. 2016 Jul 8;17:15. doi: 10.1186/s12858-016-0070-0

Table 5.

Kinetic parameters of the purified wild-type and mutant enzymes toward oNPG as substrate

Enzyme	V_max (IU/mg)	K_m (mM)	K_cat (s⁻¹)	K_cat/K_m s⁻¹mM⁻¹	K_cat/K_m (%)
Wild-type LacA	2.61 ± 0.12	9.28 ± 0.72	21.74 ± 0.99	2.35 ± 0.08	100
LacA-301 V	0.76 ± 0.02	5.57 ± 0.56	3.72 ± 0.09	0.67 ± 0.08	28.65
LacA-361Y	1.03 ± 0.03	8.02 ± 0.27	8.56 ± 0.24	1.07 ± 0.01	45.50

K _m Michaelis constant, K _cat turnover rate, K _cat /K _m catalytic efficiency

The relative activity of β-galactosidase was determined in 100 mM buffer Z (pH 7.0) at 55 °C with oNPG as a substrate