Nature’s most sophisticated biological weapon

Nature’s most sophisticated biological weapon, snake venom, largely evolved from bits of body parts a Melbourne researcher has found.

In the first comprehensive analysis of the origin and evolution of snake venom, Dr Bryan Fry from the University of Melbourne’s Australian Venom Research Unit says the findings may help to explain why snake venom is so effective.

“These findings help to explain the amazing diversity of ways that venomous snakes can kill their prey and why they have so much potential use in medial research,” he says.

In his research, Dr Fry found that rather that being derived from saliva, 21 of the 24 known snake venom toxins were found to have originally derived from proteins normally expressed in other body tissues, including brain, eye, lung, heart, liver, muscle, mammary gland, ovary and testis.

Only two were derived from proteins presumably expressed in reptile saliva and one did not have any similarity to any known proteins.

The findings will be published in the March edition of Genome Research.

Dr Fry says, “By recruiting and tweaking proteins from other body tissues, snakes developed a clever mechanism for creating more specific and highly potent toxins, ones that would cause their victims’ bodies to turn against themselves upon injection.”

Over time, these newly derived toxins became a normal part of the saliva protein repertoire, he says.

Dr Fry believes that his findings will further research efforts focussed on the use of snake toxins for therapy and treatment of diseases, including cancer, arthritis and heart disease.

“There is something peculiarly fascinating in the use of a deadly toxin as a life-saving medicine,” he says. “The natural pharmacology that exists within animal venoms is a tremendous resource waiting to be tapped.”