alpha-Hydroxy and alpha-amino acids under possible Hadean, volcanic origin-of-life conditions.

Section of Organic Chemistry and Biochemistry, Technische Universität München, München, Bavaria, Germany
Science (Impact Factor: 31.48). 11/2006; 314(5799):630-2. DOI: 10.1126/science.1130895
Source: PubMed

ABSTRACT To test the theory of a chemoautotrophic origin of life in a volcanic, hydrothermal setting, we explored mechanisms for the buildup of bio-organic compounds by carbon fixation on catalytic transition metal precipitates. We report the carbon monoxide-dependent formation of carbon-fixation products, including an ordered series of alpha-hydroxy and alpha-amino acids of the general formula R-CHA-COOH (where R is H, CH3,C2H5,orHOCH2 and A is OH or NH2) by carbon fixation at 80 degrees to 120 degrees C, catalyzed by nickel or nickel,iron precipitates with carbonyl, cyano, and methylthio ligands as carbon sources, with or without sulfido ligands. Calcium or magnesium hydroxide was added as a pH buffer. The results narrow the gap between biochemistry and volcanic geochemistry and open a new gateway for the exploration of a volcanic, hydrothermal origin of life.

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