyze protein-lipid interactions for MscS by quenching of tryptophan fluorescence with brominated lipids. By this strategy, we define the limits of the bilayer for TM1, which is the most lipid exposed helix of this protein. In addition, we show that residues deep in the pockets, created by the oligomeric assembly, interact with lipid chains. On the cytoplasmic side, lipids penetrate as far as the po

SUBMITTER: Rasmussen T 

PROVIDER: S-EPMC6787928 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature