Several crystal forms of the Bacillus stearothermophilus 50 S ribosomal particles

Abstract
Well‐ordered three‐dimensional crystals of the large subunit of Bacillus stearothermophilus have been obtained. Electron micrographs of positively stained sections of these crystals revealed that the ribosomal particles are packed in several modes. Cell dimensions have been determined for 4 crystal forms. Representative electron micrographs, their optical diffraction patterns and their two‐dimensional images are shown.