2IZ6

Structure of the Chlamydomonas rheinhardtii Moco Carrier Protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.184 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Function and Structure of the Molybdenum Cofactor Carrier Protein from Chlamydomonas Reinhardtii.

Fischer, K.Llamas, A.Tejada-Jimenez, M.Schrader, N.Kuper, J.Ataya, F.S.Galvan, A.Mendel, R.R.Fernandez, E.Schwarz, G.

(2006) J.Biol.Chem. 281: 30186

  • DOI: 10.1074/jbc.M603919200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The molybdenum cofactor (Moco) forms the catalytic site in all eukaryotic molybdenum enzymes and is synthesized by a multistep biosynthetic pathway. The mechanism of transfer, storage, and insertion of Moco into the appropriate apo-enzyme is poorly u ...

    The molybdenum cofactor (Moco) forms the catalytic site in all eukaryotic molybdenum enzymes and is synthesized by a multistep biosynthetic pathway. The mechanism of transfer, storage, and insertion of Moco into the appropriate apo-enzyme is poorly understood. In Chlamydomonas reinhardtii, a Moco carrier protein (MCP) has been identified and characterized recently. Here we show biochemical evidence that MCP binds Moco as well as the tungstate-substituted form of the cofactor (Wco) with high affinity, whereas molybdopterin, the ultimate cofactor precursor, is not bound. This binding selectivity points to a specific metal-mediated interaction with MCP, which protects Moco and Wco from oxidation with t((1/2)) of 24 and 96 h, respectively. UV-visible spectroscopy showed defined absorption bands at 393, 470, and 570 nm pointing to ene-diothiolate and protein side-chain charge transfer bonds with molybdenum. We have determined the crystal structure of MCP at 1.6 Angstrom resolution using seleno-methionated and native protein. The monomer constitutes a Rossmann fold with two homodimers forming a symmetrical tetramer in solution. Based on conserved surface residues, charge distribution, shape, in silico docking studies, structural comparisons, and identification of an anionbinding site, a prominent surface depression was proposed as a Moco-binding site, which was confirmed by structure-guided mutagenesis coupled to substrate binding studies.


    Organizational Affiliation

    Institute of Plant Biology, Technical University Braunschweig, 38106 Braunschweig, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MOLYBDENUM COFACTOR CARRIER PROTEIN
A, B
176Chlamydomonas reinhardtiiMutation(s): 0 
Gene Names: MCP (MCP1)
Find proteins for Q8RV61 (Chlamydomonas reinhardtii)
Go to UniProtKB:  Q8RV61
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.184 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 68.079α = 90.00
b = 126.009β = 90.00
c = 75.680γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-07-26
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance