Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
Doctor of Philosophy Program in Applied Microbiology (International Program), Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.
Toxins (Basel). 2023 Jan 18;15(2):89. doi: 10.3390/toxins15020089.
This study describes an emetic food-borne intoxication associated with a group species and the characterization of the bacterial isolates from the incident in aspects of molecular tying, genetic factors, cytotoxicity, and pathogenic mechanisms relating to emetic illness. Through the polyphasic identification approach, all seven isolates obtained from food and clinical samples were identified as . According to multilocus sequence typing (MLST) analysis, intraspecific diversity was found within the isolates. Four allelic profiles were found, including two previously known STs (ST8 and ST15) and two new STs (ST2804 and ST2805). All isolates harbored gene fragments located in the () gene cluster. The heat-treated culture supernatants of three emetic isolates, FC2, FC7, and FC8, caused vacuolation and exhibited toxicity to Caco-2 cells, with CC values of 56.57, 72.17, and 79.94 µg/mL, respectively. The flow cytometry with the Annexin V/PI assay revealed both apoptosis and necrosis mechanisms, but necrosis was the prominent mechanism that caused Caco-2 cell destruction by FC2, the most toxic isolate.
本研究描述了一起与一组物种相关的呕吐性食源性中毒事件，并从分子关联、遗传因素、细胞毒性以及与呕吐病相关的发病机制等方面对该事件中的细菌分离株进行了特征描述。通过多相鉴定方法，从食物和临床样本中获得的所有 7 个分离株均被鉴定为 。根据多位点序列分型（MLST）分析，发现 分离株内存在种内多样性。发现了四个等位基因谱，包括两个先前已知的 ST（ST8 和 ST15）和两个新的 ST（ST2804 和 ST2805）。所有分离株均携带位于 () 基因簇中的基因片段。经热处理的三个呕吐性 分离株（FC2、FC7 和 FC8）的培养上清液可引起空泡化，并对 Caco-2 细胞表现出毒性，CC 值分别为 56.57、72.17 和 79.94 µg/mL。用 Annexin V/PI 检测法进行流式细胞术分析显示存在凋亡和坏死两种机制，但坏死是导致 Caco-2 细胞被最具毒性的分离株 FC2 破坏的主要机制。
