Effects of some drugs on the activity of glucose 6-phosphate dehydrogenase from rainbow trout (Oncorhynchus mykiss) erythrocytes in vitro

Figures & data

Table I.  Purification scheme for glucose-6-phosphate dehydrogenase from rainbow trout erythrocytes.

Purification step	Activity (U/ml)	Total volume (ml)	Protein (mg/ml)	Total protein (mg)	Total activity (U)	Specific activity (U/mg)	Yield (%)	Purification factor
Haemolysate	0.241	50	38.4	1920	12.05	0.0062	100	1
Ammonium sulphate precipitation (40–65)%	0.754	14	1.41	11.28	10.55	0.534	87.5	86.13
2′, 5′-ADP Sepharose 4B affinity chromatography	2.315	4	0.15	0.6	9.26	15.43	76.8	2488

Figure 1 SDS-PAGE bands of G6PD. Lane 1: Rainbow trout erythrocytes G6PD. Lane 2: Chicken erythrocytes G6PD. Lane 3: Standards: E.Coli (galactosidase (116,000), rabbit phosphorylase B (97,400), bovine albumin (66,000), chicken ovalbumin (45,000), and bovine carbonic anhydrase (29,000).

Figure 2 Lineweaver-Burk graph in 5 different substrat (G6P) concentrations and 3 different marcaine concentrations for determination of K_i.

Table II.  K_i values obtained from Lineweaver-Burk graphs for G6PD 3 for different drugs.

Drug	I50 (mM)	Ki values (mM)	Mean Ki values (mM)	Inhibition type
Pental sodium	1.247	0.664	0.748 ± 0.11	Noncompetitive
		0.874
		0.706
MgSO4	85.555	11.446	12.119 ± 0.73	Competitive
		12.014
		12.897
Vancomycin	4.789	1.855	1.466 ± 0.40	Competitive
		1.492
		1.052
Metamizol	1.167	0.284	0.392 ± 0.10	Competitive
		0.389
		0.503
Marcaine	0.0329	0.0493	0.0446 ± 0.012	Noncompetitive
		0.0465
		0.0382
Prilocaine	0.392

Figure 3 Activity % vs [marcaine] regression analysis graphs for Rainbow trout erythrocytes G6PD in the presence of 6 different marcaine concentrations.