Avaliação microbiológica e molecular de Escherichia coli isoladas em carne moída bovina no interior de São Paulo

Abstract

Escherichia coli (E. coli) is a Gram-negative bacterium of the Enterobacteriaceae family with high genetic plasticity. Pathogenic strains produce toxins, adhesins, capsules, biofilms, and β-lactamases, which confer antimicrobial resistance. This study aimed to assess the presence of E. coli in ground beef sold in Presidente Prudente, São Paulo, and to characterize the virulence and resistance genes at the molecular level. A total of 51 samples of ground beef from butcher shops registered with the Health Surveillance Agency were analyzed. Bacterial identification was performed using microbiological, biochemical, and polymerase chain reaction methods. These methods included the detection of the papC, fimH, kpsMTII, fliC, blaTEM, blaSHV, blaCTX-M, and blaOXA genes, as well as phylogenetic classification (groups A, B1, B2, and D). Fifty-five isolates confirmed as E. coli were obtained, predominantly from group B2 (54.5%). The fimH (100%), papC (83.6%), and fliC (80%) genes were the most prevalent. All isolates showed biofilm formation with a weak adherence pattern. Resistance was low, with tetracycline resistance being the most prevalent (12.7%). Most isolates presented multiple resistance genes (mean of 2.27). It is concluded that ground meat can carry virulent and resistant strains of E. coli, highlighting the importance of hygiene measures and continuous microbiological surveillance.