IDENTIFICATION AND CHARACTERIZATION OF A BACTERIAL CHROMOSOME PARTITIONING SITE

We have identified a DNA site involved in chromosome partitioning in B . subtilis. This site was identified in vivo as the binding site for t he chromosome partitioning protein Spo0J, a member of the ParB family of partitioning proteins. Spo0J is a site-specific DNA-binding protein that recognizes a 16 bp sequence found in spo0J. Allowing two mismatc hes, this sequence occurs ten times in the entire B. subtilis chromoso me, all in the origin-proximal similar to 20%. Eight of the ten sequen ces are bound to Spo0J in vivo. The presence of a site on an otherwise unstable plasmid stabilized the plasmid in a Spo0J-dependent manner, demonstrating that this site, called parS, can function as a partition ing site. This site and Spo0J are conserved in a wide range of bacteri al species.