ASLO Aquatic Sciences Meeting location:Lake Biwa, Shiga, Japan date:8-13 July 2012
Animals harbor a dynamic and diverse symbiotic microbial community, these symbiotic microorganisms can have varying effects on their host depending on the type of interaction (i.e. mutualistic, commensal or parasitic). The environment can alter both the composition and functionality of the symbiont community, which in turn can affect the fitness of its host. We conducted experiments to investigate the effect of low-quality food on host-parasite dynamics using a three-species model (Daphnia [host]- White Bacterial Disease [parasite] – Microcystis [low-quality food]). Although Microcystis normally negatively affects Daphnia, it was found that in low concentrations it protects Daphnia against infection with White Bacterial Disease. Furthermore, we found that Microcystis produces antibacterial compounds. These results indicate that the environment (i.e. food) can affect an organism indirectly through an impact on its microbial symbionts. This led us to further investigate the effect of Microcystis on the Daphnia microbiota, and its consequences for the host. Here, I will present current research results and ongoing experiments on the influence of cyanobacteria on the symbiotic microbial community of Daphnia.