pSK1 is a plasmid from Staphylococcus aureus. This plasmid has a partition system determined by a single gene, par, previously known as orf245. This gene does not effect the plasmid copy number nor the grow rate (excluding its implication in a post-segregational killing system). A centromere-like binding sequence is present upstream of the par gene, and is composed of seven direct repeats and one inverted repeat.