Abstract
Peptidases comprise a large class of hydrolytic enzymes in parasitic nematodes, participating in nutrition through digestion of host proteins. They also act in the moulting and resorption of the cuticle by processing and activating proenzymes or prohormones, degrading proteins that anchor the epidermis to the underlying cuticle (apolysis), or by digesting the cuticle for resorption or facilitating its shedding (ecdysis).
They are also active during embryonic development of the egg. Peptidases are important in host-parasite relationships, being important virulence factors in some parasites.
The pathogenicity of several species of nematode has been significantly correlated with their peptidase activity. These include Strongyloides stercoralis, Anisakis simplex, Onchocerca volvulus, Trichinella spiralis, and Ancylostoma caninum.