Staphylococcal superantigen and anthrax inhibitors

长期目标是了解耐甲氧西林金黄色葡萄球菌（MRSA）的发病机制 分泌超抗原（SAg）如肠毒素（SE）B或C、SE样Q和中毒性休克综合征 毒素-1（TSST-1）和炭疽杆菌。MRSA是新兴的病原体，其SAg类别B选择 剂. B。炭疽是A类选择性病原体。我们已经收集了两个项目，如下所述。 项目1。抑制超抗原功能的高亲和力分子。当在体内产生或当 有目的地施用的SAg是异常毒性的（剂量为0.1ng/人时的TSS症状）。最 与流感后TSS、坏死性肺炎和暴发性紫癜相关的MRSA产生SEB， SEC、SE类Q和TSST-1。具体目标1。为了工程化和表征V（3-T细胞受体（TCR）区域 其以高亲和力结合SAg并中和它们，最重要的是SEB、SEC、SE样Q和TSST-1。 具体目标2。设计和表征与SAgs高亲和力结合的MHC II区， 中和他们的活动。具体目标3。为了测试可溶性Vp-TCR和MHCMs中和Vp-TCR的能力， SAgs的体外和家兔体内活性。项目2：受调节的SrrA-SrrB和BrrA-BrrB的抑制剂 外毒素生产。MRSA需要氧气来产生外毒素。这一观察结果导致了一种 MRSA外毒素产生的氧气控制所需的“主开关”双组分系统。这 系统，命名为srrA-srrB，在低氧条件下抑制外毒素的产生和毒力。 最近，在B.炭疽菌BrrA-BrrB。BrrA-BrrB功能诱导炭疽毒素 基因和促进疾病的产生。这些目标将为干预疾病提供基础， 开发小分子抑制剂。具体目标4。将SrrB和BrrB表征为组氨酸激酶， 磷酸化SrrA和BrrA的能力。具体目标5.为了评估SrrB/BrrB的小分子抑制剂， 防止SAgs、炭疽毒素和B的产生。炭疽菌胶囊目标6。为了确定三维结构 或细胞外/细胞内结构域，并与甲基萘醌或抑制剂组合。

Long-term goals are to understand the pathogenesis of methicillin-resistant Staphylococcus aureus (MRSA) that secrete superantigens (SAgs) such as enterotoxin (SE) B or C, SE-like Q, and toxic shock syndrome toxin-1 (TSST-1) and Bacillus anthracis. MRSA are emerging pathogens and their SAgs category B select agents. B. anthracis is a category A select agent. We have assembled two projects that are described below. Project 1. High-Affinity Molecules to Inhibit Superantigen Function. When produced in vivo or when purposely administered, SAgs are exceptionally toxic (TSS symptoms at doses of 0.1 ng/human). Most MRSA associated with post-influenza TSS, necrotizing pneumonia, and purpura fulminans produce SEB, SEC, SE-like Q, and TSST-1. Specific Aim 1. To engineer and characterize V(3-T cell receptor (TCR) regions that bind with high affinity to SAgs and neutralize them, most importantly SEB, SEC, SE-like Q, and TSST-1. Specific Aim 2. To engineer and characterize MHC II regions that bind with high affinity to SAgs and neutralize their activities. Specific Aim 3. To test the ability of soluble Vp-TCRs and MHC Ms to neutralize the activities of SAgs in vitro and in vivo in rabbits. Project. 2: Inhibitors of SrrA-SrrB and BrrA-BrrB Regulated Exotoxin Production. MRSA require oxygen for exotoxin production. This observation led to identification of a "Master Switch" two-component system required for oxygen control of exotoxin production in MRSA. This system, designated srrA-srrB, represses exotoxin production and virulence under conditions of low oxygen. Recently, a homolog in B. anthracis was described-BrrA-BrrB. BrrA-BrrB functions to induce anthrax toxin genes and facilitate disease production. The aims will provide a foundation for interfering with diseases by developing small molecule inhibitors. Specific Aim 4. To characterize SrrB and BrrB as histidine kinases with ability to phosphorylate SrrA and BrrA. Specific Aim 5. To evaluate small molecule inhibitors of SrrB/BrrB to prevent production of SAgs, anthrax toxin, and B. anthracis capsule. Aim 6. To determine the 3-D structures of SrrB and BrrB proteins or extracellular/intracellular domains and combined with menaquinone or inhibitors.