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

Section of Organic Chemistry and Biochemistry, Technische Universität München, München, Bavaria, Germany
Science (Impact Factor: 33.61). 11/2006; 314(5799):630-2. DOI: 10.1126/science.1130895
Source: PubMed


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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    • "Contenders of the "primitive soup" scenario advocate that life may have arisen through chemoautotrophic processes occurring in oceanic depths in the vicinity of hydrothermal settings which would provide all necessary starting conditions [7]. In this "pioneer metabo‐ lism" scenario, the generation of homochiral metalloenzymes of extant organisms from inorganic transition metal precipitates (by chelation of alpha-hydroxyl and alpha-amino acids ligands) follows a stepwise evolution by autocatalytic feedback. "
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    Full-text · Chapter · May 2014
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    • "Life emerged about 3.5–4 billion years ago from amino acids and nucleotides, which were synthesized utilizing free radicalmediated reactions from simple reduced inorganic compounds (Line, 2002). Necessary energy was provided by cosmic and sun radiation and geo-volcanic processes (Cody et al., 2000; Huber and Wächtershäuser, 2006). "
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    Full-text · Article · Sep 2013 · Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association
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    • "The abiotic polymerization of amino acids may have been essential for the formation of primordial oligopeptides on early Earth (Oparin 1957). Many researchers have suggested that various amino acids could have formed on early Earth (Huber and Wächtershäuser 2006; Furukawa et al. 2009; Goldman et al. 2010) or could have been delivered to early Earth (Cronin and Moore 1971; Hennet et al. 1992; Marshall 1994; Bernstein et al. 2002; Pizzarello et al. 2003). The oligomerization of amino acids has been investigated in many studies that aimed to simulate environments, such as submarine hydrothermal systems and tidal flats, considered to be suitable for the origin of life (Lahav et al. 1978; Huber and Wächtershäuser 1998; Bujdák and Rode 1999; Imai et al. 1999; Kawamura et al. 2005; Cleaves et al. 2009). "
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