2CFQ

Sugar Free Lactose Permease at neutral pH


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.95 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.262 
  • R-Value Observed: 0.262 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural Evidence for Induced Fit and a Mechanism for Sugar/H(+) Symport in Lacy.

Mirza, O.Guan, L.Verner, G.Iwata, S.Kaback, H.R.

(2006) EMBO J 25: 2038

  • DOI: 10.1038/sj.emboj.7601028
  • Primary Citation of Related Structures:  
    2CFQ, 2CFP

  • PubMed Abstract: 
  • Cation-coupled active transport is an essential cellular process found ubiquitously in all living organisms. Here, we present two novel ligand-free X-ray structures of the lactose permease (LacY) of Escherichia coli determined at acidic and neutral p ...

    Cation-coupled active transport is an essential cellular process found ubiquitously in all living organisms. Here, we present two novel ligand-free X-ray structures of the lactose permease (LacY) of Escherichia coli determined at acidic and neutral pH, and propose a model for the mechanism of coupling between lactose and H+ translocation. No sugar-binding site is observed in the absence of ligand, and deprotonation of the key residue Glu269 is associated with ligand binding. Thus, substrate induces formation of the sugar-binding site, as well as the initial step in H+ transduction.


    Organizational Affiliation

    Department of Biological Sciences, Membrane Protein Crystallography Group, Imperial College London, London, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
LACTOSE PERMEASEA417Escherichia coliMutation(s): 1 
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Major Facilitator Superfamily (MFS) Transporters
Protein: 
LacY Lactose Permease (C154G mutant) without substrate at 2 pH values
Find proteins for P02920 (Escherichia coli (strain K12))
Explore P02920 
Go to UniProtKB:  P02920
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
HG
Query on HG

Download CCD File 
A
MERCURY (II) ION
Hg
BQPIGGFYSBELGY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.95 Å
  • R-Value Free: 0.298 
  • R-Value Work: 0.262 
  • R-Value Observed: 0.262 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 122.47α = 90
b = 122.47β = 90
c = 187.78γ = 90
Software Package:
Software NamePurpose
CNSrefinement
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-03-13
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance