Comparison of biofilm production and virulence genes distribution among human and canine isolates of .

Background: is an important human and animal pathogen that can cause a wide range of infections due to numerous virulence factors.

Aims: The aim of this study was to compare biofilm formation ability with different virulence factors such as bacterial motility, genes encoding biofilm associated proteins, and Panton-Valentine leukocidin (PVL) among human and canine isolates of

Methods: A total of 60 human (30 methicillin sensitive (MSSA) and 30 methicillin resistant . (MRSA)) and 17 canine (all MSSA) isolates of were tested for the capability of biofilm production, motility assay, and presence of genes encoding virulence factors: (encoding intercellular adhesion), (encoding biofilm-associated protein), (encoding fibronectin-binding protein A), (encoding collagen-binding protein), and (encoding PVL).

Results: Animal isolates of performed better biofilm production than the human strains (P=0.042), as well as human MSSA compared to the MRSA isolates (P=0.013). Our results showed that , , and genes (67.5%, 66.2%, and 42.9%, respectively) were more prevalent than and genes (0%, and 7.8%, respectively). The gene was significantly more prevalent in human isolates compared to animal isolates (n=31/60 vs. n=2/17, P=0.008), whereas the gene was more frequent in animal isolates than in human ones (n=15/17 vs. n=37/60, P=0.0201). Significant correlations were found between the biofilm formation of animal isolates, and the presence of (P=0.029) and genes (P=0.001).

Conclusion: This study showed a correlation between biofilm production and the presence of certain biofilm-related genes in animal isolates, as well as stronger biofilm production among MSSA human and animal isolates.