MOLECULAR ANALYSIS OF STAPHYLOCOCCAL TYPE C ENTEROTOXINS

在美国，金黄色葡萄球菌是导致食物中毒的主要原因。葡萄球菌性食物中毒是一种伴有呕吐和腹泻的中毒。我们的实验室关注葡萄球菌肠毒素的结构-功能分析，从而确定引起胃肠道症状所需的功能区域。这项工作的另一个重要方面是，它使我们能够区分肠毒性和超抗原分子区域。与肠毒性活动最密切相关的区域是二硫环周围的区域。我们在这个区域构建了几个突变，并表明所产生的蛋白质在口服给尾猴时是无毒的。我们将在明年扩展这项工作，以确定是否可以通过使用这些毒素中的几种作为口服疫苗在胃肠道中诱导保护性免疫。

Staphylococcus aureus is a major cause of food poisoning in the United States. Staphylococcal food poisoning is an intoxication associated with vomiting and diarrhea. Our lab is concerned with structure-function analysis of staphylococcal enterotoxins, allowing the identification of functional regions necessary to cause symptoms in the gastrointestinal tract. Another important aspect of this work is that it allows us to differentiate between enterotoxic and superantigenic molecular regions. The region implicated most strongly in enterotoxic activity is the area around the disulfide loop. We constructed several mutations in this region and have shown that the resulting proteins are nontoxic when administered orally to pigtailed macaques. We will extend this work during the next year to determine whether protective immunity can be induced in the gastrointestinal tract by using several of these toxins as oral vaccines.