This proposal most directly relates to the planetary science/exobiology goals that seek to understand the origin of life. IT ties as well to the broader exobiology program in the benner lab, which…

This is a research grant awarded by the National Aeronautics and Space Administration (NASA) to the Foundation For Applied Molecular Evolution, Inc., a non-profit research organization, to support work related to understanding the origins of life. The $585,961 grant supports experimental research on the "RNA First" model for the prebiotic formation of RNA, building on the "Discontinuous Synthesis Model" (DSM) and exploring challenges that must be resolved for the DSM to be accepted as a potential solution to the origins of life puzzle. The research aims to advance knowledge in key areas such as the adsorption and stabilization of RNA by various minerals, the role of volcanic sulfur dioxide in producing stable carbohydrate reservoirs, and the use of molybdenum to address "tar" issues in carbohydrate prebiotic chemistry. The grant does not have a set-aside designation and runs from August 2018 to July 2021.

This proposal most directly relates to the planetary science/exobiology goals that seek to understand the origin of life. IT ties as well to the broader exobiology program in the benner lab, which exploits models for origins to guide the search for darwinism in the solar system, constructs "alien" genetic systems to understand the range of possible biosignatures, and models the evolution of terran life working back in time to define an "end goal" for origins work. Thus, this work will have impact beyond simply elaborating an important model for the origins of life. Indeed, some of chemistry that we develop could be occurring on mars today. The experimental work is organized around the "RNA first" model for the origin of darwinism. IT builds on the "discontinuous synthesis model" (DSM) for the prebiotic formation of RNA. The DSM, in turn, is set in an explicit model for early planetary history, including a model for forming the "late veneer", models for the redox potentials of the mantle and atmosphere at the time when life emerged, and models for minerals available in such environments. We then identify individual challenges remaining in the DSM that must be resolved before IT can be accepted by the community as one possible solution to the "origins" conundrum. We then propose experiments, with alternatives to manage pitfalls, to resolve them. The work benefits from seed money provided by the templeton foundation, which (together with NASA support) led to multiple discoveries that will be developed. We discovered: (1) a spectrum of carbonate, sulfate, and silicate minerals that adsorb and stabilize RNA, often with a periodic table trend; one chiral mineral (quartz) even distinguishes homochiral d-RNA and l-RNA. This discovery will be developed by studying other chiral minerals and mineral surfaces, quantitatively comparing RNA binding by competition experiments, and moving from binary minerals to ternary minerals in realistically complex GEO-environments. (2) volcanic sulfur dioxide provides a simple way to get stable reservoirs of formaldehyde and other simple carbohydrates; these complement borate-carbohydrate minerals that allow advanced species to accumulate in useful amounts. This work will quantitate equilibrium constants to assess the value of sulfonates in managing "TAR" problems in carbohydrate prebiotic chemistry, assess their compatibility with other mineral species in realistic GEO-environments, and possibly rescue proposals (e.g. of sutherland) that require large amounts of these. (3) we hypothesize that molybdenum (+6) can complete the management of the "TAR" problem for carbohydrates; experiments now show that IT was available in the hadean. We will assess its performance in realistically complex mineral environments, determine its compatibility with phosphate, borate, and other mineral anions, and study its redox interaction with ferrous, sulfite, and other reduced species. (4) mineral-based processes using the krishnamurthy polyphosphate amide allow formation of glycosidic bonds of nucleoside phosphates in desert environments; borate-mediated rearrangements give nucleoside 5'-phosphates. We will assess three approaches to make activated nucleoside phosphates available for oligomeric RNA formation, including alternative oxidation states of sulfur. We will then do "big picture" experiments, illustrating how loeb's "silent discharge" in a post-veneer atmosphere can produce sufficient HCN, hncnh, and other products that, if rained into physical rock containing olivine, tourmaline, and other mineral species, generate an effluent that can lead to the formation of RNA after draining into a dry space under a CO2 atmosphere. Consistent with a NASA budget, this will start with a synthetic effluent with nucleobases likely made in geothermal regions exposed to formamide, cyanamide, and cyanoacetylene, with RNA products stabilized by absorption on minerals.