Structure of bovine cytochrome c oxidase in the ligand-free reduced state at neutral pH.

ABSTRACT: Cytochrome c oxidase (CcO), the terminal oxidase in cellular respiration, couples proton pumping to O₂ reduction. Mammalian CcO resides in the inner mitochondrial membrane. Previously, a model of H-pathway proton pumping was proposed based on various CcO crystal structures. However, all previously determined structures were solved using crystals obtained at pH 5.7, which differs from the environmental pH of CcO in the inner membrane. The structures of fully oxidized and ligand-free reduced CcO at pH 7.3 have now been determined. Structural comparison between the oxidized and reduced states revealed that the structural alterations that occurred upon redox change at pH 5.7 in Asp51, the magnesium-containing cluster, haem groups and helix X, which provide important structural evide

SUBMITTER: Luo F 

PROVIDER: S-EPMC5947679 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature