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Updated: Sep 29, 2026

Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
GTPase-activating proteins: helping hands to complement an active site
K Scheffzek1, M R Ahmadian, A Wittinghofer
1Max-Planck-Institut für Molekulare Physiologie, Dortmund, Germany.
Abstract:
Stimulation of the intrinsic GTPase activity of GTP-binding proteins by GTPase-activating proteins (GAPs) is a basic principle of GTP-binding-protein downregulation. Recently, the molecular mechanism behind this reaction has been elucidated by studies on Ras and Rho, and their respective GAPs. The basic features involve stabilizing the existing catalytic machinery and supplementing it by an external arginine residue. This represents a novel mechanism for enzyme active-site formation.
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