1JAI

H-RAS P21 PROTEIN MUTANT G12P, COMPLEXED WITH GUANOSINE-5'-[BETA,GAMMA-METHYLENE] TRIPHOSPHATE AND MANGANESE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

The role of the metal ion in the p21ras catalysed GTP-hydrolysis: Mn2+ versus Mg2+.

Schweins, T.Scheffzek, K.Assheuer, R.Wittinghofer, A.

(1997) J Mol Biol 266: 847-856

  • DOI: 10.1006/jmbi.1996.0814
  • Primary Citation of Related Structures:  
    1JAI, 1JAH

  • PubMed Abstract: 
  • GTP and ATP hydrolysing proteins have an absolute requirement for a divalent cation, which is usually Mg2+, as a cofactor in the enzymatic reaction. Other phosphoryl transfer enzymes employ more than one divalent ion for the enzymatic reaction. It is shown here for p21ras, a well studied example of GTP hydrolysing proteins, that the GTP-hydrolysis rate is significantly faster if Mg2+ is replaced by Mn2+, both in the presence or absence of its GTPase-activating protein Ras-GAP ...

    GTP and ATP hydrolysing proteins have an absolute requirement for a divalent cation, which is usually Mg2+, as a cofactor in the enzymatic reaction. Other phosphoryl transfer enzymes employ more than one divalent ion for the enzymatic reaction. It is shown here for p21ras, a well studied example of GTP hydrolysing proteins, that the GTP-hydrolysis rate is significantly faster if Mg2+ is replaced by Mn2+, both in the presence or absence of its GTPase-activating protein Ras-GAP. This effect is not due to a different stoichiometry of metal ion binding, since one metal ion is sufficient for full enzymatic activity. To determine the role of the metal ion, the crystal structure of p21(G12P). GppCp complexed with Mn2+ was determined and shown to be very similar to the corresponding p21(G12P). GppCp.Mg2+ structure. Especially the coordination sphere around the metal ions is very similar, and no second metal ion binding site could be detected, consistent with the assumption that one metal ion is sufficient for GTP hydrolysis. In order to explain the biochemical differences, we analysed the GTPase reaction mechanism with a linear free energy relationships approach. The result suggests that the reaction mechanism is not changed with Mn2+ but that the transition metal ion Mn2+ shifts the pKa of the gamma-phosphate by almost half a unit and increases the reaction rate due to an increase in the basicity of GTP acting as the general base. This suggests that the intrinsic GTPase reaction could be an attractive target for anti-cancer drug design. By using Rap1A and Ran, we show that the acceleration of the GTPase by Mn2+ appears to be a general phenomenon of GTP-binding proteins.


    Related Citations: 
    • Refined Crystal Structure of the Triphosphate Conformation of H-Ras P21 at 1.35 A Resolution: Implications for the Mechanism of GTP Hydrolysis
      Pai, E.F., Krengel, U., Petsko, G.A., Goody, R.S., Kabsch, W., Wittinghofer, A.
      (1990) EMBO J 9: 2351
    • Biological Properties of Human C-Ha-Ras1 Genes Mutated at Codon 12
      Seeburg, P.H., Colby, W.W., Capon, D.J., Goeddel, D.V., Levinson, A.D.
      (1984) Nature 312: 71

    Organizational Affiliation

    Max-Planck-Institut für molekulare Physiologie, Dortmund, Germany.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
C-HA-RASA166Homo sapiensMutation(s): 1 
Gene Names: H-RAS-1HRASHRAS1
EC: 3.6.5.2
Find proteins for P01112 (Homo sapiens)
Explore P01112 
Go to UniProtKB:  P01112
NIH Common Fund Data Resources
PHAROS:  P01112
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GCP
Query on GCP

Download Ideal Coordinates CCD File 
C [auth A]PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER
C11 H18 N5 O13 P3
PHBDHXOBFUBCJD-KQYNXXCUSA-N
 Ligand Interaction
MN
Query on MN

Download Ideal Coordinates CCD File 
B [auth A]MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.80 Å
  • R-Value Free: 0.290 
  • R-Value Work: 0.200 
  • R-Value Observed: 0.200 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 40α = 90
b = 40β = 90
c = 160.4γ = 120
Software Package:
Software NamePurpose
X-PLORmodel building
X-PLORrefinement
XDSdata reduction
XSCALEdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1997-07-23
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance