Sponges play key roles in marine ecosystems in biochemical cycling, as habitat and food providers for several organisms of distinct taxa and they also host a number of marine microorganisms as symbionts. Despite their importance, the sponge-microbiota relationship and its stability are little studied, especially in polar regions such as the Antarctic continent, where they are expected to play an even more important role, compared to other latitudes, due to the extreme ambient conditions. The sponge genus Mycale is one of the most abundant groups within the Antarctic marine environment, but surprisingly so far only a few studies on its microbiota have been conducted. In relation to this, the aim of this work was to create a baseline of the microbiota associated with the ecologically important sponge Mycale (Oxymycale) acerata (Kirkpatrick, 1907) in South Bay, Doumer Island (WAP), assessing the taxonomical composition and stability of the microbiota at spatial and temporal scales. Therefore, the V4-V5 region of the 16S rRNA were sequenced using Illumina Miseq sequencing methods. The results revealed a relatively diverse microbial community, with Gammaproteobacteria as dominating group on the class level. OTU distribution analyses demonstrated high similarities between the hosts, and a dominance of a single OTU (OTU_001, Betaproteobacteriales). About 10% of the OTUs were shared by 75% of the samples, and only three were represented amongst all sponge individuals. Distinct diversity patterns could not be identified, neither at spatial nor at temporal scale.
Managing Thesis and Internship Exchanges
