2QFG

Solution Structure of the N-terminal SCR-1/5 fragment of Complement Factor H.


Experimental Data Snapshot

  • Method: SOLUTION SCATTERING

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

The regulatory SCR-1/5 and cell surface-binding SCR-16/20 fragments of factor H reveal partially folded-back solution structures and different self-associative properties.

Okemefuna, A.I.Gilbert, H.E.Griggs, K.M.Ormsby, R.J.Gordon, D.L.Perkins, S.J.

(2008) J Mol Biol 375: 80-101

  • DOI: https://doi.org/10.1016/j.jmb.2007.09.026
  • Primary Citation of Related Structures:  
    2QFG, 2QFH

  • PubMed Abstract: 

    Factor H (FH) is a plasma glycoprotein that plays a central role in regulation of the alternative pathway of complement. It is composed of 20 short complement regulator (SCR) domains. The SCR-1/5 fragment is required for decay acceleration and cofactor activity, while the SCR-16/20 fragment possesses binding sites for complement C3d and heparin. X-ray scattering and analytical ultracentrifugation showed that SCR-1/5 was monomeric, while SCR-16/20 formed dimers. The Guinier radius of gyration R(G) of 4.3 nm for SCR-1/5 and those of 4.7 nm and about 7.8 nm for monomeric and dimeric SCR-16/20, respectively, showed that their structures are partially folded back and bent. The distance distribution function P(r) showed that SCR-1/5 has a maximum dimension of 15 nm while monomeric and dimeric SCR-16/20 are 17 nm and about 27 nm long, respectively. The sedimentation coefficient of 2.4 S for SCR-1/5 showed no concentration-dependence, while that for SCR-16/20 was 2.8 S for the monomer and 3.9 S for the dimer. Sedimentation equilibrium data showed that SCR-1/5 is monomeric while SCR-16/20 exhibited a weak monomer-dimer equilibrium with a dissociation constant of 16 microM. The constrained scattering and sedimentation modelling of SCR-1/5 and SCR-16/20 showed that partially folded-back and bent flexible SCR arrangements fitted both data sets better than extended linear arrangements, and that the dimer was best modelled in the SCR-16/20 model by an end-to-end association of two SCR-20 domains. The SCR-1/5 and SCR-16/20 models were conformationally similar to the previously determined partially folded-back structure for intact wild-type FH, hence suggesting a partial explanation of the intact FH structure. Comparison of the SCR-16/20 model with the crystal structure of C3b clarified reasons for the distribution of mutations leading to atypical haemolytic uraemic syndrome.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Darwin Building, University College London, Gower Street, London WC1E 6BT, UK.


Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Complement factor H312Homo sapiensMutation(s): 0 
Gene Names: CFHHFHF1HF2
UniProt & NIH Common Fund Data Resources
Find proteins for P08603 (Homo sapiens)
Explore P08603 
Go to UniProtKB:  P08603
PHAROS:  P08603
GTEx:  ENSG00000000971 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP08603
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION SCATTERING

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-09-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-10-18
    Changes: Refinement description
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references