Arrest of bacterial DNA replication

The chromosomes of both gram-positive and gram-negative bacteria contain sites that arrest the progression of DNA replication forks. These replication-arrest sites limit the end of the replication cycle to a particular region of the chromosome, called the terminus region. Replication arrest is mediated by protein-DNA complexes that show polarity of function: they arrest DNA replication from one direction only. This paper reviews our current knowledge of the replication-arrest complexes of Bacillus subtilis and Escherichia coli and examines possibilities for the function and mechanism of action of these complexes within the bacterial cell.