Collagen-like proteins of pathogenic streptococci
Slawomir Lukomski1, Beth A Bachert1, Flavia Squeglia2
1Department of Microbiology, Immunology, and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, 26506, USA.
Molecular Microbiology
|December 21, 2016
Summary
Streptococcal collagen-like (Scl) proteins are key virulence factors in pathogenic bacteria. These homotrimeric proteins anchor to the cell wall and mediate bacterial adhesion and immune evasion in both tissue and blood environments.
Area of Science:
- Microbiology
- Structural Biology
- Protein Science
Background:
- Collagen-like domains, defined by Gly-X-Y triplet repeats, are ubiquitous in life.
- Streptococcal collagen-like (Scl) proteins are prevalent in pathogenic streptococci, including Streptococcus pyogenes.
Purpose of the Study:
- To investigate the structure, function, and pathogenic roles of Scl proteins.
- To understand the ligand-binding properties of Scl proteins in different host environments.
Main Methods:
- Bioinformatic analyses to determine protein structure and relationships.
- Experimental studies to characterize Scl protein function and interactions.
Main Results:
- Scl proteins are homotrimeric and cell wall-anchored, featuring a collagenous domain and variable non-collagenous domains.
- Scl1 proteins from Streptococcus pyogenes exhibit distinct ligand binding in tissue (wound microenvironment, biofilm formation, neutrophil extracellular trap evasion) and blood (complement, coagulation factors, lipoproteins).
Conclusions:
- Scl proteins represent a large family of structurally related surface proteins.
- These proteins contribute significantly to streptococcal colonization and pathogenesis in hosts.
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