2013 Annual Science Report
Rensselaer Polytechnic Institute Reporting | SEP 2012 – AUG 2013
Project 8: Microenvironmental Influences on Prebiotic Synthesis
Before biotic, i.e., “biologically-derived” pathways for the formation of essential biological molecules such as RNA, DNA and proteins could commence, abiotic pathways were needed to form the molecules that were the basis for the earliest life. Much research has been done on possible non-biological routes to synthesis of RNA, thought by many to be the best candidate or model for the emergence of life. Our work focuses on possible physicochemical microenvironments and processes on early earth that could have influenced and even directed or templated the formation of RNA or its predecessors.
Our research in the past year has focused on RNA polymerization under conditions commensurate with current understanding of the early earth environment. RNA polymerization reactions are being conducted in several plausible systems including (1) simulated, iron-containing hydrothermal “chimneys” (this project was initiated through a NAI Astrobiology Program Travel Award “Effects of Catalytic Iron-Containing Minerals on RNA Synthesis” to Dr. Laurie Barge at JPL, NAI Icy Worlds team, to visit our lab and work with graduate student Bradley Burcar), (2) clays that are infused with small molecules such as amino acids or “molecular midwife” compounds, and (3) solutions of monomeric nucleosides and nucleotides with and without clay. In the latter case, our focus is on the effects of reversible nucleoside and nucleotide self-assembly to create liquid crystalline phases that will affect the microenvironments of the RNA polymerization reactions and the availability of the monomeric nucleosides for RNA polymerization. A second focus is on the analysis of RNA polymerization products using MALDI-mass spectrometry. Detailed studies of these mass spectra have revealed potential errors and ambiguities in the interpretation of the results that provide alternate explanations for recent literature reports that montmorillonite-catalyzed reactions may generate much larger products than previously reported [Zagorevskii DV, Aldersley MF, Ferris, JP (2006) MALDI Analysis of Oligonucleotides Directly from Montmorillonite. J Am Soc Mass Spectrom 17:1265–1270], and that abiotic polymerization of cyclic monophosphate nucleotides may occur in the absence of a catalyst [Costanzo G, Pino S, Botta G, Saladino R, Di Mauro E (2011) May Cyclic Nucleotides Be a Source for Abiotic RNA Synthesis? Orig Life Evol Biosph 41:559-562, Costanzo G, Saladino R, Botta G, Giorgi A, Scipioni A, Pino S, Di Mauro E (2012) Generation of RNA Molecules by a Base-Catalysed Click-Like Reaction. ChemBioChem 13:999-1008].
PROJECT INVESTIGATORS:Linda McGown
PROJECT MEMBERS:Laura Barge
RELATED OBJECTIVES:Objective 3.1
Sources of prebiotic materials and catalysts
Origins and evolution of functional biomolecules