Volcano gas, amino acids make peptides

In an experiment that closely simulated conditions likely to have been present in the primitive Earth, bubbling simple volcanic gas into a solution containing amino acids brought about the formation of peptides, according to a study published this week in Science. The study, critics agree, is a major step forward in deciphering the chemistry of the transformation of monomers into polymers in the early Earth.

Luke Leman, of the Scripps Research Institute, and his colleagues added carbonyl sulfide into air-free aqueous solutions that contained L-phenylalanine, and obtained dipeptides and tripeptides in yields of up to 80% at room temperature. Mixtures of other amino acids combined into peptides as well.

Amino acids, and other monomers, can be obtained under prebiotic experimental conditions, and have also been found in meteorites, comets, and interplanetary dust particles hitting the Earth, said M. Reza Gadhiri, also from Scripps, and a co-author of the paper. "We ...