modified from Moran & Scrimgeour Biochemistry 2nd ed. (1994) p 18.8 updated with Matti Saraste "Oxidative Phosphorylation at the fin de siécle " Science 283 (5 March 1999) pp 1488-1492.
| Complex |
MW |
Subunits |
Redox Components |
| I. NADH:ubiquinone (CoQ) oxidoreductase |
900+ kD ( 'L' shaped complex) |
42 or 43 subunits of unknown stoichiometry (25-26 types) |
1 FMN; 7 or 8 different Fe-S centers, covalently bound lipid, 3 or more bound quinols. |
| II. Succinate:ubiquinone (CoQ) reductase |
127 kD (anchored to membrane by b cytochrome) |
4 |
1 FAD; 3 Fe-S clusters; 1 cytochrome b 560 |
| III. CoQ:cytochrome c reductase (Cytochrome bc1) |
280 kD |
11 (only 3 of which have redox centers and bacterial homologs) |
2 cytochrome b; 1 Fe-S cluster; 1 cytochrome c 1 |
| IV. Cytochrome c oxidase |
400 kD |
dimer (13 chains each) |
1 cytochrome a ; 1 CuA; 1 cytochrome a 3; 1 CuB; bound phospholipids |