Acquisition of NMR and X-ray Instrumentation for Structural Biology

使用核磁共振光谱和X射线结晶学的结构生物学和生物物理学是哥伦比亚大学历史上的强项。研究兴趣从新技术的发展，到蛋白质和核酸的结构和动力学性质的确定，再到基于结构的生物大分子基本生物物理和化学性质的研究。哥伦比亚大学对结构生物学和生物物理学的开创性贡献的未来延续和扩大，受到现有核磁共振和X射线仪器日益老化和不足的威胁。核磁共振中心目前拥有三台布鲁克核磁共振光谱仪，质子共振频率分别为300兆赫、400兆赫和500兆赫。光谱仪安装于1985年；自最初安装以来，只有500 MHz仪器进行了重大升级。核磁共振光谱仪的年龄限制了至关重要的现代实验的性能。生物化学和分子生物物理系的X射线设施包括两个Rigaku RU-200旋转阳极X射线发生器、两个Huber进动相机、一个Rigaku RAXIS-II成像区探测器、一个由Rigaku AFC-6测角仪提供服务的Xong-Hamlin多线面探测器和三个低温系统。Xong-Hamlin多丝探测器不再适用于当前的研究项目。对于核磁共振和x射线设备，安排关键实验的积压工作对于当前用户来说从一到两个月不等。为了满足明显的需求，将购买一台新的600 MHz核磁共振光谱仪，并将为500 MHz和400 M-HZ仪器购买控制台升级。这些决定基于以下考虑：(1)有必要增加一台高场光谱仪，为现有教员的(新兴)研究小组提供及时访问，并有可能额外招聘一到两名初级教员。(2)为了进行最先进的实验，需要升级500 MHz的控制台。(3)400兆赫光谱仪的升级将允许开发方法、初步收集数据以评估样品的完整性，并在较低的磁场下进行培训。这将大大提高500兆赫和600兆赫光谱仪的产量。为了缓解目前X射线晶体仪器的局限性，将购买两个成像板面积探测器系统(包括探测器、聚焦镜和低温输送系统)和一台Rigaku RU-200旋转式阳极X射线发生器。在所要求的收购之后，x射线设施将容纳三个x射线发生器、三个面探测器系统和两个Huber进动相机。每个X射线发生器可以支持两个进动相机或面积探测器；因此，其中两个X射线发生器将配备一个进动相机和一个面积探测器。第三台发电机将配备面积探测器，留出一个插槽供未来扩展。徐哈姆林探测器将被退役。所要求的仪器将带来以下优势：(I)X射线设备的能力大约翻一番，将允许现有的研究小组及时进行实验；(2)由于有足够的X射线仪器来支持另一个新的教员研究小组，将有助于招募生物分子X射线结晶学的额外教员；以及(3)新探测器(和光学)的提高的灵敏度将使以前在同步加速器源进行的实验能够在内部进行。

Structural biology and biophysics using NMR spectroscopy and x-ray crystallography are historic strengths of Columbia University. Research interests range from the development of new techniques, to the determination of the structural and dynamical properties of proteins and nucleic acids, to the structure-based investigation of fundamental biophysical and chemical properties of biological macromolecules. Future continuation and expansion of Columbia University's seminal contributions to structural biology and biophysics is threatened by the increasing age and inadequacy of the existing NMR and x-ray instrumentation. The NMR Center presently houses three Bruker NMR spectrometers with proton resonance frequencies of 300 MHz, 400 MHz and 500 MHz. The spectrometers were installed in 1985; only the 500 MHz instrument has been upgraded to any significant extent since the original installation. The age of the NMR spectrometers precludes performance of critically important modern experiments. The Department of Biochemistry and Molecular Biophysics x-ray facility houses two Rigaku RU-200 rotating anode x-ray generators, two Huber precession cameras, one Rigaku RAXIS-II imaging area detector, one Xuong-Hamlin multiwire area detector served by a Rigaku AFC-6 goniormeter, and three cryogenic systems. The Xuong-Hamlin multiwire detector is no longer suitable for current research projects. For both the NMR and x-ray facilities, backlogs for scheduling critical experiments ranges from one to two months with current users. To address evident needs, a new 600 MHz NMR spectrometer will be purchased and consoles upgrades will be purchased for the 500 MHz and 400 M-Hz instruments .These decisions are based on the following considerations: (1) an additional high field spectrometer is necessary to provide timely access for the (burgeoning) research groups of the present faculty and to make possible recruitment of one or two additional junior faculty members. (2) An upgr ade of the 500 MHz console is required for performance of state-of-the-art experiments. (3) An upgrade of the 400 MHz spectrometer will allow methods development, preliminary data collection to evaluate sample integrity, and training to be performed at lower field. This will have the effect of significantly leveraging production on the 500 MHz and 600 MHz spectrometers. To alleviate the limitations of the present x-ray crystallographic instrumentation, two imaging plate area detectors systems (including detector, focusing mirrors and cryo delivery system) and one Rigaku RU-200 rotating anode x-ray generator will be purchased. Following the requested acquisitions, the x-ray facility will house three x-ray generators, three area detector systems, and two Huber precession cameras. Each x-ray generator can support two precession cameras or area detectors; therefore, two of the x-ray generators will be equipped with a precession camera and an area detector. The third generator will be equipped with an area detector, leaving one slot for future expansion. The Xuong-Hamlin detector will be decommissioned. The following advantages will accrue from the requested instrumentation: (I) the approximate doubling of the capacity of the x-ray facility will permit existing research groups to perform experiments in a timely fashion; (2) recruitment of an additional faculty member in biomolecular x-ray crystallography will be facilitated by the availability of sufficient x-ray instrumentation to support another beginning faculty research group; and (3) the increased sensitivity of the new detectors (and optics) will permit performance "in-house" of experiments that previously have been performed at synchrotron sources.