| TCID | Name | Organismal Type | Example |
|---|---|---|---|
| 3.D.3.1.1 | Ubiquinol:cytochrome c oxidoreductase | Bacteria; eukaryotic mitochondria | Cytochrome bc1 complex of Paracoccus denitrificans |
| 3.D.3.2.1 | Ubiquinol:cytochrome c oxidoreductase | Bacteria; eukaryotic mitochondria | Cytochrome bc1 complex of Bos taurus |
| 3.D.3.3.1 | Ubiquinol:cytochrome c oxidoreductase | Bacteria; eukaryotic mitochondria | Cytochrome bc1 complex of Saccharomyces cerevisiae |
| 3.D.3.4.1 | Menaquinone:cytochrome c oxidoreductase | Bacteria | Cytochrome bc1 complex of Bacillus subtilis |
| 3.D.3.5.1 | Plastoquinol:plastocyanine reductase | Eukaryotic chloroplasts; blue-green bacteria; Gram-positive bacteria | Cytochrome b6f complex of Synechocystis PCC6803 |
