Coupling of proton and substrate translocation in the transport cycle of mitochondrial carriers.
Members of the mitochondrial carrier family are involved in transporting keto acids, amino acids, nucleotides, inorganic ions and co-factors across the mitochondrial inner membrane. The transporters are thought to share the same structural fold, which consists of six trans-membrane alpha-helices and three matrix helices, arranged with threefold pseudo-symmetry. During the transport cycle two salt bridge networks on either side of the central cavity might regulate access to a single substrate binding site in an alternating fashion. In the case of proton-substrate symporters the substrate binding sites contain also negatively charged residues that are proposed to be involved in proton transport.
Kunji
Edmund R S
ER
The Medical Research Council, Mitochondrial Biology Unit, Hills Road, Cambridge CB2 0XY, United Kingdom. ek@mrc-mbu.cam.ac.uk
Robinson
Alan J
AJ
D000818:Animals; D001665:Binding Sites; D001692:Biological Transport; D006801:Humans; D033681:Mitochondrial Membrane Transport Proteins / Q000737:chemistry / Q000378:metabolism*; D011522:Protons
D033681:Mitochondrial Membrane Transport Proteins; D011522:Protons