Substrate
Free GHTHase
PEG-GHTHase
K
m
(mM)
V
max
Umg
-1
min
-1
K
cat
min
-1
K
cat
/
K
m
mM
-1
min
-1
K
m
(mM)
V
max
Umg
-1
min
-1
K
cat
min
-1
K
cat
/ K
m
mM
-1
min
-1
Glutathione
14.3 ± 2.0
277.7 ± 65
0.078
0.0063
20.1 ± 4.0
212.7 ± 57
0.06
0.0029
L-Cysteine
15.1 ± 2.3
200.1 ± 43
0.056
0.0004
17.2 ± 3.2
136.9 ± 29
0.038
0.0023
L-Lysine
40.2 ± 4.2
120.0 ± 25
0.043
0.0012
13.2 ± 2.9
133.3 ± 30
0.037
0.0029
Table 1:
Kinetics of substrates specificity for free and PEG-GHTHase towards glutathione, L-cysteine and L-lysine as hydrogen donors acceptor. Means and SE for three replicates were calculated using student t-test.
