{'Entry': 'Q33887', 'Protein names': 'Cytochrome b (Complex III subunit 3) (Complex III subunit III) (Cytochrome b-c1 complex subunit 3) (Ubiquinol-cytochrome-c reductase complex cytochrome b subunit)', 'Function': 'Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex) that is part of the mitochondrial respiratory chain. The b-c1 complex mediates electron transfer from ubiquinol to cytochrome c. Contributes to the generation of a proton gradient across the mitochondrial membrane that is then used for ATP synthesis. {ECO:0000250|UniProtKB:P00157}.', 'Subunit structure': 'SUBUNIT: The cytochrome bc1 complex contains 11 subunits: 3 respiratory subunits (MT-CYB, CYC1 and UQCRFS1), 2 core proteins (UQCRC1 and UQCRC2) and 6 low-molecular weight proteins (UQCRH/QCR6, UQCRB/QCR7, UQCRQ/QCR8, UQCR10/QCR9, UQCR11/QCR10 and a cleavage product of UQCRFS1). This cytochrome bc1 complex then forms a dimer. {ECO:0000250|UniProtKB:P00157}.', 'Tissue specificity': '', 'Temperature dependence': '', 'pH dependence': '', 'Catalytic activity': '', 'Organism': 'Akodon toba (Chaco grass mouse)', 'Involvement in disease': '', 'Induction': ''}