INTERACTION OF CARBONYL CYANIDE 3-CHLOROPHENYLHYDRAZONE WITH CYTOCHROME-C-OXIDASE

Cytochrome c oxidase binds protonophore carbonyl cyanide 3-chloropheny lhydrazone (CCP) with high affinity. There are 1.46 high-affinity bind ing sites per cytochrome c oxidase for CCCP with dissociation constant 2.7. 10(-7) mol/l. The bond between the CCCP and cytochrome c oxidase accomplishes through the group on cytochrome c oxidase with pK(a), 6. 64 and is based on the electrostatic interaction. Interaction of CCCP with low-affinity binding sites of cytochrome c oxidase induces the sh ift of the anion CCCP spectrum to UV-region. The similar effect is cha racteristic for CCCP interaction with protons. Lipophilic non-dissocia ted derivative NCH3CCP is not binding to cytochrome c oxidase.