Research Abstract:
My group’s research is focused on the microbiology and geochemistry of hydrothermal environments. The overarching goal is to better understand the role of thermophilic microbial communities in high temperature systems and the geochemical constraints on metabolic strategies pursued by archaea and bacteria in thermal environments. Our research includes field, laboratory, and computational components.
We sample and analyze waters, gases, and sediments in the hydrothermal systems of the Aeolian Islands (Italy), Yellowstone National Park, and Ambitle Island (Papua New Guinea). Research projects in the Aeolian Islands and at Yellowstone include determining the microbial community structure in hydrothermal sediments and waters, investigating the in situ metabolisms at these sites, quantifying the energetics for chemotrophs, measuring the concentration and distribution of aqueous organic compounds in hydrothermal fluids, using geochemistry to design site-specific growth media for thermophiles, and isolating and characterizing novel archaea and bacteria. A project in Papua New Guinea seeks to investigate the ecosystem response to elevated arsenic concentrations in shallow marine hydrothermal vents. We are particularly interested in microbes that obtain energy by oxidizing As(III) or reducing As(V). This study is a collaborative effort with geochemists, marine scientists, and biologists from the University of South Florida.
New research projects include laboratory growth studies of hyperthermophile metabolism in the context of reaction energetics, and astrobiological research targeting potentially habitable zones on Mars.
Selected Publications:
Rusch A, Amend JP. Functional characterization of the microbial community in geothermally heated marine sediments. Microbial Ecology 2008 55:723-736.
Rogers KL, Amend JP, Gurrieri S. Temporal changes in fluid chemistry and energy profiles in the Vulcano Island hydrothermal system. Astrobiology 2007 7:905-932.
Pichler T, Price RE, Amend JP, et al. A natural laboratory to study arsenic geobiocomplexity. EOS 2006 87:221-226.
Rogers KL, Amend JP. Archaeal diversity and geochemical energy yields in a geothermal well on Vulcano Island, Italy. Geobiology 2005 3:319-332.
McCollom TM, Amend JP. A thermodynamic assessment of energy requirements for biomass synthesis by chemolithoautotrophic microorganisms in oxic and anoxic environments. Geobiology 2005 3:135-144.
Last Updated: 08/17/2009 |