Characteristics of digestive proteases in the gut of some insect orders

Abstract

Gut proteases of 20 species from 13 insect orders were characterized by activity staining after polyacrylamide gel electrophoresis and the effect of class-specific protease inhibitors on their zymogram. Species in Orthoptera, Dictyoptera, Lepidoptera and Hymenoptera mainly had serine proteases in their gut. Those in Ephemeroptera, Odonata, Plecoptera and Hemiptera had cysteine proteases. Those in Coleoptera, Neuroptera, Mecoptera and Diptera had both serine+cysteine proteases in their gut. The protease class of each species tended to reflect phylogenetic relationship rather than feeding habits.