Isotopic analyses of amino acids from the Murchison meteorite

Journal Article · Thu Feb 28 23:00:00 EST 1991 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(91)90350-E· OSTI ID:6005065

Pizzarello, S; Cronin, J R ^[1]; Krishnamurthy, R V; Epstein, S ^[2]

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1. Arizona State Univ., Tempe (United States)
2. California Inst. of Tech., Pasadena, CA (United States)

Previous isotopic analyses of the total amino acids of the Murchison meteorite showed these compounds to be substantially enriched in {sup 2}H, {sup 13}C, and {sup 15}N relative to terrestrial organic matter. These analyses have been repeated ({sup 2}H, {sup 13}C) with inclusion of an ultrafiltration step to exclude the possibility that a fine particulate contaminant carried the isotopic excesses observed in the previous work. In addition, the meteorite amino acids were chromatographically separated to rule out the possibility that the isotopic enrichment of the meteorite extract could reside in basic compounds other than amino acids. The results indicate that the Murchison amino acids are truly isotopically unusual, that the isotopic excesses reside in at least several different amino acids, and that the isotopic contents of some of these amino acids reach values of about +40{per thousand} ({delta}{sup 13}C) and +2,500{per thousand} ({delta}D). If it is assumed that the high deuterium content of the meteroite {alpha}-amino acids is a result of the synthesis of their molecular precursors by low temperature ion-molecule reactions in an interstellar cloud, their formation by aqueous phase Strecker reactions in the parent body is consistent with their general characteristics and with known parent body processes.

• OSTI ID: 6005065
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Journal Name: Geochimica et Cosmochimica Acta; (United States) Vol. 55:3; ISSN GCACA; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AMINO ACIDS
CARBON 13
CARBON ISOTOPES
CARBOXYLIC ACIDS
CHARGED PARTICLES
CHEMICAL COMPOSITION
COMPARATIVE EVALUATIONS
EVALUATION
EVEN-ODD NUCLEI
HYDROGEN IONS
IONS
ISOTOPE RATIO
ISOTOPES
LIGHT NUCLEI
METEORITES
NITROGEN 15
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORIGIN
PETROGENESIS
STABLE ISOTOPES