TABLE 2.
Kinetic parameters for deletion mutant transcripts
The relative Vmax/Km for the T. thermophilus wild-type tRNAPhe transcript was expressed as 100%. ND means that the kinetic parameters could not be calculated correctly. Not detectable means that the methyl group incorporation was not detectable under the tested condition.
| Transcript name | Km | Vmax | Relative Vmax/Km or relative initial velocity |
|---|---|---|---|
| nm | μmol mg−1 h−1 | % | |
| Full-length tRNAPhe | 130 ± 20 | 360 ± 60 | 100 |
| Transcript 15 | ND | ND | Not detectable |
| Transcript 16 | ND | ND | Not detectable |
| Transcript 17 | ND | ND | <5a |
| Transcript 18 | 280 ± 40 | 560 ± 90 | 75 |
| Transcript 19 | 200 ± 40 | 520 ± 70 | 95 |
| Transcript 20 | 200 ± 40 | 730 ± 120 | 135 |
| Transcript 21 | 220 ± 50 | 500 ± 60 | 85 |
| Transcript 22 | 250 ± 50 | 810 ± 100 | 120 |
| Transcript 23 | 270 ± 40 | 400 ± 90 | 25 |
| Transcript 24 | 130 ± 30 | 680 ± 70 | 190 |
a The relative initial velocities were calculated from the methyl group acceptance activities at 30-min periods. <5 means that the relative initial velocity was below 5% of that for T. thermophilus tRNAPhe.