Biomacromolecular localization in bacterial cells by the diffusion and capture mechanism

Subcellular localization of biomacromolecules (nucleotides and proteins) is the base for their proper function in bacterial cells. One model to explain the localization of biomacromolecules, particularly proteins, is "diffusion and capture". In this model, proteins are localized by diffusion through the cytoplasm or the membrane until binding to another protein or proteins that were already previously sequestered in cells. The use of fusions with fluorescent proteins to follow the fate of biomacromolecules has given new insight into the molecular localization mechanisms in living cells. Here, several proteins following a diffusion and capture mechanism to reach their proper location in the cells are presented. Some RNAs also seem to localize by this mechanism. It is an intrinsic feature that the information for molecular localization should exist in the sequences of protein itself. However, very little information has been available in this field to date.