Identification of chemoautotrophic microorganisms from a diffuse flow hydrothermal vent at EPR 9° North using 13C DNA Stable Isotope Probing and Catalyzed Activated Reporter Deposition-Fluorescence in situ Hybridization
Richberg, Kevin P.
MetadataShow full item record
LocationEast Pacific Rise
KeywordChemoautotrophic bacteria; Hydrothermal vents; Microbiology; Atlantis (Ship : 1996-) Cruise AT15-38
At deep‐sea hydrothermal vents chemolithoautotrophic microbes mediate the transfer of geothermal chemical energy to higher trophic levels. To better understand these underlying processes and the organisms catalyzing them, this research used DNA Stable Isotope Probing (SIP) combined with Catalyzed Activated Reporter Deposition‐Fluorescence in situ Hybridization (CARD‐FISH) to identify the microorganisms chemoautotrophically supporting the food web at a diffuse flow hydrothermal vent. Both anaerobic and aerobic shipboard incubations containing various augmented electron donor and acceptor species showed that Epsilonproteobacteria were the dominant chemoautotrophs with greater than 70% of the cells counted within the first 24 hours. 13C DNA SIP identified unique organisms not previously characterized from low temperature diffuse flow venting: green sulfur bacteria (Chlorobi‐like organisms) possibly utilizing photoautotrophy, aerobic Lutibacter litoralis‐like organisms growing under anaerobic conditions, and Epsilonproteobacterial Thioreductor sp. at temperatures above maximum known tolerances. This research illustrates both the promise and pitfalls of the SIP technique applied to hydrothermal systems, concluding that timing of the incubation experiments is the critical step in eliminating undesired 13C labeling. These results set the stage for a more thorough future examination of diffuse flow microorganisms by presenting interesting questions that second generation experiments could be designed to answer.
Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2010
Showing items related by title, author, creator and subject.
Humphris, Susan E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1976-10)Considerable geological and geophysical evidence now exists to support the hypothesis that seawater circulates through freshly intruded basalt at the mid-ocean ridges. As a consequence of this process, reactions between ...
Laboratory and field-based investigations of subsurface geochemical processes in seafloor hydrothermal systems Reeves, Eoghan P. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2010-06)This thesis presents the results of four discrete investigations into processes governing the organic and inorganic chemical composition of seafloor hydrothermal fluids in a variety of geologic settings. Though Chapters ...
Friedman, Carrie T. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1998-02)Stable sulfur isotopes (δ34S) and trace Co are analyzed in sulfide and sulfate minerals from six sample types collected from the TAG active mound, 26°N Mid-Atlantic Ridge. δ34S values range from 2.7 to 2O.9%, with sulfate ...