Simple they may be, but bacteria have much to teach us. As an experimental model they are easily manipulated, allowing complex processes to be dissected and providing clues to the mechanisms responsible for these events in higher organisms.

Take structural analyses of the large and small ribosomal subunits, for instance, where bacteria have paved the way as the study system of choice. In their review on page 514, Denis Lafontaine and David Tollervey chart progress in this field — from initial structural studies in thermophilic bacteria to the latest work on the mechanisms behind ribosomal synthesis, translocation and catalysis.

But bacteria are more than simplified versions of eukaryotic cells — they have developed systems to address their own specific needs. One example is the movement of DNA within and between bacterial cells, a process required for fundamental events such as chromosome segregation and gene transfer. On page 538, Jeff Errington and colleagues describe how the identification of molecules responsible for this transfer is revealing the basis of other processes unique to bacteria.

Another specialized system involves the array of toxins that are produced by bacteria to disrupt the functioning of their eukaryotic hosts. The functions of these toxins vary; whereas some can punch holes in the plasma membrane, others work by interfering with cell signalling. But as Giampietro Schiavo and Gisou van der Goot discuss on page 530, researchers are increasingly harnessing these weapons to explore cellular processes. And the Highlight on page 488 follows this theme, describing how it might be possible to prevent bacterial infection by exploiting another bacterial talent — their ability to distinguish between high and low population density.