3FPP

Crystal structure of E.coli MacA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.99 Å
  • R-Value Free: 0.349 
  • R-Value Work: 0.283 
  • R-Value Observed: 0.283 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Crystal structure of the periplasmic component of a tripartite macrolide-specific efflux pump

Yum, S.Xu, Y.Piao, S.Sim, S.-H.Kim, H.-M.Jo, W.-S.Kim, K.-J.Kweon, H.-S.Jeong, M.-H.Jeon, H.Lee, K.Ha, N.-C.

(2009) J Mol Biol 387: 1286-1297

  • DOI: 10.1016/j.jmb.2009.02.048
  • Primary Citation of Related Structures:  
    3FPP

  • PubMed Abstract: 
  • In Gram-negative bacteria, type I protein secretion systems and tripartite drug efflux pumps have a periplasmic membrane fusion protein (MFP) as an essential component. MFPs bridge the outer membrane factor and an inner membrane transporter, although ...

    In Gram-negative bacteria, type I protein secretion systems and tripartite drug efflux pumps have a periplasmic membrane fusion protein (MFP) as an essential component. MFPs bridge the outer membrane factor and an inner membrane transporter, although the oligomeric state of MFPs remains unclear. The most characterized MFP AcrA connects the outer membrane factor TolC and the resistance-nodulation-division-type efflux transporter AcrB, which is a major multidrug efflux pump in Escherichia coli. MacA is the periplasmic MFP in the MacAB-TolC pump, where MacB was characterized as a macrolide-specific ATP-binding-cassette-type efflux transporter. Here, we report the crystal structure of E. coli MacA and the experimentally phased map of Actinobacillus actinomycetemcomitans MacA, which reveal a domain orientation of MacA different from that of AcrA. Notably, a hexameric assembly of MacA was found in both crystals, exhibiting a funnel-like structure with a central channel and a conical mouth. The hexameric MacA assembly was further confirmed by electron microscopy and functional studies in vitro and in vivo. The hexameric structure of MacA provides insight into the oligomeric state in the functional complex of the drug efflux pump and type I secretion system.


    Organizational Affiliation

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



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Macrolide-specific efflux protein macAAB341Escherichia coliMutation(s): 0 
Gene Names: macA
Find proteins for P75830 (Escherichia coli (strain K12))
Explore P75830 
Go to UniProtKB:  P75830
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.99 Å
  • R-Value Free: 0.349 
  • R-Value Work: 0.283 
  • R-Value Observed: 0.283 
  • Space Group: P 3 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 128.517α = 90
b = 128.517β = 90
c = 110.311γ = 120
Software Package:
Software NamePurpose
HKL-2000data collection
MOLREPphasing
CNSrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-04-28
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance