2000 Annual Science Report
Pennsylvania State University Reporting | JUL 1999 – JUN 2000
Executive Summary
There is no executive summary for this team at this time.
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Hiroshi Ohmoto
NAI, ASTEP, ASTID, Exobiology -
TEAM Active Dates:
7/1998 - 10/2003 CAN 1 -
Members:
97 (See All) - Visit Team Page
Project Reports
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Paleomicrobiology and the Evolution of Metabolic Pathways in the Archaean Environment.
The project has two parts. First, ancient microfossils preserved in cherts are being studied with an ion microprobe allowing the analysis of the carbon isotopic composition of individual microfossils. Second, the process of carbon isotopic fractionation is being studied in a diverse set of microorganisms. Collectively, the results will constrain the carbon fixation biochemistry of ancient microorganisms.
ROADMAP OBJECTIVES: 4.0 5.0 6.0 7.0 -
Evolution of Atmospheric O2, Climate, and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations – Lee R. Kump 1
ROADMAP OBJECTIVES: 5.0 7.0 12.0 14.0 15.0 -
Timescale for the Early Evolution of Life on Earth: Molecular Evolutionary Approach – Hedges
The overall goal of research in this lab is to develop an accurate timescale for the evolution of life on Earth for comparison with Earth history (rise in oxygen, climate, plate tectonics, etc.). Such a synthesis will help to focus searches for life elsewhere. We use DNA and protein sequence data from the public databases and from sequences generated in the lab.
ROADMAP OBJECTIVES: 4.0 5.0 -
Timescale for the Early Evolution of Life on Earth: Molecular Evolutionary Approach – Nei
The main goal of the research in Task III is to develop statistical methods of estimating the times of origin of the major groups of organisms from molecular data and infer major events of early stages of evolution on Earth using a large amount of sequence data.
ROADMAP OBJECTIVES: 4.0 -
The Environment of Prebiotic Earth: Theoretical Approach
ROADMAP OBJECTIVES: 1.0 5.0 8.0 11.0 12.0 15.0 -
The Environment of Prebiotic Earth and the Origin of Life: Experimental Approach
Our group at SUNY-Stony Brook has focussed on two research projects: a) rate of CO hydration and stability of formate and b) reduction of dinitrogen to ammonia catalyzed by minerals.
ROADMAP OBJECTIVES: 1.0 2.0 3.0 5.0 7.0 12.0 -
The Prebiotic Chemistry of Hydrogen Cyanide
ROADMAP OBJECTIVES: 1.0 2.0 9.0 -
Enzymes of Ancient Metabolic Pathways – Ferry 1
ROADMAP OBJECTIVES: 2.0 -
Biochemistry of Physhrophilic Organisms
ROADMAP OBJECTIVES: 2.0 4.0 5.0 6.0 7.0 -
Microbe-Mineral Interactions
ROADMAP OBJECTIVES: 6.0 7.0 8.0 -
Whole Genome-Based Phylogenetic Analysis of Free-Living Microorganisms
ROADMAP OBJECTIVES: 4.0 5.0 -
Evolution of Atmospheric O2, Climate and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations. Causes and Consequences of the Diversification and Extinction of Metazoans: Field, Geochemical and Paleontological Investigations. – Katherine Freeman 1
ROADMAP OBJECTIVES: 1.0 4.0 5.0 15.0 -
Astrobiology Education and Public Outreach
ROADMAP OBJECTIVES: 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0 -
Task V: Neoproterozoic Variations in Carbon and Sulfur Cycling
ROADMAP OBJECTIVES: 12.0 14.0 -
Causes and Consequences of the Diversification and Extinction of Metasoans: Field, Geochemical and Paleontological Investigations – Mark E. Patzkowsky (Co-PI)
ROADMAP OBJECTIVES: 5.0 7.0 10.0 12.0 14.0 15.0 -
Evolution of Atmospheric O2, Climate, and the Terrestrial Biosphere/Causes and Consequences of the Diversification and Extinction of Metazoans – Rosemary C. Capo, Brian W. Stewart
ROADMAP OBJECTIVES: 5.0 6.0 7.0 10.0 11.0 12.0 14.0 15.0 -
“Alien Hunting” on What’s in the News
ROADMAP OBJECTIVES: 1.0 4.0 5.0 7.0 8.0 12.0 -
Enzymes of Ancient Metabolic Pathways – Ferry 2
The origin of life occurred sometime between 3.8 (end of heavy bombardment of Earth) and 3.5 (presence of microfossils in ancient sediments) billion years ago. In the absence of a volcanic source of methane and ammonia, the Earth’s atmosphere was a weakly reduced mixture of CO2 and N2 combined with lesser amounts of CO, H2, and reduced S gases (Kasting, 1993). The yield of complex organic matter through abiotic reactions under these conditions is believed to have been extremely low (Kasting, 1997). However, experiments by W@chtersh@user (1997) found that an aqueous slurry of coprecipitated NiS and FeS converted CO and CH3SH into acetic acid. This opened up the possibility of a chemoautotrophic origin of life in which early organisms could fix CO2 and CO enzymatically. Carbon monoxide dehydrogenase/ acetyl CoA synthase (CODH/ACS), the central enzyme of the reductive acetyl CoA pathway of many diverse modern-day anaerobes, fixes CO and CO2 non-photosynthetically. CODH/ACS utilizes substrates (CO, H2, and CO2) proposed to be present in the earth’s atmosphere around the time life originated. Its active site contains a NiFeS metal center, similar to that demonstrated in the experiments by W@chtersh@user
ROADMAP OBJECTIVES: None Selected -
Evolution of Atmospheric O2, Climate, and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations – Lee R. Kump 2
ROADMAP OBJECTIVES: 5.0 7.0 12.0 14.0 15.0 -
Evolution of Atmospheric O2, Climate, and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations – Lee R. Kump 3
ROADMAP OBJECTIVES: 5.0 7.0 12.0 14.0 15.0 -
Evolution of Atmospheric O2, Climate and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations. Causes and Consequences of the Diversification and Extinction of Metazoans: Field, Geochemical and Paleontological Investigations. – Ohmoto 1
ROADMAP OBJECTIVES: 1.0 4.0 5.0 15.0 -
Evolution of Atmospheric O2, Climate and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations. Causes and Consequences of the Diversification and Extinction of Metazoans: Field, Geochemical and Paleontological Investigations. – Ohmoto 2
ROADMAP OBJECTIVES: 1.0 4.0 5.0 15.0 -
Evolution of Atmospheric O2, Climate and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations. Causes and Consequences of the Diversification and Extinction of Metazoans: Field, Geochemical and Paleontological Investigations. – Ohmoto 3
ROADMAP OBJECTIVES: 1.0 4.0 5.0 15.0 -
Evolution of Atmospheric O2, Climate and the Terrestrial Biosphere: Approaches From Field-Oriented Geochemical Investigations. Causes and Consequences of the Diversification and Extinction of Metazoans: Field, Geochemical and Paleontological Investigations. – Katherine Freeman 2
ROADMAP OBJECTIVES: 1.0 4.0 5.0 15.0
Publications
- There are no publications for this team in the 2000 annual report.
2000 Teams
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Arizona State University
Carnegie Institution of Washington
Harvard University
Marine Biological Laboratory
NASA Ames Research Center
NASA Jet Propulsion Laboratory
NASA Johnson Space Center
Pennsylvania State University
Scripps Research Institute
University of California, Los Angeles
University of Colorado, Boulder