3FXB

Crystal structure of the ectoine-binding protein UehA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.218 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The crystal structure of UehA in complex with ectoine-A comparison with other TRAP-T binding proteins.

Lecher, J.Pittelkow, M.Zobel, S.Bursy, J.Bonig, T.Smits, S.H.Schmitt, L.Bremer, E.

(2009) J.Mol.Biol. 389: 58-73

  • DOI: 10.1016/j.jmb.2009.03.077

  • PubMed Abstract: 
  • Substrate-binding proteins or extracellular solute receptors (ESRs) are components of both ABC (ATP binding cassette) and TRAP-T (tripartite ATP-independent periplasmic transporter). The TRAP-T system UehABC from Silicibacter pomeroyi DSS-3 imports t ...

    Substrate-binding proteins or extracellular solute receptors (ESRs) are components of both ABC (ATP binding cassette) and TRAP-T (tripartite ATP-independent periplasmic transporter). The TRAP-T system UehABC from Silicibacter pomeroyi DSS-3 imports the compatible solutes ectoine and 5-hydroxyectoine as nutrients. UehA, the ESR of the UehABC operon, binds both ectoine and 5-hydroxyectoine with high affinity (K(d) values of 1.4+/-0.1 and 1.1+/-0.1 microM, respectively) and delivers them to the TRAP-T complex. The crystal structure of UehA in complex with ectoine was determined at 2.9-A resolution and revealed an overall fold common for all ESR proteins from TRAP systems determined so far. A comparison of the recently described structure of TeaA from Halomonas elongata and an ectoine-binding protein (EhuB) from an ABC transporter revealed a conserved ligand binding mode that involves both directed and cation-pi interactions. Furthermore, a comparison with other known TRAP-T ESRs revealed a helix that might act as a selectivity filter imposing restraints on the ESRs that fine-tune ligand recognition and binding and finally might determine the selection of the cognate substrate.


    Organizational Affiliation

    Institute of Biochemistry, Heinrich-Heine-University Duesseldorf, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRAP dicarboxylate transporter, DctP subunit
A, B
326Ruegeria pomeroyi (strain ATCC 700808 / DSM 15171 / DSS-3)Mutation(s): 0 
Gene Names: uehA
Find proteins for Q5LUA7 (Ruegeria pomeroyi (strain ATCC 700808 / DSM 15171 / DSS-3))
Go to UniProtKB:  Q5LUA7
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
4CS
Query on 4CS

Download SDF File 
Download CCD File 
A, B
(4S)-2-METHYL-1,4,5,6-TETRAHYDROPYRIMIDINE-4-CARBOXYLIC ACID
ECTOINE
C6 H10 N2 O2
WQXNXVUDBPYKBA-YFKPBYRVSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
4CSKd: 1400 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.9 Å
  • R-Value Free: 0.262 
  • R-Value Work: 0.218 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 63.000α = 90.00
b = 61.300β = 102.60
c = 86.300γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data collection
XDSdata reduction
PHASERphasing
XSCALEdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-05-26
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance