Revue de Medecine Veterinaire, cilt.158, sa.8-9, ss.431-436, 2007 (SCI-Expanded)
The buffalo erythrocyte glucose-6-phosphate dehydrogenase (EC 1.1.1.49, G6PD) was purified using 2', 5'-ADP Sepharose 4B affinity chromatography. During the overall purification steps, enzyme fractions having a specific activity of 63.33 U/mg proteins were concentrated 781.8-fold with a yield of 43.84%, and the enzyme purity was confirmed by SDS-PAGE (a single band of ∼ 65 kDa). Then, some important drugs (Streptomycin, Vancomycin hydrochloride, Nafcillin and Dexamethasone) were investigated for in vitro enzyme inhibition, throughout determination of drugs IC50 values plotting % of activity vs. drug concentrations. According to IC50 values, dexamethasone and streptomycin were the most potent inhibitors (2.68 mM and 6.58 mM respectively) whereas Vancomycin hydrochloride exhibited moderate effects (IC50: 8.10 mM) and the Nafcillin inhibition was minimal (IC50 18.24 mM). Besides, streptomycin and dexamethasone acted as allosteric inhibitors according to Lineweaver-Burk graphs with low Ki constants (2.225 ± 0.409 mM and 1.649 ± 0.269 mM respectively). The involvement of the G6PD inhibition during the drug toxicity discussed was then discussed.