Deepening ribosomal insights.

The remarkable progress of cryo-electron microscopy and crystallography in elucidating ribosomal structure and function continues. Most recently, two papers about complete 70S ribosomes from Thermus thermophilus at 2.8- and 3.7-A resolution give us more details about the conformations of bound transfer RNA (tRNA) molecules; the bridges between subunits; the locations and roles of proteins, magnesium ions, and water molecules; and the dynamics of ribosomes. Very significant new insights have been gained, particularly for the tRNAs, which can only be studied in their entirety in full ribosomes.