This entry identifies a family of proteins, around 100 amino acids in length, that include a predicted signal sequence and a perfectly conserved motif, RAQPRD, towards the C terminus. They are found in the Pseudomonas putida TOL plasmid pWW0 and in cryptic plasmid regions of Salmonella enterica subsp. enterica serovar Typhi and Pseudomonas syringae pv. tomato str. DC3000. The function of these proteins is unknown.