| AD families | AD genes | Defense system | CLAN ID | Phages/MGEs | References | Description |
|---|---|---|---|---|---|---|
| APIS010 | Ocr | restriction-modification (RM);bacteriophage exclusion (BREX) | CLAN020 | T7 of E. coli | PMID:32338761 329108 12235377 11804597 | Ocr physically associates with BrxX methyltransferase to neutralizes their ability to both methylate and exclude incoming phage DNA. Ocr structurally mimics the DNA phosphate backbone and interacts directly with EcoKI (both the MTase and REase domain of this type I R–M enzyme), thereby interfering with the activity of this system. |
| APIS077 | CLAN020 | Proteus phage PM 116 | ||||
| APIS085 | CLAN020 | Escherichia phage T7 | ||||
| APIS087 | CLAN020 | Shigella phage ESh23 | ||||
| APIS091 | HOS17_gp01 | restriction-modification (RM);bacteriophage exclusion (BREX) | CLAN015 | T3 of E. coli | Andriianov et al., 2023 | T3 encodes a SAMase that circumvents the SAM-dependent Type I R-M defence of the host E. coli through cleavage of S-adenosyl-methionine (SAM). SAMase also allows T3 to evade BREX defence. |
| APIS093 | CLAN015 | Pantoea phage vB_PagP-SK1 |