We have isolated several new toxins which do not belong to any of the known families of snake venom toxins. Currently, we are examining their structure and biological properties.

• Helveprins : We have purified 15 members of this family from several snake venoms. This group of proteins appears to be found in the venoms of all families of snakes. They are structurally homologous to helothermine, a toxin isolated from Mexican lizard venom and hence the name.
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• Waprins : We have recently identified three novel proteins of this family. One of the member, Omwaprin exhibited antibacterial activity against gram-positive bacteria. They are homologous to whey acidic proteins and secretory leukocyte proteinase inhibitors. We will examine their structure and function.

• Vespryns : We have completed the amino acid sequence a toxin, ohanin from King cobra venom. This is similar to a thaicobrin from Thai cobra. This protein has a potent hypolocomotory activity. We have completed its cDNA and gene structure. We are currently studying its structure-function relationships and mechanism of action.

• Inflamins: From the transcriptome of Aipysurus eydouxii venom gland, we identified a novel cysteine-rich, secretory protein containing 94 amino acid residues. Recombinantly expressed protein induced inflammation and writhing in animals, and hence this protein was named as inflamin. We examined the mechanism of action of this protein. It induced two waves of prostanoids production. The first wave peaked at 10 min and 6-keto PGF1? was the major product. The second wave, specifically of 6-keto PGF1? and PGE2, started after 2 h. In RAW264.7 cells, COX-1 activity showed a transient increase at 10 min and is responsible for the first wave, but its expression was unaffected. COX-2 was induced after 3 h and is responsible for the second wave. Using specific inhibitors, we showed that cPLA2, and not sPLA2, iPLA2 or DAG lipase, plays a key role in arachidonate release. The cPLA2 activity showed a transient increase of 62% at 10 min; this increase was due to its phosphorylation and not due to an increase in its expression. Inflamin is the first member of a new family of snake venom proteins, we named as flamins.

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