Connecting molecular biomarkers, mineralogical composition, and microbial diversity from Mars analog lava tubes.

Autor: Palma V; HERCULES Laboratory, University of Évora, Évora, Portugal., González-Pimentel JL; HERCULES Laboratory, University of Évora, Évora, Portugal., Jimenez-Morillo NT; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., Sauro F; Department of Earth Sciences and Environmental Geology, University of Bologna, Italy., Gutiérrez-Patricio S; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., De la Rosa JM; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., Tomasi I; Geosciences Department, University of Padova, Padova, Italy., Massironi M; Geosciences Department, University of Padova, Padova, Italy., Onac BP; Karst Research Group, School of Geosciences, University of South Florida, Tampa, FL, USA; Emil G. Racoviță Institute, Babeș-Bolyai University, Cluj-Napoca, Romania., Tiago I; CFE-Center for Functional Ecology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal., González-Pérez JA; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., Laiz L; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., Caldeira AT; HERCULES Laboratory, University of Évora, Évora, Portugal., Cubero B; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain., Miller AZ; HERCULES Laboratory, University of Évora, Évora, Portugal; Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS-CSIC), Sevilla, Spain. Electronic address: anamiller@irnas.csic.es.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2024 Feb 25; Vol. 913, pp. 169583. Date of Electronic Publication: 2023 Dec 26.
DOI: 10.1016/j.scitotenv.2023.169583
Abstrakt: Lanzarote (Canary Islands, Spain) is one of the best terrestrial analogs to Martian volcanology. Particularly, Lanzarote lava tubes may offer access to recognizably preserved chemical and morphological biosignatures valuable for astrobiology. By combining microbiological, mineralogical, and organic geochemistry tools, an in-depth characterization of speleothems and associated microbial communities in lava tubes of Lanzarote is provided. The aim is to untangle the underlying factors influencing microbial colonization in Earth's subsurface to gain insight into the possibility of similar subsurface microbial habitats on Mars and to identify biosignatures preserved in lava tubes unequivocally. The microbial communities with relevant representativeness comprise chemoorganotrophic, halophiles, and/or halotolerant bacteria that have evolved as a result of the surrounding oceanic environmental conditions. Many of these bacteria have a fundamental role in reshaping cave deposits due to their carbonatogenic ability, leaving behind an organic record that can provide evidence of past or present life. Based on functional profiling, we infer that Crossiella is involved in fluorapatite precipitation via urea hydrolysis and propose its Ca-rich precipitates as compelling biosignatures valuable for astrobiology. In this sense, analytical pyrolysis, stable isotope analysis, and chemometrics were conducted to characterize the complex organic fraction preserved in the speleothems and find relationships among organic families, microbial taxa, and precipitated minerals. We relate organic compounds with subsurface microbial taxa, showing that organic families drive the microbiota of Lanzarote lava tubes. Our data indicate that bacterial communities are important contributors to biomarker records in volcanic-hosted speleothems. Within them, the lipid fraction primarily consists of low molecular weight n-alkanes, α-alkenes, and branched-alkenes, providing further evidence that microorganisms serve as the origin of organic matter in these formations. The ongoing research in Lanzarote's lava tubes will help develop protocols, routines, and predictive models that could provide guidance on choosing locations and methodologies for searching potential biosignatures on Mars.
Competing Interests: Declaration of competing interest The authors declare no competing financial interest or personal relationships that could have influenced the work reported in this paper.
(Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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