ABSTRACT
Chitinolytic enzymes are secreted into the culture medium by the epithelial insect cell line from Chironomus tentans, which was cultured essentially as described by C. Wyss. To characterize the chitinases of Lucilia cuprina, an investigation was conducted covering the determination of kinetic and some physicochemical parameters. In addition to these investigations the molecular weight patterns of chitinases from different important classes of veterinary parasites and life stages were determined. Different developmental stages of insects and tick were demonstrated to express chitinolytic enzymes of different molecular weights. Melanin binds both to the substrate chitin and to the degrading enzyme, posing the still unresolved question whether it functions as an enzyme inhibitor or simply as a physical barrier that prevents the access of chitinase to its appropriate substrate. A test system for quantitative determination of inhibitory effects on chitin-metabolizing enzymes was established.
