INVESTIGATION OF VIRULENCE FACTORS USING PHENOTYPIC AND GENOTYPIC METHODS IN HIGH-LEVEL AMINOGLYCOSIDE RESISTANT ENTEROCOCCI ISOLATED FROM CHEESE

The aim of this study was to investigate the virulence factors using phenotypic and genotypic methods in 54 high-level aminoglycoside resistant (HLAR) enterococci previously isolated from cheese samples. The α-hemolytic (48.15 %), γ-hemolytic (46.30 %), and β-hemolytic (5.55 %) activities phenotypically were determined in HLAR enterococci. Gelatinase activity was detected in only E. faecalis RG22.4, RG26.1, and RG26.2 strains. At least one virulence factor gene was determined using polymerase chain reaction (PCR) in HLAR isolates except E. faecium RS32.2. The most frequently virulence genes were detected as ccf (88.89 %), efaAfs (85.19 %), acm (77.78 %), gelE (59.2 %), cpd (51.85 %), and espfs (50 %) in HLAR enterococci isolates. As a result of phenotypic and genotypic tests, silent gelE genes were found in 30 HLAR enterococci isolates. Detection of high frequency of virulence factor genes in HLAR enterococci strains isolated from cheese is worrying for consumer health