Avaliação do potencial patogênico de isolados de Escherichia Coli encontrados em mananciais usados na produção de queijo Minas Artesanal na Serra da Canastra

The Canastra Artisanal Minas Cheese (QMAC) is a cultural and economic heritage of the state of Minas Gerais, traditionally produced from raw milk. Some production units rely on spring water for utensil sanitation and cheese handling, which represents a potential risk of microbiological contamination of the product. Strains of the bacterium Escherichia coli may harbor virulence genes that confer pathogenic potential, including toxins associated with diarrheal diseases and severe conditions such as Hemolytic Uremic Syndrome; moreover, E. coli is widely used as a classical indicator of fecal contamination in milk and dairy products.This study evaluated 160 genetically distinct E. coli isolates obtained from 12 springs used by QMAC producers located in the surroundings of the Serra da Canastra National Park, with the objective of investigating the presence of the virulence genes stx1, stx2, cdt, estI, and eltA. The results showed a low prevalence of virulence genes: estI (11.9%), cdt (5.6%), and only a single detection of stx1 (0.6%). The stx2 and eltA genes were not detected in any of the 160 isolates analyzed. Despite the low prevalence, the detection of genes associated with toxin production indicates the circulation of strains with pathogenic potential in the evaluated water sources, reinforcing the need for continuous monitoring of water quality and for improvements in water management practices in QMAC production. The findings also demonstrate that current microbiological criteria, based solely on coliform counts, do not address the assessment of the virulence potential of the strains present, underscoring the ongoing need to revise monitoring protocols and regulatory frameworks.