Table 2. Apparent kinetic parameters of Ec‐CP1‐β and Ec‐CP1‐β′ in editing mischarged [3H]Ile‐tRNALeuGAG
ProteintRNALeu originkcatapp (s−1)Kmapp (μM)kcatapp/Kmapp (μM−1 s−1)kcatapp/Kmapp (relative)Loss of efficiency (‐fold)
Ec‐CP1‐βA. aeolicus0.12±0.025.60±0.521.4 × 10−311
E. coli1.7±0.2 × 10−216±2.81.06 × 10−30.0520
Ec‐CP1‐β′A. aeolicus2.1±0.3 × 10−231±3.80.68 × 10−30.03231
E. coli1.6±0.2 × 10−228±4.10.57 × 10−30.02737
  • Relative kcatapp/Kmapp and loss of efficiency values were expressed according to the most efficient catalyst (Ec‐CP1‐β with A. aeolicus tRNALeu). All values are the average of three experiments. E. coli tRNA2Leu was the isoacceptor used in the assays. kcatapp and Kmapp are apparent kcat and Km, respectively.