| AD families | AD genes | Defense system | CLAN ID | Phages/MGEs | References | Description |
|---|---|---|---|---|---|---|
| APIS136 | nma1821 | restriction-modification (RM) | CLAN045 | Neisseria meningitidis | PMID:22102579 | hin1523, nma1821 and hia5 are all DNA adenine N6-methyltransferases. Plasmid DNA overexpressing these novel DNA methyltransferases was resistant to cleavage by many restriction enzymes sensitive to adenine methylation. |