The planarian microbiome in response to external stressors - focus on silvernanoparticles

Abstract

Many animals live in close association with complex microbial communities. The so-called microbiomes include bacteria, bacteriophages, fungi and viruses and are believed to have a beneficial effect on the hosts physiology. However, little is known about the invertebrate microbiome and its composition, how it is influenced by external factors and its stability as well as its function for the host physiology and health. In this study, we characterized the microbiome of a freshwater predator, the planarian Schmidtea mediterranea. Bacteria were found in the mucus and gut and sequencing results indicate mainly the association of proteobacteria with lab cultivated Schmidtea mediterranea. In addition, we investigated how environmental changes influence the planarian microbiome by a combination of ARISA fingerprinting and 16S rRNA sequencing. Of the studied compounds (Cd, MMS and silver nanoparticles) and other external changes (different foods and antibiotics exposure), silver nanoparticles had the highest impact on the planarian microbiome. Future research will reveal if and how an altered microbiome is important for the planarian physiology.