4APS

Crystal structure of a POT family peptide transporter in an inward open conformation.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.3 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.272 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Alternating Access Mechanism in the Pot Family of Oligopeptide Transporters.

Solcan, N.Kwok, J.Fowler, P.W.Cameron, A.D.Drew, D.Iwata, S.Newstead, S.

(2012) Embo J. 31: 3411

  • DOI: 10.1038/emboj.2012.157

  • PubMed Abstract: 
  • Short chain peptides are actively transported across membranes as an efficient route for dietary protein absorption and for maintaining cellular homeostasis. In mammals, peptide transport occurs via PepT1 and PepT2, which belong to the proton-depende ...

    Short chain peptides are actively transported across membranes as an efficient route for dietary protein absorption and for maintaining cellular homeostasis. In mammals, peptide transport occurs via PepT1 and PepT2, which belong to the proton-dependent oligopeptide transporter, or POT family. The recent crystal structure of a bacterial POT transporter confirmed that they belong to the major facilitator superfamily of secondary active transporters. Despite the functional characterization of POT family members in bacteria, fungi and mammals, a detailed model for peptide recognition and transport remains unavailable. In this study, we report the 3.3-Å resolution crystal structure and functional characterization of a POT family transporter from the bacterium Streptococcus thermophilus. Crystallized in an inward open conformation the structure identifies a hinge-like movement within the C-terminal half of the transporter that facilitates opening of an intracellular gate controlling access to a central peptide-binding site. Our associated functional data support a model for peptide transport that highlights the importance of salt bridge interactions in orchestrating alternating access within the POT family.


    Organizational Affiliation

    Department of Biochemistry, University of Oxford, Oxford, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
DI-OR TRIPEPTIDE H+ SYMPORTER
A, B
491Streptococcus thermophilus (strain ATCC BAA-250 / LMG 18311)Mutation(s): 0 
Gene Names: dtpT
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Major Facilitator Superfamily (MFS) Transporters
Protein: 
PepTSt Oligopeptide-proton symporter (POT family)
Find proteins for Q5M4H8 (Streptococcus thermophilus (strain ATCC BAA-250 / LMG 18311))
Go to UniProtKB:  Q5M4H8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CD
Query on CD

Download SDF File 
Download CCD File 
B
CADMIUM ION
Cd
WLZRMCYVCSSEQC-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.3 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.272 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 89.390α = 90.00
b = 112.990β = 90.00
c = 215.490γ = 90.00
Software Package:
Software NamePurpose
Aimlessdata scaling
MOSFLMdata reduction
SHARPphasing
BUSTERrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-06-13
    Type: Initial release
  • Version 1.1: 2012-08-29
    Type: Database references
  • Version 1.2: 2012-10-31
    Type: Other