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)和炭疽芽孢杆菌。耐甲氧西林金黄色葡萄球菌是新出现的病原体，其下垂B类精选 探员们。炭疽杆菌是一种A类选择剂。我们已经组装了两个项目，如下所述。 项目1.抑制超抗原功能的高亲和力分子。当在体内生产时或当 故意给药的SAG具有特别的毒性(TSS症状剂量为0.1毫微克/人)。多数 与流感后TSS、坏死性肺炎和暴发性紫癜相关的MRSA产生SEB， SEC、类似SE的Q和TSST-1。具体目的1.设计并鉴定V(3-T细胞受体，TCR)区 与SAG有高亲和力的结合并中和它们，最重要的是SEB、SEC、SE样Q和TSST-1。 具体目标2.设计和鉴定与SAGS和SAGS高亲和力结合的MHC II区域 中和他们的活动。具体目的3.检测可溶性VP-TCRs和MHC-ms的中和能力 SAGS的体内外活性。项目。2：受调节的SrrA-SrrB和BRRA-brrb抑制物 外毒素生产。耐甲氧西林金黄色葡萄球菌需要氧气来产生外毒素。这一观察结果导致了一种 耐甲氧西林金黄色葡萄球菌外毒素生产氧气控制所需的“总开关”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，在炭疽杆菌中发现了一个同源基因--bra-brrb。BRRA-brrb诱导炭疽毒素的功能 基因，并促进疾病的产生。AIMS将为通过以下方式干预疾病提供基础 开发小分子抑制剂。特指目的4.鉴定SrrB和Brrb为组氨酸激酶 使srA和brra磷酸化的能力。具体目的5.SrrB/brrb小分子抑制剂的评价 防止产生下垂、炭疽毒素和炭疽杆菌胶囊。目的6.确定三维结构 结合Srrb和brrb蛋白或胞外/胞内结构域，并与孟喹酮或抑制剂结合。

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.