Download MendeleyStructure of the streptococcal endopeptidase IdeS, a cysteine proteinase with strict specificity for IgG
Wenig, K., Chatwell, L., von Pawel-Rammingen, U., Bjoerck, L., Huber, R., Sondermann, P.(2004) Proc Natl Acad Sci U S A 101: 17371-17376
- PubMed: 15574492
- DOI: https://doi.org/10.1073/pnas.0407965101
- Primary Citation of Related Structures:
1Y08 - PubMed Abstract:
Pathogenic bacteria have developed complex and diverse virulence mechanisms that weaken or disable the host immune defense system. IdeS (IgG-degrading enzyme of Streptococcus pyogenes) is a secreted cysteine endopeptidase from the human pathogen S. pyogenes with an extraordinarily high degree of substrate specificity, catalyzing a single proteolytic cleavage at the lower hinge of human IgG. This proteolytic degradation promotes inhibition of opsonophagocytosis and interferes with the killing of group A Streptococcus. We have determined the crystal structure of the catalytically inactive mutant IdeS-C94S by x-ray crystallography at 1.9-A resolution. Despite negligible sequence homology to known proteinases, the core of the structure resembles the canonical papain fold although with major insertions and a distinct substrate-binding site. Therefore IdeS belongs to a unique family within the CA clan of cysteine proteinases. Based on analogy with inhibitor complexes of papain-like proteinases, we propose a model for substrate binding by IdeS.
Organizational Affiliation:
Department of Structural Research, Max Planck Institute for Biochemistry, D-82152 Martinsried, Germany. wenig@biochem.mpg.de
