part of oxidative phosphorylation uncoupler activity GO:0015302 uncoupling protein activity Enables the transfer of protons from mitochondrial intermembrane space into mitochondrial matrix, dissipating the proton gradient across the mitochondrial inner membrane established by the electron transport chain during the oxidative phosphorylation (proton leak). Proton leak uncouples the processes of electron transport/proton generation and ATP synthesis. GO:0017077 mitochondrial uncoupling protein activity molecular_function transmembrane transporter activity proton transmembrane transport