Illustration of the Par system of the R1 plasmid of E. coli. This system consists of the proteins ParR and ParM and the parC site on the plasmid. After replication, ParR interacts with the parC sites of the plasmids to form a partitioning complex. ParM-ATP binds to this complex and forms a filament, which pushes the plasmids towards the poles. ATP is hydrolyzed and ParM-ADP depolymerizes, leaving the plasmids at opposite poles.