Abstract

Enterococcus faecalis are ubiquitous micro-organisms which are widely used in fermented food or probiotic industry. However, they are also associated with nosocomial infections and rank among the top three nosocomial bacterial pathogens. Some virulence factors were proposed which could strongly enhance their pathogenicity. In our study, three virulence-related genes ace, gelE and efaA were found in E. faecalis SL22 which was isolated from raw milk. The expression of these genes was examined in response to different stress factors like NaCl, pH and gentamycin sulfate by using real-time PCR. Significant differences in expression level were influenced by the environment factors, which suggests that these stress factors should be taken into consideration during the selection of enterococci for use in foods or as probiotics.

Keywords:

E. faecalis, expression level, stress factor, virulence-related genes,

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Competing interests

The authors have no competing interests.

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