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Project Reports

• Biomimetic Cluster Synthesis: Bridging the Structure and Reactivity of Biotic and Abiotic Iron-Sulfur Motifs

  Synthetic approaches are being utilized to bridge the gap between Fe-S minerals and highly evolved biological Fe-S metalloenzymes. These studies are focusing on organic template (protein) mediated cluster assembly (biomineralization), probing properties of synthetic clusters, both as homogeneous and heterogeneous catalysts, investigating the impact of size scale on the properties of synthetic Fe-S clusters, and computational modeling of the structure and catalytic properties of synthetic Fe-S nanoparticles in the 5-50 nm range.

  ROADMAP OBJECTIVES: 3.1 3.2 3.3 3.4 7.1 7.2

• Early Metabolic Pathways

  The project is aimed at characterizing the emergence of functional proteins and their early evolution leading to the formation of primitive metabolism in ancestors of contemporary cells. Through a combination of molecular biology and computer modeling we investigate the origins of both water-soluble enzymes and membrane proteins that mediate transport of small molecules and ions across cell walls.

  ROADMAP OBJECTIVES: 3.2 3.4

• 4. Prebiotic Molecular Selection and Organization

  ROADMAP OBJECTIVES: 3.1 3.2 3.4 4.1 7.1

• Origin of Life and Catalysis – Philosophical Considerations

  Our goal is to provide a solid philosophical foundation for the ABRC research program. To achieve this goal, we have several sub-goals like helping the students to develop their position as a group regarding a viable account for the metabolism-first theory, examining some methodological assumptions of the current astrobiological community, and finally propagating the information learned in our group to a larger community by offering courses on the origin of life.

  ROADMAP OBJECTIVES: 3.1 3.2 3.3 3.4 4.2

• Probing the Structure and Nitrogen Reduction Activity of Iron-Sulfur Minerals

  Fe-S compounds are common in both biological and geological systems. The adaptation of Fe-S clusters from the abiotic world to the biological world may have been an early event in the development of life on Earth and possibly a common feature of life elsewhere in the universe. The Iron-sulfur mineral thrust of the ABRC is focused on examining the structure and reactivity of FeS minerals using nitrogen fixation as a model reaction.

  ROADMAP OBJECTIVES: 3.1 3.2 3.3 3.4 7.1 7.2

• Prebiotic Organics From Space

  This project has three components, all aimed to better our understanding of the connection between chemistry in space and the origin of life on Earth and possibly other worlds. Our approach is to trace the formation and evolution of compounds in space, with particular emphasis on identifying those that are interesting from a prebiotic perspective, and understand their possible roles in the origin of life on habitable worlds. We do this by first measuring the spectra and chemistry of materials under simulated space conditions in the laboratory. We then use these results to interpret astronomical observations made with ground-based and orbiting telescopes. We also carry out experiments on simulated extraterrestrial materials to analyze extraterrestrial samples returned by NASA missions or that fall to Earth in as meteorites.

  ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.4 4.3 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

• The Diversity of the Original Prebiotic Soup: Re-Analyzing the Original Miller-Urey Spark Discharge Experiments

  Recently obtained samples from some of the original Stanley Miller spark discharge experiments have been reanalyzed using High Pressure Liquid Chromatography-Flame Detection and Liquid Chromatography-Flame Detection/Time of Flight-Mass Spectrometry in order to identify lesser constituents that would have been undetectable by analytical techniques 50 years ago. Results show the presence of several isoforms of aminobutyric acid, as well as several serine species, isomers of threonine, isovaline, valine, phenylalanine, ornithine, adipic acid, ethanolamine and other methylated and hydroxylated amino acids. Diversity and yield increased in experiments utilizing an aspirating device to increase the gas flow rates; this could be applied as a simulation of prebiotic chemistry during a volcanic eruption. The variety of products formed in these experiments is significantly greater than previously published and mimic the assortment of compounds detected in Murchison and CM meteorites.

  ROADMAP OBJECTIVES: 2.1 3.1 3.2 3.4 4.1 4.2 5.1 6.2 7.1 7.2