Your browser version may not work well with NCBI's Web applications. More information here...
1: Proc Natl Acad Sci U S A. 2006 Sep 19;103(38):13911-6. Epub 2006 Sep 12.
Related Articles, Links
Click here to read Click here to read Click here to read
A phosphoryl transfer intermediate in the GTPase reaction of Ras in complex with its GTPase-activating protein.

Kötting C, Blessenohl M, Suveyzdis Y, Goody RS, Wittinghofer A, Gerwert K.

Lehrstuhl für Biophysik and Institut für Physiologische Chemie, Ruhr-Universität Bochum, D-44780 Bochum, Germany.

The hydrolysis of nucleoside triphosphates by enzymes is used as a regulation mechanism in key biological processes. Here, the GTP hydrolysis of the protein complex of Ras with its GTPase-activating protein is monitored at atomic resolution in a noncrystalline state by time-resolved FTIR spectroscopy. At 900 ms, after the attack of water at the gamma-phosphate, there appears a H2PO4- intermediate that is shown to be hydrogen-bonded in an eclipsed conformation to the beta-phosphate of GDP. The H2PO4- intermediate is in a position where it can either reform GTP or be released from the protein in 7 s in the rate-limiting step of the GTPase reaction. We propose that such an intermediate also occurs in other GTPases and ATPases.

Publication Types:
PMID: 16968776 [PubMed - indexed for MEDLINE]

PMCID: PMC1599887