Analytical Ultracentrifuge for Biochemical Studies

我们要求购买贝克曼XL-A型分析超离心机。该仪器是一种最先进的超离心机，由领先的研究专家制定指导方针。虽然这台仪器问世还不到三年，但它在该领域产生了令人印象深刻的影响，在最近的参考书目中有近100处引用了它的使用。很明显，在不久的将来，几乎所有从事结构-功能研究的生物学研究人员都将把这种方法纳入他们的研究范围。其他地方没有生产类似的仪器。过去几乎放弃这种方法是由于几个因素，但旧型号E仪器的维护和使用困难本身就是充分的原因。的确，在许多情况下，现在存在精确的替代方法来测定蛋白质的分子量，例如DNA测序和质谱法。然而，分析性超离心（AUC）的优点在于其通用性，以适应广泛的实验条件和不同类型的大分子。也许最重要的是AUC在分析复杂缔合大分子的许多情况下的优越性。AUC的另一个优点是它基于严格的模型方程，是一种主要方法，不像次要方法需要标准，并且假设这些标准与所研究的分子具有相同的行为方式。此外，AUC可以提供水动力参数，从中可以估计大分子的形状。这种新型AUC仪器的另一个重要优点是它与计算机程序兼容，用于控制和分析实验，使其在用户友好性方面取得了非凡的进步。现在，即使是非专家也可以相对容易地利用强大的计算密集型方法分析非常复杂的大分子系统，只需要少量的训练和建议。这些程序不断得到改进，可以通过互联网用户组获得，用户也可以访问该领域的所有领导者。本应用程序的PI （HOS）有近20年的经验，使用E型分析超离心机和相关方法研究简单和复杂的伴生系统。他在数据分析的计算机方法方面有更广泛的经验，这些方法在分析新的AUC仪器的数据时特别有价值。本应用程序中描述的项目在很大程度上取决于所要求的AUC仪器的特殊优势。例如，大多数研究都与大分子的关联有关。通常情况下，两种（或更多）方法比单独使用任何一种方法都能提供更深刻的见解。下面的多糖结构项目也说明了AUC的情况。在这里，特性粘度和沉降速度数据的结合提供了与分子水合作用无关的分子形状信息。幸运的是，我们有顶级的粘度测定法和其他与AUC互补的现代方法。总之，下面所描述的项目处于基础研究的前沿，并将大大加强，在某些情况下，严重依赖于分析性超离心。这种方法具有显著的通用性，目前所寻求的仪器在技术和易用性方面提供了突出的进步。目前OK州没有功能AUC仪器。然而，在相对较短的时间内，我们在OK找到了一批令人印象深刻的科学家（大约25人），他们对xml - a表达了强烈的愿望和重要的需求。此外，OK的许多其他人无疑会发现该仪器对他们的研究非常有帮助，因为他们熟悉它的功能和他们的研究发展。由于它在分子生物学和聚合物化学中的核心价值以及它在未来实验室中的预期流行，我们的学生熟悉这种仪器和方法是很重要的。我们对本科生和研究生都有积极的研究活动。此外，我们最近还获得了两项为少数族裔服务的主要资助：一项为“本科生生物科学教育项目”的霍华德·休斯资助，金额为100万美元。并在未来5年内获得美国国家科学基金会“俄克拉荷马州少数民族参与科学联盟”500万美元的资助。这两项资助都是由生物化学和分子生物学学院获得和管理的。在获得该仪器后，由这些项目支持的众多学生将有机会接受这一杰出技术的培训。

We are requesting the acquisition of the Beckman model XL-A analytical ultracentrifuge. This instrument is a state-of-the-art ultracentrifuge built along guidelines developed by the leading research experts. Though scarcely three years old, this instrument has made an impressive impact in the field with nearly 100 references to its use in a recent bibliography. It is clear that virtually all biological researchers pursuing structure-function studies will include this method in their repertoire in the near future. No comparable instrument is manufactured elsewhere. The past near abandonment of this approach is due to several factors, but the difficulties in maintenance and use of the old model E instrument are sufficient reasons by themselves. It is true that accurate alternative methods now exist in many cases for determining molecular weights of proteins, e.g., DNA sequencing and mass spectrometry. However, analytical ultracentrifugation (AUC) excels in its versatility to accommodate a wide range of experimental conditions and different types of macromolecules. Perhaps most important is the superiority of AUC in many cases for analyzing complex associating macromolecules. Another advantage of AUC is that it is based on rigorous model equations and is a primary method unlike secondary methods that require standards and the assumption that these standards behave in the same manner as the molecule being studied. In addition, AUC can provide hydrodynamic parameters from which shapes of macromolecules can be estimated. Another important advantage of this new AUC instrument is that it is compatible with computer programs for controlling and analyzing experiments giving it an extraordinary advance in user-friendliness. Now even non-experts can analyze very complex macromolecular systems utilizing powerful calculation-intensive methods with relative ease and a modest amount of training and advisement. These programs continually being improved, are available through th e internet users groups that also allows users to access all leaders in this field. The PI (HOS) of this application has nearly 20 years of experience using the model E analytical ultracentrifuge and related methods for studying simple and complex associating systems. He has even more extensive experience in computer methods of data analysis - methods that are especially valuable in analyzing data from the new AUC instrument. The projects described in this application depend extensively on the special advantages of the requested AUC instrument. For example, the majority of the studies are concerned with macromolecular associations. It is often true that two (or more) methods can provide greater insights than either method alone. Such is the case with AUC also as illustrated in the project below on polysaccharide structures. Here the combination of intrinsic viscosity and sedimentation velocity data provide information on molecular shape that is independent of the molecular hydration. Fortunately, we have top-of-the line viscometry and other modern methods that are complementary to AUC. In summary, the projects described below are at the forefront of basic research and will be greatly enhanced by, and in some case critically dependent on, analytical ultracentrifugation. This method has remarkable versatility and the current instrument sought provides outstanding advances in technology and ease of use. Currently there is no functional AUC instrument in the State of OK. However, in ~ relatively short time we have identified an impressive array of scientists in OK (about 25) who have expressed both a keen desire and an important need for the XL-A. In addition, many others in OK will undoubtedly find the instrument extremely helpful to their research as they become familiar with its capabilities and their research develops. Because of its central value in molecular biology and polymer chemistry and its expected prevalence in future labs, it is important that our students become familiar with this instrument and method. We have vigorous research activities for both undergraduate through postgraduate students. In addition, we have recently obtained two major grants serving minorities: a Howard Hughes grant, "Undergraduate Biological Sciences Education Program," of $1,000 000. over the next 4 years, and an NSF grant, "Oklahoma State Alliance for Minority Participation in Science" for $5,000,000 over the next 5 years. Both of these grants were obtained and are administered by faculty in Biochemistry and Molecular Biology. Upon acquisition of the instrument, numerous students supported by these programs will have the opportunity to become trained in this eminent technology.