Bioresources and Bioprocessing

Table 2 Kinetic parameters of the wild-type CadA and its mutants

From: Enhanced thermal and alkaline stability of L-lysine decarboxylase CadA by combining directed evolution and computation-guided virtual screening

mutant	pH 5.5 and 37 ºC			pH 8.0 and 50 ºC
mutant	K_m (mM)	K_cat (s⁻¹)	K_cat/K_m (s⁻¹·mM⁻¹)	K_m (mM)	K_cat (s⁻¹)	K_cat/K_m (s⁻¹·mM⁻¹)
WT	1.52 ± 0.15	81.09 ± 4.53	53.34	3.3 ± 0.69	73.75 ± 0.94	22.35
K477R	1.17 ± 0.25	83.59 ± 5.63	71.44	1.52 ± 0.17	79.26 ± 0.48	52.14
E445Q	1.44 ± 0.23	79.33 ± 3.79	55.09	2.64 ± 1.06	67.35 ± 1.68	25.51
F102V	1.66 ± 0.27	80.08 ± 6.32	48.24	3.01 ± 0.50	69.01 ± 0.89	22.92
K477R/E445Q	0.96 ± 0.21	83.53 ± 3.42	87.00	2.45 ± 0.25	71.69 ± 0.42	29.26
K477R/E445Q/F102V/T88S	1.09 ± 0.63	83.66 ± 4.67	76.75	1.78 ± 0.78	82.76 ± 3.67	46.50

Kinetic measurement at various lysine concentrations (0.4–8 mM) were performed at pH 5.5 and 37 ºC, or at pH 8.0 and 50 ºC in sodium acetate buffer solution. The results are presented as means ± standard deviations for triplicate experiments

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