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Project Reports

• Untitled

  ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 4.1

• Identifying Microbial Life at Crustal Rock-Water Interfaces

  We are working to cultivate and characterize microorganisms which directly derive energy from reactions between mafic rocks and water. We are particularly targeting organisms that colonize the surfaces of the rocks during alteration. Thus we are also developing high-resolution chemical measurements capable of detecting reaction fronts and mineral by-products that form over time at the microbe-mineral interface.

  ROADMAP OBJECTIVES: 5.2 5.3 6.1 6.2 7.2

• DDF: Geomicrobiology of a Unique Ice-Sulfur Spring Ecosystem in the High Arctic

  A glacial, active sulfide spring environment at Borup Fiord Pass on Ellesmere Island in the Canadian High Arctic provides an excellent opportunity to study microbial life at a site that may be an analog to Europa, an ice-covered moon of Jupiter. During the past year we have collected samples from the extensive mats of sulfur-minerals that precipitate in discharge channels to identify the microbial communities hosted in the sulfur-ice, and to cultivate key key organisms mediating the oxidation of H2S to elemental sulfur.

  ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 7.1 7.2

• Origin of Multicellularity and Complex Land-Based Ecosystem

  80-90% of all land plants have mutualistic symbiotic associations with fungi where the fungal symbionts provide increased access to essential minerals and the fungal symbionts gain fixed carbon. We are characterizing the fungal symbionts in early lineages of land plants (over 300 million years old) that have a life cycle where one phase is above ground and photosynthetic and another phase is completely underground for as long as fifteen years. This subterranean phase in these poorly understood plants is completely dependant on a set of fungal symbionts to provide a source of fixed carbon. Establishing the identity of the fungal symbionts in these diverse underground plants is fundamental to understanding the broader co-evolutionary and ecological history of plant-fungal associations across the almost 500 million year history of land plants.

  ROADMAP OBJECTIVES: 4.2 5.2

• Understanding the Microbial Ecology of Geologically-Based Chemolithoautotrophic Communities

  The objective of this project is to investigate the potential for geologic systems to support the production of biomass by chemosynthetic microorganisms that use inorganic chemical reactions rather than sunlight as a source of metabolic energy. The research focuses on hydrothermal and subsurface environments, where reaction of water with rocks produces sources of chemical energy like those that might have occurred on the early Earth, or that might occur now on other planetary bodies like Mars and Europa. Numerical geochemical models of fluid-rock interaction have been developed to understand the types and amounts of chemical energy that are generated in modern geologic environments, and to explore how these chemical energy sources may have differed under the different conditions present on the early Earth or in extraterrestrial environments.

  ROADMAP OBJECTIVES: 2.1 4.1

• Microbial Diversity of a Hypersaline Microbial Mat

  The goal of this project is to survey the microbial life that comprises a hypersaline microbial mat at Guerrero Negro, Mexico using culture independent technology (ribosomal and other gene sequences). The results have expanded significantly our knowledge of microbial diversity, bacterial, archaeal and eucaryotic.

  ROADMAP OBJECTIVES: 3.2 3.3 5.1 5.2 5.3 7.2

• Biological Potential of Mars

  We are exploring the geochemical environment of the martian surface and near-surface regions, in order to understand constraints on habitability by microorganisms. In particular, we are examining the chemical reactions that take (or took) place in the geological environment, and calculating the amounts of energy that are released that could by used by microbes to support metabolism. As chemical energy is the likely source of energy to support martian organisms, its tabulation provides a strong constraint on the amount of life that could have or can be supported there. We can compare the results to similar calculations in terrestrial environments, in order to compare martian and terrestrial habitability.

  ROADMAP OBJECTIVES: 2.1 3.1

• Functional Genomics of Thioredoxins in Halobacterium Sp. NRC-1

  This project addresses the functions of an ancient protein family in Archaea that occupy extreme environments. Some of these proteins may play roles similar to those of comparable proteins in other living organisms, and thus may tell us about functions that evolved in the last universal common ancestor of life. Others may have evolved as the Archaea began to occupy specialized and often extreme environments. This project also addresses the emergence of proto-metabolic networks that supplied the precursors for the RNA World.

  ROADMAP OBJECTIVES: 3.1 3.2 5.1 5.3

• Bally Project

  ROADMAP OBJECTIVES: 1.1

• Star and Planet Formation

  ROADMAP OBJECTIVES: 1.1

• A Novel Route to New, Simpler, Self-Aminoacylating Ribozymes

  ROADMAP OBJECTIVES: None Selected

• Carbon Flow Between Organisms in Complex Communities

  ROADMAP OBJECTIVES: 4.2 5.2

• Sulfur Biogeochemistry of the Early Earth

  Sulfur is widespread in surface geochemical systems and is abundant in many rock types. It is present in volcanic gases and marine waters, and has served a key role in geobiological processes since the origin of life. Like other low atomic number elements, sulfur isotope ratios in various compounds usually follow predictable mass-dependent fractionation laws; these different mass-dependent isotope fractionations serve as powerful tracers for igneous, metamorphic, sedimentary, hydrothermal and biological processes. Mass-independent sulfur isotope fractionation is a short-wavelength photolytic effect that occurs in space, as well as in gas-phase reactions in atmospheres transparent to deep penetration by ultraviolet light. Crucial aspects of the chemical evolution of the early atmosphere — and the surface zone as a whole — can be followed by mass-independent sulfur isotopes in Archean metasedimentary rocks. Metabolic styles of organisms in response to global changes in surface redox over geologic time can also be traced with multiple S isotopes.

  We have concluded from our various studies over the last year and before to the very inception of the NAI node at Colorado, that all Archean sulfur minerals previously documented for their 34S/32S compositions warrant a comprehensive re-examination of their 32S, 33S, 34S (and 36S), sulfur isotope systematics.

  ROADMAP OBJECTIVES: 1.1 1.2 4.1 4.2 5.1 5.2 5.3 6.1 7.1 7.2

• Philosophical Problems in Astrobiology; Issues on the Origin of Life,

  My project is exploring philosophical issues in astrobiology. My central focus this year was on the origin of life: what is the proper level of analysis for a successful theory of the origin of life? Among other things, I compared and contrasted contemporary scientific theories of the origin of life in light of what philosophers of science have learned about the structure and justification of scientific theories.

  ROADMAP OBJECTIVES: 3.1 3.2 3.3 3.4 4.1 4.2

• Planet Formation and Dynamical Modeling

  ROADMAP OBJECTIVES: 1.1 3.1 6.2