Enantiomeric Excesses in Meteoritic Amino Acids
- 14 February 1997
- journal article
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 275 (5302), 951-955
- https://doi.org/10.1126/science.275.5302.951
Abstract
Gas chromatographic-mass spectral analyses of the four stereoisomers of 2-amino-2,3-dimethylpentanoic acid (DL-α-methylisoleucine and DL-α-methylalloisoleucine) obtained from the Murchison meteorite show that the L enantiomer occurs in excess (7.0 and 9.1%, respectively) in both of the enantiomeric pairs. Similar results were obtained for two other α-methyl amino acids, isovaline and α-methylnorvaline, although the α hydrogen analogs of these amino acids, α-amino- n -butyric acid and norvaline, were found to be racemates. With the exception of α-amino- n -butyric acid, these amino acids are either unknown or of limited occurrence in the biosphere. Because carbonaceous chondrites formed 4.5 billion years ago, the results are indicative of an asymmetric influence on organic chemical evolution before the origin of life.Keywords
This publication has 25 references indexed in Scilit:
- Amino acid cosmogeochemistryPhilosophical Transactions B, 1991
- The origin and amplification of biomolecular chiralityOrigins of Life and Evolution of Biospheres, 1991
- Unusual stable isotope ratios in amino acid and carboxylic acid extracts from the Murchison meteoriteNature, 1987
- Supernovae and lifeNature, 1983
- Amino acids of the murchison meteorite:Journal of Molecular Evolution, 1981
- α-Hydroxycarboxylic acids in the Murchison meteoriteNature, 1978
- Asymmetric photolysis of (RS)-leucine with circularly polarized ultraviolet lightJournal of the American Chemical Society, 1977
- Evidence for Extraterrestrial Amino-acids and Hydrocarbons in the Murchison MeteoriteNature, 1970
- Meteorites: Optical Activity in Organic MatterScience, 1966
- Optical Activity in Saponified Organic Matter Isolated from the Interior of the Orgueil MeteoriteNature, 1964