CNE, a collagen-binding protein of Streptococcus equi

Area of Science:

• Veterinary Microbiology
• Bacterial Pathogenesis
• Molecular Biology

Background:

• * Streptococcus equi subspecies equi is a significant equine pathogen responsible for strangles.
• * Virulence factors are crucial for bacterial infection and disease development.

Purpose of the Study:

• * To identify and characterize novel virulence factors in Streptococcus equi subspecies equi.
• * To investigate the role of a newly identified collagen-binding protein (CNE) in bacterial adhesion and pathogenesis.

Main Methods:

• * Bioinformatics analysis to identify the cne gene.
• * Polymerase chain reaction (PCR) for gene amplification.
• * Recombinant protein expression in Escherichia coli.
• * Western ligand blot to assess collagen-binding activity.
• * Inhibition assays to evaluate competitive binding.

Main Results:

• * A novel gene, cne, encoding a collagen-binding protein (CNE) was identified in Streptococcus equi subspecies equi.
• * Recombinant CNE protein demonstrated collagen-binding activity.
• * The N-terminal A domain of CNE was sufficient for collagen binding and competed with CNA from Staphylococcus aureus for binding sites.
• * The cne gene was present in all tested strains of S. equi subspecies equi and S. equi subspecies zooepidemicus.

Conclusions:

• * Protein CNE is a novel, cell surface-anchored collagen-binding protein in Streptococcus equi subspecies equi.
• * CNE is a potential virulence factor contributing to S. equi subspecies equi pathogenesis.
• * The collagen-binding activity of CNE, particularly its A domain, has implications for understanding bacterial adhesion mechanisms.