Related Experiment Video
Updated: Jun 6, 2026

Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
Tight control of mitochondrial membrane potential by cytochrome c oxidase
Consiglia Pacelli1, Dominga Latorre, Tiziana Cocco
1Department of Medical Biochemistry, Biology and Physics, University of Bari, Bari, Italy.
Abstract:
In the present work we have critically examined the use of the KCN-titration technique in the study of the control of the cellular respiration by cytochrome c oxidase (COX) in the presence of the mitochondrial membrane potential (Δψ(mito)) in HepG2 cells. We clearly show that the apparent high inhibition threshold of COX in the presence of maximal Δψ(mito) is due to the KCN-induced decrease of Δψ(mito) and not to a low control of COX on the mitochondrial respiration. The tight control exerted by COX on the Δψ(mito) provides further insights for understanding the pathogenetic mechanisms associated with mitochondrial defects in human neuromuscular degenerative disorders.
Related Concept Videos
The Inner Mitochondrial Membrane
Mitochondrial Membranes
Mitochondrial Membranes
The Electron Transport Chain
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Electron Transport Chain: Complex III and IV
The Supercomplexes in the Crista Membrane

