In biology, there is the concept of autosis, or suicidal self-sacrifice. This term refers to a protective technique used by some species of ants and termites: when the colony is threatened, some individuals initiate a reaction that tears their bodies apart. As they move, they spray a poisonous or sticky secretion at the attackers. For example, this type of self-sacrifice is performed by worker termites Neocapritermes taracua. An international group of scientists recently revealed details about the components of the “explosives” that previously remained a mystery.

A magazine article about kamikaze termites StructureThis is not the first study on the subject Neocapritermes taracuaIt lives in the tropical forests of French Guiana. Previously, scientists generally described these termites as “biological weapons.” In a new study, the authors revealed new details about it.

Throughout the life of workers N. taracua The deposits accumulate in a special pocket in the front of the body. These blue crystals, which contain an enzyme called blue laccase BP76, are one of the components of the termite’s explosives.

Mortals N. taracua become the most adult insects, weaker and less useful to the colony than the young. Summer worker termites, who have larger enzyme reserves, detonate an “explosive package” on their backs when they are in danger. The contents combine almost immediately with another substance from the insects’ bodies, whose molecules have hitherto been harmless to them.

When combined, the components form a sticky and poisonous mixture saturated with toxic benzoquinones. Under its influence, the suicide termite dies, simultaneously killing or immobilizing its competitors.

Researchers from the Czech Republic, Japan and France studied the three-dimensional structure of an “explosive” enzyme from termite back deposits using X-ray crystallography. They discovered an extremely strong bond between two amino acids, the building blocks of all proteins, near the active site of the enzyme. The latter, combining with molecules of another substance, initiate a reaction, resulting in the formation of a deadly secret.

The authors believe that this structure provides high stability and stability of laccase BP76. Due to the warfare, the link remains unchanged, maintaining its activity throughout the life of termites in tropical rainforest conditions. These features are very important for the defense mechanism, because in case of an attack on the colony it must be ready and activated immediately.

“Just as knowledge of individual components of a device sheds light on its functioning, understanding the three-dimensional structure, that is, the positioning of individual atoms in a molecule, helps understand biological processes,” commented Pavlyna RzhezachovaPavlina Zezakova), head of the laboratory conducting the research.