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Published on: October 7, 2025
Identification and characterization of enterococci from bryndza cheese
D Jurkovic1, L Krizková, R Dusinský
1Institute of Cell Biology, Faculty of Natural Sciences, Comenius University, Bratislava, Slovak Republic.
Letters in Applied Microbiology
|May 19, 2006
Summary
Enterococcus faecium dominates enterococci in sheep milk bryndza cheese, particularly in winter. No vancomycin resistance genes (vanA, vanB) were detected in any Enterococcus species analyzed.
Area of Science:
- Food microbiology
- Bacterial genetics
- Dairy science
Background:
- Enterococci are common in dairy products, including sheep milk bryndza cheese.
- Understanding the enterococcal species composition and their potential for antibiotic resistance and virulence is crucial for food safety.
- Seasonal variations may influence the microflora in cheese.
Purpose of the Study:
- To identify enterococci in bryndza cheese.
- To compare seasonal differences in enterococcal microflora composition.
- To assess the presence of vancomycin resistance and virulence genes.
Main Methods:
- Isolation and identification of Enterococcus species using phenotypic methods and commercial biochemical sets.
- Confirmation of species identification via PCR with species-specific primers.
- Detection of vancomycin resistance genes (vanA, vanB) and virulence determinants (gelE, agg, cyl genes) using PCR.
Main Results:
- Enterococcus faecium was the dominant species (177 isolates), followed by Enterococcus durans (59) and Enterococcus faecalis (41) among 308 Enterococcus strains.
- Vancomycin resistance genes vanA and vanB were not detected in any isolates.
- The virulence gene gelE was found in 20 E. faecalis isolates, agg in 4 isolates, and cytolysin genes in 7 isolates, though phenotypic expression was limited.
- Enterococcus faecium prevalence was highest in winter cheese samples.
Conclusions:
- Enterococcus faecium is the predominant enterococcal species in bryndza cheese, with higher prevalence during winter.
- No vancomycin resistance (vanA, vanB genes) was found in the analyzed enterococci from bryndza cheese.
- This study provides the first report on enterococcal microflora in bryndza cheese and its associated resistance and virulence determinants.
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