Table 1. In vivo wild-type and mutant HhaI DNA methyltransferase activities.
| M.HhaI | Colonies (mcr –/mcr+) |
|---|---|
| Wild-type | 102/0 |
| F18S | 58/0 |
| F18C | 72/88 |
| F18Y | 66/0 |
| F18W | 81/0 |
| F18H | 110/0 |
| L100S | 84/0 |
| D60P | 109/89 |
| D60N | 96/0 |
| W41A | 75/0 |
| W41I | 79/0 |
| W41Y | 72/0 |
Plasmids containing wild-type and mutant M.HhaI genes were transformed into an E.coli strain that expresses the mcrBC restriction system or a strain mutant for the mcrBC system, (ER1564 and ER1727, respectively). The number of colonies obtained on both the strains was compared. The numbers denoted are the average of three different experiments.