Speaker
Description
Beneficial associations between insects and microbes are widespread, however our understanding of complex microbial communities with intricate interactions between the members and their influence on composition and functionality of symbiosis remains limited. We address symbiont-symbiont interactions in the context of a multipartite defensive symbiosis. Lagria villosa (Coleoptera: Tenebrionidae) engage in a symbiosis with multiple strains of Burkholderia gladioli that protect the beetle’s offspring from fungi. B. gladioli Lv-StB produces the antifungal compound lagriamide, B. gladioli Lv-StA is culturable in vitro and has the ability to produce multiple secondary metabolites that confer protection against fungi. To investigate the strain dynamics during colonization, Lv-StA was applied to Lv-StB infected eggs and larvae. Both strains could colonize the beetle’s organs individually, in combination, and in succession, indicating that the strains do not outcompete each other and the symbiosis remains open to environmental microbes. To study the impact of individual secondary metabolites produced by Lv-StA, we generated single knockout mutants and started conducting in vivo bioassays against a fungal antagonist of Lagria villosa. We anticipate to reveal if one compound or a combination of multiple compounds is needed for the defense. We hope to contribute to the understanding of symbiont-symbiont interactions in complex systems.
