BioProject

Ocean acidification (OA) is one of the major issues caused by the rising of atmospheric CO2 with immediate effects in the oceans carbonate chemistry. More...

Ocean acidification (OA) is one of the major issues caused by the rising of atmospheric CO2 with immediate effects in the oceans carbonate chemistry. The oceanic microbial communities are key players in the biochemical cycles of the marine ecosystem and are expected to respond to the ocean’s changing chemistry in a feedback loop of intertwined microbial mediated processes. While the microbial response and effect to OA is challenging to predict due to the complexity of the system, experimental manipulations under controlled conditions can help us understand the major mechanisms of microbial adaptation to a changing oceanic chemistry. In this work we established replicated mesocosms in order to evaluate the effect of decreasing ph in the microbial community composition and gene expression using metatranscriptomics. We examined the effect of both decreasing ph and increasing temperature, one of the major parameters that is expected to have synergistic effects on the microbial response to OA. We examined the effect of both decreasing ph and increasing temperature, one of the major parameters that is expected to have synergistic effects on the microbial response to OA. Additionally, we established mesocosms with either coastal or ocean waters, with the expectation to observe less gene expression responses from the coastal communities which are adapted to a constantly changing water chemistry in comparison to the more sensitive to change ocean communities. In order to account for the variation in gene expression profiles from environmental samples we established two replicates for each of the following incubations (a) control (b) acidified (-0.3 from the in situ ph) (c) warmed (+3oC from the in situ temperature) (d) warmed and acidified. Each mesocosm was maintained under stable conditions for 5 days, after which we isolated samples for 16S rRNA amplicon sequencing and metatranscriptomic sequencing. Additionally, we sequenced the metatranscriptome of the original coastal and ocean samples in order to obtain a baseline gene expression profile of the in situ communities. Less...