Carnivorous plants are a great example of organisms adapting to extreme habitats. Most carnivorous plants grow in environments with nutrient-poor soils and high sun exposure. To obtain necessary elements, they developed carnivorous adaptations to receive their essential nutrients from their prey.

The Martin Lab is interested in the Cape sundew, which is also known as the Drosera capensis. The Cape sundew utilizes its elongated leaves covered in sticky trichomes to slow down its prey and then fold to close around the insect. Unlike carnivorous plants with enclosed digestive systems, such as Venus flytraps or pitcher plants, D. capensis performs digestion in an exposed environment subject to fluctuating temperature, humidity, and microbial competition. These conditions suggest the presence of highly stable and functionally robust digestive enzymes and antimicrobial peptides capable of maintaining activity under variable environmental conditions. We aim to obtain a holistic understanding of this organism’s physiology through a combination of genomic, transcriptomic, metabolomic, and proteomic methods.

The Martin Lab published the first draft genome of D. capensis in 2016, which allowed us to use predictive structural analysis of observed macromolecules. Particularly, we have predicted the structures of digestive cysteine proteases, chitinases, lipases, and antimicrobial peptides using the draft genome. We also used transcript annotation tools like the Computer-Assisted Sequence Annotation (CASA) workflow for enzyme discovery in D. capensis to identify active site residues. Recently, our group has compiled a transcriptomic-metabolomic study that maps some of the biochemical pathways in the D. capensis feeding cycle.

We now aim to experimentally characterize the digestive enzymes involved in the plant’s digestion through bottom-up proteomics to observe post-translational modifications and time-specific enzyme expression.