Evidence for hydrogen oxidation and metabolic plasticity in widespread deep-sea sulfur-oxidizing bacteria
Breier, John A.
Sheik, Cody S.
Dick, Gregory J.
MetadataShow full item record
Hydrothermal vents are a well-known source of energy that powers chemosynthesis in the deep sea. Recent work suggests that microbial chemosynthesis is also surprisingly pervasive throughout the dark oceans, serving as a significant CO2 sink even at sites far-removed from vents. Ammonia and sulfur have been identified as potential electron donors for this chemosynthesis, but they do not fully account for measured rates of dark primary production in the pelagic water column. Here we use metagenomic and metatranscriptomic analyses to show that deep-sea populations of the SUP05 group of uncultured sulfur oxidizing Gammaproteobacteria, which are abundant in widespread and diverse marine environments, contain and highly express genes encoding group 1 Ni-Fe hydrogenase enzymes for H2 oxidation. Reconstruction of near-complete genomes of two co-occurring SUP05 populations in hydrothermal plumes and deep waters of the Gulf of California enabled detailed population-specific metatranscriptomic analyses, revealing dynamic patterns of gene content and transcript abundance. SUP05 transcripts for genes involved in H2 and sulfur oxidation are most abundant in hydrothermal plumes where these electron donors are enriched. In contrast, a second hydrogenase has more abundant transcripts in background deep sea samples. Coupled with results from a bioenergetic model that suggest that H2 oxidation can contribute significantly to the SUP05 energy budget, these findings reveal the potential importance of H2 as a key energy source in the deep ocean. This study also highlights the genomic plasticity of SUP05, which enables this widely distributed group to optimize its energy metabolism (electron donor and acceptor) to local geochemical conditions.
Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences of the United States of America 110 (2013): 330-335, doi:10.1073/pnas.1215340110.
Showing items related by title, author, creator and subject.
Meredith, Laura K.; Commane, R.; Munger, J. W.; Dunn, A.; Tang, Jianwu; Wofsy, Steven C.; Prinn, Ronald G. (Copernicus Publications on behalf of the European Geosciences Union, 2014-09-03)Our understanding of biosphere–atmosphere exchange has been considerably enhanced by eddy covariance measurements. However, there remain many trace gases, such as molecular hydrogen (H2), that lack suitable analytical ...
Meredith, Laura K.; Rao, Deepa; Bosak, Tanja; Klepac-Ceraj, Vanja; Tada, Kendall R.; Hansel, Colleen M.; Ono, Shuhei; Prinn, Ronald G. (2013-10)Microbe-mediated soil uptake is the largest and most uncertain variable in the budget of atmospheric hydrogen (H2). The diversity and ecophysiological role of soil microorganisms that can consume low atmospheric abundances ...
Antioxidant responses and lipid peroxidation in gills and erythrocytes of fish (Rhabdosarga sarba) upon exposure to Chattonella marina and hydrogen peroxide : implications on the cause of fish kills Woo, Stephanie P. S.; Liu, Wenhua; Au, Doris W. T.; Anderson, Donald M.; Wu, Rudolf S. S. (2006-05-20)Chattonella marina, a red tide or harmful algal bloom species, has caused mass fish kills and serious economic loss worldwide, and yet its toxic actions remain highly controversial. Previous studies have shown that this ...