Streptogramin resistance patterns and virulence determinants in vancomycin-susceptible enterococci isolated from multi-component deli salads.
OBJECTIVE
This study examined vancomycin-susceptible Enterococcus (VSE) from deli salads for streptogramin resistance and presence of cpd, agg and gelE genes.


RESULTS
Fifteen VSE from retail salads were isolated for identification and antimicrobial susceptibility testing by MicroScan, Etest and agar diffusion. Clinical vancomycin-resistant Enterococcus (n = 32) and animal VSE (n = 17) were included for comparative purposes. Multiplex PCR was used to detect the following genes: agg, gelE, cpd, vatD, vatE and sodA. Results showed fewer streptogramin-susceptible Enterococcus faecium isolated from salad (1/6, 17%) and animals (6/10, 60%) than from clinical (26/29, 90%) sources. A low level of erythromycin susceptibility was detected among salad (2/6, 33%) and animal (3/10, 30%) Ent. faecium isolates. Food and animal VSE demonstrated similarities in antimicrobial resistance profiles. All Enterococcus faecalis carried one or more of the selected genes cpd (40%), gelE (33%) and agg (27%). The vatD or vatE genes were not detected in any of the isolates.


CONCLUSIONS
Experiments demonstrated that streptogramin resistance and virulence genes agg, cpd and gelE are present in enterococci isolated from deli salads.


CONCLUSIONS
This study provides useful information regarding streptogramin resistance and virulence determinants in enterococci from foods associated with multi-component ingredients.
Christensen
E A
EA
Department of Food Science, Rutgers University, New Brunswick, NJ 08901, USA.
Joho
K
K
Matthews
K R
KR
D000818:Animals; D024881:Drug Resistance, Bacterial; D016983:Enterococcus / Q000187:drug effects*; D005516:Food Microbiology; D005798:Genes, Bacterial; D019450:Genes, MDR; D006801:Humans; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction / Q000379:methods; D025361:Streptogramins / Q000494:pharmacology*; D020713:Vancomycin Resistance; D014774:Virulence
D025361:Streptogramins