Mitochondrial inner membrane oxidative phosphorylation components (OXPHOS)

The mitochondrial inner membrane oxidative phosphorylation (OXPHOS) components comprise a series of five multi-protein complexes (Complexes I, II, III, IV, and V) and mobile electron carriers that facilitate cellular respiration (StatPearls: Mitochondrial Oxidative Phosphorylation). This system is responsible for the majority of adenosine triphosphate (ATP) production in eukaryotic cells by coupling electron transfer to the creation of a proton gradient across the inner mitochondrial membrane (UniProt: OXPHOS components). Beyond its role in bioenergetics, the OXPHOS system is a central hub for metabolic signaling, reactive oxygen species (ROS) generation, and the initiation of programmed cell death. Genetic mutations or environmental insults affecting these components lead to a spectrum of mitochondrial diseases, such as Leigh syndrome and MELAS, and contribute to the progression of neurodegenerative and cardiovascular diseases (NIH: Mitochondrial Diseases). In recent years, OXPHOS has emerged as a therapeutic target in oncology, particularly for tumors that are resistant to conventional therapies or those that rely on mitochondrial metabolism rather than glycolysis (PMID: 30610218). Pharmacological modulation includes the use of biguanides like metformin, which inhibits Complex I, and novel inhibitors designed to disrupt the respiratory chain in specific disease contexts (PMID: 11015482).

Other names

Electron transport chainRespiratory chainMitochondrial respiratory chainOXPHOS system

Inhibition of electron transport chain complexes (I-IV) or ATP synthase (Complex V), leading to decreased ATP production, disruption of the mitochondrial membrane potential, and altered cellular metabolism (PMID: 11015482, PMID: 30610218).