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 

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.USA 111: 9467-9472

  • DOI: 10.1073/pnas.1402746111

  • 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 memb ...

    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;




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
LPS-assembly lipoprotein LptE
A
168Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: lptE (rlpB)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: BETA-BARREL
Sub Group: 
Lipopolysaccharide (LPS) Transport Proteins
Protein: 
LptE lipopolysaccharide transport protein
Find proteins for P0ADC1 (Escherichia coli (strain K12))
Go to UniProtKB:  P0ADC1
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PEG
Query on PEG

Download SDF File 
Download CCD File 
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 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 87.670α = 90.00
b = 87.670β = 90.00
c = 104.360γ = 120.00
Software Package:
Software NamePurpose
SCALAdata scaling
MOSFLMdata reduction
PHENIXrefinement
ADSCdata collection
SHARPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

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