1LJ7

Crystal structure of calcium-depleted human C-reactive protein from perfectly twinned data


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.15 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

The three-dimensional structure of calcium-depleted human C-reactive protein from perfectly twinned crystals.

Ramadan, M.A.Shrive, A.K.Holden, D.Myles, D.A.Volanakis, J.E.DeLucas, L.J.Greenhough, T.J.

(2002) Acta Crystallogr.,Sect.D 58: 992-1001


  • PubMed Abstract: 
  • C-reactive protein is a member of the pentraxin family of oligomeric serum proteins which has been conserved through evolution, homologues having been found in every species in which they have been sought. Human C-reactive protein (hCRP) is the class ...

    C-reactive protein is a member of the pentraxin family of oligomeric serum proteins which has been conserved through evolution, homologues having been found in every species in which they have been sought. Human C-reactive protein (hCRP) is the classical acute-phase reactant produced in large amounts in response to tissue damage and inflammation and is used almost universally as a clinical indicator of infection and inflammation. The role of hCRP in host defence and the calcium-dependent ligand-binding specificity of hCRP for phosphocholine moieties have long been recognized. In order to clarify the structural rearrangements associated with calcium binding, the reported affinity of calcium-depleted hCRP for polycations and other ligands, and the role of calcium in protection against denaturation and proteolysis, the structure of calcium-depleted hCRP has been determined by X-ray crystallography. Crystals of calcium-depleted hCRP are invariably twinned and those suitable for analysis are merohedral type II twins of point group 4 single crystals. The structure has been solved by molecular replacement using the calcium-bound hCRP structure [Shrive et al. (1996), Nature Struct. Biol. 3, 346-354]. It reveals two independent pentamers which form a face-to-face decamer across a dyad near-parallel to the twinning twofold axis. Cycles of intensity deconvolution, density modification (tenfold NCS) and model building, eventually including refinement, give a final R factor of 0.19 (R(free) = 0.20). Despite poor definition in some areas arising from the limited resolution of the data and from the twinning and disorder, the structure reveals the probable mode of twinning and the conformational changes, localized in one of the calcium-binding loops, which accompany calcium binding.


    Organizational Affiliation

    School of Life Sciences, Keele University, Staffordshire ST5 5BG, England.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
C-reactive protein
A, B, C, D, E, F, G, H, I, J
206Homo sapiensGene Names: CRP (PTX1)
Find proteins for P02741 (Homo sapiens)
Go to Gene View: CRP
Go to UniProtKB:  P02741
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.15 Å
  • R-Value Free: 0.199 
  • R-Value Work: 0.186 
  • Space Group: P 43
Unit Cell:
Length (Å)Angle (°)
a = 102.310α = 90.00
b = 102.310β = 90.00
c = 309.230γ = 90.00
Software Package:
Software NamePurpose
CCP4data scaling
MOSFLMdata reduction
CCP4model building
ROTAVATAdata scaling
CCP4phasing
X-PLORrefinement
ROTAVATAdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-06-05
    Type: Initial release
  • Version 1.1: 2008-04-28
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-11
    Type: Refinement description