Director: James P. Ferris, Department of Chemistry and Chemical Biology
Associate Directors: Douglas C.B. Whittet, Department of Physics, Applied Physics, and Astronomy, and John W. Delano, Department of Earth and Atmospheric Sciences, and Department of Chemistry, University at Albany
Program Home Page: http://www.origins.rpi.edu
The New York Center for Studies on the Origins of Life involves faculty, postdoctorals, graduate students, and undergraduate students from Rensselaer Polytechnic Institute, the State University of New York at Albany, and the College of Saint Rose in education and research programs seeking to understand how life originated and evolved. Some of the major research areas are listed below.
Research Innovations and Initiatives
Sources of Organics on the Primitive Earth
Two major hypotheses for the origins of organics on the early Earth are being evaluated in the proposed research. First is the idea that the organic precursors to life were initially formed in the interstellar medium and, after processing during the formation of the solar system, were delivered to the Earth’s surface. The second hypothesis is that a reducing atmosphere formed by volcanic outgassing from a reduced mantle on the primitive Earth was the source of the organic precursors for life.
The organics present in the interstellar medium are investigated by ground-based and orbiting observatories in the two–25 microns wavelength range of the infrared by Douglas C.B. Whittet. These measurements have been made on the Infrared Space Observatory and on ground-based observatories in Hawaii and Chile. The high resolving power of these telescopes allows the detection of infrared frequencies characteristic of functional groups in organic molecules.
Shock Processing of Prebiotic Materials
Organic molecules formed in the interstellar medium are brought to the solar nebula in the icy coatings on dust grains. Wayne Roberge is simulating the processing of ices by the accretion shock where infalling dust enters the solar nebula, by shocks inside the solar nebula, and by external wind shocks where the bipolar outflow strikes infalling material. We find that nebular and accretion shocks can anneal the ices, greatly altering the ices’ capacity to retain volatile organics. The efficiency of annealing depends strongly on heliocentric distance, with important consequences for the relative volatile content of Jupiter family versus Kuiper Belt comets.
Reactions During Planet Formation
An important stage of organics processing is in the plantesimals created in the early stages of the planets, moons, asteroids, and comets. When radioactive decay heated these bodies, the frozen water in them liquefied. The reaction with water and the radiation from radioactive elements further altered the organics. Meteorites are fragments from asteroids which, together with comets, are believed to have brought these organics with them when they impacted the primitive Earth. These organics are believed to be the major source of starting materials for the origins of life. Michael J. Gaffey is using infrared spectroscopic measurements to investigate the structures of the organics on the outer belt asteroids.
The Oxidation State of the Earth’s Crust and Mantle
John W. Delano has determined the original oxidation state of ancient volcanic rocks up to 3.96 billion years ago using the geochemistries of Cr and V. The results of that investigation were published in late 2001 and indicate that high-temperature volcanic gases were not a likely source of chemically reduced gases at any time during the last 3.96 billion years. Work is proceeding in an effort to determine the Earth’s oxidation state of high-temperature volcanic gases prior to 3.96 billion years ago to see if they might have served as a source of gas species useful for the formation of prebiotic molecules.
Atmospheres of Titan and Jupiter
James P. Ferris is investigating through laboratory experiments the photochemical processes in the atmospheres of Titan and Jupiter. Using a flow chemical reactor where it is possible to irradiate the lowmixing ratios of atmospheric organics, the photochemical transformations in proposed primitive atmospheres are being investigated. With a flow reactor, it is possible to obtain sufficient amounts of reactants for their identification and quantification by nuclear magnetic resonance (NMR) and mass spectrometry.
The RNA World
Ribonucleic acid (RNA) was the most important biopolymer for the first life on Earth. The emphasis in this research is the prebiotic synthesis of RNA and the search for evidence of the RNA world in the introns of primitive life on Earth today.
Thioacids as Phosphorylating Reagents
William J. Hagan is investigating the thermal and photochemical formation of thioacids, which represent precursors of high-energy phosphate donors that might have promoted the phosphorylation of sugars, such as ribose. The latter is a possible step in the conversion of nucleosides to nucleotides, the building blocks of RNA.
Prebiotic RNA Synthesis
James P. Ferris is investigating the mineral-catalyzed formation of RNA from activated mononucleotides. The research will center on the origin of the RNA world, where RNA or RNA-like molecules have been proposed to be the most important biopolymers in the first life on Earth.
Search for Catalytic RNA Sequences
The third research emphasis is Sandra A. Nierzwicki-Bauer’s search for evidence of the postulated RNA world in the extant life on the Earth today. If RNA was the basis for the first life on Earth, vestiges of the sequences of ancient catalytic RNA in the RNA sequences of slow-growing, deep subsurface microorganisms may be found. The presence of the nucleotide sequence of the Group I intron, which catalyzes the splicing of RNA, is the object of the search in the introns of the subsurface bacteria.
The Impact History of the Primitive Earth
John W. Delano is determining the timing of large impact events on the Moon, and by analogy on the Earth, and the implications for the sustainability of life on the early Earth. Impact-produced glasses from three Apollo landing sites are being chemically and isotopically analyzed individually to determine the ages of impact events on the Moon. This dating makes it possible to determine whether the impact flux was simple (e.g., monotonic decrease through time) or complex (e.g., late cataclysm).
Earth and Environmental Sciences: J. Abrajano, M.J. Gaffey, B. Watson
Natural Sciences, the College of Saint Rose: W.J. Hagan
Biology: S.A. Nierzwicki-Bauer
Physics, Applied Physics, and Astronomy: W. Roberge