BOTULINUM NEUROTOXIN SEROTYPE B INHIBITOR DESIGN

B 型肉毒神经毒素抑制剂设计

• 批准号: 8363349
• 负责人: Karen A Allen
• 金额: $ 0.31万
• 依托单位: BROOKHAVEN SCIENCE ASSOC-BROOKHAVEN LAB
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8363349
• 关键词: Active Sites; Adverse effects; Algorithms; Attention; Bacteria; Binding; Binding Sites; Bontoxilysin; Bypass; Catalytic Domain; Chemicals; Clostridium botulinum; Cobra; Communities; Cosmetics; Crystallization; Crystallography; Electrostatics; Family; Food Poisoning; Funding; Goals; Grant; Human; Knowledge; Length; Ligands; Light; Medical; Membrane Proteins; Molecular Models; National Center for Research Resources; Nature; Organic solvent product; Principal Investigator; Property; Research; Research Infrastructure; Resources; Ricin; Serotyping; Site; Solvents; Source; Specificity; Structure; Synchrotrons; Tetanus; Toxin; United States National Institutes of Health; botulinum toxin type B; chemical group; cost; crosslink; design; holotoxins; improved; inhibitor/antagonist; macromolecule; man; molecular modeling; protein structure; scaffold; tool

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The seven botulinum neurotoxins (BoNTs) originate from the Clostridium botulinum species of bacteria and are, without exception, the most potent toxins known to man- bypassing tetanus, cobra, and ricin toxins in their lethal nature. The contexts in which humans may encounter toxins are many and include bioterrorist attacks, cosmetic and non-cosmetic medical applications, and food poisoning. Indeed, the B serotype (BoNT/B), while not at the forefront of the scientific community's attention heretofore, has been shown to be responsible for a significant portion of annual food poisoning cases caused by this family of toxins. Given the similarities in protein structure between BoNT serotypes and their common catalytic mechanisms, it is not unreasonable to suppose that BoNT/B may also be used as part of a large-scale attack. Ultimately, the goal of our studies is to synthesize efficacious BoNT/B inhibitors that are as exquisitely specific to the toxin as possible so as to avoid nonspecific interactions with other macromolecules in the body and hence unanticipated side effects. To this end, we hope to gain knowledge of the biophysical interactions between ligands pre-screened for optimal activity and the active site of the BoNT/B light chain (BLC), the catalytic subunit of the holotoxin. Applying x-ray diffraction and molecular modeling tools to a truncated form of the BLC (tBLC) will attain this; the full-length construct has proven difficult to crystallize. While we have attained the first tBLC crystals, refinement of the crystallization conditions is required to improve their quality and is something we deem feasible by mid April.Additionally, we would ideally like to optimize existing candidate scaffold(s) and/or develop them de novo. To achieve this goal, the Multiple Solvent Crystal Structures (MSCS) empirical algorithm will be employed to identify exo-sites on the protein surface by examining the localization of organic solvents with distinct chemical functionalities in chemically cross linked crystals. This will help improve specificity of inhibitor binding by exploring binding sites external to the catalytic site that may be specific for chemical groups with defined electrostatic or steric properties. This approach, depending on how tBLC crystallization refinement progresses, might also be possible to pursue during RapiData.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 这七种肉毒杆菌神经毒素（BoNT）源自肉毒梭菌属的细菌，并且无一例外地是已知对人类最有效的毒素-在其致命性质上绕过破伤风、眼镜蛇和蓖麻毒素。 人类可能遇到毒素的情况有很多，包括生物恐怖袭击，化妆品和非化妆品医疗应用以及食物中毒。事实上，B血清型（BoNT/B）虽然迄今为止未处于科学界关注的最前沿，但已被证明是由该毒素家族引起的年度食物中毒病例的显著部分的原因。 鉴于BoNT血清型之间蛋白质结构的相似性及其共同的催化机制，推测BoNT/B也可能被用作大规模攻击的一部分并非不合理。 最终，我们研究的目标是合成有效的BoNT/B抑制剂，其尽可能精确地特异于毒素，以避免与体内其他大分子的非特异性相互作用，从而避免意外的副作用。 为此，我们希望获得知识的生物物理之间的相互作用的配体预筛选的最佳活性和活性位点的BoNT/B轻链（BLC），全毒素的催化亚基。 将X射线衍射和分子建模工具应用于截短形式的BLC（tBLC）将实现这一点;全长结构已被证明难以结晶。 虽然我们已经获得了第一个tBLC晶体，但需要改进结晶条件以提高其质量，我们认为在4月中旬之前是可行的。此外，我们希望优化现有的候选支架和/或重新开发它们。 为了实现这一目标，将采用多溶剂晶体结构（MSCS）经验算法，通过检查化学交联晶体中具有不同化学功能的有机溶剂的定位来识别蛋白质表面上的外位点。 这将有助于通过探索催化位点外部的结合位点来改善抑制剂结合的特异性，所述催化位点可能对具有限定的静电或空间性质的化学基团具有特异性。 这种方法，取决于tBLC结晶细化的进展，也可能在RapiData期间进行。