Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2011 Apr 22;286(16):14040-8. doi: 10.1074/jbc.M110.206813. Epub 2011 Feb 24.

A spring-loaded release mechanism regulates domain movement and catalysis in phosphoglycerate kinase.

Author information

  • 1Structural Biology Group, European Synchrotron Radiation Facility, 6 rue Jules Horowitz, F-38043 Grenoble, France.

Abstract

Phosphoglycerate kinase (PGK) is the enzyme responsible for the first ATP-generating step of glycolysis and has been implicated extensively in oncogenesis and its development. Solution small angle x-ray scattering (SAXS) data, in combination with crystal structures of the enzyme in complex with substrate and product analogues, reveal a new conformation for the resting state of the enzyme and demonstrate the role of substrate binding in the preparation of the enzyme for domain closure. Comparison of the x-ray scattering curves of the enzyme in different states with crystal structures has allowed the complete reaction cycle to be resolved both structurally and temporally. The enzyme appears to spend most of its time in a fully open conformation with short periods of closure and catalysis, thereby allowing the rapid diffusion of substrates and products in and out of the binding sites. Analysis of the open apoenzyme structure, defined through deformable elastic network refinement against the SAXS data, suggests that interactions in a mostly buried hydrophobic region may favor the open conformation. This patch is exposed on domain closure, making the open conformation more thermodynamically stable. Ionic interactions act to maintain the closed conformation to allow catalysis. The short time PGK spends in the closed conformation and its strong tendency to rest in an open conformation imply a spring-loaded release mechanism to regulate domain movement, catalysis, and efficient product release.

PMID:
21349853
[PubMed - indexed for MEDLINE]
PMCID:
PMC3077604
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk