Exploring O2 diffusion in A-type cytochrome c oxidases: molecular dynamics simulations uncover two alternative channels towards the binuclear site.
Cytochrome c oxidases (Ccoxs) are the terminal enzymes of the respiratory chain in mitochondria and most bacteria.These enzymes couple dioxygen (O2) reduction to the generation of a transmembrane electrochemical proton gradient.Despite decades of research and the availability of a large amount of structural and biochemical data available for the A-