1RFL

NMR data driven structural model of G-domain of MnmE protein


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural insights into the GTPase domain of Escherichia coli MnmE protein.

Monleon, D.Martinez-Vicente, M.Esteve, V.Yim, L.Prado, S.Armengod, M.E.Celda, B.

(2007) Proteins 66: 726-739

  • DOI: 10.1002/prot.21186

  • PubMed Abstract: 
  • The Escherichia coli MnmE protein is a 50-kDa multidomain GTPase involved in tRNA modification. Its homologues in eukaryotes are crucial for mitochondrial respiration and, thus, it is thought that the human protein might be involved in mitochondrial ...

    The Escherichia coli MnmE protein is a 50-kDa multidomain GTPase involved in tRNA modification. Its homologues in eukaryotes are crucial for mitochondrial respiration and, thus, it is thought that the human protein might be involved in mitochondrial diseases. Unlike Ras, MnmE shows a high intrinsic GTPase activity and requires effective GTP hydrolysis, and not simply GTP binding, to be functionally active. The isolated MnmE G-domain (165 residues) conserves the GTPase activity of the entire protein, suggesting that it contains the catalytic residues for GTP hydrolysis. To explore the GTP hydrolysis mechanism of MnmE, we analyzed the effect of low pH on binding and hydrolysis of GTP, as well as on the formation of a MnmE transition state mimic. GTP hydrolysis by MnmE, but not GTP binding or formation of a complex with mant-GDP and aluminium fluoride, is impaired at acidic pH, suggesting that the chemistry of the transition state mimic is different to that of the true transition state, and that some residue(s), critical for GTP hydrolysis, is severely affected by low pH. We use a nuclear magnetic resonance (NMR)-based approach to get insights into the MnmE structure and properties. The combined use of NMR restraints and homology structural information allowed the determination of the MnmE G-domain structure in its free form. Chemical shift structure-based prediction provided a good basis for structure refinement and validation. Our data support that MnmE, unlike other GTPases, does not use an arginine finger to drive catalysis, although Arg252 may play a role in stabilization of the transition state.


    Organizational Affiliation

    Department of Physical Chemistry, University of Valencia, C/Dr. Moliner, 50, Burjassot 46100 Valencia, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Probable tRNA modification GTPase trmE
A
172Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: mnmE (thdF, trmE)
EC: 3.6.-.-
Find proteins for P25522 (Escherichia coli (strain K12))
Go to UniProtKB:  P25522
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1RFL Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-12-02
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance