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1p2s
From Proteopedia
H-Ras 166 in 50% 2,2,2 triflouroethanol
Overview
Room temperature crystal structures of crosslinked H-Ras bound to GMPPNP were solved in 50% 2,2,2-trifluoroethanol, 60% 1,6-hexanediol, and 50% isopropanol. The disordered switch II region of Ras is ordered in the presence of 2,2,2-trifluoroethanol or 1,6-hexanediol. The overall backbone conformation of switch II in these organic solvents is the same as in the Ras-GMPPNP complexes with RalGDS, PI(3) kinase, and RasGAP, indicating a biologically relevant form. Key polar interactions that stabilize the ordered switch are enhanced in the presence of hydrophobic cosolvents. These results suggest that hydrophobic solvents can be used in general to order short biologically relevant segments of disordered regions in protein crystals by favoring H-bonding interactions between atoms that are highly solvated and mobile in aqueous solution.
About this Structure
1P2S is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Organic solvents order the dynamic switch II in Ras crystals., Buhrman G, de Serrano V, Mattos C, Structure. 2003 Jul;11(7):747-51. PMID:12842038 Page seeded by OCA on Sat May 3 04:36:39 2008
