| Abstrakt: |
AbstractThe objective of this work was to investigate the antimicrobial resistance in Listeriaspp. isolated from food of animal origin. A total of 50 Listeriastrains isolated from meat and dairy products, consisting of 7 Listeria monocytogenesand 43 Listeria innocuastrains, were characterized for antimicrobial susceptibility against nine antimicrobials. The strains were screened by real-time PCR for the presence of antimicrobial resistance genes: tet M, tet L, mef A, msr A, erm A, erm B, lnu A, and lnu B. Multidrug resistance was identified in 27 Listeriastrains, 4 belonging to L. monocytogenes. Resistance to clindamycin was the most common resistance phenotype and was identified in 45 Listeriastrains; the mechanisms of resistance are still unknown. A medium prevalence of resistance to tetracycline (15 and 9 resistant and intermediate strains) and ciprofloxacin (13 resistant strains) was also found. Tet Mwas detected in Listeriastrains with reduced susceptibility to tetracycline, providing evidence that both L. innocuaand L. monocytogenesdisplayed acquired resistance. The presence of antimicrobial resistance genes in L. innocuaand L. monocytogenesindicates that these genes may be transferred to commensal and pathogenic bacteria via the food chain; besides this, antibiotic resistance in L. monocytogenescould compromise the effective treatment of listeriosis in humans. |
