the antibacterial protein lysozyme identified as the termite egg recognition pheromone抗菌蛋白溶菌酶的白蚁卵识别信息素.pdfVIP

The Antibacterial Protein Lysozyme Identified as the Termite Egg Recognition Pheromone 1,2 3 1 1 1 Kenji Matsuura *, Takashi Tamura , Norimasa Kobayashi , Toshihisa Yashiro , Shingo Tatsumi 1 Graduate School of Environmental Science, Okayama University, Okayama, Japan, 2 Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America, 3 Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan Social insects rely heavily on pheromone communication to maintain their sociality. Egg protection is one of the most fundamental social behaviours in social insects. The recent discovery of the termite-egg mimicking fungus ‘termite-ball’ and subsequent studies on termite egg protection behaviour have shown that termites can be manipulated by using the termite egg recognition pheromone (TERP), which strongly evokes the egg-carrying and -grooming behaviours of workers. Despite the great scientific and economic importance, TERP has not been identified because of practical difficulties. Herein we identified the antibacterial protein lysozyme as the TERP. We isolated the target protein using ion-exchange and hydrophobic interaction chromatography, and the MALDI-TOF MS analysis showed a molecular size of 14.5 kDa. We found that the TERP provided antibacterial activity against a gram-positive bacterium. Among the currently known antimicrobial proteins, the molecular size of 14.5 kDa limits the target to lysozyme. Termite lysozymes obtained from eggs and salivary glands, and even hen egg lysozyme, showed a strong termite egg recognition activity. Besides eggs themselves, workers also supply lysozyme to eggs through frequent egg-grooming, by which egg surfaces are coated with saliva containing lysozy