1q0p
From Proteopedia
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A domain of Factor B
Contents |
Overview
Complement factor B is a 90 kDa protein consisting of three domains: a, three-module complement control protein, a von Willebrand factor A domain, and a C-terminal serine protease (SP) domain that adopts a default, inactive (zymogen) conformation. The interaction between factor B and, pathogen-bound C3b is mediated by its A domain, triggering a, conformational change in factor B that ultimately creates the "C3, convertase" of the alternative complement pathway. We report the crystal, structure of the A domain from factor B and show that it contains an, integrin-like MIDAS motif that adopts the "open" conformation typical of, integrin-ligand complexes, with an acidic residue (provided by a, fortuitous crystal contact) completing the coordination of the metal ion., Modeling studies indicate that the factor B A domain can also adopt the, closed conformation, supporting the hypothesis that an "integrin-like, switch" is conserved in complement proteins and perhaps in 60 other A, domains found within the human proteome.
Disease
Known diseases associated with this structure: Macular degeneration, age-related, reduced risk of OMIM:[138470]
About this Structure
1Q0P is a Single protein structure of sequence from Homo sapiens with MN as ligand. Active as Alternative-complement-pathway C3/C5 convertase, with EC number 3.4.21.47 Full crystallographic information is available from OCA.
Reference
Crystal structure of the A domain from complement factor B reveals an integrin-like open conformation., Bhattacharya AA, Lupher ML Jr, Staunton DE, Liddington RC, Structure. 2004 Mar;12(3):371-8. PMID:15016353
Page seeded by OCA on Mon Nov 12 18:49:16 2007
