In deep-ocean hydrothermal vent systems, oxidation-reduction (redox) reactions involving sulfur are known to fuel primary production via chemosynthesis. The particulate sulfur pool within buoyant hydrothermal plumes available to microorganisms as metabolic substrates remains undescribed. In this study, buoyant hydrothermal plume particles were collected from the Von Damm Vent Field, Mid-Cayman Rise, Caribbean. A novel in situ filtration system and remotely operated vehicle were used to collect samples along vertical profiles above two sites close to the summit of Mount Dent. Particulate sulfur speciation was measured using sulfur 1s X-ray absorption near edge structure (XANES) spectroscopy. The activity of sulfur-cycling genes in the buoyant plume was measured using metatranscriptomic sequencing. Our results indicate that both solid-state sulfur chemistry and microbial activity within the Von Damm buoyant plume are dynamic and diverse over short temporal and spatial scales. The particulate sulfur species and sulfur-cycling microbial communities generated in the buoyant plume are inputs to the neutrally buoyant plume and thus have potential for distant transport in the deep ocean. The buoyant plume particulate sulfur species include metal sulfides, thiol and organic monosulfide, thiophene, sulfone, sulfonate, ester sulfate, and sulfate. The microbial community carries a suite of active sulfur-cycling proteins (dsrAB, the sox enzyme complex, sqr, psr, dprAB, and SAT). Should these materials be exported to the neutrally buoyant plume, they will have implications for deep-ocean biogeochemistry through sustained biomass production based on sulfur oxidation and reduction.
Bibliographical noteFunding Information:
National Science Foundation (OCE-1061863 to C.R.G. and J.S.S. and OCE-1028990 to J.A.B.); National Aeronautics and Space Administration (NASA) Astrobiology Science and Technology for Exploring Planets (ASTEP) Program (NNX09AB75G to C.R.G. and J.S.S.); the National Science Foundation Graduate Research Fellowship Program and the University of Minnesota Graduate School Doctoral Dissertation Fellowship Program (B.R.C.); and the Gordon and Betty Moore Foundation (G.J.D., J.A.B., B.M.T., and 2764 to J.A.B.).
We thank the ROV JASON2 operations team, the R/V Atlantis crew (AT18–16), and the OASES 2012 science party for assistance and support with all aspects of the cruise. We thank Sarah Bennett for shipboard collaboration on sample collection and preservation; Yongfeng Hu, Edward Burton, Kathryn Nagy, and Alain Manceau for donating sulfur reference spectra; William Seyfriend for providing metal sulfide specimens; and Sarah Nicholas, Jeffry Sorensen, Rebecca Sims, Colleen Hoffman, Matthew Marcus, Josep Roque-Rosell, Sirine Fakra, Teng Zeng, Olga Furman, Jill Coleman Wasik, David Vine, Benjamin Stripe, Yongfeng Hu, Aimee MacLennan, Antonio Lanzirotti, Matthew Newville, and Qunfeng Xiao for assistance with synchrotron data collection. Data for this study were collected at the Advanced Light Source (ALS) beamline 10.3.2, the Advanced Photon Source (APS) beamlines 13-ID-E and 2-ID-B, and the Canadian Light Source (CLS) beamline SXRMB. The ALS is supported by the Director, Office of Science, Office of Basic Energy Sciences, U.S. Department of Energy (DOE), under Contract DE-AC02-05CH11231. Portions of this work were performed at GeoSoilEnviroCARS (The University of Chicago, Sector 13), APS, Argonne National Laboratory. GeoSoilEnviroCARS is supported by NSF Earth Sciences (EAR-1634415) and DOE GeoSciences (DE-FG02-94ER14466). This research used resources of the APS, a DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract DE-AC02-06CH11357. The CLS is supported by the Canada Foundation for Innovation, the Natural Sciences and Engineering Research Council of Canada, the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council of Canada, and the Canadian Institutes of Health Research.
Copyright © 2019 American Chemical Society.
- Mid-Cayman Rise
- buoyant plume