Determination of the proteolytic activity of beef liver by means of natural substrates labed with 125 i
Blahovec, J.; Ondrus, I.
Veterinarni Medicina 20(7): 399-406
1975
ISSN/ISBN: 0375-8427 PMID: 841 Document Number: 83357
There is a description of the determination of the enzymatic activity of acid proteinases: the method is based on the use of 125J-labelled natural protein substrates. Labelled albumin 125J, globulin 125J, and insulin 125J were tested for the determination of activities. All the substrates were hydrolyzed with the enzymes of the supernatant fraction (106 000 g) of beff liver homogenate in the zone of acid pH. Optimum comditions of enzymatic reaction were tested, the dependence of reaction on the concentration of the enzyme, on time, and on temperature was determined, pH optimum was ascertained for individual substrates, and pH stability was determined. It follows from the results that the method is suitable for the determination of the enzymatic activity of proteinases of the cathepsin character.