It is proposed that an Optronics C-4100SP microdensitometer, and a Silicon Graphics Iris 4D/280SX computer be purchased, for use in structural studies of proteins and nucleic acids by Drs. Stubbs, Anders, Flicker, Robinson, Newcomer and others. Drs. Flicker and Robinson plan to utilize cryo-electron microscopy in their structural studies of protein assemblies: Dr. Flicker is studying actomyosin complexes; Dr. Robinson studies neurotoxins. Dr. Stubbs' studies of plant virus structure will also benefit from cryo-electron microscopy facilities. Drs. Anderson, Newcomer, and Stubbs are using protein crystallographic methods to study a variety of molecules. With a number of new crystals new available, the present facilities have reached saturation. Furthermore, several of the crystal forms have unit cells too large to permit data collection using existing facilities. Dr. Stubbs' fiber diffraction studies also require equipment capable of resolving diffraction data from very large unit cells. The major users make heavy use of the existing computer facilities. Structural refinement, especially by Dr. Anderson and Stubbs and new projects of Dr. Newcomer and Flicker, will require substantially increased computing capacity.
