MINORITY HIGH SCHOOL STUDENT RESEARCH APPRENTICE PROGRAM

我们建议购买蔡司 EM 902 透射电子 带有 Castaing 能量过滤器的显微镜，用于更换磨损的 JEOL JEM100B-3 一直满足人们的日常需求 生物物理学研究部和伟大的教授 密歇根大学湖泊研究部。 的 现有的显微镜在 1985 年的一半时间里无法使用， 导致至少一项研究项目中止，并且 场外其他项目的绩效。 新仪器将 用于可溶性蛋白质晶体的常规显微镜检查， DNA 和分离的海胆组蛋白基因染色质。 低剂量 葡萄糖包埋和冷冻水合周期的显微镜检查 膜结合蛋白阵列也在计划中。 高级 负染色和冷冻水合的显微镜检查 染色质将用于直接测试和精炼最近的 提出了染色体纤维内部结构的模型。 通过消除非弹性将实现更大的对比度 电子，它主导着冷冻分子的图像。 电子能谱成像将用于确定 染色质纤维中蛋白质和 DNA 的径向分布。 在 此外，还将开发非弹性暗视野显微镜 未染色生物分子的定量质量分析——a 独特的应用程序由两位拥有丰富经验的教师支持 有效地使用扫描透射电子显微镜 布鲁克海文国家实验室的设施，以确定 染色体纤维和酶内质量的分布。 该显微镜将位于生物物理研究中心 密歇根大学分部，这将确保其 将充分利用独特的能力进行生化、 分子水平的生物物理学和细胞生物学研究。

We propose to purchase a Zeiss EM 902 transmission electron microscope with Castaing energy filter, to replace a worn-out JEOL JEM100B-3 that has been serving the day-to-day needs of the faculty of the Biophysics Research Division and the Great Lakes Research Division of The University of Michigan. The existing microscope has been inoperable during half of 1985, causing discontinuation of at least one research project and the performance of other projects off-site. The new instrument will be used for routine microscopy of crystals of soluble proteins, DNA, and isolated sea urchine histone gene chromatin. Low dose microscopy of glucose-embedded and frozen-hydrated periodic arrays of membrane-bound proteins are also planned. Advanced microscopy of negatively-stained and of frozen-hydrated chromatin will be used to directly test and refine a recently proposed model for the internal structure of chromosome fibers. Greater contrast will be achieved by elimination of the inelastic electrons, which dominate the images of frozen molecules. Electron spectroscopic imaging will be used to determine the radial distribution of protein and DNA in chromatin fibers. In addition, inelastic dark field microscopy will be developed for quantitative mass analysis of unstained biological molecules -- a unique application supported by two faculty who have productively used the scanning transmission electron microscopy facilities at Brookhaven National Laboratory to determine the distribution of mass within chromosome fibers and enzymes. The microscope will be located in the Biophysics Research Division of The University of Michigan, which will assure that its unique capabilities will be fully exploited for biochemical, biophysical, and cell biological studies at the molecular level.