2D4U

Crystal Structure of the ligand binding domain of the bacterial serine chemoreceptor Tsr


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.216 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Ligand specificity determined by differentially arranged common ligand-binding residues in the bacterial amino acid chemoreceptors Tsr and Tar.

Tajima, H.Imada, K.Sakuma, M.Hattori, F.Nara, T.Kamo, N.Homma, M.Kawagishi, I.

(2011) J.Biol.Chem. --: --

  • DOI: 10.1074/jbc.M111.221887
  • Primary Citation of Related Structures:  3ATP

  • PubMed Abstract: 
  • Escherichia coli has closely related amino acid chemoreceptors with distinct ligand specificity, Tar for l-aspartate and Tsr for l-serine. Crystallography of the ligand-binding domain of Tar identified the residues interacting with aspartate, most of ...

    Escherichia coli has closely related amino acid chemoreceptors with distinct ligand specificity, Tar for l-aspartate and Tsr for l-serine. Crystallography of the ligand-binding domain of Tar identified the residues interacting with aspartate, most of which are conserved in Tsr. However, swapping of the nonconserved residues between Tsr and Tar did not change ligand specificity. Analyses with chimeric receptors led us to hypothesize that distinct three-dimensional arrangements of the conserved ligand-binding residues are responsible for ligand specificity. To test this hypothesis, the structures of the apo- and serine-binding forms of the ligand-binding domain of Tsr were determined at 1.95 and 2.5 Å resolutions, respectively. Some of the Tsr residues are arranged differently from the corresponding aspartate-binding residues of Tar to form a high affinity serine-binding pocket. The ligand-binding pocket of Tsr was surrounded by negatively charged residues, which presumably exclude negatively charged aspartate molecules. We propose that all these Tsr- and Tar-specific features contribute to specific recognition of serine and aspartate with the arrangement of the side chain of residue 68 (Asn in Tsr and Ser in Tar) being the most critical.


    Organizational Affiliation

    Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Methyl-accepting chemotaxis protein I
A, B
176Escherichia coli (strain K12)Gene Names: tsr (cheD)
Find proteins for P02942 (Escherichia coli (strain K12))
Go to UniProtKB:  P02942
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.216 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 42.480α = 90.00
b = 55.060β = 93.73
c = 73.330γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
MOSFLMdata reduction
CCP4data scaling
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-11-14
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2011-10-19
    Type: Database references