2I6S

Complement component C2a

2I6S の概要

• エントリーDOI: 10.2210/pdb2i6s/pdb
• 関連するPDBエントリー: 2I6Q
• 分子名称: Complement C2a fragment, beta-D-mannopyranose-(1-3)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[beta-L-fucopyranose-(1-6)]2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• 機能のキーワード: serine protease domain, von willebrand factor-a domain, hydrolase
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Secreted: P06681
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 60650.52

構造登録者

Milder, F.J.,Raaijmakers, H.C.A.,Vandeputte, D.A.A.,Schouten, A.,Huizinga, E.G.,Romijn, R.A.,Hemrika, W.,Roos, A.,Daha, M.R.,Gros, P. (登録日: 2006-08-29, 公開日: 2006-10-17, 最終更新日: 2024-12-25)

主引用文献

Milder, F.J.,Raaijmakers, H.C.,Vandeputte, M.D.,Schouten, A.,Huizinga, E.G.,Romijn, R.A.,Hemrika, W.,Roos, A.,Daha, M.R.,Gros, P.
Structure of complement component c2a: implications for convertase formation and substrate binding.
Structure, 14:1587-1597, 2006

PubMed Abstract: 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.

PubMed: 17027507
DOI: 10.1016/j.str.2006.08.008

実験手法

X-RAY DIFFRACTION (2.7 Å)