| AD families | AD genes | Defense system | CLAN ID | Phages/MGEs | References | Description |
|---|---|---|---|---|---|---|
| APIS031 | DarA | restriction-modification (RM) | CLAN028 | P1 of E. coli | PMID:3029954 | Bind to phage DNA, thereby masking type I R–M recognition sites and preventing degradation of phage DNA. |
| APIS081 | CLAN028 | |||||
| APIS124 | CLAN028 | |||||
| APIS135 | CLAN028 | |||||
| APIS143 | Hdf | restriction-modification (RM) | CLAN028 | Escherichia phage P1 | PMID:28509398 | A key member in the P1 Dar antirestriction system. The absence of either Hdf or DarA results in failure to incorporate any of the other antirestriction proteins. |