Fig. 6

Expression and catalytic activity of MpADC-Δ39 variant. a Analysis of MpADC and MpADC-Δ39 expression by SDS-PAGE. M: protein marker; lanes 1 and 3: the supernatant of E. coli cells expressing MpADC and MpADC-Δ39; lanes 2and 4: the precipitation of E. coli cells expressing MpADC and MpADC-Δ39. b The relative activity of the cell expressing MpADC and MpADC-Δ39. Whole-cell catalysis was performed in a 1-mL reaction system containing 100 g/L fermented cells, 60 g/L L-ASP, 0.5 mM PLP (pH–6.5) on a magnetic stirrer (IKA® C-MAG HS 7) at 1500 rpm, 37 °C. After 5 min, the reaction was terminated by a 100 °C metal bath for 5 min. The experiment was performed in triplicate, and the standard deviations of the biological replicates were represented by error bars