Molecular Biophysics
Evidence of Distinct Channel Conformations and Substrate Binding Affinities for the Mitochondrial Outer Membrane Protein Translocase Pore Tom40
Background: Nearly all nascent mitochondrial proteins are transported by the translocase of the outer membrane (TOM) complex.Results: The core Tom40 β-barrel domain exhibits four conductive levels and three distinct substrate binding affinities.Conclusion: Tom40 interactions with presequence substrates depend upon the channel's conformation.Significance: Conformational rearrangements in Tom40 may regulate substrate interactions.
