Sequence, structure and activity of phosphoglycerate kinase: a possible hinge-bending enzyme

The fitting of sequenced peptides to a high-resolution X-ray map of phosphoglycerate kinase has yielded the complete sequence and structure of the horse muscle enzyme. Metal ADP and ATP substrates are bound to one of the two widely separated domains in an environment that seems unsuitable for phosphoglycerate binding. The most plausible binding site for the phosphoglycerate substrate is on the other domain about 10 A from the ATP, which implies the possibility of a large scale hinge-bending of the domains to bring the two substrates together in a water-free environment for catalysis.