Related Experiment Videos
An atomic model for protein-protein phosphoryl group transfer
1Center for Advanced Research in Biotechnology, Maryland Biotechnology Institute, University of Maryland, Rockville 20850.
The Journal of Biological Chemistry
|December 5, 1992
Summary
High-resolution structures reveal how Bacillus subtilis proteins HPr and IIA(Glc) interact during phosphoryl transfer. A switch between salt bridges involving HPr
Area of Science:
- Biochemistry
- Structural Biology
- Molecular Biology
Background:
- The phosphoenolpyruvate:sugar phosphotransferase system facilitates sugar uptake and metabolism.
- Understanding protein-protein interactions is crucial for elucidating enzyme mechanisms.
Purpose of the Study:
- To model the transient complex between HPr and IIA(Glc) from Bacillus subtilis.
- To investigate the structural basis of phosphoryl group transfer between these proteins.
Main Methods:
- High-resolution crystal structure determination of interacting proteins.
- Computational modeling of the transient binary complex.
Main Results:
- The crystal structures reveal complementary interacting surfaces requiring no major conformational changes.
- A negatively charged phosphoryl group is buried at the interface, indicating the importance of electrostatic interactions.
- A proposed mechanism involves a switch between intramolecular and intermolecular salt bridges involving HPr's Arg-17.
Conclusions:
- The study provides a structural basis for the HPr-IIA(Glc) interaction and phosphoryl transfer mechanism.
- Alternating salt bridge formation may be a conserved mechanism in other protein phosphotransfer reactions.