THREE DIMENSIONAL RECONSTRUCTIONS OF ARCHAEA

古细菌的三维重建

• 批准号: 7722829
• 负责人: NORMAN R PACE
• 金额: $ 2.76万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7722829
• 关键词: Archaea; Bacteria; Biochemical; Biological; Biological Preservation; Cells; Computer Retrieval of Information on Scientific Projects Database; Culture Media; DNA; DNA Probes; Eukaryota; Eukaryotic Cell; Exclusion; Ficoll; Freeze Substitution; Freezing; Funding; Genetic Transcription; Glucose; Grant; Institution; Knowledge; Methods; Modeling; Molecular; Morphology; Nature; Nuclear; Organism; Phylogenetic Analysis; Polymers; Process; Prokaryotic Cells; Rate; Research; Research Personnel; Resources; Ribosomes; Salmonella; Source; Structure; Sucrose; Sulfolobus; Sulfolobus solfataricus; Tomogram; Translations; Trees; United States National Institutes of Health; Work; cellular imaging; instrumentation; pressure; rapid technique; reconstruction; tomography

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 phylogenetic tree of all known organisms comprises three distinct branches: Eucarya, Bacteria and Archaea. The Archaeal branch was only recently recognized as a coherent group that is phylogenetically distinct from Bacteria. Our knowledge of the fine structure of prokaryotic cells (Archaea and Bacteria) is significantly less than what we know about their biochemical and molecular organization. This is due primarily to limitations in preservation methods and, to some extent, in instrumentation. Advances in modern techniques of rapid freezing and freeze-substitution have overcome some of these problems, yielding elegant preservation of some prokaryotic organisms. Since molecular studies suggest that Archaea have more in common with Eukaryotes than with Bacteria, in terms of transcription, translation and other DNA related processing mechanisms, the morphology of these organisms may yield a wealth of biological information. Whole cell images of high-pressure frozen, freeze-substituted Sulfolobus solfataricus have been captured via serial section tomography. As a control, whole cell images of the bacterium Salmonella have been prepared in an identical manner. The whole cell tomograms have allowed the enumeration of several different structures in Sulfolobus, at least one of which varies according to the presence or absence of glucose in the medium in which the cells are grown. DNA preservation, previously a problem, is currently quite good with the addition of the sucrose polymer Ficoll-70 to the growth medium just prior to freezing. Lowicryl embedded Sulfolobus has been successfully probed for DNA and verified by tomographic ribosome exclusion models. Work will continue on the characterization of nuclear body structure of Sulfolobus and Salmonella during the next year. The principal rate determining step going forward is the labor intensive nature of segmentation.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 所有已知生物的系统发育树都包括三个不同的分支：欧洲，细菌和古细菌。 古细菌分支最近才被公认为是一个连贯的组，在系统发育上与细菌不同。 我们对原核细胞（古细菌和细菌）的精细结构的了解明显少于我们对它们的生化和分子组织的了解。 这主要是由于保存方法的局限性，并且在某种程度上是仪器的限制。 快速冷冻和冻结固定的现代技术的进步已经克服了其中的一些问题，从而优雅地保存了一些原核生物。 由于分子研究表明，在转录，翻译和其他与DNA相关的处理机制方面，古细菌与真核生物相比与细菌有更多的共同点，因此这些生物的形态可能会产生大量的生物学信息。 高压冷冻，冻结取代的Sulfolobus solfataricus的全细胞图像已通过串行部分断层扫描捕获。 作为对照，沙门氏菌细菌的全细胞图像已经以相同的方式制备。 整个细胞断层图允许在磺胺虫中列举几种不同的结构，其中至少一个根据细胞生长的培养基中的存在或不存在葡萄糖而变化。 DNA保存（以前是一个问题）目前非常好，在冷冻之前将蔗糖聚合物FICOLL-70添加到生长培养基中。 Lowicryl嵌入的磺胺可用于DNA，并通过断层核糖体排除模型进行了验证。 第二年，将继续进行磺胺bus和沙门氏菌核体结构的表征。 确定进步的主要利率是分割的劳动密集型性质。