THE EFFECT OF AL(3+) AND HG(2+) ON GLUCOSE 6-PHOSPHATE DEHYDROGENASE FROM CAPOETA UMBLA KIDNEY

Abstract

Glucose 6-phosphate dehydrogenase (EC 1.1.1.49; G6PD) is an important enzyme found in all mammal tissues, and produces NADPH in the metabolism. NADPH provides a reductive potential to maintain a balanced redox state within the cell. The aim of this study was to purify G6PD from Capoeta umbla kidney and determination of inhibition or activation effects of aluminium and mercury on enzyme activity. In this purpose, glucose 6-phosphate dehydrogenase was purified from Capoeta umbla kidney by using preparation of homogenate, ammonium sulphate precipitation and 2',5'-ADP Sepharose 4B affinity chromatography. Molecular weight of the enzyme was determined on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and the purified enzyme showed a single band on the gel with a molecular weight of 75 kDa. Moreover, K-i constants of Al3+ and Hg2+ were found as 0.98 +/- 0.084 and 0.57 +/- 0.019 mM, respectively. In conclusion, affinity of the Hg2+ to the enzyme was higher than Al3+