The Properties of human serum and porcine kidney prolidase

ABSTRACT M.S. Thesis THE PROPERTIES OF HUMAN SERUM AND PORCINE KIDNEY PROLIDASE Emine Sibel NAMDURU Gaziantep University Graduate School of Health Sciences Department of Biochemistry Supervisor : Assoc.Prof. Yüksel ÖZDEMİR January- 1999 - 74 Pages The aim of this study is to evaluate the optimal conditions of the assay and kinetic properties of human serum and purified porcine kidney prolidase. The human serum prolidase activity was obtained by using sera pool from 30 healthy subjects. The effects of some metal ions ( Mn"2, Fe+2, Zn+2, Hg+2, Mg+2,Cu+2, Sr+2 ) and substances ( EDTA, IAA. p-CMBA and glutathione) were also investigated. Optimum conditions of serum and porcine kidney prolidase assay were found as follows ; preincubation at 37 °C, for 2 hours with final Mn*2 concentration 2.5 mmole/l and buffer concentration 40 mmole/1 (pH : 8). With Mn+2 ion the serum and porcine kidney prolidase activities were increased 23 and 9.5 times respectively. The final substrat concentration (gly-pro) of serum prolidase was 30 mmole/1 and it was 40 mmole/1 for inporcine kidney prolidase. The Km values of serum and porcine kidney prolidase were found as 13 mmole/1, 11 mmole/l for gly-pro and 14 mmole/1, 12 mmole/I for ala-pro substrates respectively. There is no activator effects of used metal ions except Mn+2 on human serum enzyme activity. However these metals indicate partial activator effect on porcine kidney prolidase. It is shown that Mn+2 ion is the most activator agent for prolidase. EDTA, IAA; and p-CMBA have been inhibited both human serum and porcine kidney prolidase but this effect was more effectively in preincubation compare to incubation. As a result of this study we thought that known of optimal working conditions and specifications of enzyme with an easy and true assay would be valuable for further investigations. Key words : Serum prolidase, porcine kidney prolidase, kinetic properties, inhibition. IV