COX4I1 Protein, Human (His-SUMO)

COX4I1, a vital constituent of the cytochrome c oxidase, serves as a pivotal component in the mitochondrial electron transport chain, culminating in oxidative phosphorylation. This respiratory chain encompasses three multisubunit complexes—succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII), and cytochrome c oxidase (complex IV, CIV)—that collaboratively facilitate the transfer of electrons from NADH and succinate to molecular oxygen. This intricate process generates an electrochemical gradient across the inner membrane, propelling transmembrane transport and fueling ATP synthase. Specifically, cytochrome c oxidase orchestrates the reduction of oxygen to water. The electron transfer from reduced cytochrome c in the intermembrane space involves intermediates, such as the dinuclear copper A center (CU(A)) in subunit 2 and heme A in subunit 1, ultimately converging at the active site in subunit 1—a binuclear center (BNC) comprised of heme A3 and copper B (CU(B)). The BNC efficiently reduces molecular oxygen to two water molecules, utilizing four electrons from cytochrome c in the intermembrane space and four protons from the mitochondrial matrix. COX4I1 thus plays a central role in energy metabolism, contributing to the intricate processes of oxidative phosphorylation.