A structural basis for Staphylococcal complement subversion: X-ray structure of the complement-binding domain of Staphylococcus aureus protein Sbi in complex with ligand C3d

DOI: 10.1016/j.molimm.2010.09.017
PMID: 21055811

Authors: Elizabeth A. Clark (University of Bath) , Susan Crennell (University of Bath) , Abhisehk Upadhyay (University of Bath) , Alexey V. Zozulya (EMBL) , Julia D. Mackay (University of Bath) , Dmitri Svergun (EMBL) , Stefan Bagby (University of Bath) , Jean M. H. Van Den Elsen (University of Bath)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Molecular Immunology

State: Published (Approved)
Published: November 2010

Abstract: The structure of the complement-binding domain of Staphylococcus aureus protein Sbi (Sbi-IV) in complex with ligand C3d is presented. The 1.7 Å resolution structure reveals the molecular details of the recognition of thioester-containing fragment C3d of the central complement component C3, involving interactions between residues of Sbi-IV helix ?2 and the acidic concave surface of C3d. The complex provides a structural basis for the binding preference of Sbi for native C3 over C3b and explains how Sbi-IV inhibits the interaction between C3d and complement receptor 2. A second C3d binding site on Sbi-IV is identified in the crystal structure that is not observed in related S. aureus C3 inhibitors Efb-C and Ehp. This binding mode perhaps hints as to how Sbi-IV, as part of Sbi, forms a C3b–Sbi adduct and causes futile consumption of C3, an extraordinary aspect of Sbi function that is not shared by any other known Staphylococcal complement inhibitor.

Journal Keywords: Amino; Bacterial; Carrier; Complement; Crystallography; X-Ray; Humans; Ligands; Magnetic; Models; Molecular; Protein; Secondary; Protein; Tertiary; Scattering; Small; Staphylococcus; Structure-Activity; Surface; Titrimetry

Diamond Keywords: Bacteria

Subject Areas: Biology and Bio-materials, Medicine


Instruments: I04-Macromolecular Crystallography

Added On: 11/11/2010 13:53

Documents:
1-s2.0-S016158901000578X-main.pdf

Discipline Tags:

Pathogens Infectious Diseases Health & Wellbeing Structural biology Drug Discovery Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)