description | Protein which interacts with ubiquinone. This fat soluble benzoquinone has a long isoprenoid side chain, which varies in length depending on the species. For example, S.cerevisiae has CoQ-6, E.coli has CoQ-8, rat and R.capsulatus have CoQ-9 and S.pombe, G.suboxydans and humans have CoQ-10. Ubiquinone is a carrier of hydrogen atoms (protons plus electrons) and functions as an ubiquitous coenzyme in redox reactions, where it is first reduced to the enzyme-bound intermediate radical semiquinone and in a second reduction to ubiquinol (Dihydroquinone; CoQH2). Ubiquinone is not tightly bound or covalently linked to a protein complex but is very mobile |