Hydrocarbon seepage in the deep seabed links subsurface and seafloor biospheres
Ruff, S. Emil
Ellefson, Emily D.
Brooks, James M.
Bernard, Bernie B.
Hubert, Casey R. J.
MetadataShow full item record
Marine cold seeps transmit fluids between the subseafloor and seafloor biospheres through upward migration of hydrocarbons that originate in deep sediment layers. It remains unclear how geofluids influence the composition of the seabed microbiome and if they transport deep subsurface life up to the surface. Here we analyzed 172 marine surficial sediments from the deep-water Eastern Gulf of Mexico to assess whether hydrocarbon fluid migration is a mechanism for upward microbial dispersal. While 132 of these sediments contained migrated liquid hydrocarbons, evidence of continuous advective transport of thermogenic alkane gases was observed in 11 sediments. Gas seeps harbored distinct microbial communities featuring bacteria and archaea that are well-known inhabitants of deep biosphere sediments. Specifically, 25 distinct sequence variants within the uncultivated bacterial phyla Atribacteria and Aminicenantes and the archaeal order Thermoprofundales occurred in significantly greater relative sequence abundance along with well-known seep-colonizing members of the bacterial genus Sulfurovum, in the gas-positive sediments. Metabolic predictions guided by metagenome-assembled genomes suggested these organisms are anaerobic heterotrophs capable of nonrespiratory breakdown of organic matter, likely enabling them to inhabit energy-limited deep subseafloor ecosystems. These results point to petroleum geofluids as a vector for the advection-assisted upward dispersal of deep biosphere microbes from subsurface to surface environments, shaping the microbiome of cold seep sediments and providing a general mechanism for the maintenance of microbial diversity in the deep sea.
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chakraborty, A., Ruff, S. E., Dong, X., Ellefson, E. D., Li, C., Brooks, J. M., McBee, J., Bernard, B. B., & Hubert, C. R. J. Hydrocarbon seepage in the deep seabed links subsurface and seafloor biospheres. Proceedings of the National Academy of Sciences of the United States of America, (2020): 202002289, doi: 10.1073/pnas.2002289117.
Suggested CitationChakraborty, A., Ruff, S. E., Dong, X., Ellefson, E. D., Li, C., Brooks, J. M., McBee, J., Bernard, B. B., & Hubert, C. R. J. (2020). Hydrocarbon seepage in the deep seabed links subsurface and seafloor biospheres. Proceedings of the National Academy of Sciences of the United States of America, 202002289.
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
Contribution of ocean, fossil fuel, land biosphere, and biomass burning carbon fluxes to seasonal and interannual variability in atmospheric CO2 Nevison, Cynthia D.; Mahowald, Natalie M.; Doney, Scott C.; Lima, Ivan D.; van der Werf, Guido R.; Randerson, James T.; Baker, David F.; Kasibhatla, Prasad S.; McKinley, Galen A. (American Geophysical Union, 2008-02-12)Seasonal and interannual variability in atmospheric carbon dioxide (CO2) concentrations was simulated using fluxes from fossil fuel, ocean and terrestrial biogeochemical models, and a tracer transport model with time-varying ...
Salt marsh sediment diversity : a test of the variability of the rare biosphere among environmental replicates Bowen, Jennifer L.; Morrison, Hilary G.; Hobbie, John E.; Sogin, Mitchell L. (2011-12-17)Much of the phylogenetic diversity in microbial systems arises from rare taxa that comprise the long tail of taxon rank distribution curves. This vast diversity presents a challenge to testing hypotheses about the effects ...
Orsi, William D.; Edgcomb, Virginia P.; Christman, Glenn D.; Biddle, Jennifer F. (2013-04-23)Scientific ocean drilling has revealed a deep biosphere of widespread microbial life in sub-seafloor sediment. Microbial metabolism in the marine subsurface likely plays an important role in global biogeochemical cycles1-3 ...