Hydrothermal Ecosystems

Evidence from the sequences of DNA suggests that contemporary bacteria and archaea may have descended from hyperthermophilic ancestors. This is because hyperthermophilic organisms cluster toward the base of the universal tree of life. Hyperthermophiles also interest us because they show a diverse array of physiologies for garnering carbon and energy from the interactions between water and hot rocks.

In this project we are studying the lipids of cultured hyperthermophiles and their cousins in hot springs and sub-sea vents systems in order to see if they have specific and diagnostic membrane lipids and to determine their relative abundances and likely physiologies in nature. Development of new High Precision Liquid Chromatography - Mass Spectormetry (HPLC-MS) methods for characterization of intact polar membrane lipids is an important aspect of the work. In collaboration with Everett Shock and D'Arcy Meyer-Dombard we are studying the biogeography of Aquificales in Yellowstone hot springs as a function of water chemistry.