Fisher Emilie L, Otto Michael, Cheung Gordon Y C
Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States.
Front Microbiol. 2018 Mar 13;9:436. doi: 10.3389/fmicb.2018.00436. eCollection 2018.
The enterotoxins are a superfamily of secreted virulence factors that share structural and functional similarities and possess potent superantigenic activity causing disruptions in adaptive immunity. The enterotoxins can be separated into two groups; the classical (SEA-SEE) and the newer (SEG-SEY and counting) enterotoxin groups. Many members from both these groups contribute to the pathogenesis of several serious human diseases, including toxic shock syndrome, pneumonia, and sepsis-related infections. Additionally, many members demonstrate emetic activity and are frequently responsible for food poisoning outbreaks. Due to their robust tolerance to denaturing, the enterotoxins retain activity in food contaminated previously with . The genes encoding the enterotoxins are found mostly on a variety of different mobile genetic elements. Therefore, the presence of enterotoxins can vary widely among different isolates. Additionally, the enterotoxins are regulated by multiple, and often overlapping, regulatory pathways, which are influenced by environmental factors. In this review, we also will focus on the newer enterotoxins (SEG-SEY), which matter for the role of as an enteropathogen, and summarize our current knowledge on their prevalence in recent food poisoning outbreaks. Finally, we will review the current literature regarding the key elements that govern the complex regulation of enterotoxins, the molecular mechanisms underlying their enterotoxigenic, superantigenic, and immunomodulatory functions, and discuss how these activities may collectively contribute to the overall manifestation of staphylococcal food poisoning.
肠毒素是一类分泌型毒力因子超家族，它们在结构和功能上具有相似性，并具有强大的超抗原活性，可导致适应性免疫紊乱。肠毒素可分为两组；经典（SEA - SEE）和新型（SEG - SEY及后续编号）肠毒素组。这两组中的许多成员都参与了几种严重人类疾病的发病机制，包括中毒性休克综合征、肺炎和败血症相关感染。此外，许多成员具有催吐活性，经常导致食物中毒暴发。由于它们对变性具有很强的耐受性，肠毒素在先前被污染的食物中仍保持活性。编码肠毒素的基因大多存在于各种不同的可移动遗传元件上。因此，不同分离株中肠毒素的存在差异很大。此外，肠毒素受多种且往往相互重叠的调控途径调节，这些途径受环境因素影响。在本综述中，我们还将重点关注新型肠毒素（SEG - SEY），它们作为肠道病原体的作用很重要，并总结我们目前关于它们在近期食物中毒暴发中流行情况的知识。最后，我们将回顾当前关于控制肠毒素复杂调控的关键要素、其产肠毒素、超抗原和免疫调节功能的分子机制的文献，并讨论这些活性如何共同促成葡萄球菌食物中毒的总体表现。
