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1c3d
From Proteopedia
X-RAY CRYSTAL STRUCTURE OF C3D: A C3 FRAGMENT AND LIGAND FOR COMPLEMENT RECEPTOR 2
Overview
Activation and covalent attachment of complement component C3 to pathogens is the key step in complement-mediated host defense. Additionally, the antigen-bound C3d fragment interacts with complement receptor 2 (CR2; also known as CD21) on B cells and thereby contributes to the initiation of an acquired humoral response. The x-ray crystal structure of human C3d solved at 2.0 angstroms resolution reveals an alpha-alpha barrel with the residues responsible for thioester formation and covalent attachment at one end and an acidic pocket at the other. The structure supports a model whereby the transition of native C3 to its functionally active state involves the disruption of a complementary domain interface and provides insight into the basis for the interaction between C3d and CR2.
About this Structure
1C3D is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
X-ray crystal structure of C3d: a C3 fragment and ligand for complement receptor 2., Nagar B, Jones RG, Diefenbach RJ, Isenman DE, Rini JM, Science. 1998 May 22;280(5367):1277-81. PMID:9596584 Page seeded by OCA on Fri May 2 12:16:47 2008
Categories: Homo sapiens | Single protein | Diefenbach, R J. | Isenman, D E. | Jones, R G. | Nagar, B. | Rini, J M. | Alpha-alpha barrel | C3 | C3d | Complement
