Role of Proteases in Penetration of Insect Gut by the Entomopathogenic Nematode Steinernema glaseri (Nematoda: Steinernematidae)

Differences in penetration routes and establishment rates of four entomopathogenic nematode species into four white grub species

“…may use histolytic enzymes to weaken the cuticle combined with physical pressure through thrusting movement. There is indirect evidence suggesting a role of histolytic enzyme in midgut penetration of S. glaseri in P. japonica larvae (Abu Hatab et al, 1995) and of S. carpocapsae in G. mellonella larvae (Simões, 1998). S. feltiae cuticle penetration in Tipula spp.…”

Behavioral ecology of entomopathogenic nematodes

“…Protease inhibitors decreased penetration of S. glaseri through the gut wall of P. japonica (AbuHatab et al, 1995) and the midgut epithelium cells of G. mellonella showed a marked histolysis in response to secretions of axenic S. carpocapsae (Simoes, 1998). Penetration by S. feltiae through the cuticle of leatherjackets might be attributed to the absence of an epicuticular wax layer, which may block the activity of histolytic enzymes (Dowds and Peters, 2002).…”

Susceptibility and immune response of Deroceras reticulatum, Milax gagates and Limax pseudoflavus exposed to the slug parasitic nematode Phasmarhabditis hermaphrodita

“…The use of enzymes has been shown for a number of parasitic nematode species to gain access to host systems resulting in tissue disruption including Ascaris suum (Knox and Kennedy, 1988) and Strongyloides ransomi (Dresden et al, 1985). AbuHatab et al (1995) reported Steinernema glaseri releasing proteolytic enzymes that increased the chances of entering through the gut wall of insect hosts. Interestingly, no lesions were observed on L. pseudoflavus, and it could be possible that this slug species may produce a lectin in its mucus that acts as a protease inhibitor, a phenomenon that has been reported for A. ater (Habets et al, 1979), which is also known to be resistant to P. hermaphrodita.…”