Distinct microbial communities at hydrothermal vents

Microbial communities at deep-sea hydrothermal vents were investigated using molecular and geochemical analysis, elucidating patterns over temporal and spatial scales. Differences in micobial composition were found between sites, as well as less pronounced differences within sites over time. Key populations which manage carbon, sulphur, hydrogen and nitrogen levels were identified such as SUP05 at ‘Anemone’ site and methanogenic Archaea at ‘Marker 113’ site.

Findings focussed on microbial population dynamics over time, including their ability to maintain distinct communities, demonstrated by a vent eruption between sampling; many geophysical changes occurred but microbial structure remained stable. Seafloor sampling was interesting, revealing the substrate may act as a microbial ‘bank’.

Relationships between microbial communities and environmental factors were suggested, however these links must be treated with caution. Better communication of the statistical analysis about the differences would have helped highlight where major differences in microbial structure are found and inferences could have been made into why this is the case.

Deep-sea hydrothermal vents microbiomes are complex, this work highlights the variability that can be found, as sampling only took place once a year for three years per site, more regular sampling would be interesting to understand the dynamism of these unique communities.

Fortunato, C.S., Larson, B., Butterfield, D.A., Huber, J.A. (2018) Spatially distinct, temporally stable microbial populations mediate biogeochemical cycling at and below the seafloor in hydrothermal vent fluids. Environmental Microbiology, 20(2), 769-784. doi:10.1111/1462-2920.14011