6O30

Lipid A transporter MsbA from Salmonella typhimurium


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.47 Å
  • R-Value Free: 0.340 
  • R-Value Work: 0.307 
  • R-Value Observed: 0.308 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structural Insights into the Lipid A Transport Pathway in MsbA.

Padayatti, P.S.Lee, S.C.Stanfield, R.L.Wen, P.C.Tajkhorshid, E.Wilson, I.A.Zhang, Q.

(2019) Structure 27: 1114-1123.e3

  • DOI: https://doi.org/10.1016/j.str.2019.04.007
  • Primary Citation of Related Structures:  
    6BL6, 6O30

  • PubMed Abstract: 

    MsbA is an essential ATP-binding cassette transporter in Gram-negative bacteria that transports lipid A and lipopolysaccharide from the cytoplasmic leaflet to the periplasmic leaflet of the inner membrane. Here we report the X-ray structure of MsbA from Salmonella typhimurium at 2.8-Å resolution in an inward-facing conformation after cocrystallization with lipid A and using a stabilizing facial amphiphile. The structure displays a large amplitude opening in the transmembrane portal, which is likely required for lipid A to pass from its site of synthesis into the protein-enclosed transport pathway. Putative lipid A density is observed further inside the transmembrane cavity, consistent with a trap and flip model. Additional electron density attributed to lipid A is observed near an outer surface cleft at the periplasmic ends of the transmembrane helices. These findings provide new structural insights into the lipid A transport pathway through comparative analysis with existing MsbA structures.


  • Organizational Affiliation

    Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Lipid A export ATP-binding/permease protein MsbA
A, B
576Salmonella enterica subsp. enterica serovar TyphimuriumMutation(s): 0 
Gene Names: msbADD95_15660EIL76_15590
EC: 7.5.2.6
Membrane Entity: Yes 
UniProt
Find proteins for P63359 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720))
Explore P63359 
Go to UniProtKB:  P63359
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP63359
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 4.47 Å
  • R-Value Free: 0.340 
  • R-Value Work: 0.307 
  • R-Value Observed: 0.308 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 82.257α = 90
b = 153.2β = 90
c = 232.483γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data reduction
SCALEPACKdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesR01 GM09853
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesR01 GM118594

Revision History  (Full details and data files)

  • Version 1.0: 2019-06-12
    Type: Initial release
  • Version 1.1: 2019-07-17
    Changes: Data collection, Database references
  • Version 1.2: 2020-01-01
    Changes: Author supporting evidence
  • Version 1.3: 2020-03-04
    Changes: Data collection
  • Version 1.4: 2023-10-11
    Changes: Data collection, Database references, Refinement description