2V8N

Wild-type Structure of Lactose Permease


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.6 Å
  • R-Value Free: 0.333 
  • R-Value Work: 0.294 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural Determination of Wild-Type Lactose Permease.

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

(2007) Proc.Natl.Acad.Sci.USA 104: 15294

  • DOI: 10.1073/pnas.0707688104

  • PubMed Abstract: 
  • Here we describe an x-ray structure of wild-type lactose permease (LacY) from Escherichia coli determined by manipulating phospholipid content during crystallization. The structure exhibits the same global fold as the previous x-ray structures of a m ...

    Here we describe an x-ray structure of wild-type lactose permease (LacY) from Escherichia coli determined by manipulating phospholipid content during crystallization. The structure exhibits the same global fold as the previous x-ray structures of a mutant that binds sugar but cannot catalyze translocation across the membrane. LacY is organized into two six-helix bundles with twofold pseudosymmetry separated by a large interior hydrophilic cavity open only to the cytoplasmic side and containing the side chains important for sugar and H(+) binding. To initiate transport, binding of sugar and/or an H(+) electrochemical gradient increases the probability of opening on the periplasmic side. Because the inward-facing conformation represents the lowest free-energy state, the rate-limiting step for transport may be the conformational change leading to the outward-facing conformation.


    Organizational Affiliation

    Department of Physiology, University of California, Los Angeles, CA 90095-1662, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
LACTOSE PERMEASE
A, B
417Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: lacY
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Major Facilitator Superfamily (MFS) Transporters
Protein: 
LacY Lactose Permease Transporter (C154G mutant)
Find proteins for P02920 (Escherichia coli (strain K12))
Go to UniProtKB:  P02920
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.6 Å
  • R-Value Free: 0.333 
  • R-Value Work: 0.294 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 101.370α = 90.00
b = 127.400β = 90.00
c = 188.460γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSphasing
CNSrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-09-11
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance