3BB4

Crystal structure of Toc33 from Arabidopsis thaliana in complex with Mg2+ and GMPPNP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.277 
  • R-Value Work: 0.218 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The GTPase cycle of the chloroplast import receptors Toc33/Toc34: implications from monomeric and dimeric structures.

Koenig, P.Oreb, M.Hofle, A.Kaltofen, S.Rippe, K.Sinning, I.Schleiff, E.Tews, I.

(2008) Structure 16: 585-596

  • DOI: 10.1016/j.str.2008.01.008
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Transport of precursor proteins across chloroplast membranes involves the GTPases Toc33/34 and Toc159 at the outer chloroplast envelope. The small GTPase Toc33/34 can homodimerize, but the regulation of this interaction has remained elusive. We show ...

    Transport of precursor proteins across chloroplast membranes involves the GTPases Toc33/34 and Toc159 at the outer chloroplast envelope. The small GTPase Toc33/34 can homodimerize, but the regulation of this interaction has remained elusive. We show that dimerization is independent of nucleotide loading state, based on crystal structures of dimeric Pisum sativum Toc34 and monomeric Arabidopsis thaliana Toc33. An arginine residue is--in the dimer--positioned to resemble a GAP arginine finger. However, GTPase activation by dimerization is sparse and active site features do not explain catalysis, suggesting that the homodimer requires an additional factor as coGAP. Access to the catalytic center and an unusual switch I movement in the dimeric structure support this finding. Potential binding sites for interactions within the Toc translocon or with precursor proteins can be derived from the structures.


    Organizational Affiliation

    Heidelberg University Biochemistry Center, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
T7I23.11 protein
A
262Arabidopsis thalianaMutation(s): 1 
Gene Names: TOC33 (PPI1)
EC: 3.6.5.-
Find proteins for O23680 (Arabidopsis thaliana)
Go to UniProtKB:  O23680
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
GNP
Query on GNP

Download SDF File 
Download CCD File 
A
PHOSPHOAMINOPHOSPHONIC ACID-GUANYLATE ESTER
C10 H17 N6 O13 P3
UQABYHGXWYXDTK-UUOKFMHZSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.277 
  • R-Value Work: 0.218 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 121.567α = 90.00
b = 121.567β = 90.00
c = 42.879γ = 90.00
Software Package:
Software NamePurpose
DNAdata collection
REFMACrefinement
SCALEPACKdata scaling
HKL-2000data reduction
MOLREPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-04-01
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance
  • Version 1.2: 2014-11-12
    Type: Structure summary