Related Experiment Video
Updated: Jul 11, 2026
08:21
Curation of Computational Chemical Libraries Demonstrated with Alpha-Amino Acids
Published on: April 13, 2022
Amino acids indigenous to the murray meteorite
Science (New York, N.Y.)
|August 13, 1971
Summary
Analysis of the Murray meteorite revealed 17 amino acids, with many showing equal D/L isomers and non-protein origins. These findings support an extraterrestrial origin for these organic compounds.
Area of Science:
- Astrobiology
- Cosmochemistry
- Organic Geochemistry
Background:
- Carbonaceous chondrites are primitive meteorites offering insights into early solar system chemistry.
- The presence and chirality of amino acids in meteorites can indicate their origin.
Purpose of the Study:
- To analyze the amino acid composition of the Murray meteorite, a type II carbonaceous chondrite.
- To investigate the isomeric distribution (D and L forms) of identified amino acids.
- To determine if the amino acids are consistent with an extraterrestrial origin.
Main Methods:
- Chemical analysis of meteorite samples.
- Identification and quantification of amino acids.
- Chiral analysis to determine D and L isomer ratios.
Main Results:
- Seventeen different amino acids were identified in the Murray meteorite.
- For seven amino acids, nearly equal amounts of D and L isomers were detected.
- Eleven of the identified amino acids are not typically found in biological proteins.
Conclusions:
- The observed amino acid composition and chirality in the Murray meteorite suggest an extraterrestrial origin.
- These findings are comparable to those from other carbonaceous chondrites, like the Murchison meteorite.
- The study supports the hypothesis that organic molecules essential for life can form in space.
Related Concept Videos
01:15Mass Spectrometry of Amines
In mass spectroscopy, amines undergo fragmentation to give parent ions with odd molecule weights. This observed mass spectrum follows the nitrogen rule; a molecule with an odd number of nitrogen atoms produces a molecular ion with an odd molecular weight. Amines undergo fragmentation through α cleavage, producing nitrogen-containing cations—iminium ions—and alkyl radicals. Mass spectra of aromatic and cyclic aliphatic amines exhibit strong molecular ion peaks, but acyclic aliphatic amines show...
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
01:18Amino Acid Catabolism
Microorganisms rely on proteins as an essential carbon and energy source, particularly in environments with limited polysaccharides or lipids. However, proteins are too large to cross the plasma membrane unaided, necessitating enzymatic degradation. Microbes secrete extracellular proteases and peptidases that hydrolyze proteins into peptides, which can then be transported across the membrane. Once inside the cell, intracellular proteases degrade these peptides into free amino acids, which...
03:42Amino acids
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
01:19NMR Spectroscopy Of Amines
In proton NMR spectroscopy, primary amines and secondary amines showcase their N–H protons as a broad signal in the chemical shift range between δ 0.5 and 5 ppm. The exact position in this range depends on several factors, including sample concentration, hydrogen bonding, and the type of solvent used. Since amine protons undergo fast proton exchange in solution, the protons are labile and therefore do not participate in any splitting with adjacent protons. Thus, the observed peak is broad and...
01:29Amino Acid Biosynthetic Pathways
Amino acid biosynthesis is essential for cell growth, protein synthesis, and metabolic regulation. Cells generate essential and non-essential amino acids from metabolic intermediates to sustain vital biological functions. These intermediates originate from key metabolic pathways: glycolysis, the tricarboxylic acid (TCA) cycle, and the pentose phosphate pathway. Important precursors include α-ketoglutarate, pyruvate, oxaloacetate, phosphoenolpyruvate, and erythrose-4-phosphate, which provide...