Purification of human serum angiotensin I-converting enzyme by affinity chromatography

✍ Scribed by Robert B. Harris; John T. Ohlsson; Irwin B. Wilson

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 742 KB
• Volume: 111
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(81)90558-3

✦ Synopsis

A relatively simple procedure is described for purifying human serum angiotensin-converting enzyme. The enzyme was purified 130,000-fold to electrophoretic homogeneity using affinity chromatography as the principal purification step. The ligand was an immobilized competitive inhibitor, D-cysteinyl-L-proline. A six-carbon spacer arm was satisfactory for trapping the enzyme; 80% of the bound enzyme was eluted with 3 M urea-1 .O M NaCl-0.1 M Tris, pH 8.3. The specific activity was 39 units/mg protein and the molecular weight (155,000), isoelectric point (4.7) kinetic properties. and the effect of various inhibitors are in agreement with published reports.