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Updated: Aug 9, 2026
08:14
Extraction of Non-Protein Amino Acids from Cyanobacteria for Liquid Chromatography-Tandem Mass Spectrometry Analysis
Published on: December 9, 2022
Nonprotein amino acids in the murchison meteorite
K A Kvenvolden1, J G Lawless, C Ponnamperuma
1Exobiology Division, Ames Research Center, NASA, Moffett Field, California 94305.
Summary
The Murchison meteorite contains twelve nonprotein amino acids, eight definitively identified. These extraterrestrial amino acids offer new evidence supporting chemical evolution theories.
Area of Science:
- Astrobiology
- Organic Geochemistry
- Cosmochemistry
Background:
- Meteorites are crucial for understanding the early solar system and the origins of life.
- The Murchison meteorite is a carbonaceous chondrite known for its rich organic content.
Purpose of the Study:
- To identify and confirm the presence of nonprotein amino acids in the Murchison meteorite.
- To investigate the extraterrestrial origin of these compounds.
- To assess their implications for the chemical evolution hypothesis.
Main Methods:
- Analysis of the Murchison meteorite's composition.
- Chromatographic and spectroscopic techniques for amino acid identification.
Main Results:
- Eight nonprotein amino acids were conclusively identified: N-methylglycine, beta-alanine, 2-methylalanine, alpha-amino-n-butyric acid, beta-amino-n-butyric acid, gamma-amino-n-butyric acid, isovaline, and pipecolic acid.
- Tentative evidence suggests the presence of four additional amino acids: N-methylalanine, N-ethylglycine, beta-aminoisobutyric acid, and norvaline.
Conclusions:
- The identified amino acids are of extraterrestrial origin.
- The presence of diverse nonprotein amino acids supports the hypothesis of prebiotic chemical evolution in space.
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