2ok5
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Factor B is the central protease of the complement system of immune | + | Factor B is the central protease of the complement system of immune defense. Here, we present the crystal structure of human factor B at 2.3-A resolution, which reveals how the five-domain proenzyme is kept securely inactive. The canonical activation helix of the Von Willebrand factor A (VWA) domain is displaced by a helix from the preceding domain linker. The two helices conformationally link the scissile-activation peptide and the metal ion-dependent adhesion site required for binding of the ligand C3b. The data suggest that C3b binding displaces the three N-terminal control domains and reshuffles the two central helices. Reshuffling of the helices releases the scissile bond for final proteolytic activation and generates a new interface between the VWA domain and the serine protease domain. This allosteric mechanism is crucial for tight regulation of the complement-amplification step in the immune response. |
| + | |||
| + | ==Disease== | ||
| + | Known diseases associated with this structure: Macular degeneration, age-related, reduced risk of OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=138470 138470]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Daha, M | + | [[Category: Daha, M R.]] |
[[Category: Gomes, L.]] | [[Category: Gomes, L.]] | ||
[[Category: Gros, P.]] | [[Category: Gros, P.]] | ||
[[Category: Hemrika, W.]] | [[Category: Hemrika, W.]] | ||
| - | [[Category: Huizinga, E | + | [[Category: Huizinga, E G.]] |
| - | [[Category: Janssen, B | + | [[Category: Janssen, B J.C.]] |
| - | [[Category: Milder, F | + | [[Category: Milder, F J.]] |
| - | [[Category: Romijn, R | + | [[Category: Romijn, R A.]] |
[[Category: Roos, A.]] | [[Category: Roos, A.]] | ||
[[Category: Schouten, A.]] | [[Category: Schouten, A.]] | ||
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[[Category: von willebrand factor-a domain]] | [[Category: von willebrand factor-a domain]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:19:34 2008'' |
Revision as of 16:19, 21 February 2008
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Human Complement factor B
Contents |
Overview
Factor B is the central protease of the complement system of immune defense. Here, we present the crystal structure of human factor B at 2.3-A resolution, which reveals how the five-domain proenzyme is kept securely inactive. The canonical activation helix of the Von Willebrand factor A (VWA) domain is displaced by a helix from the preceding domain linker. The two helices conformationally link the scissile-activation peptide and the metal ion-dependent adhesion site required for binding of the ligand C3b. The data suggest that C3b binding displaces the three N-terminal control domains and reshuffles the two central helices. Reshuffling of the helices releases the scissile bond for final proteolytic activation and generates a new interface between the VWA domain and the serine protease domain. This allosteric mechanism is crucial for tight regulation of the complement-amplification step in the immune response.
Disease
Known diseases associated with this structure: Macular degeneration, age-related, reduced risk of OMIM:[138470]
About this Structure
2OK5 is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as Alternative-complement-pathway C3/C5 convertase, with EC number 3.4.21.47 Full crystallographic information is available from OCA.
Reference
Factor B structure provides insights into activation of the central protease of the complement system., Milder FJ, Gomes L, Schouten A, Janssen BJ, Huizinga EG, Romijn RA, Hemrika W, Roos A, Daha MR, Gros P, Nat Struct Mol Biol. 2007 Mar;14(3):224-8. Epub 2007 Feb 25. PMID:17310251
Page seeded by OCA on Thu Feb 21 18:19:34 2008
Categories: Alternative-complement-pathway C3/C5 convertase | Homo sapiens | Single protein | Daha, M R. | Gomes, L. | Gros, P. | Hemrika, W. | Huizinga, E G. | Janssen, B J.C. | Milder, F J. | Romijn, R A. | Roos, A. | Schouten, A. | GOL | NAG | Ccp domain | Pro-enzyme | Serine protease domain | Von willebrand factor-a domain
