Purification, Characterization, and Effect of Thiol Compounds on Activity of the Erwinia carotovora L-Asparaginase

Table 2

Influence of different metal ions and reagents on L-asparaginase activity.

Addition	Concentration (mM)	Relative activity (%)
No addition	none	100
Na^+ (NaCl)	1.0	117
K^+ (KCl)	1.0	133
Mg^2+ (MgCl2)	1.0	24
Ca^2+ (CaCl2)	1.0	78
Mn^2+ (MnCl2)	1.0	71
Zn^2+ (ZnCl2)	0.5	06
Fe^3+ (FeCl3)	0.5	47
Hg^2+ (HgCl2)	1.0	0
Ni^2+ (NiCl2)	1.0	51
Cu^2+ (CuCl2)	1.0	0
Cd^2+ (CdCl2)	1.0	0
EDTA	0.5	117
L-Cysteine	25	148
L-Histidine	25	114
Glutathione (reduced)	0.5	136
Thiourea	0.5	114
Thioacetic acid	0.5	106
Thioacetamide	0.5	110
2-mercaptoethanol	0.5	112
Dithiothreitol	0.5	86
p-chloro mercury benzoic acid	0.5	0
Iodoacetamide	0.5	0
Sodium dodecyl sulfate	2.0	119
	3.0	22
Urea	2.0	108
H2O2	1.0	24