1NP6

Crystal structure of Escherichia coli MobB


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.285 
  • R-Value Work: 0.215 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Insight into the role of Escherichia coli MobB in Molybdenum cofactor biosynthesis based on the high resolution crystal structure

McLuskey, K.Harrison, J.A.Schuttelkopf, A.W.Boxer, D.H.Hunter, W.N.

(2003) J.Biol.Chem. 278: 23706-23713

  • DOI: 10.1074/jbc.M301485200

  • PubMed Abstract: 
  • Two proteins, which are co-transcribed in Escherichia coli (MobA and MobB), are involved in the attachment of a nucleotide moiety to the molybdenum cofactor to form active molybdopterin guanine dinucleotide. Although not essential for this process, t ...

    Two proteins, which are co-transcribed in Escherichia coli (MobA and MobB), are involved in the attachment of a nucleotide moiety to the molybdenum cofactor to form active molybdopterin guanine dinucleotide. Although not essential for this process, the dimeric MobB increases the activation of molybdoenzymes, incorporating this cofactor by a mechanism that is not understood. The structure of MobB has been elucidated in two crystal forms, one of which has provided a model at 1.9-A resolution with Rwork and Rfree values of 21.5 and 28.7%, respectively. The MobB subunit displays an alpha/beta-fold arranged into a major and minor domain, the latter of which is inserted between the major and minor domains of the partner subunit, creating an elongated dimer constructed around a 16-stranded beta-sheet. Structural homologues have been identified, and they include a number of nucleotide-binding proteins. Comparisons indicate that although the phosphate-binding regions are highly conserved, MobB lacks the elements of structure required to interact with and efficiently bind a nucleotide base. In the present structure, a sulfate is bound to the Walker A phosphate-binding motif of MobB. The possibility that MobB forms a complex with the nucleotide-binding MobA, the protein with which it is co-transcribed, is explored, and modeling suggests that such a MobA:MobB complex is feasible. This hypothesis is supported by recent biochemical evidence indicating that MobB interacts with several proteins involved in various stages of molybdenum cofactor biosynthesis including MobA. We propose therefore that MobB is an adapter protein that acts in concert with MobA to achieve the efficient biosynthesis and utilization of molybdopterin guanine dinucleotide.


    Organizational Affiliation

    Division of Biological Chemistry and Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Molybdopterin-guanine dinucleotide biosynthesis protein B
A, B
174Escherichia coli (strain K12)Gene Names: mobB (yihC)
Find proteins for P32125 (Escherichia coli (strain K12))
Go to UniProtKB:  P32125
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.285 
  • R-Value Work: 0.215 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 52.400α = 90.00
b = 64.791β = 97.68
c = 54.241γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
HKL-2000data reduction
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-04-29
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2018-01-31
    Type: Experimental preparation