4NHR

Crystal structure of the outer membrane lipopolysaccharide transport protein LptE (RlpB)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.34 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.227 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

LptE binds to and alters the physical state of LPS to catalyze its assembly at the cell surface.

Malojcic, G.Andres, D.Grabowicz, M.George, A.H.Ruiz, N.Silhavy, T.J.Kahne, D.

(2014) Proc Natl Acad Sci U S A 111: 9467-9472

  • DOI: 10.1073/pnas.1402746111
  • Primary Citation of Related Structures:  
    4NHR

  • PubMed Abstract: 
  • The assembly of lipopolysaccharide (LPS) on the surface of Gram-negative bacterial cells is essential for their viability and is achieved by the seven-protein LPS transport (Lpt) pathway. The outer membrane (OM) lipoprotein LptE and the β-barrel membrane protein LptD form a complex that assembles LPS into the outer leaflet of the OM ...

    The assembly of lipopolysaccharide (LPS) on the surface of Gram-negative bacterial cells is essential for their viability and is achieved by the seven-protein LPS transport (Lpt) pathway. The outer membrane (OM) lipoprotein LptE and the β-barrel membrane protein LptD form a complex that assembles LPS into the outer leaflet of the OM. We report a crystal structure of the Escherichia coli OM lipoprotein LptE at 2.34 Å. The structure reveals homology to eukaryotic LPS-binding proteins and allowed for the prediction of an LPS-binding site, which was confirmed by genetic and biophysical experiments. Specific point mutations at this site lead to defects in OM biogenesis. We show that wild-type LptE disrupts LPS-LPS interactions in vitro and that these mutations decrease the ability of LptE to disaggregate LPS. Transmission electron microscopic imaging shows that LptE can disrupt LPS aggregates even at substoichiometric concentrations. We propose a model in which LptE functions as an LPS transfer protein in the OM translocon by disaggregating LPS during transport to allow for its insertion into the OM.


    Organizational Affiliation

    Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138;Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, MA 02115 tsilhavy@princeton.edu kahne@chemistry.harvard.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
LPS-assembly lipoprotein LptEA168Escherichia coli K-12Mutation(s): 0 
Gene Names: b0641JW0636lptErlpB
Membrane Entity: Yes 
UniProt
Find proteins for P0ADC1 (Escherichia coli (strain K12))
Explore P0ADC1 
Go to UniProtKB:  P0ADC1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0ADC1
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PEG
Query on PEG

Download Ideal Coordinates CCD File 
B [auth A]DI(HYDROXYETHYL)ETHER
C4 H10 O3
MTHSVFCYNBDYFN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.34 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.227 
  • Space Group: P 65 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 87.67α = 90
b = 87.67β = 90
c = 104.36γ = 120
Software Package:
Software NamePurpose
ADSCdata collection
SHARPphasing
PHENIXrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-07-16
    Type: Initial release