The non-Ohmic proton leak--25 years on.
The proton conductance of the mitochondrial inner membrane can be quantified by applying Ohm's law to the experimentally determined protonmotive force and the proton current flowing around the proton circuit in the absence of ATP synthesis or ion transport. This last parameter is derived from the rate of State 4 respiration multiplied by the H+/O stoichiometry for the substrate. When the activity of the dehydrogenase supplying electrons to the respiratory chain is progressively increased the proton conductance increases rapidly when the protonmotive force is greater than 200 mV. The consequences of this non-ohmic relationship are discussed.
Nicholls
D G
DG
Dept of Pharmacology, Ninewells Medical School, University of Dundee, UK.
D000818:Animals; D001692:Biological Transport; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D004553:Electric Conductivity; D008928:Mitochondria / Q000378:metabolism*; D011522:Protons
D011522:Protons