Divya Gandhi

Prof. Krishnan's efforts have drawn together leading science organisations into a study of cone snail venom

BANGALORE: They might be known better for their exquisitely patterned shells, but cone snails are also some of the planet's most lethally venomous creatures. The slow, seemingly innocuous snail is in fact a highly sophisticated predator, which hunts fast-moving fish with its venom-coated harpoon, first stunning, paralysing and finally killing the prey.

India has a vast resource of 100 to 200 species of cone-snails. The possible medical application of conotoxin (or the neuro-toxin in cone snail venom) is an area of growing interest for Indian scientists. It has potential as a painkiller and in the treatment of neurological conditions such as epilepsy and post-stroke brain damage.

K.S. Krishnan, professor of Biological Sciences, Tata Institute of Fundamental Research (TIFR), Mumbai, has pioneered research on the marine snail in India.

While the pharmaceutical applications of conotoxins have been of growing interest internationally over the last two decades, it is Prof. Krishnan's efforts that have drawn together leading science organisations into a collaborative study of cone snail venom in India.

Nearly five years of work has now culminated in an application for a patent for some of the discoveries.

Cone snails are considered by scientists to have "more potential for new medicines than any other genus in nature". What sets cone snails apart from other venom-producing animals, explains Prof. Krishnan, is that each species contains an enormous diversity of neurotoxins, each of which targets specific nerve receptors of its prey. "While cobra venom contains one or two component toxins, cone snails have 100 to 200, which could offer a wealth of molecules that can be isolated and studied", Prof. Krishnan says.

These toxins have several virtues. "Their action being so exquisitely specific to their targets in the central nervous system, they would have fewer side-effects. And unlike most neurological drugs today (such as opium-based morphine), they promise to be non-addictive, and yet up to 1,000 times as potent," Prof. Krishnan says.

While the work so far has been to understand the basic property of these toxins, two peptide (a protein compound) sequences identified are in the final stages of being patented.