Molecule of the Month
December 2012
Electrophysiology Reveals Bacterial Features of the Mitochondrial Outer Membrane Protein Translocase of Trypanosoma brucei

The archaic translocase of the outer mitochondrial membrane (ATOM) from Trypanosoma brucei mediates protein import. Single channel electrophysiology shows that ATOM forms a hydrophilic transmembrane pore with channel characteristics resembling bacterial-type protein translocases. ATOM may therefore represent the missing link between the mitochondrial outer membrane protein import pore and its bacterial ancestors.
Black, single channel trace reveals three equally sized pores. Grey and red, T. brucei and its mitochondrion. Blue, trimeric ATOM in artificial membranes.

This work was carried out by Dr. Anke Harsman in the labs of Prof. Richard Wagner, University of Osnabrück, and Prof. André Schneider, University of Bern.

References:

  • A. Harsman, M. Niemann, M. Pusnik, O. Schmidt, B. M. Burmann, S. Hiller, C. Meisinger, A. Schneider, R. Wagner;
    "Bacterial origin of a mitochondrial outer membrane protein translocase: New perspectives from comparative single channel electrophysiology"
    J. Biol. Chem., 287, 31437-31445, (2012); doi:10.1074/jbc.M112.392118.
    (This article was selected as a paper of the week.)