Hydrophobic gating of mechanosensitive channel of large conductance evidenced by single-subunit resolution.

ABSTRACT: Mechanosensitive (MS) ion channels are membrane proteins that detect and respond to membrane tension in all branches of life. In bacteria, MS channels prevent cells from lysing upon sudden hypoosmotic shock by opening and releasing solutes and water. Despite the importance of MS channels and ongoing efforts to explain their functioning, the molecular mechanism of MS channel gating remains elusive and controversial. Here we report a method that allows single-subunit resolution for manipulating and monitoring "mechanosensitive channel of large conductance" from Escherichia coli. We gradually changed the hydrophobicity of the pore constriction in this homopentameric protein by modifying a critical pore residue one subunit at a time. Our experimental results suggest that both channel opening a

SUBMITTER: Birkner JP 

PROVIDER: S-EPMC3420157 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature