SAXS STUDIES OF THE BACTERIAL CELL WALL

细菌细胞壁的 SAXS 研究

• 批准号: 7722077
• 负责人: GRANT J JENSEN
• 金额: $ 0.06万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7722077
• 关键词: Anodes; Antibiotics; Bacteria; Cell Wall; Cells; Complement; Computer Retrieval of Information on Scientific Projects Database; Cytolysis; Data; Electrons; Funding; Grant; Institution; Mechanical Stress; Modeling; Osmotic Pressure; Range; Research; Research Personnel; Resources; Solutions; Source; Structure; Synchrotrons; Techniques; United States National Institutes of Health; research study; size

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The cell wall is a fundamental structure of the bacterial cell. This Gigadalton-sized macromolecular meshwork encases the entire cell and protects bacteria from mechanical stress. Indeed, antibiotics that interfere with cell wall synthesis or turnover cause the cell to lyse due to the high (ca. 3 atm.) internal osmotic pressure. Bacterial cell walls were examined by small angle solution x-ray scattering a few decades ago, but with much less bright sources (rotating anodes), and in a dehydrated state. These experiments suggested that bacterial cell walls are non-periodic. New data, however, suggest they are periodic. We are in the midst of trying to resolve the question by electron cryotomographic techniques, but wish to complement these studies with SAXS. We believe the powerful modern synchrotrons may reveal significantly more detail about short-range order than was obtained earlier, which would differentiate and refine the existing models of cell wall structure.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 细胞壁是细菌细胞的基本结构。这种千兆道尔顿大小的大分子网状结构包裹着整个细胞，保护细菌免受机械应力。事实上，干扰细胞壁合成或周转的抗生素会导致细胞由于高（约 3 个大气压）的内部渗透压而裂解。几十年前，人们通过小角度溶液 X 射线散射来检查细菌细胞壁，但光源的亮度要低得多（旋转阳极），并且处于脱水状态。这些实验表明细菌细胞壁是非周期性的。 然而，新数据表明它们是周期性的。我们正在尝试通过电子冷冻断层扫描技术解决这个问题，但希望用 SAXS 来补充这些研究。 我们相信，强大的现代同步加速器可能会比以前获得的更多关于短程有序的细节，这将区分和完善现有的细胞壁结构模型。