Although parvulin has no homology with larger prolyl isomerases such as cyclophilin and FKBP, it does share structural features with subdomains of other proteins involved in preparing secreted proteins for export from the cell.
Despite lacking a relationship with larger prolyl isomerases such as cyclophilin and FKBP, parvulin shares structural elements with specific regions found in other proteins that are responsible for preparing secreted proteins for their exit from the cell.