In vitro growth of iron sulphide chimneys: possible culture chambers for origin‐of‐life experiments

Abstract

Iron monosulphide globules and tubes grown in the laboratory have similar morphologies to the fossil pyrite botryoids and chimneys found in the Silvermines exhalative sedimentary ore-body of Carboniferous age in Ireland. We envisage analogous fine structures growing at hot springs (100-200°C) in the earliest oceans as having provided the culture chambers and flow reactors for life to originate by phosphorylation and growth of organic molecules on the iron sulphide surfaces. Such sulphide structures grown in the laboratory could be used in origin-of-life experiments. We: a hypothesis, System. Appl. Microbiof., 10,207-210. Wachtershauser G. (1988b) Before enzymes and templates: theory of surface metabolism, Minobiol. Reviews, 52,452-484. Wachtershauser G. (1988c) Deutsches Patentamt 3812158, FRG. Wark E.E. and Wark I.W. (1935) The physical chemistry of flotation. VI the adsorption of amines by sulfide minerals, J. Phys. Chem., 39,1021-1030. Windley B.F., S i p s o n P.R. and Muir M.D. (1984) The role of atmospheric evolution in Precambrian metallogenesis, Fortschr. Miner., 62, 99,712-720. 253-267.

Peptide and RNA contributions to iron–sulphur chemical gardens as life's first inorganic compartments, catalysts, capacitors and condensers

“…The ultimate reduction or waste product was probably initially acetate [12][13][14][15], and the womb or omphalos of life a chemical garden-like precipitate over a submarine alkaline spring, especially where it vented into the acidulous, iron-bearing Hadean Ocean [16][17][18]. Much as predicted, a comparable spring-the so-called Lost City-was discovered in the North Atlantic in 1999 [16,19,20].…”

“…In contrast, where alkaline hydrothermal fluids at off-axis vents traversed sulphide accumulations, sulphide itself would likely have been mobilized and upon interaction with dissolved metal ions in the ocean, precipitated with them to form inorganic chimneys [16,38]. This notion is based on the discovery of fossilized pyrite structures at what were relatively shallow water vent locations and the known reactivity of sulphide with transition metals (in particular, iron) [29,30,39].…”

“…Other than the fossilized remnants of pyrite chimneys and an early report of the formation of such chimneys in vitro [2,16,30], little is known as to the properties of chimney formation as it would have occurred on the early Earth. Given the existence of alkaline hydrothermal chimneys as probable localities for a geochemically and electrochemically driven emergence of life, they are urgent targets for research into the processes that govern their formation, as well as for empirical testing of their ability to act as flow-through reactors and culture chambers for chemical interconversions leading at least to the onset of metabolism [16].…”

“…Thus, one could imagine how chemical gradients could be sustained and how reactions and molecular sequestration in a relatively lowtemperature environment insulated from the turbulent conditions of the surface could operate [2]. On the early ocean floor, locations would have existed that channelled the exergonic products of serpentinization, locations where reduced minerals (mafic and ultramafic crust) were oxidized, and water and carbon dioxide were concomitantly reduced to hydrogen and methane [16,40]. From a chemical perspective, off-axis spring localities, where low-potential (reducing) electronic species are exhaled from the Earth, may have provided a portion of the necessary energy required for early hydrogenation reactions that were crucial in the accumulation of biologically relevant molecules and electronic equivalents at the origin of life [41,42].…”

“…With these examples of hydrothermal chimneys to go on, smaller, fossil specimens-comprising pyrite (FeS 2 )-were soon discovered, although in mineral sulphide deposits generated at lower temperature [16,[29][30][31][32][33]. Since these discoveries, active submarine hydrothermal vents have been found to exist with a wide array of attributes and can be divided into the high-temperature acidic 'Black Smokers' and the cooler, alkaline 'off-axis' systems, the Lost City type [20].…”