A rapid method of purification of human granulocyte cationic neutral proteases: purification and further characterization of human granulocyte elastase

Abstract

Human granulocyte elastase (EC 3.4.21.-) was isolated and purified (yield = 62%, purity = 91-100%) by a new short procedure using affinity chromatography using phenylbutylamine covalently linked to Affi-Gel. The granulocyte elastase was found to have a molecular weight of 34 400 by sodium dodecyl sulphate gel electrophoresis and the molecular weight obtained from the amino acid composition was 34 970. The composition of elastase purified from normal leucocytes showed some significant differences from that of enzyme purified by others from leukemic leucocytes. The granulocyte elastase hydrolysed typical pancreatic elastase substrates like Boc-Ala-ONp and Ac-(Ala)3-Nan. The enzyme was also found to have a weak enzymatic activity in hydrolysing acetyl-L-phenylalanine-alpha-naphthyl ester, a typical chymotrypsin substrate. A monospecific antiserum raised against the purified enzyme gave a single precipitin line with the pure enzyme and also with crude granular extract, both lines being identical.