The development of molecular biology techniques - including the polymerase chain reaction (PCR) - has increased dramatically the rate at which new proteins are identified, characterized, sequenced, and expressed in milligram amounts. However, further progress in many of the systems created by these new technologies is being hampered by the lack of 3-D structural information. Multidimensional NMR methods have helped to release this bottleneck, but for many systems, especially those involving proteins of 18KD or larger, x-ray diffraction analysis is still the best technique available for atomic structure determination. Our Department is in the process of expanding and the addition of new faculty is placing excessive demand on our x-ray data collection equipment. We must therefor expand our data collection capabilities in order to provide adequate access to all members of our department. In this application we propose to purchase a new data collection system consisting of a rotating anode, an image plate system and a cooling device. This system, in addition to effectively doubling our present data collection throughput, will allow us to collect better high resolution data and to improve the accuracy of anomalous dispersion measurements.
