Investigation of heavy metal effects on immobilized paraoxanase by glutaraldehyde

Abstract

Serum paraoxonase 1 (PON1) was purified from bovine serum using hydrophobic interaction chromotography on Sepharose 4B-coupled L-tyrosine 1-naphthylamine gel, and monitored by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Paraoxonase enzyme was immobilized using different ratios of glutaraldehyde and the maximum activity was observed with 7% glutaraldehyde. The effects of inhibition by Mn+2, Co+2 and Cu+2 heavy metals on the immobilized and free enzyme activities were studied. At the optimum pH and temperature, the K-m and V-max kinetic values for bovine serum paraoxonase and immobilized paraoxonase towards paraoxon substrate were determined as 0.296 x 10(-3) M & 37.04 EU vs. 0.727-10(-3) M & 36.36 EU, respectively.