Two members of this family are found in Colwellia psychrerythraea (strain 34H / ATCC BAA-681) and one each in various other species of Colwellia and Shewanella. One member from C. psychrerythraea is of special interest because it is preceded by the same cis-regulatory site as a number of genes that have the PEP-CTERM domain described by PEP_anchor (IPR013424).