TABLE 2.
B204 mutant activities in ATPase assays and transfection experiments
| Mutant | Target motif/predicted function | In vitro ATPase assay (nmol Pi/mg protein/min) | Transfection experiment resulta |
|---|---|---|---|
| WT | 315 ± 30 | + | |
| K13M | Walker A: GRMRSGKS | No detectable activity | Not tested |
| K13R | Walker A: GRRRSGKS | 128 ± 41 | – |
| R14M | Walker A: GRKMSGKS | No detectable activity | Not tested |
| R14K | Walker A: GRKKSGKS | No detectable activity | Not tested |
| K17M | Walker A: GRKRSGMS | No detectable activity | – |
| K17R | Walker A: GRKRSGRS | No detectable activity | – |
| E49K | Putative function in ATP binding/hydrolysis | No detectable activity | – |
| E49L | No detectable activity | – | |
| E49N | No detectable activity | – | |
| E49Q | No detectable activity | Not tested | |
| E104Q | Walker B: VLIIDQ | No detectable activity | – |
| R127E | Arginine finger | 54.4 ± 3.6 | – |
| R127K | 27.8 ± 3.6 | – | |
| R127M | 42.9 ± 12.4 | – | |
| Q138E | Triphosphate-sensing residue | 44.5 ± 9.5 | – |
| Q138N | 88.0 ± 17.5 | + | |
| D152A | Stabilizing residue | No detectable activity | – |
| D152N | No detectable activity | – | |
| K166A | Tunnel residue | 80.1 ± 8.6 | + |
| K170A | Tunnel residue | 675 ± 62 | + |
a
A dash indicates that the mutant generated qPCR values on par with those of uninfected controls, around 1 × 108 genomes/ml. The plus symbol indicates that the mutant generated qPCR values at levels comparable to that of the wild type, around 1 × 1012 to 1 × 1013 genomes/ml. The mutant particles generated from the first round of infection were capable of reinfecting the host. The boldface letters indicate the position being mutated in the context of the motif of interest.