Table 2 Kinetic parameters for pNP-glycoside hydrolysis by selected variant glucuronidases.

Variant

k_cat (s^-1)

K_M (μM)

k_cat/K_M (M^-1.s^-1 × 10³⁾

k_cat (s^-1 × 10^-3)

K_M (mM)

k_cat/K_M (M^-1.s^-1)

Wild-type

109 ± 42

260 ± 120

410 ± 20

6.0 ± 0.2

2.7 ± 0.7

2.2 ± 0.6

N566S

128 ± 36

7000 ± 2000

18 ± 4

28 ± 2

7.2 ± 2

3.9 ± 0.8

T509A

161 ± 30

420 ± 60

380 ± 30

10 ± 2

5.4 ± 2.9

1.8 ± 0.5

T/S/N/K

-

-

-

99 ± 18

0.35 ± 0.2

280 ± 140

A4.1

55 ± 19

2900 ± 500

19 ± 6

21 ± 5

1.8 ± 0.8

12 ± 2

A4.3

129 ± 13

200 ± 40

660 ± 180

15 ± 8

6.0 ± 0.3

2.5 ± 1.2

A4.5

58 ± 6

240 ± 30

240 ± 60

2 ± 1

2.4 ± 1.3

0.8 ± 0.3

B4.1

46 ± 8

1400 ± 300

32 ± 5

15 ± 5

2.7 ± 1.1

5.5 ± 1.3

A5.1

2.7 ± 0.8

89 ± 38

30 ± 16

148 ± 43

22 ± 5

6.8 ± 1.4

A5.2

83 ± 22

280 ± 110

300 ± 90

63 ± 12

7.3 ± 2.6

8.6 ± 1.2

Shuffled-1

-

-

-

46 ± 9

0.3 ± 0.1

166 ± 80

Shuffled-2

-

-

-

96 ± 17

0.5 ± 0.3

200 ± 134

Neutral-1

77 ± 21

35 ± 5

220 ± 90

-

-

-

Neutral-2

C4.1

83 ± 9

21.8

440 ± 80

73.6

190 ± 30

296

-

9

-

9.21

-

0.98