Studying of Metallo Endopeptidase and its Relation with Chronic Renal Failure

Abstract

The research includes a biochemical study of metalloendopeptidase in the blood, which is divided into two parts: The first part includes purification of metallo endopeptidase from plasma. It has been found that the specific activity and the number of purification is (5.07U/mg) and (33.13) respectively for the aqueous solution of the ammonium sulphate precipitation of the plasma (peakA) using gel filtration technique. In addition to that, It has been found that the enzyme has approximate molecular weight (86000±1000) dalton using the same technique. It has been demonstrated that metallo endopeptidase contains zinc and calcium elements, which is a kind of glycoproteins .The optimal conditions to analyze the casein substrate in one minute and pH optimum (6) using citrate buffer at (40ºC) and a substrate concentration of (0.25mM). Maximum velocity and Mich-menten were determined and found to be (0.4U/ml) (0.04mM)respectively. The enzyme activity was studied using gramicidin S and insulin as a substrate which showed high activity, while the activity was decreased by bovine serum albumin compared with casein. The enzyme activity decreased when EDTA and manganese acetate were used.The second part includes a clinical study of metallo endopeptidase in the serum of individuals and patients with chronic renal failure. It has been shown that the normal value of metallo endopeptidase is (14.19±0.36)U/ml of the control group for both sexes, their ages ranged between (20-70) year. There was a significant increase in the enzyme activity (17.53±0.53)U/ml in the serum of the patients affected by chronic renal failure from both sexes. It was also obvious that enzyme activity was not effected in control and patients group by age, sex and smoking while the increase of activity was demonstrated with the increase of the disease's period as well as there was a significant increase in the enzyme activity in the patients affected by diabetes mellitus and hypertension and diabetes mellitus or heart diseases, aside from chronic renal failure . A significant increase has been shown at urea, magnesium and potassium levels, while there was a significant decrease of total protein, albumin, calcium, zinc and sodium levels. However, no significant difference was noticed at globulin and copper levels for patient group compared with the control group. Finally a linear correlation coefficient between the activity and each of the total protein, albumin, globulin, potassium and copper in the control group was observed, and a significant correlation between the activity and each of the total protein, globulin, zinc and copper in the patients group