Community structure and antifungal activity of actinobacteria in a fungus‐growing termite

Abstract

Fungus‐growing termites cultivate the fungal mutualist Termitomyces as their main food source; however, how fungus‐growing termites protect Termitomyces from threats is still unclear. In this study, we investigated the actinobacterial communities in Odontotermes formosanus individuals and their fungal combs.
Moreover, the antifungal activities of the isolated actinobacteria were tested. 16 S rRNA gene sequencing results indicated that the actinobacteria in O. formosanus and its fungal combs belong to 5 classes, 17 orders, 40 families, and 84 genera.
The relative abundance of Coriobacteriia in the nymphs, young workers, old workers, and soldiers was higher than that in the queens and fungal combs, and the relative abundance of class Actinobacteria in the queens and the fungal combs was higher than that in the nymphs, young workers, old workers, and soldiers.
Based on antifungal bioassays, 3 strains of Amycolatopsis and 2 strains of Streptomyces isolated from old workers had strong inhibitory activity against Xylaria angulosa but weak inhibitory activity against Termitomyces sp.
These results indicated that the actinobacteria of O. formosanus may contribute to protecting termite fungal food via their asymmetric antifungal activities.