Project description:The marsh pitcher plant (Heliamphora sp.) is a genus of carnivorous plant in which the production of endogenous digestive enzymes is still dubious. In this study, we tried to elucidate these old doubts and we investigated the ability of prey digestion in H. parva, H. neblinae and hybrid H. heterodoxa x minor. The plants were fed on fruit flies and digestive fluids were analysed using LC/MS, Western blots and enzyme activity measurements for presence of endogenous digestive enzymes. All investigated species produced endogenous digestive enzymes similar to those found in other carnivorous plant genera and the sister genus Sarracenia. Among these are: aspartic protease, subtilisin-like protease, type III chitinase, beta-1,3-glucanase, glucosidase, GDSL lipase, thaumatin-like protein etc. Phosphatase and proteolytic activities increased over time irrespective of feeding status. Immunoblotting of aspartic protease showed that abundance of the enzyme in digestive fluid can accumulate over time without any prey stimuli. The species of the genus Heliamphora can be considered as truly carnivorous plants with ability to produce endogenous digestive enzymes, although these are probably strongly diluted by rain in natural habitat, questioning their ecophysiological significance.
