Getting organized--how bacterial cells move proteins and DNA.

In recent years, the subcellular organization of prokaryotic cells has become a focal point of interest in microbiology. Bacteria have evolved several different mechanisms to target protein complexes, membrane vesicles and DNA to specific positions within the cell. This versatility allows bacteria to establish the complex temporal and spatial regulatory networks that couple morphological and physiological differentiation with cell-cycle progression. In addition to stationary localization factors, dynamic cytoskeletal structures also have a fundamental role in many of these processes. In this Review, we summarize the current knowledge on localization mechanisms in bacteria, with an emphasis on the role of polymeric protein assemblies in the directed movement and positioning of macromolecular complexes.