Figure 2

The effect of improvements in resolution on ribosome electron density maps. (a-c) Views of the entire surface of the large ribosomal subunit of H. marismortui that interacts with the small ribosomal subunit. (a) An EM reconstruction of that subunit that has a resolution of 20 Å. (b) An X-ray crystallographic image of the same particle, also at a resolution of 20 Å. (c) The same as (b) except for the resolution, which is 9 Å. All three images in (a-c) are from [9]. (d) A view of the face of the large subunit at a resolution of 5 Å, with the positions of L1 and L10 indicated in yellow [11]. (e) Electron density corresponding to a helix of 23S rRNA at a resolution of 5 Å [11]. (f) The electron density for a helix at a resolution of 2.4 Å [14].