2ATY

Complement receptor chimaeric conjugate CR2-Ig


Experimental Data Snapshot

  • Method: SOLUTION SCATTERING

wwPDB Validation 3D Report Full Report


This is version 1.5 of the entry. See complete history

Literature

Extended Flexible Linker Structures in the Complement Chimaeric Conjugate CR2-Ig by Scattering, Analytical Ultracentrifugation and Constrained Modelling: Implications for Function and Therapy.

Gilbert, H.E.Aslam, M.Guthridge, J.M.Holers, V.M.Perkins, S.J.

(2006) J.Mol.Biol. 356: 397-412

  • DOI: 10.1016/j.jmb.2005.11.050

  • PubMed Abstract: 
  • Complement receptor 2 (CR2; CD21) is a membrane-bound regulator of complement activation, being comprised of 15 or 16 short complement repeat (SCR) domains. A recombinant glycosylated human CR2 SCR 1-2 domain pair was engineered with the Fc fragment ...

    Complement receptor 2 (CR2; CD21) is a membrane-bound regulator of complement activation, being comprised of 15 or 16 short complement repeat (SCR) domains. A recombinant glycosylated human CR2 SCR 1-2 domain pair was engineered with the Fc fragment of a mouse IgG1 antibody to create a chimaera CR2-Ig containing the major ligand binding domains. Such a chimaera has therapeutic potential as a complement inhibitor or immune modulator. X-ray and neutron scattering and analytical ultracentrifugation identified its domain structure in solution, and provided a comparison with controversial folded-back crystal structures for deglycosylated CR2 SCR 1-2. The radius of gyration R(G) of CR2-Ig was determined to be 5.39(+/-0.14) nm and 5.29(+/-0.01) nm by X-ray and neutron scattering, respectively. The maximum dimension of CR2-Ig was determined to be 17 nm. The molecular mass of CR2-Ig ranged between 101,000 Da and 107,000 Da as determined by neutron scattering and sedimentation equilibrium, in good agreement with the sequence-derived value of 106,600 Da. Sedimentation velocity gave a sedimentation coefficient of 4.49(+/-0.11) S. Stereochemically complete models for CR2-Ig were constructed from crystal structures for the CR2 SCR 1-2 and mouse IgG1 Fc fragments. The two SCR domains and the Fc fragment were joined by randomised conformational peptides. The analysis of 35,000 possible CR2-Ig models showed that only those models in which the two SCR domains were arranged in an open V-shape in random orientations about the Fc fragment accounted for the scattering and sedimentation data. It was not possible to define one single conformational family of Fab-like fragment relative to the Fc fragment. This flexibility is attributed to the relatively long linker sequence and the absence of the antibody light chain from CR2-Ig. The modelling also confirmed that the structure of CR2 SCR 1-2 is more extended in solution than in its crystal structure.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Darwin Building, University College London, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Complement receptor chimeric conjugate CR2-Ig
A, B
376Mus musculusHomo sapiens
This entity is chimeric
Mutation(s): 0 
Gene Names: Ighg1 (Igh-4), CR2 (C3DR)
Find proteins for P01868 (Mus musculus)
Go to UniProtKB:  P01868
Find proteins for P20023 (Homo sapiens)
Go to Gene View: CR2
Go to UniProtKB:  P20023
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION SCATTERING
Software Package:
Software NamePurpose
COLETTEdata reduction
GNOMmodel building
OTOKOdata scaling
GNOMphasing
OTOKOdata reduction
SCTPLphasing
SCTPL7model building
SPOLLYdata reduction
Insight IImodel building
SPOLLYdata scaling
COLETTEdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-01-31
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-06-21
    Type: Database references, Source and taxonomy
  • Version 1.4: 2017-10-11
    Type: Refinement description
  • Version 1.5: 2018-06-13
    Type: Data collection