This family includes proteins which are essential for plasmid replication [1] and plasmid DNA relaxation [2].

1: Complete nucleotide sequence and characterization of pUA140, a cryptic plasmid from Streptococcus mutans. Zou X, Caufield PW, Li Y, Qi F; Plasmid. 2001;46:77-85. PMID:11591133

2: Two atypical mobilization proteins are involved in plasmid CloDF13 relaxation. Nunez B, De La Cruz F; Mol Microbiol. 2001;39:1088-1099. PMID:11251827