Wang Huhu, Huang Mingyuan, Zeng Xianming, Peng Bing, Xu Xinglian, Zhou Guanghong
Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing, China.
College of Animal Medicine, Xinjiang Agricultural University, Ürümqi, China.
Front Microbiol. 2020 Feb 28;11:130. doi: 10.3389/fmicb.2020.00130. eCollection 2020.
can resist various stresses and survive during food processing, storage, and distribution, resulting in potential health risks to consumers. Therefore, evaluation of bacterial survival profiles under various environmental stresses is necessary. In this study, the resistance profiles of five isolates [serotypes with Agona, Infantis, Typhimurium, Enteritidis, and a standard strain (ATCC 13076, Enteritidis serotype)] to acidic, hyperosmotic, and oxidative stresses were examined, and the relative expressions of non-coding small RNAs were also evaluated, including , , , , , and , induced by specific stresses. The results indicated that although all tested strains displayed a certain resistance to stresses, there was great diversity in stress resistance among the strains. According to the reduction numbers of cells exposed to stress for 3 h, Enteritidis showed the highest resistance to acidic and hyperosmotic stresses, whereas ATCC 13076 showed the greatest resistance to oxidative stress, with less than 0.1 Log CFU/ml of cell reduction. Greater resistance of cells to acidic, hyperosmotic, and oxidative stresses was observed within 1 h, after 2 h, and from 1 to 2 h, respectively. The relative expression of sRNAs depended on the isolate for each stress; acidic exposure for the tested isolates induced high expression levels of , , , , , and . The sRNA , associated with sigma E and outer membrane protein in bacteria, showed a fold change of greater than 7 in Enteritidis exposed to the tested stresses. and involved in general stress responses and stress adaptation were also induced to show high expression levels of exposed to hyperosmotic stress. Overall, these findings demonstrated that the behaviors of under specific stresses varied according to strain and were likely not related to other profiles. The finding also provided insights into the survival of subjected to short-term stresses and for controlling in the food industry.
能够抵抗各种压力并在食品加工、储存和分销过程中存活下来,从而给消费者带来潜在的健康风险。因此,有必要评估细菌在各种环境压力下的存活情况。在本研究中,检测了五株分离株[阿贡纳、婴儿、鼠伤寒、肠炎血清型以及一株标准菌株(ATCC 13076,肠炎血清型)]对酸性、高渗和氧化应激的抗性情况,还评估了由特定应激诱导的非编码小RNA的相对表达情况,包括、、、、、和。结果表明,尽管所有测试菌株都表现出一定的抗应激能力,但各菌株之间的抗应激能力存在很大差异。根据暴露于应激3小时后的细胞减少数量,肠炎血清型菌株对酸性和高渗应激的抗性最高,而ATCC 13076对氧化应激的抗性最强,细胞减少量小于0.1 Log CFU/ml。分别在1小时内、2小时后以及1至2小时内观察到细胞对酸性、高渗和氧化应激的抗性增强。小RNA的相对表达取决于每种应激下的分离株;测试分离株暴露于酸性环境中会诱导、、、、和的高表达水平。与细菌中的σE和外膜蛋白相关的小RNA在暴露于测试应激的肠炎血清型菌株中显示出大于7倍的变化。参与一般应激反应和应激适应的和在暴露于高渗应激时也被诱导显示出高表达水平。总体而言,这些发现表明,在特定应激下的行为因菌株而异,可能与其他特征无关。这一发现还为短期应激下的存活情况以及食品工业中对的控制提供了见解。