title: Macromolecular finestructure by dark field electron microscopy.
abstract: The potential of dark field electron microscopy for examining details of unstained unshadowed macromolecules has been studied. Images produced by scattered electrons show sufficient contrast and resolution to reveal the helical nature of short sections of DNA or the cleft containing the active site in ribonuclease. Spreads of transfer RNA were observed to contain many trifoliate structures.
mesh_terms: D001665:Binding Sites; D004247:DNA; D046911:Macromolecular Substances; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D012313:RNA; D012260:Ribonucleases
chemical_list: D046911:Macromolecular Substances; D012313:RNA; D004247:DNA; D012260:Ribonucleases