Purification and Characterization of Meprin a from Human Blood Serum

Abstract

Meprin A is a zinc metalloendopeptidase that displays activity against a variety of biologically active peptides.Meprin α was purified from Human blood serum.

The enzyme was isolatedfrom 100mlhuman blood serum, and

further purified by fractionation with DEAE-cellulose ion exchange chromatography andSephadex G-200 gel filtration. The molecular weight of the Meprin α was estimated by gelfiltration on Sephadex G-200 to be 216271Dalton. In addition, the determining of the approximate molecular weight of Meprin α enzyme by electrical migration technology (Electrophoresis) using sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (SDS-PAGE) in the presence of 2-mercaptoethanol, two  majorprotein fragments with a  molecular weight  of (124830±3000) Dalton were observed.

Thus the  enzyme is an oligomer,probably a diamer. Then, the optimum conditions of Meprin α enzyme showed the highest activity which it was at time of (10) minutes at pH = 7.2 and at (37°C), substrate concentration was about (0.625 mmol/ L) and the maximum Velocity (Vmax) was (90.17 unit / L), the value of (Km) by using Mikael’s Menten and Linwifer – Burk plot was (0.067) and (0.1) mmolar respectively.