Members of this protein family are found so far in Methanohalophilus mahii DSM 5219 and Methanohalobium evestigatum Z-7303, along with five and nine proteins, respectively, with the VPXXXP-CTERM protein sorting signal (TIGR04143). In these species, this boutique system represents a second exosortase/archaeosortase-type system.
Jiyao W et al.(2023). "The conserved domain database in 2023.",