A soldier of the species Mastotermes darwiniensis (termites)

A soldier of the species Mastotermes darwiniensis before (left) and after (right) secretion of potent antimicrobial oral fluids (white arrow).

Source: BAM, Department Materials and the Environment

The importance of soldiers to termite defense has long been recognized, but the contribution of soldiers to other societal functions, such as colony immunity, is less well understood. In this study we explored the role of soldiers in protecting nestmates against infection. Even though they are unable to engage in hygienic cleaning behavior, we find that the presence of soldiers of the Darwin termite, Mastotermes darwiniensis, significantly improves the survival of nestmates following fungal infection. We also show that the abundant oral secretions produced by Darwin termite soldiers contain a high concentration of proteins involved in digestion, chemical biosynthesis, and immunity. The oral secretions produced by soldiers are sufficient to protect nestmates against infection, and they have potent inhibitory activity against a broad spectrum of microbes. Our findings support the view that soldiers play an important role in colony immunization, and broaden our understanding of the possible function of soldiers during the evolution of termite societies.

Termite soldiers contribute to social immunity by synthesizing potent oral secretions
Shulin He, P. R. Johnston, B. Kuropka, S. Lokatis, C. Weise, Rudy Plarre, Hans-Jörg Kunte, Dino Peter McMahon
Insect Molecular Biology, Volume27, Issue5, October 2018, Pages 564-576
BAM Department Materials and the Environment, Division Biodeterioration and Reference Organisms