Proteinases of the European catfish Silurus glanis L.

Proteolytic enzymes are widely used in various fields of industry, agriculture, medicine and molecular biotechnology. The search for new proteinases with high activity and different specificity is still relevant. Using purification methods (desalination, gel-chromatography, ion-exchange chromatography) three pepsin isoforms were isolated from the gastric mucosa of European catfish Silurus glanis L., and three trypsin isoforms, three chymotrypsin isoforms and two elastase isoforms were isolated from pancreas. We present physical and chemical properties of the isolated enzymes: isotopic values, molecular weights, ranges of pH activity and pH stability, temperature optimum of action, effect of metal ions and inhibitors. The results obtained supplement the information on the physical and chemical properties of fish proteinases and reveal the peculiarities in the properties of European catfish proteinases. These data can be used in the educational process for the basic and special courses "Biochemistry" and "Fish Physiology".