Analytical Ultracentrifuge for Biochemical Studies

我们要求购买贝克曼XL-A型分析超精密仪器。该仪器是一种最先进的超级仪器，沿着由领先的研究专家制定的指导方针。虽然只有三年的历史，但这一工具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处提到它的使用。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工具。 过去几乎放弃这种方法是由于几个因素，但旧的E型仪器在维护和使用方面的困难本身就是充分的原因。 确实，在许多情况下，现在存在用于测定蛋白质分子量的准确的替代方法，例如，DNA测序和质谱分析。然而，分析超离心（AUC）在其多功能性方面表现出色，可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在许多情况下用于分析复杂缔合大分子的优越性。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，不像二级方法需要标准品，并且假设这些标准品的行为与所研究的分子相同。此外，AUC可以提供流体动力学参数，从中可以估计大分子的形状。这种新的AUC仪器的另一个重要优点是，它与用于控制和分析实验的计算机程序兼容，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使用强大的计算密集型方法来分析非常复杂的大分子系统，并且相对容易，只需少量的培训和练习。这些程序不断得到改进，可通过互联网用户群组访问，该群组还允许用户访问该领域的所有领导者。 本申请的PI（HOS）具有近20年使用E型分析超浓凝胶和相关方法研究简单和复杂缔合体系的经验。他在数据分析的计算机方法方面拥有更丰富的经验-这些方法在分析新AUC仪器的数据时特别有价值。 本申请中描述的项目广泛依赖于所要求的AUC仪器的特殊优势。例如，大多数研究涉及大分子缔合。通常，两种（或更多）方法可以提供比单独使用任何一种方法更好的见解。AUC的情况也是如此，如下面关于多糖结构的项目所示。在这里，特性粘度和沉降速度数据的组合提供了独立于分子水合作用的分子形状的信息。 幸运的是，我们有最先进的粘度计和其他现代方法来补充AUC。总之，下面描述的项目处于基础研究的前沿，将大大加强，在某些情况下，严重依赖于，分析超浓缩。 该方法具有显著的通用性，并且所寻求的当前仪器在技术和易用性方面提供了显著的进步。 目前没有处于OK状态的功能性AUC仪器。然而，在相对较短的时间内，我们已经确定了一批令人印象深刻的科学家（约25人），他们表达了对XL-A的强烈愿望和重要需求。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，因为他们熟悉了它的功能和他们的研究发展。 由于其在分子生物学和高分子化学中的核心价值及其在未来的预期流行， 实验室，重要的是，我们的学生熟悉这种仪器和方法。我们有积极的研究活动，为本科生通过研究生。此外，我们最近获得了两项为少数民族服务的主要赠款：霍华德休斯赠款，"本科生物科学教育计划"，100万美元。在接下来的4年里，和一个国家科学基金会的赠款，"俄克拉荷马州少数民族参与科学的国家联盟"在未来5年内为500万美元。这两项补助金都是由生物化学和分子生物学系获得和管理的。在获得该仪器后，这些计划支持的许多学生将有机会接受这项杰出技术的培训。

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.