Structure and isotopic ratios of aliphatic side chains in the insoluble organic matter of the Murchison carbonaceous chondrite

Dust grains of organic matter were the main reservoir of C and N in the forming Solar System and are thus considered to be an essential ingredient for the emergence of life. However, the physical environment and the chemical mechanisms at the origin of these organic grains are still highly debated. In this study, we report high-precision triple oxygen isotope composition for insoluble organic matter isolated from three emblematic carbonaceous chondrites, Orgueil, Murchison, and Cold Bokkeveld. These results suggest that the O isotope composition of carbonaceous chondrite insoluble organic matter falls on a slope 1 correlation line in the triple oxygen isotope diagram. The lack of detectable mass-dependent O isotopic fractionation, indicated by the slope 1 line, suggests that the bulk of carbonaceous chondrite organics did not form on asteroidal parent bodies during low-temperature hydrothermal events. On the other hand, these O isotope data, together with the H and N isotope characteristics of insoluble organic matter, may indicate that parent bodies of different carbonaceous chondrite types largely accreted organics formed locally in the protosolar nebula, possibly by photochemical dissociation of C-rich precursors.

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Molecular study of insoluble organic matter in Kainsaz CO3 carbonaceous chondrite: Comparison with CI and CM IOM

Meteoritics and Planetary Science ◽

10.1111/j.1945-5100.2008.tb01115.x ◽

2008 ◽

Vol 43 (7) ◽

pp. 1099-1111 ◽

Cited By ~ 17

Author(s):

Laurent REMUSAT ◽

Corentin GUILLOU ◽

Jean-Noël ROUZAUD ◽

Laurent BINET ◽

Sylvie DERENNE ◽

...

Keyword(s):

Organic Matter ◽

Carbonaceous Chondrite ◽

Molecular Study ◽

Insoluble Organic Matter

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Organic matter in carbonaceous chondrite lithologies of Almahata Sitta: Incorporation of previously unsampled carbonaceous chondrite lithologies into ureilitic regolith

Meteoritics and Planetary Science ◽

10.1111/maps.13713 ◽

2021 ◽

Author(s):

Yoko Kebukawa ◽

Michael. E. Zolensky ◽

Cyrena A. Goodrich ◽

Motoo Ito ◽

Nanako O. Ogawa ◽

...

Keyword(s):

Organic Matter ◽

Carbonaceous Chondrite

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Speciation of organosulfur compounds in carbonaceous chondrites

Scientific Reports ◽

10.1038/s41598-021-86576-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Alexander Zherebker ◽

Yury Kostyukevich ◽

Dmitry S. Volkov ◽

Ratibor G. Chumakov ◽

Lukas Friederici ◽

...

Keyword(s):

Organic Matter ◽

Analytical Techniques ◽

Ion Cyclotron Resonance ◽

Organosulfur Compounds ◽

Low Oxygen ◽

Fticr Ms ◽

Insoluble Organic Matter ◽

Composition And Structure ◽

Extractable Fraction ◽

The Individual

AbstractDespite broad application of different analytical techniques for studies on organic matter of chondrite meteorites, information about composition and structure of individual compounds is still very limited due to extreme molecular diversity of extraterrestrial organic matter. Here we present the first application of isotopic exchange assisted Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) for analysis of alkali extractable fraction of insoluble organic matter (IOM) of the Murchison and Allende meteorites. This allowed us to determine the individual S-containing ions with different types of sulfur atoms in IOM. Thiols, thiophenes, sulfoxides, sulfonyls and sulfonates were identified in both samples but with different proportions, which contribution corroborated with the hydrothermal and thermal history of the meteorites. The results were supported by XPS and thermogravimetric analysis coupled to FTICR MS. The latter was applied for the first time for analysis of chondritic IOM. To emphasize the peculiar extraterrestrial origin of IOM we have compared it with coal kerogen, which is characterized by the comparable complexity of molecular composition but its aromatic nature and low oxygen content can be ascribed almost exclusively to degradation of biomacromolecules.

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Synthesis of 13C-enriched amino acids with 13C-depleted insoluble organic matter in a formose-type reaction in the early solar system

Science Advances ◽

10.1126/sciadv.abd3575 ◽

2021 ◽

Vol 7 (18) ◽

pp. eabd3575

Author(s):

Yoshihiro Furukawa ◽

Yoshinari Iwasa ◽

Yoshito Chikaraishi

Keyword(s):

Aqueous Solution ◽

Organic Matter ◽

Solar System ◽

Acid Synthesis ◽

Soluble Organic Matter ◽

Early Solar System ◽

Cold Region ◽

Amino Acid Synthesis ◽

Type Reaction ◽

Insoluble Organic Matter

Solvent-soluble organic matter (SOM) in meteorites, which includes life’s building molecules, is suspected to originate from the cold region of the early solar system, on the basis of 13C enrichment in the molecules. Here, we demonstrate that the isotopic characteristics are reproducible in amino acid synthesis associated with a formose-type reaction in a heated aqueous solution. Both thermochemically driven formose-type reaction and photochemically driven formose-type reaction likely occurred in asteroids and ice-dust grains in the early solar system. Thus, the present results suggest that the formation of 13C-enriched SOM was not specific to the cold outer protosolar disk or the molecular cloud but occurred more widely in the early solar system.

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