HIGH PRESSURE CRYOCOOLING FOR BIOLOGICAL X-RAY DIFFRACTION MICROSCOPY

用于生物 X 射线衍射显微镜的高压低温冷却

• 批准号: 8363562
• 负责人: ENJU LIMA
• 金额: $ 0.52万
• 依托单位: CORNELL UNIVERSITY
• 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/8363562
• 关键词: Algorithms; Biological; Cellular Structures; Collaborations; Freezing; Funding; Goals; Grant; Ice; Image; Microscopy; Molecular; National Center for Research Resources; Noise; Phase; Principal Investigator; Problem Solving; Reporting; Research; Research Infrastructure; Resolution; Resources; Sampling; Solutions; Source; Staging; Testing; United States National Institutes of Health; X ray diffraction analysis; X-Ray Diffraction; cost; cryogenics; improved; pressure; prevent

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. We have developed cryogenic x-ray diffraction microscopy (cryo-XDM) for imaging hydrated, unstained biological samples and recently reported the first frozen-hydrated images of D. radiodurans with 8 keV x-rays at a resolution of 30 to 50 nm. Having shown the feasability of cryo-XDM in biological imaging, we hope to improve the resolution toward 10 nm to visualize fine cellular structures, possibly at the molecular level. So far, one of the main challenges in reaching this goal has been the ice condition. During the plunge-freezing stage, samples can become contaminated with crystalline ice which can result in increased noise levels preventing the phasing algorithm from finding a solution. To solve this problem we plan to utilize high-pressure freezing samples to preserve them in the amorphous ice state in collaboration with Dr. S. Gruner and Dr. C.U. Kim at Cornell. We request 1 day beamtime to test the feasibility of applying high-pressure freezing for biological XDM.

该副本是利用资源的众多研究子项目之一 由NIH/NCRR资助的中心赠款提供。对该子弹的主要支持 而且，副投影的主要研究员可能是其他来源提供的 包括其他NIH来源。 列出的总费用可能 代表subproject使用的中心基础架构的估计量， NCRR赠款不直接向子弹或副本人员提供的直接资金。 我们已经开发了用于成像水合的未染色生物样品的低温X射线衍射显微镜（Cryo-XDM），最近报道了以30至50 nm的分辨率为8 keV X射线的第一个冷冻放射性杜鹃的冷冻水分图像。在显示了冷冻XDM在生物成像中的可行性之后，我们希望改善向10 nm的分辨率，以可视化细胞结构，可能在分子水平上。到目前为止，达到这一目标的主要挑战之一是冰条件。在暴跌阶段，样品可以被结晶冰污染，从而导致噪声水平升高，从而阻止定相算法找到溶液。为了解决这个问题，我们计划利用高压冻结样品与S. Gruner博士和C.U. C.U.金在康奈尔。我们要求1天的束缚时间测试用于生物XDM的高压冻结的可行性。