Dynamic organization: chromosome domains in Escherichia coli.

Bacteria are small and their chromosomes are several orders of magnitude longer than the cell size. The chromosome is consequently compacted into a structure known as the nucleoid. Zooming into the nucleoid of the model organism Escherichia coli reveals additional layers of organization: the chromosomal domains. These domains are much more than simple compaction devices. Essential cellular processes such as chromosome segregation, gene regulation and DNA replication are dependent on the domain organization of the chromosome. Here, we provide an overview of discoveries about micro- and macrodomains in E. coli and discuss potential routes to be taken in future research.