3PRW

Crystal structure of the lipoprotein BamB


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.183 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Augmenting beta-augmentation: structural basis of how BamB binds BamA and may support folding of outer membrane proteins.

Heuck, A.Schleiffer, A.Clausen, T.

(2011) J.Mol.Biol. 406: 659-666

  • DOI: 10.1016/j.jmb.2011.01.002

  • PubMed Abstract: 
  • β-Barrel proteins are frequently found in the outer membrane of mitochondria, chloroplasts and Gram-negative bacteria. In Escherichia coli, these proteins are inserted in the outer membrane by the Bam (β-barrel assembly machinery) complex, a multipro ...

    β-Barrel proteins are frequently found in the outer membrane of mitochondria, chloroplasts and Gram-negative bacteria. In Escherichia coli, these proteins are inserted in the outer membrane by the Bam (β-barrel assembly machinery) complex, a multiprotein machinery formed by the β-barrel protein BamA and the four peripheral membrane proteins BamB, BamC, BamD and BamE. The periplasmic part of BamA binds prefolded β-barrel proteins by a β-augmentation mechanism, thereby stabilizing the precursors prior to their membrane insertion. However, the role of the associated proteins within the Bam complex remains unknown. Here, we describe the crystal structure of BamB, a nonessential component of the Bam complex. The structure shows a typical eight-bladed β-propeller fold. Two sequence stretches of BamB were previously identified to be important for interaction with BamA. In our structure, both motifs are located in close proximity to each other and contribute to a conserved region forming a narrow groove on the top of the propeller. Moreover, crystal contacts reveal two interaction modes of how BamB might bind unfolded β-barrel proteins. In the crystal lattice, BamB binds to exposed β-strands by β-augmentation, whereas peptide stretches rich in aromatic residues can be accommodated in hydrophobic pockets located at the bottom of the propeller. Thus, BamB could simultaneously bind to BamA and prefolded β-barrel proteins, thereby enhancing the folding and membrane insertion capability of the Bam complex.


    Organizational Affiliation

    Research Institute of Molecular Pathology, Dr. Bohrgasse 7, A-1030 Vienna, Austria.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Lipoprotein yfgL
A
377Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: bamB (yfgL)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Omp85-TpsB Outer Membrane Transporter Superfamily
Protein: 
BamB component of the Bam β-barrel assembly machine
Find proteins for P77774 (Escherichia coli (strain K12))
Go to UniProtKB:  P77774
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.204 
  • R-Value Work: 0.183 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 50.221α = 90.00
b = 120.967β = 90.00
c = 134.117γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
SHARPphasing
SOLOMONphasing
PHENIXrefinement
PDB_EXTRACTdata extraction
SCALAdata scaling
RemDAqdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2010-11-30 
  • Released Date: 2011-01-19 
  • Deposition Author(s): Heuck, A., Clausen, T.

Revision History 

  • Version 1.0: 2011-01-19
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2015-02-25
    Type: Database references