دراسة فعالية وخواص انزيم السايتدين دي أمينيز المنقى جزئياً من أنسجة دودة الارض Lumbricus terrestris (Linnaeus , 1758)

Abstract

AbstractThe present research includes a study of the activity and properties of enzyme cytidine deaminase (EC. 3.5.4.5) in the extract of earthworm Lumbricus terrestris.Maximum activity of the enzyme was obtained in a reaction mixture containing (300) μM of Tris-HCl buffer at pH (7.2) containing (8) μM cytidine as a substrate and a concentration of enzyme extract equal to (60) μg. The reaction mixture was incubated at (37)◦C for (15)min. Under the optimum conditions, the specific activity was found to be (31.76 ± 1.1) μM of uridine per min. per mg protein in the supernatant of L. terrestries extracts compared with (20.24 ± 0.31) μM of uridine per min. per mg protein. The Michaelis constant (Km) value was (1.81 × 10-3 M).The research also included an isolation and partial purification of CDA by gel filration chromatography using sephadex G-200, the number of purification folds for the CDA was (6), and the molecular weight was found to be a round (95000) D.