Report

X-ray Crystal Structure of C3d: A C3 Fragment and Ligand for Complement Receptor 2

Science  22 May 1998:
Vol. 280, Issue 5367, pp. 1277-1281
DOI: 10.1126/science.280.5367.1277

You are currently viewing the abstract.

View Full Text

Via your Institution

Log in through your institution

Log in through your institution


Abstract

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 α-α 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.

  • * These authors contributed equally to this work.

  • Present address: Centre for Virus Research, Westmead Hospital, University of Sydney, Westmead, NSW 2145, Australia.

  • To whom correspondence should be addressed at the Department of Molecular and Medical Genetics, University of Toronto, Toronto, Ontario, Canada, M5S 1A8. E-mail: james.rini{at}utoronto.ca

View Full Text

Related Content