This is a ribbon structure of cytochrome oxidase
, also known as complex IV. This is the terminal, or final, enzyme of the electron transport system (not including ATP synthase). Cytochrome oxidase is a transmembrane molecule found in the mitochondria of eukaryotes and in the cellular space of aerobic prokaryotes. This molecule is a proton pump that plays a vital role in producing energy, in the form of ATP, via the electron transport system. This structure was created from PDB 1OCC.