Miller–Urey Spark‐Discharge Experiments in the Deuterium World

Abstract

We designed and conducted as eries of primordialsoup Miller-Urey style experiments with deuterated gases and reagents to compare the spark-discharge products of a" deuterated world" with the standardreaction in the "hydrogenated world". While the deuteration of the system has little effect on the distribution of amino acid products,significant differences are seen in other regions of the product-space.Not only do we observe about 120 new species,w ea lso see significant differences in their distribution if the two hydrogen isotope worlds are compared. Several isotopologue matches can be identified in both, but alarge proportion of products have no equivalent in the corresponding isotope world with ca. 43 new species in the Dworld and ca. 39 new species in the Hworld. This shows that isotopic exchange (the addition of only one neutron) may lead to significant additional complexity in chemical space under otherwise identical reaction conditions.

Environmental Control Programs the Emergence of Distinct Product Ensembles from Unconstrained Chemical Reaction Networks

“…In recent work, we 9 and others 27,28 have begun to take a more open approach to complex mixtures; instead of avoiding complexity, we embrace it, and use modern analytical tools to observe otherwisehidden patterns in complex synthetic systems. Here, we hypothesise that while unconstrained multicomponent reactions do produce a mess, they may be steered to different areas of product space.…”

“…For this we chose a classic "Primordial Soup": the products of the Miller-Urey type spark discharge experiment ("SD Mix", hereafter). 11,39 Starting from a simple mixture of gases (H2, CH4, NH3) and refluxing water, with the gases passing through a high energy spark discharge between two tungsten electrodes, 9 this experiment produces a notoriously complex product mixture. Since SD Mix is known to contain a very wide variety of species, including carboxylic acids, alcohols, aromatic species, and amino acids, 11,39 the possibility of forming condensation products is clear.…”

“…As researchers interested in how functional ordered chemical systems might be produced from an inorganic world, to ultimately form biological/life-like systems, 4,5 we cannot avoid heterogeneity. 3,[6][7][8][9] In recent decades, however, most chemists researching life-like systems 10 have moved from exploring high-energy unconstrained 'soup' reactions, 11,12 to examining the intricate mechanisms required for abiotic synthesis of nucleotides, 13 polynucleotides, [14][15][16] and peptides, [17][18][19][20] and on towards the assembly of protocells, [21][22][23] enzyme-mediated systems, 24 and exploration of autocatalysis. 25,26 This transition arose from the expectation that unconstrained multicomponent reactions would undergo combinatorial explosion.…”

Experimental Approaches for Testing the Hypothesis of the Emergence of Life at Submarine Alkaline Vents

“…The Miller–Urey experiment was considered to be, as mentioned, a landmark in the experimental approaches performed in the context of the OoL studies. It was also considered to be the establishment of prebiotic chemistry as a field of research [ 1 , 31 ]. In this experiment, the early ocean–atmosphere system was simulated based on the conditions proposed by Urey (1952) [ 32 ].…”

“…Thus, it comprised an apparatus in which a highly reducing atmosphere under 1.5 bar—consisting of CH 4 , NH 3 , H 2 and water vapor—was submitted to electric sparks under the potential of 6 × 10 4 V for a week [ 1 ]. As a result, organic compounds, amino acids among them, were detected in the solution [ 9 , 31 , 33 ]. Revisions were made in the conditions of the experiment due to new discoveries about prebiotic Earth conditions, mainly in the Hadean atmosphere.…”