A Cysteine Endopeptidase (“Dionain”) Is Involved in the Digestive Fluid ofDionaea muscipula(Venus’s Fly-trap)

Abstract

The carnivorous plant Dionaea muscipula (Venus's flytrap) secretes proteinases into the digestive fluid to digest prey proteins. In this study, we obtained evidence that the digestive fluid contains a cysteine endopeptidase, presumably belonging to the papain family, through inhibitor studies and partial amino acid sequencing of the major SDS-PAGE band protein. The name "dionain" is proposed for the enzyme.