Diversity of toxic components from the venom of the evolutionarily distinct black whip snake, Demansia vestigiata

Included among the more than 300 species of elapid snakes worldwide is the Australian genus Demansia, or whip snakes. Despite evidence to suggest adverse clinical outcomes from envenomation by these snakes, together with confusion on their true phylogenetic relationship to other Australian elapids, not a single toxin sequence has previously been reported from the venom of a Demansia species. We describe here a combined proteomic and transcriptomic approach characterizing the venom from the black whip snake, Demansia vestigiata. A total of 13 distinct toxin families were identified, including homologues of all of the major toxic components previously reported from the venom of other Australian elapids, such as factor X-like prothrombin activators, neurotoxins, phospholipases, cysteine rich secretory proteins, textilinin-like molecules, nerve growth factors, L-amino acid oxidases, vespryns, 5′ nucleotidases, metalloproteinases, and C-type lectins as well as a novel dipeptidyl peptidase family. Phylogenetic analysis of these sequences revealed an early evolutionary split of the black whip snake from all other characterized Australian snakes, with a low degree of sequence identity between D. vestigiata and the other snakes, across all toxin families. The results of this study have important implications not only for the further characterization of venom from whip snakes, but also for our understanding of the evolutionary relationship of Australian snake species.