Allosteric nucleotide-binding site in the mitochondrial NADH:ubiquinone oxidoreductase (respiratory complex I)

► Mitochondrial respiratory complex I binds purine nucleotides at allosteric site. ► ATP binding stimulates NADH: hexaammineruthenium(III) reductase activity. ► Prokaryotic homologue of complex I lacks of allosteric ATP-binding site.