07 Jan 2021
CLAIM-involved study investigates the influence of seasonability to the microbial community structure of biofilms in the deep Mediterranean Sea
CLAIM co-funded research paper is available in the Deep-Sea Research Part II: Tropical Studies in Oceanography journal. An international team of leading experts elaborated on the topic of microbial communities and their dependency on seasonability and orientation of surfaces.
Microbial communities have a strategy for attachment to surfaces, which is indicated by the rapid migration of biotic and abiotic surfaces in marine waters. This colonisation is proven to occur as a result from the formation of different microorganisms, namely biofilms or microfilms. Their evolution is being initiated by the consumption of organics to solid surfaces, leading to the attachment of the surrounding microbes to those surfaces. However, the scientific team involved in this study claims that there has not been detailed enough knowledge about the development of biofilm-associated microbial communities and the environmental parameters influencing biofilm development in the deep sea.
Relative abundances (as percentages) of bacterial phyla present in biofilms grown at different surfaces, seasons and orientation at 4500 m depth at site Nestor 4.5 in the Eastern Mediterranean Sea; only phyla with at least 1% of total DNA in at least one of the tested variables (surface, season, orientation) are shown; (A) relative abundance for each variable separately – (A1) all phyla; (A2) all phyla except Proteobacteria; (B) relative abundances in each season -– (B1) all phyla; (B2) all phyla except Proteobacteria.
The primarily focus of the study is placed onto the development of microbial community colonising solid surfaces at the deepest point at reach of the Mediterranean Sea. An experimental setup has been implemented for conducting the testings.
Aiming at following the succession of microbes on solid surfaces in the Mediterranean, an amplicon sequencing is utilised in order to reach a higher phylogenetic resolution. As such, the researchers were testing their hypothesis on the probability of seasonality to influence the composition of deep-sea bacterial biofilm communities.
The findings of the experimental work show that a total number of 64 bacterial phyla were discovered within the deep-sea biofilms, which suggests a higher microbial richness in these biofilms under the present conditions of the Mediterranean Sea. Additionally, the study revealed that the most common types of phyla attached to the solid surfaces were Gammaproteobacteria, Alphaproteobacteria and Betaproteobacteria, regardless of orientation or season.
Read the full paper here.