Academic Journal
Selective chemical degradation of silica sinters of the Taupo Volcanic Zone (New Zealand). Implications for early Earth and Astrobiology.
| Τίτλος: | Selective chemical degradation of silica sinters of the Taupo Volcanic Zone (New Zealand). Implications for early Earth and Astrobiology. |
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| Συγγραφείς: | Chaves Torres L; Organic Geochemistry Unit, School of Chemistry, University of Bristol, Bristol, UK.; Cabot Institute, University of Bristol, Bristol, UK., Kaur G; Organic Geochemistry Unit, School of Chemistry, University of Bristol, Bristol, UK.; Cabot Institute, University of Bristol, Bristol, UK., Melbourne LA; Organic Geochemistry Unit, School of Chemistry, University of Bristol, Bristol, UK.; Cabot Institute, University of Bristol, Bristol, UK., Pancost RD; Organic Geochemistry Unit, School of Chemistry, University of Bristol, Bristol, UK.; Cabot Institute, University of Bristol, Bristol, UK.; School of Earth Sciences, University of Bristol, Bristol, UK. |
| Πηγή: | Geobiology [Geobiology] 2019 Jul; Vol. 17 (4), pp. 449-464. Date of Electronic Publication: 2019 Apr 24. |
| Τύπος έκδοσης: | Journal Article; Research Support, Non-U.S. Gov't |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: Wiley Country of Publication: England NLM ID: 101185472 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1472-4669 (Electronic) Linking ISSN: 14724669 NLM ISO Abbreviation: Geobiology Subsets: MEDLINE |
| Imprint Name(s): | Original Publication: Oxford, UK : Wiley, 2003- |
| Ιατρικοί όροι (MeSH): | Evolution, Planetary* , Exobiology*, Geologic Sediments/*chemistry , Lipids/*analysis , Silicon Dioxide/*chemistry, Archaea/metabolism ; Bacteria/metabolism ; Earth, Planet ; New Zealand |
| Περίληψη: | Most organic matter (OM) on Earth occurs as kerogen-like materials, that is naturally formed macromolecules insoluble with standard organic solvents. The formation of this insoluble organic matter (IOM) is a topic of much interest, especially when it limits the detection of compounds of geomicrobiological interest. For example, studies that search for biomarker evidence of life on early Earth or other planets usually use solvent-based extractions. This leaves behind a pool of OM as unexplored post-extraction residues, potentially containing diagnostic biomarkers. Since the IOM has an enhanced potential for preservation compared to soluble OM, analysing IOM-released biomarkers can also provide even deeper insights into the ecology of ancient settings, with implications for early Earth and Astrobiology investigations. Here, we analyse the prokaryotic lipid biosignature within soluble and IOM of the Taupo Volcanic Zone (TVZ) silica sinters, which are key analogues in the search for life. We apply sequential solvent extractions and a selective chemical degradation upon the post-solvent extraction residue. Moreover, we compare the IOM from TVZ sinters to analogous studies on peat and marine sediments to assess patterns in OM insolubilisation across the geosphere. Consistent with previous work, we find significant but variable proportions-1%-45% of the total prokaryotic lipids recovered-associated with IOM fractions. This occurs even in recently formed silica sinters, likely indicating inherent cell insolubility. Moreover, archaeal lipids seem more prone to insolubilisation as compared to the bacterial analogues, which might enhance their preservation and also bias overall biomarkers interpretation. These observations are similar to those observed in other settings, confirming that even in a setting where the OM derives predominantly from prokaryotic sources, patterns of IOM formation/occurrence are conserved. Differences with other settings, however, such as the occurrence of archaeol in IOM fractions, could be indicative of different mechanisms for IOM formation that merit further exploration. (© 2019 John Wiley & Sons Ltd.) |
| Contributed Indexing: | Keywords: Astrobiology; Taupo Volcanic Zone; early Earth; prokaryotic membrane lipids; selective chemical degradation; silica sinters |
| Substance Nomenclature: | 0 (Lipids) 7631-86-9 (Silicon Dioxide) |
| Entry Date(s): | Date Created: 20190426 Date Completed: 20191029 Latest Revision: 20191210 |
| Update Code: | 20260130 |
| DOI: | 10.1111/gbi.12340 |
| PMID: | 31020785 |
| Βάση Δεδομένων: | MEDLINE |
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