Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta, Canada, T1K 3M4.
Agriculture and Agri-Food Canada Lacombe Research and Development Centre, 6000 C & E Trail, Lacombe, Alberta T4L 1W1, Canada.
Food Microbiol. 2023 Aug;113:104267. doi: 10.1016/j.fm.2023.104267. Epub 2023 Mar 20.
Sanitizer resistance is being extensively investigated due to the potential for bacterial survival and cross-resistance with other antimicrobials. Similarly, organic acids are being used due to their microbial inactivation potential as well as being generally recognized as safe (GRAS). However, little is known about associations of genetic and phenotypic factors in Escherichia coli related to resistance to sanitizers and organic acids as well as differences between "Top 7" serogroups. Therefore, we investigated 746 E. coli isolates for resistance to lactic acid and two commercial sanitizers based on quaternary ammonium and peracetic acid. Furthermore, we correlated resistance to several genetic markers and investigated 44 isolates using Whole Genome Sequencing. Results indicate that factors related to motility, biofilm formation, and Locus of Heat Resistance played a role in resistance to sanitizers and lactic acid. In addition, Top 7 serogroups significantly differed in sanitizer and acid resistance, with O157 being the most consistently resistant to all treatments. Finally, mutations in rpoA, rpoC, and rpoS genes were observed, in addition to presence of a Gad gene with alpha-toxin formation in all O121 and O145 isolates, which may be related to increased resistance of these serogroups to the acids used in the present study.
由于细菌存活和与其他抗菌药物交叉耐药的可能性，消毒剂耐药性正在被广泛研究。同样，由于具有微生物灭活潜力以及被普遍认为是安全的（GRAS），有机酸也在被使用。然而，关于与消毒剂和有机酸耐药性相关的大肠杆菌遗传和表型因素的关联以及“前 7 大”血清群之间的差异知之甚少。因此，我们调查了 746 株大肠杆菌对乳酸和两种基于季铵盐和过氧乙酸的商业消毒剂的耐药性。此外，我们还将耐药性与几种遗传标记相关联，并使用全基因组测序对 44 株进行了研究。结果表明，与运动性、生物膜形成和耐热性有关的因素在对抗消毒剂和乳酸的耐药性中起作用。此外，前 7 大血清群在消毒剂和酸的耐药性方面存在显著差异，O157 对所有处理的耐药性最为一致。最后，观察到 rpoA、rpoC 和 rpoS 基因的突变，以及所有 O121 和 O145 分离株中 Gad 基因的存在和 alpha 毒素的形成，这可能与这些血清群对本研究中使用的酸的耐药性增加有关。
