Structure of a Transient Intermediate for GTP Hydrolysis by Ras
نویسندگان
چکیده
منابع مشابه
Kinetic isotope effects in Ras-catalyzed GTP hydrolysis: evidence for a loose transition state.
A remote labeling method has been developed to determine (18)O kinetic isotope effects (KIEs) in Ras-catalyzed GTP hydrolysis. Substrate mixtures consist of (13)C-depleted GTP and [(18)O,(13)C]GTP that contains (18)O at phosphoryl positions of mechanistic interest and (13)C at all carbon positions of the guanosine moiety. Isotope ratios of the nonvolatile substrates and products are measured by...
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Despite the biological and medical importance of signal transduction via Ras proteins and despite considerable kinetic and structural studies of wild-type and mutant Ras proteins, the mechanism of Ras-catalyzed GTP hydrolysis remains controversial. We take a different approach to this problem: the uncatalyzed hydrolysis of GTP is analyzed, and the understanding derived is applied to the Ras-cat...
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ژورنال
عنوان ژورنال: Structure
سال: 2006
ISSN: 0969-2126
DOI: 10.1016/j.str.2005.12.010