Fig. 5.
Comparison of activities for the saturation library at position 190 against F190Dpc variant. Activity of NAL variants bearing the 20 canonical amino acids at position 190 was measured using the TBA assay and compared with NAL bearing the Nca Dpc at position 190. Initial reaction rates were determined using the TBA assay under conditions where the time course of product formation is linear (Fig. S4). Steady-state kinetic parameters were determined at a fixed pyruvate concentration of 80 mM and erythrose concentrations between 0.8 and 15 mM. Each reaction contained 18 µg (0.52 nmol) of enzyme and were carried out in duplicate and data were fitted to the Michaelis–Menten equation. The fitted value ± SE of the fit is shown. (A) Comparison of kcat values; (B) Steady-state parameters.