2XQ2

Structure of the K294A mutant of vSGLT


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.73 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.251 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The Mechanism of Sodium and Substrate Release from the Binding Pocket of Vsglt

Watanabe, A.Choe, S.Chaptal, V.Rosenberg, J.M.Wright, E.M.Grabe, M.Abramson, J.

(2010) Nature 468: 988

  • DOI: 10.1038/nature09580

  • PubMed Abstract: 
  • Membrane co-transport proteins that use a five-helix inverted repeat motif have recently emerged as one of the largest structural classes of secondary active transporters. However, despite many structural advances there is no clear evidence of how io ...

    Membrane co-transport proteins that use a five-helix inverted repeat motif have recently emerged as one of the largest structural classes of secondary active transporters. However, despite many structural advances there is no clear evidence of how ion and substrate transport are coupled. Here we report a comprehensive study of the sodium/galactose transporter from Vibrio parahaemolyticus (vSGLT), consisting of molecular dynamics simulations, biochemical characterization and a new crystal structure of the inward-open conformation at a resolution of 2.7 Å. Our data show that sodium exit causes a reorientation of transmembrane helix 1 that opens an inner gate required for substrate exit, and also triggers minor rigid-body movements in two sets of transmembrane helical bundles. This cascade of events, initiated by sodium release, ensures proper timing of ion and substrate release. Once set in motion, these molecular changes weaken substrate binding to the transporter and allow galactose readily to enter the intracellular space. Additionally, we identify an allosteric pathway between the sodium-binding sites, the unwound portion of transmembrane helix 1 and the substrate-binding site that is essential in the coupling of co-transport.


    Organizational Affiliation

    Department of Physiology, University of California, Los Angeles, Los Angeles, California 90095-1759, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SODIUM/GLUCOSE COTRANSPORTER
A
593Vibrio parahaemolyticusGene Names: sglT
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Solute Sodium Symporter (SSS) Family
Protein: 
vSGLT Sodium Galactose Transporter
Find proteins for P96169 (Vibrio parahaemolyticus)
Go to UniProtKB:  P96169
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
SODIUM/GLUCOSE COTRANSPORTER
B
593Vibrio parahaemolyticusGene Names: sglT
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Solute Sodium Symporter (SSS) Family
Protein: 
vSGLT Sodium Galactose Transporter
Find proteins for P96169 (Vibrio parahaemolyticus)
Go to UniProtKB:  P96169
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
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
UNK
Query on UNK
B
L-PEPTIDE LINKINGC4 H9 N O2

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Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.73 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.251 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 85.300α = 90.00
b = 112.680β = 90.00
c = 238.770γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
HKL-2000data scaling
BUSTERrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-12-08
    Type: Initial release
  • Version 1.1: 2011-08-10
    Type: Database references, Version format compliance