SCIENCE LAB SPECIAL : RESEARCH GLOBAL ESSAY

Toxic Defenders : Don't mess with termites that wear backpacks : A video shows a termite worker under attack. Three enemies of another species scrambled over its body, limbs dancing and mandibles closing.

Suddenly, the attacked worker's back erupts and caustic foam pours from its body. It will die, but this fountain of toxic material may save its nestmates from the invaders.

A closer look shows two half-moons of deep blue embedded on this worker's back.  

Some years ago, scientists observing this species of termite, Neocapritermes taracua, in French Guiana realized that these blurry shapes were in fact solid knobs of potent enzyme, tucked into pockets in its carapace.

When the termite worker is confronted by dangerous foes, it will rupture a compartment and bring a hitherto mostly harmless fluid into contact with the enzyme, creating that lethal reaction.

Scientists wanted to get a better look at this perilous enzyme. 

In a paper published in the journal Structure, a team of biologists described a detailed analysis they made of the bluepack the termites carry, including an unusual bond they identified that may be linked to its deadly burst.

This termite is not the only insect that kills invaders by sacrificing itself, said Jana Skerlova, a structural biologist at the Czech Academy of Sciences and an author of the new paper.

A colonial ant species has been observed performing a similar behavior. When workers in a colony are sterile, they can help their own genes survive by protecting relatives that can reproduce.

What's special about Neocapritermes taracua is that until attacked, it keeps a relatively innocuous molecule physically separate from an enzyme, named blue Laccase BP76.

When blue Lacasse BP76 mixes with that molecule, a single hydrogen atom is removed turning it into a toxin.

The World Students Society thanks Veronique Greenwood.