Functional and Structural Properties of a Novel Protein and Virulence Factor (sHIP) in Streptococcus pyogenes.
Author
Summary, in English
Streptococcus pyogenes is a significant bacterial pathogen in the human population. The importance of virulence factors for the survival and colonization of S. pyogenes is well established, and many of these factors are exposed to the extracellular environment enabling bacterial interactions with the host. In the present study we quantitatively analyzed and compared S. pyogenes proteins in the growth medium of a strain that is virulent to mice, with a non-virulent strain. Particularly one of these proteins was present at significantly higher levels in stationary growth medium from the virulent strain. We determined the three-dimensional structure of the protein that showed a unique tetrameric organization composed of four helix-loop-helix motifs. Affinity pull-down mass spectrometry analysis in human plasma demonstrated that the protein interacts with histidine-rich glycoprotein (HRG), and the name sHIP (streptococcal Histidine-rich glycoprotein Interacting Protein) is therefore proposed. HRG has antibacterial activity, and when challenged by HRG, sHIP was found to rescue S. pyogenes bacteria. This and the finding that patients with invasive S. pyogenes infection respond with antibody production against sHIP, suggest a role for the protein in S. pyogenes pathogenesis.
Publishing year
2014
Language
English
Pages
18175-18188
Publication/Series
Journal of Biological Chemistry
Volume
289
Issue
26
Links
Document type
Journal article
Publisher
American Society for Biochemistry and Molecular Biology
Topic
- Infectious Medicine
Status
Published
Research group
- Infection Medicine Proteomics
ISBN/ISSN/Other
- ISSN: 1083-351X