Table 2.
Aminoacylation levels of tRNAAla mutants in vitro and in vivo
| tRNA mutant | Catalytic efficiency loss | Level of aminoacylation, %*
|
||
|---|---|---|---|---|
| In vitro | In vitro (+EF-Tu and PPase) | In vivo† | ||
| YFA2 (wild type)‡ | 1 | 25 | 100 | 100 |
| G73 | 58 | 14 | 93 | nd |
| C3⋅C70 | 83 | 4.1 | 52 | 72 |
| A70 | 338 | 8 | 51 | 81 |
| C3⋅A70§ | 436 | 2.0 | 25 | 74 |
| A3 | 1,952 | <0.1 | 3.8 | 3.8 |
| C70 | 2,145 | <0.1 | 4.2 | 2.1 |
*
The aminoacylation level was measured at 1 μM tRNA and 250 nM AlaRS; EF-Tu was added to 2 μM.
†
In vivo data are taken from ref. 17. Numbers are normalized to the aminoacylation level of wild-type tRNA. nd, not determined.
‡
Aminoacylation in vivo is measured in the background of wild-type tRNAAla.
§
The aminoacylation level of this mutant with Phe was 65% compared to more than 85% for all other tRNAs. Number in the table corresponds to the corrected value.