1NWV image
Deposition Date 2003-02-07
Release Date 2003-04-22
Last Version Date 2024-10-16
Entry Detail
PDB ID:
1NWV
Title:
SOLUTION STRUCTURE OF A FUNCTIONALLY ACTIVE COMPONENT OF DECAY ACCELERATING FACTOR
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Host Organism:
Method Details:
Experimental Method:
Conformers Calculated:
190
Conformers Submitted:
42
Selection Criteria:
structures with the lowest energy
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Complement decay-accelerating factor
Gene (Uniprot):CD55
Chain IDs:A
Chain Length:129
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation
Solution structure of a functionally active fragment of decay-accelerating factor
Proc.Natl.Acad.Sci.USA 100 4718 4723 (2003)
PMID: 12672958 DOI: 10.1073/pnas.0730844100

Abstact

The second and third modules of human decay accelerating factor (DAF) are necessary and sufficient to accelerate decay of the classical pathway (CP) convertase of complement. No structure of a mammalian protein with decay-accelerating activity has been available to date. We therefore determined the solution structure of DAF modules 2 and 3 (DAF approximately 2,3). Structure-guided analysis of 24 mutants identified likely contact points between DAF and the CP convertase. Three (R96, R69, and a residue in the vicinity of L171) lie on DAF approximately 2,3's concave face. A fourth, consisting of K127 and nearby R100, is on the opposite face. Regions of module 3 remote from the semiflexible 2-3 interface seem not to be involved in binding to the CP convertase. DAF thus seems to occupy a groove on the CP convertase such that both faces of DAF close to the 2-3 junction (including a positively charged region that encircles the protein at this point) interact simultaneously. Alternative pathway convertase interactions with DAF require additional regions of CCP 3 lying away from the 2-3 interface, consistent with the established additional requirement of module 4 for alternative pathway regulation.

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Primary Citation of related structures