A distinct and active bacterial community in cold oxygenated fluids circulating beneath the western flank of the Mid-Atlantic Ridge

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doi: 10.1038/srep22541
Author(s): Meyer, Julie L.; Jaekel, Ulrike; Tully, Benjamin J.; Glazer, Brian T.; Wheat, C. Geoffrey; Lin, Hueiting; Hsieh, Chih-Chiang; Cowen, James P.; Hulme, Samuel M.; Girguis, Peter R.; Huber, Julie A.
Author Affiliation(s): Primary:
University of Florida, Soil and Water Science Department, Woods Hole, MA, United States
Harvard University, United States
University of Southern California, United States
University of Hawaii at Manoa, United States
University of Alaska at Fairbanks, United States
Moss Landing Marine Laboratory, United States
Marine Biological Laboratory, United States
Volume Title: Scientific Reports
Source: Scientific Reports, 6(22541). Publisher: Nature Publishing Group, London, United Kingdom. ISSN: 2045-2322
Note: In English. 68 refs.; illus., incl. 4 tables, sketch map
Summary: The rock-hosted, oceanic crustal aquifer is one of the largest ecosystems on Earth, yet little is known about its indigenous microorganisms. Here we provide the first phylogenetic and functional description of an active microbial community residing in the cold oxic crustal aquifer. Using subseafloor observatories, we recovered crustal fluids and found that the geochemical composition is similar to bottom seawater, as are cell abundances. However, based on relative abundances and functional potential of key bacterial groups, the crustal fluid microbial community is heterogeneous and markedly distinct from seawater. Potential rates of autotrophy and heterotrophy in the crust exceeded those of seawater, especially at elevated temperatures (25°) and deeper in the crust. Together, these results reveal an active, distinct, and diverse bacterial community engaged in both heterotrophy and autotrophy in the oxygenated crustal aquifer, providing key insight into the role of microbial communities in the ubiquitous cold dark subseafloor biosphere.
Year of Publication: 2016
Research Program: IODP Integrated Ocean Drilling Program
ODP Ocean Drilling Program
Key Words: 02 Geochemistry; 22 Environmental Geology; Aquifers; Atlantic Ocean; Bacteria; Basaltic composition; Carbon; Carbon dioxide; Concentration; Crust; DNA; Discharge; Dissolved oxygen; Ecology; Ecosystems; Expedition 336; Experimental studies; Genetics; Geomicrobiology; Ground water; IODP Site U1382; IODP Site U1383; Integrated Ocean Drilling Program; Laboratory studies; Mid-Atlantic Ridge; Nitrogen; North Atlantic; Nucleic acids; Ocean Drilling Program; Oceanic crust; Organic carbon; Oxygen; PH; RNA; Sea water; Solutes; Trace elements
Coordinates: N224521 N224521 W0460453 W0460453
N224808 N224808 W0460310 W0460310
Record ID: 2016079189
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute.