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Hiroshi Naraoka - One of the best experts on this subject based on the ideXlab platform.
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a new family of extraterrestrial amino acids in the murchison Meteorite
Scientific Reports, 2017Co-Authors: Toshiki Koga, Hiroshi NaraokaAbstract:The occurrence of extraterrestrial organic compounds is a key for understanding prebiotic organic synthesis in the universe. In particular, amino acids have been studied in carbonaceous Meteorites for almost 50 years. Here we report ten new amino acids identified in the Murchison Meteorite, including a new family of nine hydroxy amino acids. The discovery of mostly C3 and C4 structural isomers of hydroxy amino acids provides insight into the mechanisms of extraterrestrial synthesis of organic compounds. A complementary experiment suggests that these compounds could be produced from aldehydes and ammonia on the Meteorite Parent Body. This study indicates that the meteoritic amino acids could be synthesized by mechanisms in addition to the Strecker reaction, which has been proposed to be the main synthetic pathway to produce amino acids.
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carbon isotopic composition of acetic acid generated by hydrous pyrolysis of macromolecular organic matter from the murchison Meteorite
Meteoritics & Planetary Science, 2006Co-Authors: Yasuhiro Oba, Hiroshi NaraokaAbstract:Low molecular weight monocarboxylic acids, including acetic acid, are some of the most abundant organic compounds in carbonaceous chondrites. So far, the 13C- and D-enriched signature of water-extractable carboxylic acids has implied an interstellar contribution to their origin. However, it also has been proposed that monocarboxylic acids could be formed by aqueous reaction on the Meteorite Parent Body. In this study, we conducted hydrous pyrolysis of macromolecular organic matter purified from the Murchison Meteorite (CM2) to examine the generation of monocarboxylic acids with their stable carbon isotope measurement. During hydrous pyrolysis of macromolecular organic matter at 270-330 °C, monocarboxylic acids with carbon numbers ranging from 2 (C2) to 5 (C5) were detected, acetic acid (CH3COOH; C2) being the most abundant. The concentration of the generated acetic acid increased with increasing reaction temperature; up to 0.48 mmol acetic acid/g macromolecular organic matter at 330 °C. This result indicates that the Murchison macromolecule has a potential to generate at least ~0.4 mg acetic acid/g Meteorite, which is about four times higher than the amount of water-extractable acetic acid reported from Murchison. The carbon isotopic composition of acetic acid generated by hydrous pyrolysis of macromolecular organic matter is ~-27‰ (versus PDB), which is much more depleted in 13C than the water-extractable acetic acid reported from Murchison. Intramolecular carbon isotope distribution shows that methyl (CH3-)-C is more enriched in 13C relative to carboxyl (-COOH)-C, indicating a kinetic process for this formation. Although the experimental condition of this study (i.e., 270-330 °C for 72 h) may not simulate a reaction condition on Parent bodies of carbonaceous chondrite, it may be possible to generate monocarboxylic acids at lower temperatures for a longer period of time.
Christopher D. K. Herd - One of the best experts on this subject based on the ideXlab platform.
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unusual nonterrestrial l proteinogenic amino acid excesses in the tagish lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approximately 43-59%) of the alpha-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha hydrogen protein amino acid, was found to be nearly racemic (D much approximately L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and 1)- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of non terrestrial L-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
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Unusual Nonterrestrial L-proteinogenic Amino Acid excesses in the Tagish Lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large l-enantiomeric excesses (lee 43-59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another a-hydrogen protein amino acid, was found to be nearly racemic (d l) using both techniques. Carbon isotope measurements of d- and l-aspartic acid and d- and l-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the l-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial l-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large l-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of nonterrestrial l-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
Daniel P. Glavin - One of the best experts on this subject based on the ideXlab platform.
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unusual nonterrestrial l proteinogenic amino acid excesses in the tagish lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approximately 43-59%) of the alpha-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha hydrogen protein amino acid, was found to be nearly racemic (D much approximately L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and 1)- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of non terrestrial L-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
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Unusual Nonterrestrial L-proteinogenic Amino Acid excesses in the Tagish Lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large l-enantiomeric excesses (lee 43-59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another a-hydrogen protein amino acid, was found to be nearly racemic (d l) using both techniques. Carbon isotope measurements of d- and l-aspartic acid and d- and l-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the l-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial l-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large l-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of nonterrestrial l-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
Michael P. Callahan - One of the best experts on this subject based on the ideXlab platform.
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investigation of pyridine carboxylic acids in cm2 carbonaceous chondrites potential precursor molecules for ancient coenzymes
Geochimica et Cosmochimica Acta, 2014Co-Authors: Karen E Smith, Michael P. Callahan, Jason P. Dworkin, P A Gerakines, Christopher H HouseAbstract:The distribution and abundances of pyridine carboxylic acids (including nicotinic acid) in eight CM2 carbonaceous chondrites (ALH 85013, DOM 03183, DOM 08003, EET 96016, LAP 02333, LAP 02336, LEW 85311, and WIS 91600) were investigated by liquid chromatography coupled to UV detection and high resolution Orbitrap mass spectrometry. We find that pyridine monocarboxylic acids are prevalent in CM2-type chondrites and their abundance negatively correlates with the degree of pre-terrestrial aqueous alteration that the Meteorite Parent Body experienced. We also report the first detection of pyridine dicarboxylic acids in carbonaceous chondrites. Additionally, we carried out laboratory studies of proton-irradiated pyridine in carbon dioxide-rich ices (a 1:1 mixture) to serve as a model of the interstellar ice chemistry that may have led to the synthesis of pyridine carboxylic acids. Analysis of the irradiated ice residue shows that a comparable suite of pyridine mono- and dicarboxylic acids was produced, although aqueous alteration may still play a role in the synthesis (and ultimate yield) of these compounds in carbonaceous Meteorites. Nicotinic acid is a precursor to nicotinamide adenine dinucleotide, a likely ancient molecule used in cellular metabolism in all of life, and its common occurrence in CM2 chondrites may indicate that Meteorites may have been a source of molecules for the emergence of more complex coenzymes on the early Earth.
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unusual nonterrestrial l proteinogenic amino acid excesses in the tagish lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approximately 43-59%) of the alpha-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha hydrogen protein amino acid, was found to be nearly racemic (D much approximately L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and 1)- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of non terrestrial L-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
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Unusual Nonterrestrial L-proteinogenic Amino Acid excesses in the Tagish Lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large l-enantiomeric excesses (lee 43-59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another a-hydrogen protein amino acid, was found to be nearly racemic (d l) using both techniques. Carbon isotope measurements of d- and l-aspartic acid and d- and l-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the l-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial l-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large l-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of nonterrestrial l-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
Jason P. Dworkin - One of the best experts on this subject based on the ideXlab platform.
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investigation of pyridine carboxylic acids in cm2 carbonaceous chondrites potential precursor molecules for ancient coenzymes
Geochimica et Cosmochimica Acta, 2014Co-Authors: Karen E Smith, Michael P. Callahan, Jason P. Dworkin, P A Gerakines, Christopher H HouseAbstract:The distribution and abundances of pyridine carboxylic acids (including nicotinic acid) in eight CM2 carbonaceous chondrites (ALH 85013, DOM 03183, DOM 08003, EET 96016, LAP 02333, LAP 02336, LEW 85311, and WIS 91600) were investigated by liquid chromatography coupled to UV detection and high resolution Orbitrap mass spectrometry. We find that pyridine monocarboxylic acids are prevalent in CM2-type chondrites and their abundance negatively correlates with the degree of pre-terrestrial aqueous alteration that the Meteorite Parent Body experienced. We also report the first detection of pyridine dicarboxylic acids in carbonaceous chondrites. Additionally, we carried out laboratory studies of proton-irradiated pyridine in carbon dioxide-rich ices (a 1:1 mixture) to serve as a model of the interstellar ice chemistry that may have led to the synthesis of pyridine carboxylic acids. Analysis of the irradiated ice residue shows that a comparable suite of pyridine mono- and dicarboxylic acids was produced, although aqueous alteration may still play a role in the synthesis (and ultimate yield) of these compounds in carbonaceous Meteorites. Nicotinic acid is a precursor to nicotinamide adenine dinucleotide, a likely ancient molecule used in cellular metabolism in all of life, and its common occurrence in CM2 chondrites may indicate that Meteorites may have been a source of molecules for the emergence of more complex coenzymes on the early Earth.
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unusual nonterrestrial l proteinogenic amino acid excesses in the tagish lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approximately 43-59%) of the alpha-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha hydrogen protein amino acid, was found to be nearly racemic (D much approximately L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and 1)- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of non terrestrial L-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.
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Unusual Nonterrestrial L-proteinogenic Amino Acid excesses in the Tagish Lake Meteorite
Meteoritics & Planetary Science, 2012Co-Authors: Daniel P. Glavin, Jamie E. Elsila, Aaron S. Burton, Michael P. Callahan, Jason P. Dworkin, Robert W. Hilts, Christopher D. K. HerdAbstract:The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large l-enantiomeric excesses (lee 43-59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another a-hydrogen protein amino acid, was found to be nearly racemic (d l) using both techniques. Carbon isotope measurements of d- and l-aspartic acid and d- and l-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the Meteorite. Alternate explanations for the l-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial l-enantiomer excess during aqueous alteration on the Meteorite Parent Body could have led to the large l-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of nonterrestrial l-proteinogenic amino acid excesses in the Tagish Lake Meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.