Here are the main points—but you should read the whole thing.
- Primordial catalysts were probably not proteins nor RNA
- First Energy Source Likely Involved Proton Gradients
- Knowledge of New Bacterial Kingdoms Downplays Role of Fermentation In First Cells
While Miller and his fellow “soupists” blazed the initial paths in origins of life research, a startling new era dawned in the 80s with the discovery of potential life-sustaining factories in the most unlikely environments. The finding that life thrives in deep hydrothermal vents opened a whole new chapter in the field, again avowedly chemical. Black smoker chimneys located miles beneath the ocean have for millions of years been orchestrating a tumultuous union of hot, metal-rich, acidic chemicals arising from volcanic vents with cool alkaline waters. The unholy meeting of these two chemical opposites leads to a violent precipitation of minerals including the silicate mineral olivine, one of the most ubiquitous components of our planet’s rocky landscape. The precipitation of these minerals results in chimney like structures that can be miles high. The convecting thermal currents in these chimneys provide an abundant source of life’s sine qua non – energy. The metals can act as catalysts for simple reactions which involve sulfur, carbon monoxide and water. In recent years, because of the sheer energy hidden inside them, their capacity to catalyze key reactions like the Krebs cycle and concentrate reactants and products in microscopic pores and the uncanny resemblance of some of the iron and sulfur compounds to crucial iron-sulfur cores found in proteins, these mighty smokers have been considered by many scientists to precede or at least accompany the origin of life on the surface. Prominent among the “smokers” are scientists like Nick Lane and the patent attorney Günter Wächterhäuser who moonlights in the field as a “hobby”. These theories provide the “metabolism first” counterpart to the “replication first” camp. Together they may account for both genetic inheritance and chemical metabolism.It doesn't matter whether you're a soupist or a smoker but you'd better be aware of the controversy. Too many scientists think that the primordial soup is still the best, and only, game in town in spite of its severe problems.
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