2i6q: Difference between revisions
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[[Image:2i6q.gif|left|200px]] | [[Image:2i6q.gif|left|200px]] | ||
'''Complement component C2a''' | {{Structure | ||
|PDB= 2i6q |SIZE=350|CAPTION= <scene name='initialview01'>2i6q</scene>, resolution 2.100Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene> and <scene name='pdbligand=MLI:MALONATE ION'>MLI</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Classical-complement-pathway_C3/C5_convertase Classical-complement-pathway C3/C5 convertase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.43 3.4.21.43] | |||
|GENE= C2a ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | |||
}} | |||
'''Complement component C2a''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
2I6Q is a [ | 2I6Q is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2I6Q OCA]. | ||
==Reference== | ==Reference== | ||
Structure of complement component C2A: implications for convertase formation and substrate binding., Milder FJ, Raaijmakers HC, Vandeputte MD, Schouten A, Huizinga EG, Romijn RA, Hemrika W, Roos A, Daha MR, Gros P, Structure. 2006 Oct;14(10):1587-97. PMID:[http:// | Structure of complement component C2A: implications for convertase formation and substrate binding., Milder FJ, Raaijmakers HC, Vandeputte MD, Schouten A, Huizinga EG, Romijn RA, Hemrika W, Roos A, Daha MR, Gros P, Structure. 2006 Oct;14(10):1587-97. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17027507 17027507] | ||
[[Category: Classical-complement-pathway C3/C5 convertase]] | [[Category: Classical-complement-pathway C3/C5 convertase]] | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
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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 Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 17:26:06 2008'' | ||
Revision as of 15:26, 20 March 2008
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| 2i6q, resolution 2.100Å | |||||||||||||
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| Ligands: | NAG, MN and MLI | ||||||||||||
| Gene: | C2a (Homo sapiens) | ||||||||||||
| Activity: | Classical-complement-pathway C3/C5 convertase, with EC number 3.4.21.43 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
Complement component C2a
Overview
C2a provides the catalytic center to the convertase complexes of the classical and lectin-binding pathways of complement activation. We determined two crystal structures of full-length C2a, with and without a pseudo ligand bound. Both structures reveal a near-active conformation of the catalytic center of the serine protease domains, while the von Willebrand factor A-type domains display an intermediate activation state of helix alpha7 with an open, activated metal-ion-dependent adhesion site. The open adhesion site likely serves to enhance the affinity for the ligand C4b, similar to "inside-out" signaling in integrins. Surprisingly, the N-terminal residues of C2a are buried in a crevice near helix alpha7, indicative of a structural switch between C2 and C2a. Extended loops on the protease domain possibly envelop the protruding anaphylatoxin domain of the substrate C3. Together with a putative substrate-induced completion of the oxyanion hole, this may contribute to the high substrate specificity of the convertases.
Disease
Known diseases associated with this structure: C2 deficiency OMIM:[217000], Macular degeneration, age-related, reduced risk of OMIM:[217000]
About this Structure
2I6Q is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure of complement component C2A: implications for convertase formation and substrate binding., Milder FJ, Raaijmakers HC, Vandeputte MD, Schouten A, Huizinga EG, Romijn RA, Hemrika W, Roos A, Daha MR, Gros P, Structure. 2006 Oct;14(10):1587-97. PMID:17027507
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