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2011 Annual Science Report

VPL at University of Washington Reporting  |  SEP 2010 – AUG 2011

Evolution of Metabolism

Project Summary

Our astrobiology research focus for VPL is to understand the evolution of different metabolic groups of microorganisms during the course of Earth’s history, and how the emergence of different metabolisms, such as methanogenesis, anoxic and oxygenic photosynthesis, and other anaerobic metabolisms that involve sulfur, metal, and nitrogen could effect the chemical composition of the atmosphere.

4 Institutions
3 Teams
9 Publications
0 Field Sites
Field Sites

Project Progress

Our astrobiology research focus for VPL is to understand the evolution of different metabolic groups of microorganisms during the course of Earth’s history, and how the emergence of different metabolisms, such as methanogenesis, anoxic and oxygenic photosynthesis, and other anaerobic metabolisms that involve sulfur, metal, and nitrogen could effect the chemical composition of the atmosphere. This research is framed by two overarching hypothesis that relate to the search for evidence of life on extra-solar planets: 1) Plate tectonics and associated hydrothermal activity, are key mechanisms for extracting lifesupporting volatiles and elements from rocks and creating diverse environmental settings; 2) The microbial ecosystems during the first 2-3 billion years on an Earth-like planet would be characterized by periods of extremely high densities of newly evolved specific metabolic groups of microorganism that can be referred to as “enrichment periods” since heterotrophic eukaryotic, the microbial predators, had not yet evolved. The enrichment periods would last until one or more key nutrients became limiting. We are testing these hypothesis through research on the microbial communities that exist in present day hydrothermal systems with particular emphasis on hydrogen and sulfur metabolism and nitrogen assimilation.

Three undergraduates (Florence van Tulder, Stephen Jensen, and Anne Doubleday) were involved in this project’s research.

  • PROJECT INVESTIGATORS:
    John Baross John Baross
    Co-Investigator
  • PROJECT MEMBERS:
    William Brazelton
    Postdoc

    Aaron Goldman
    Postdoc

    Rika Anderson
    Graduate Student

    Aditya Chopra
    Graduate Student

  • RELATED OBJECTIVES:
    Objective 5.1
    Environment-dependent, molecular evolution in microorganisms

    Objective 5.3
    Biochemical adaptation to extreme environments

    Objective 6.2
    Adaptation and evolution of life beyond Earth