The use of polyacrylamide gel electrophoresis to quantitate activity of leucocyte elastase and to detect its activity in complexes of biological interest
Feinstein, G.; Janoff, A.
Analytical Biochemistry 71(2): 358-366
1976
ISSN/ISBN: 0003-2697 PMID: 1275239 Document Number: 102447
N-acetyl-DL-alanine-.alpha.-naphthyl ester (Ac-Ala-ONaph) was suitable for quantitative determination of human leukocyte elastase activity in polyacrylamide gel after cationic electrophoresis. The activity measurements using this method were linear within the range 0.7-8 .mu.g of leukocyte elastase. The method is applicable for quantitative determination of elastase activity using either purified enzyme or enzyme present in mixtures with other leukocyte proteins. Complexes of elastase with .alpha.1-antitrypsin, which are inactive against synthetic substrates, were not stained in the gels with Ac-Ala-ONaph. Complexes of elastase with partly purified, monospecific anti-elastase antibody, which were capable of hydrolyzing synthetic substrates, were also stained with Ac-Ala-ONaph in polyacrylamide gels.