Identification of novel proteins from the venom of a cryptic snake Drysdalia coronoides by a combined transcriptomics and proteomics approach.

We have investigated the transcriptome and proteome of the venom of a cryptic Australian elapid snake Drysdalia coronoides. To probe into the transcriptome, we constructed a partial cDNA library from the venom gland of D. coronoides. The proteome of the venom of D. coronoides was explored by tryptic digestion of the crude venom followed by HPLC separation of the resulting peptides and MALDI-TOF/TOF mass spectrometric analysis. Importantly, the tandem MS data of the tryptic peptides of the venom not only confirmed the predicted protein sequences deduced from the transcriptome, but also added to our knowledge about the venom composition through identification of two more toxin families. Using both the approaches, we were able to identify proteins belonging to eight different snake venom protein superfamilies, namely, three-finger toxins, serine protease inhibitors, cysteine rich secretory proteins, phospholipases A(2), venom nerve growth factors, snake venom metalloproteases, vespryns, and a new family phospholipase B. We also identified three novel proteins belonging to the three-finger toxin superfamily.