DciA secures bidirectional replication initiation in Vibrio cholerae.

Replication is initiated bidirectionally in the three domains of life by the assembly of two replication forks at an origin of replication. This is made possible by the recruitment of two replicative helicases to a nucleoprotein platform built at the origin of replication with the initiator protein. The reason why replication is initiated bidirectionally has never been experimentally addressed due to the lack of a suitable biological system.

Plesiomonas shigelloides, an Atypical Enterobacterales with a Vibrio-Related Secondary Chromosome.

About 10% of bacteria have a multichromosome genome with a primary replicon of bacterial origin, called the chromosome, and other replicons of plasmid origin, the chromids. Studies on multichromosome bacteria revealed potential points of coordination between the replication/segregation of chromids and the progression of the cell cycle. For example, replication of the chromid of Vibrionales (called Chr2) is initiated upon duplication of a sequence carried by the primary chromosome (called Chr1), in such a way that replication of both replicons is completed synchronously.