1P2U

H-Ras in 50% isopropanol

• PDB DOI: https://doi.org/10.2210/pdb1P2U/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2003-04-16 Released: 2003-08-05 
• Deposition Author(s): Buhrman, G.K., de Serrano, V., Mattos, C.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.248 
• R-Value Work: 0.212 
• R-Value Observed: 0.212 

Starting Model: experimental

Literature

Organic solvents order the dynamic switch II in Ras crystals

Buhrman, G.K., de Serrano, V., Mattos, C.

(2003) Structure 11: 747-751

• PubMed: 12842038 
• DOI: https://doi.org/10.1016/s0969-2126(03)00128-x
• Primary Citation of Related Structures:  
  1P2S, 1P2T, 1P2U, 1P2V


• PubMed Abstract: 
  

  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.

---

Organizational Affiliation: 

Department of Molecular and Structural Biochemistry, North Carolina State University, 128 Polk Hall, Raleigh, NC 27695, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 19.6 kDa 
• Atom Count: 1,426 
• Modelled Residue Count: 162 
• Deposited Residue Count: 166 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Transforming protein p21/H-RAS-1	A	166	Homo sapiens	Mutation(s): 0  Gene Names: HRAS OR HRAS1 EC: 3.6.5.2
UniProt & NIH Common Fund Data Resources
Find proteins for P01112 (Homo sapiens) Explore P01112  Go to UniProtKB:  P01112
PHAROS:  P01112 GTEx:  ENSG00000174775

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GNP	C [auth A]	PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER C10 H17 N6 O13 P3 UQABYHGXWYXDTK-UUOKFMHZSA-N
IPA	D [auth A], E [auth A], F [auth A]	ISOPROPYL ALCOHOL C3 H8 O KFZMGEQAYNKOFK-UHFFFAOYSA-N
MG	B [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.248 
• R-Value Work: 0.212 
• R-Value Observed: 0.212 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 40.077	α = 90
b = 40.077	β = 90
c = 161.856	γ = 120

Software Package:

Software Name	Purpose
CNS	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2003-08-05 
Deposition Author(s): Buhrman, G.K., de Serrano, V., Mattos, C.

Revision History  

• Version 1.0: 2003-08-05
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2023-08-16
  Changes: Data collection, Database references, Derived calculations, Refinement description