Shiga-Toxin Genes and Genetic Diversity of Escherichia coli Isolated from Pasteurized Cow Milk in Brazil

作者：Hoffmann Simone Aparecida; Pieretti Gabriella Giani; Fiorini Adriana; Patussi Eliana Valeria; Cardoso Rosilene Fressatti; Graton Mikcha Jane Martha

来源：Journal of Food Science, 2014, 79(6): M1175-M1180.

DOI：10.1111/1750-3841.12477

• enterobacterial repetitive intergenic consensus sequence polymerase chain reaction (ERIC-PCR)
• PCR (polymerase chain reaction)
• repetitive extragenic palindromic sequence polymerase chain reaction (REP-PCR)
• Shiga toxin-producing Escherichia coli (STEC)
• virulence genes

This study evaluated the genetic similarity and prevalence of the stx1, stx2, eae, and ehxA genes in Escherichia coli isolated from pasteurized cow milk. Eighty-seven E. coli isolates from pasteurized cow milk from 22 dairies located in northwestern Parana state, Brazil, were analyzed. Genetic similarity was evaluated using enterobacterial repetitive intergenic consensus sequence polymerase chain reaction (ERIC-PCR) and repetitive extragenic palindromic sequence PCR (REP-PCR). E. coli isolates were also analyzed by PCR to investigate the presence of the stx1, stx2, eae, and ehxA genes. ERIC-PCR and REP-PCR clustered 87 bacterial isolates in 76 and 81 genomic profiles, respectively. Both techniques revealed high genetic diversity among the E. coli isolates, confirming the possibility of their use in epidemiological studies. The stx1, stx2, eae, and ehxA virulence genes were not detected in E. coli isolates, indicating a low prevalence of Shiga toxin-producing E. coli in milk produced in the region studied. Practical Application Knowledge about the presence of diarrheagenic Escherichia coli in pasteurized milk is important developing and implementing control measures in milk and dairy production.

• 出版日期2014-6