1AOH

SINGLE COHESIN DOMAIN FROM THE SCAFFOLDING PROTEIN CIPA OF THE CLOSTRIDIUM THERMOCELLUM CELLULOSOME


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Work: 0.194 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The crystal structure of a type I cohesin domain at 1.7 A resolution.

Tavares, G.A.Beguin, P.Alzari, P.M.

(1997) J.Mol.Biol. 273: 701-713

  • DOI: 10.1006/jmbi.1997.1326

  • PubMed Abstract: 
  • The quaternary organization of the cellulosome, a multi-enzymatic extracellular complex produced by cellulolytic bacteria, depends on specific interactions between dockerin domains, double EF-hand subunits carried by the catalytic components, and coh ...

    The quaternary organization of the cellulosome, a multi-enzymatic extracellular complex produced by cellulolytic bacteria, depends on specific interactions between dockerin domains, double EF-hand subunits carried by the catalytic components, and cohesin domains, individual receptor subunits linearly arranged within a non-catalytic scaffolding polypeptide. Cohesin-dockerin complexes with distinct specificities are also thought to mediate the attachment of cellulosomes to the cell membrane. We report here the crystal structure of a single cohesin domain from the scaffolding protein of Clostridium thermocellum. The cohesin domain folds into a nine-stranded beta-sandwich with an overall "jelly roll" topology, similar to that observed in bacterial cellulose-binding domains. Surface-exposed patches of conserved residues promote extensive intermolecular contacts in the crystal, and suggest a possible binding target for the EF-hand pair of the cognate dockerin domain. Comparative studies of cohesin domains indicate that, in spite of low sequence similarities and different functional roles, all cohesin domains share a common nine-stranded beta-barrel fold stabilized by a conserved hydrophobic core. The formation of stable cohesin-dockerin complexes requires the presence of Ca2+. However, the structure of the cohesin domain reported here reveals no obvious Ca2+-binding site, and previous experiments have failed to detect high affinity binding of Ca2+ to the unliganded dockerin domain of endoglucanase CelD. Based on structural and biochemical evidence, we propose a model of the cohesin-dockerin complex in which the dockerin domain requires complexation with its cohesin partner for protein stability and high-affinity Ca2+ binding.


    Related Citations: 
    • Subcloning of a DNA Fragment Encoding a Single Cohesin Domain of the Clostridium Thermocellum Cellulosome-Integrating Protein Cipa: Purification, Crystallization, and Preliminary Diffraction Analysis of the Encoded Polypeptide
      Beguin, P.,Raynaud, O.,Chaveroche, M.K.,Dridi, A.,Alzari, P.M.
      (1996) Protein Sci. 5: 1192


    Organizational Affiliation

    Unité d'Immunologie Structurale (URA 1961 CNRS), Paris, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CELLULOSOME-INTEGRATING PROTEIN CIPA
A, B
147Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)Gene Names: cipA
Find proteins for Q06851 (Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372))
Go to UniProtKB:  Q06851
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Work: 0.194 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 37.840α = 90.00
b = 80.500β = 90.00
c = 93.240γ = 90.00
Software Package:
Software NamePurpose
X-PLORrefinement
DENZOdata reduction
X-PLORphasing
X-PLORmodel building
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1998-07-08
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance