John E. Walker

For more than 20 years, John Walker has been engaged in studies of the mechanism of ATP synthases from bovine heart mitochondria and eubacteria. His work has led to the demonstration that these enzymes have a rotary mechanism. Currently, he and his colleagues are studying how rotation is generated from the transmembrane proton motive force. He and his colleagues have also worked on other vital proteins in mammalian mitochondria. They have analysed the organisation of complex I (NADH:ubiquinone oxidoreductase), one of the most complicated enzymes known, and they have identified membrane proteins that transport essential substrates, metabolites and co-factors in and out of mitochondria.