Identification of a Key Enzyme in the Digestion of Wool by Larvae of the Webbing Clothes Moth,Tineola bisselliella

Abstract

An important step in the digestion of wool by certain insect pests is the reductive cleavage of protein disulphide bonds to open the fibre for protease action. For larvae of the webbing clothes moth, Tineola bisselliella, two enzymes have been suggested as being involved in this process, cystine reductase and cysteine lyase/desulphydrase. In the present study, cystine reductase is shown not to be present in T. bisselliellalarvae. An earlier study, showing that cysteine lyase/desulphydrase is present in these larvae, is confirmed and extended to demonstrate that the activity is localised to the gut of larvae. This activity is also present in the larval gut of another clothes moth, Tinea pellionella, but is absent from the gut of the carpet beetle, Anthrenus flavipes, suggesting that larvae of moths and beetles use different mechanisms to reduce the disulphide bonds of wool.