The scientists reconstructed the conditions of this prebiotic sea based on the composition of various early sediments described in the scientific literature. The different metabolites were incubated at high temperatures (50-90oC) similar to what might be expected close to a hydrothermal vent of an oceanic volcano, a temperature that would not support the activity of conventional protein enzymes. The chemical products were separated and analyzed by liquid chromatography tandem mass spectrometry.
Some of the observed reactions could also take place in water but were accelerated by the presence of metals that served as catalysts. "In the presence of iron and other compounds found in the oceanic sediments, 29 metabolic-like chemical reactions were observed, including those that produce some of the essential chemicals of metabolism, for example precursors of the building blocks of proteins or RNA," says Ralser. "These results indicate that the basic architecture of the modern metabolic network could have originated from the chemical and physical constraints that existed on the prebiotic Earth."
The detection of one of the metabolites, ribose 5-phosphate, in the reaction mixtures is particularly noteworthy. Its av
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European Molecular Biology Organization