HIGH-RESOLUTION CRYSTALS AND PRELIMINARY-X-RAY DIFFRACTION STUDIES OFA CATALYTIC RNA

High-resolution single crystals of a catalytic RNA molecule derived fr om the sequence of the satellite RNA of tobacco ringspot virus have be en obtained. The unit-cell volumes of the RNA crystals vary depending on the crystallization conditions and temperature. The best crystal fo rm, when flash frozen, has space group P1 with unit-cell dimensions a = 53.08, b = 71.81, c = 28.03 angstrom, alpha = 98.43, beta = 104.32 a nd gamma = 74.540. This form diffracts to a resolution of 2.4 angstrom . A heavy-atom derivative search is in progress.