Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Cofactor-independent phosphoglycerate mutase (iPGM), an important enzyme in glycolysis and gluconeogenesis, catalyses the isomerization of 2- and 3-phosphoglycerates by an Mn(2+)-dependent phospho-transfer mechanism via a phospho-enzyme intermediate. Crystal structures of bi-domain iPGM from Staphylococcus aureus, together with substrate-bound forms, have revealed a new conformation of the enzyme, representing an intermediate state of domain movement. The substrate-binding site and the catalytic site are present in two distinct domains in the intermediate form. X-ray crystallography complemented by simulated dynamics has enabled delineation of the complete catalytic cycle, which includes binding of the substrate, followed by its positioning into the catalytic site, phospho-transfer and finally product release. The present work describes a novel mechanism of domain movement controlled by a hydrophobic patch that is exposed on domain closure and acts like a spring to keep the protein in open conformation. Domain closing occurs after substrate binding, and is essential for phospho-transfer, whereas the open conformation is a prerequisite for efficient substrate binding and product dissociation. A new model of catalysis has been proposed by correlating the hinge-bending motion with the phospho-transfer mechanism.

Original publication

DOI

10.1111/febs.13205

Type

Journal article

Journal

FEBS J

Publication Date

03/2015

Volume

282

Pages

1097 - 1110

Keywords

Staphylococcus aureus, X-ray diffraction, catalytic mechanism, cofactor-independent phosphoglycerate mutase, hinge-bending motion, Catalysis, Catalytic Domain, Computer Simulation, Crystallography, X-Ray, Ligands, Manganese, Models, Molecular, Motion, Phosphoglycerate Mutase, Protein Binding, Staphylococcus aureus, Substrate Specificity, Thermodynamics, X-Ray Diffraction