4DK1

Crystal Structure of MacA-MexA chimeric protein, containing the Pseudomonas aeruginosa MexA alpha-hairpin domain.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.368 
  • R-Value Work: 0.314 
  • R-Value Observed: 0.317 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Assembly and channel opening of outer membrane protein in tripartite drug efflux pumps of Gram-negative bacteria.

Xu, Y.Moeller, A.Jun, S.Y.Le, M.Yoon, B.Y.Kim, J.S.Lee, K.Ha, N.C.

(2012) J Biol Chem 287: 11740-11750

  • DOI: https://doi.org/10.1074/jbc.M111.329375
  • Primary Citation of Related Structures:  
    4DK0, 4DK1

  • PubMed Abstract: 

    Gram-negative bacteria are capable of expelling diverse xenobiotic substances from within the cell by use of three-component efflux pumps in which the energy-activated inner membrane transporter is connected to the outer membrane channel protein via the membrane fusion protein. In this work, we describe the crystal structure of the membrane fusion protein MexA from the Pseudomonas aeruginosa MexAB-OprM pump in the hexameric ring arrangement. Electron microscopy study on the chimeric complex of MexA and the outer membrane protein OprM reveals that MexA makes a tip-to-tip interaction with OprM, which suggests a docking model for MexA and OprM. This docking model agrees well with genetic results and depicts detailed interactions. Opening of the OprM channel is accompanied by the simultaneous exposure of a protein structure resembling a six-bladed cogwheel, which intermeshes with the complementary cogwheel structure in the MexA hexamer. Taken together, we suggest an assembly and channel opening model for the MexAB-OprM pump. This study provides a better understanding of multidrug resistance in Gram-negative bacteria.


  • Organizational Affiliation

    Department of Manufacturing Pharmacy, College of Pharmacy and Research Institute for Drug Development, Pusan National University, Busan 609-735, Korea.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Putative MacA, Multidrug resistance protein mexA
A, B, C, D
341Aggregatibacter actinomycetemcomitansPseudomonas aeruginosa PAO1Mutation(s): 0 
Gene Names: mexAPA0425
UniProt
Find proteins for P52477 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1))
Explore P52477 
Go to UniProtKB:  P52477
Find proteins for Q2EHL9 (Aggregatibacter actinomycetemcomitans)
Explore Q2EHL9 
Go to UniProtKB:  Q2EHL9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupsQ2EHL9P52477
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, D
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.50 Å
  • R-Value Free: 0.368 
  • R-Value Work: 0.314 
  • R-Value Observed: 0.317 
  • Space Group: P 3 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 151.708α = 90
b = 151.708β = 90
c = 216.953γ = 120
Software Package:
Software NamePurpose
HKL-2000data collection
MOLREPphasing
PHENIXrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2012-03-07
    Type: Initial release
  • Version 1.1: 2015-12-09
    Changes: Database references
  • Version 1.2: 2017-08-23
    Changes: Advisory, Refinement description, Source and taxonomy