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.
