Table 1.
Kinetic parameters of isoleucylation by IleRS
| IleRS | Substrate tRNA | Km (μM) | kcat (×10−3 s−1) | kcat/Km (relative) | LAU/UAU of kcat/Km (relative) | |
|---|---|---|---|---|---|---|
| M. mobile WT | M. mobile tRNAIle2UAU (native) | 0.70 ± 0.11 | 270 ± 10 | 1.0 | ||
| M. mobile tRNAIle2LAU (synthetic) | 0.40 ± 0.02 | 310 ± 20 | 2.0 | } | 3.6 | |
| M. mobile tRNAIle2UAU (synthetic) | 1.0 ± 0.2 | 230 ± 20 | 0.57 | |||
| E. coli WT | E. coli tRNAIle2LAU (native) | 1.4 ± 0.4 | 260 ± 30 | 1.0 | ||
| E. coli tRNAIle2LAU (synthetic) | 0.25 ± 0.02 | 180 ± 10 | 3.9 | } | 360 | |
| E. coli tRNAIle2UAU (synthetic) | 8.3 ± 1.5 | 17 ± 4 | 0.011 | |||
| E. coli W905R | E. coli tRNAIle2LAU (synthetic) | 0.37 ± 0.07 | 130 ± 30 | 1.9 | } | 18 |
| E. coli tRNAIle2UAU (synthetic) | 1.9 ± 0.3 | 39 ± 2 | 0.11 |