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Project Progress

During this period, we have continued our research on the stability of formate at elevated temperatures and in the presence of mineral surfaces. An autoclave system with a closed-loop sampling system is now operational. We are re-investigating the stability of formate as a function of temperature to address questions raised during the review of an earlier manuscript. Secondly, we have completed a theoretical modeling study of the thermodynamic driving force for dinitrogen reduction as a function of mineral-assemblage and temperature. A new direction of research that has been added to our effort is to investigate the effect of pyrite on the stability of biomolecules. In an earlier reporting period, we discovered that exposure of pyrite to water leads to the formation of hydrogen peroxide and OH radical, which was hitherto unknown. Illumination with visible light enhances the effect. Given the ubiquitous presence of pyrite on early Earth, its reaction with water may have been the dominant mechanism for the formation of OH radicals during the emergence of life. Our experimental work thus far has been focussed on the stability of ribonucleic acid (RNA). RNA decomposes rapidly in the presence of pyrite; however, encapsulation of RNA with lipid slows down the reaction. Alternatively, the decomposition reaction can be inhibited by coating pyrite with lipid. The results suggest a possible protective mechanism that could have been an important prerequisite for the origin of life.