Examinando por Autor "Escudero, C."

Mostrando 1 - 4 de 4

Acceso Abierto
Biological production of H2, CH4 and CO2 in the deep subsurface of the Iberian Pyrite Belt
(Society for Applied Microbiology, 2021-05-10) Sanz, J. L.; Escudero, C.; Carrizo, D.; Amils, R.; Rodríguez Rivas, Noé; Agencia Estatal de Investigación (AEI); Sanz, J. L. [0000-0003-3226-3967]; Rodríguez, N. [0000-0003-4109-4851]; Escudero, C. [0000-0003-1240-4144]; Carrizo, D. [0000-0003-1568-4591]; Amils, R. [0000-0002-7560-1033]
Most of the terrestrial deep subsurfaces are oligotrophic environments in which some gases, mainly H2, CH4 and CO2, play an important role as energy and/or carbon sources. In this work, we assessed their biotic and abiotic origin in samples from subsurface hard-rock cores of the Iberian Pyrite Belt (IPB) at three different depths (414, 497 and 520 m). One set of samples was sterilized (abiotic control) and all samples were incubated under anaerobic conditions. Our results showed that H2, CH4 and CO2 remained low and constant in the sterilized controls while their levels were 4, 4.1 and 2.5 times higher respectively, in the unsterilized samples compared to the abiotic controls. The δ13CCH4-values measured in the samples (range −31.2 to −43.0 ‰) reveals carbon isotopic signatures that are within the range for biological methane production. Possible microorganisms responsible for the biotic production of the gases were assessed by CARD-FISH. The analysis of sequenced genomes of detected microorganisms within the subsurface of the IPB allowed to identify possible metabolic activities involved in H2 (Rhodoplanes, Shewanella and Desulfosporosinus), CH4 (Methanobacteriales) and CO2 production. The obtained results suggest that part of the H2, CH4 and CO2 detected in the deep subsurface has a biological origin.
Acceso Abierto
Methanogenesis at High Temperature, High Ionic Strength and Low pH in the Volcanic Area of Dallol, Ethiopia
(Multidisciplinary Digital Publishing Institute (MDPI), 2021-06-06) Sanz, J. L.; Escudero, C.; Carrizo, D.; Amils, R.; Gómez, F.; Rodríguez Rivas, Noé; Agencia Estatal de Investigación (AEI); Sanz, J. L. [0000-0003-3226-3967]; Escudero, C. [0000-0003-1240-4144]; Carrizo, D. [0000-0003-1568-4591]; Amils, R. [0000-0002-7560-1033]; Gómez, F. [0000-0001-9977-7060]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Dallol geothermal area originated as a result of seismic activity and the presence of a shallow underground volcano, both due to the divergence of two tectonic plates. In its ascent, hot water dissolves and drags away the subsurface salts. The temperature of the water that comes out of the chimneys is higher than 100 °C, with a pH close to zero and high mineral concentration. These factors make Dallol a polyextreme environment. So far, nanohaloarchaeas, present in the salts that form the walls of the chimneys, have been the only living beings reported in this extreme environment. Through the use of complementary techniques: culture in microcosms, methane stable isotope signature and hybridization with specific probes, the methanogenic activity in the Dallol area has been assessed. Methane production in microcosms, positive hybridization with the Methanosarcinales probe and the δ13CCH4-values measured, show the existence of extensive methanogenic activity in the hydrogeothermic Dallol system. A methylotrophic pathway, carried out by Methanohalobium and Methanosarcina-like genera, could be the dominant pathway for methane production in this environment.
Acceso Abierto
The Molecular Record of Metabolic Activity in the Subsurface of the Río Tinto Mars Analog
(Mary Ann Liebert Publishers, 2021-08-26) Fernández Remolar, D. C.; Gómez Ortiz, D.; Huang, T.; Anglés, A.; Shen, Y.; Hu, Q.; Amils, R.; Escudero, C.; Banerjee, N. R.; Rodríguez Rivas, Noé; Fundo para o Desenvolvimento das Ciências e da Tecnologia (FDCT); China National Space Administration (CNSA)
In the subsurface, the interplay between microbial communities and the surrounding mineral substrate, potentially used as an energy source, results in different mineralized structures. The molecular composition of such structures can record and preserve information about the metabolic pathways that have produced them. To characterize the molecular composition of the subsurface biosphere, we have analyzed some core samples by time-of-flight secondary ion mass spectrometry (ToF-SIMS) that were collected in the borehole BH8 during the operations of the Mars Analog and Technology Experiment (MARTE) project. The molecular analysis at a micron-scale mapped the occurrence of several inorganic complexes bearing PO3-, SOx(2 to 4)-, NOx(2,3)-, FeOx(1,2)-, SiO2-, and Cl-. Their distribution correlates with organic molecules that were tentatively assigned to saturated and monounsaturated fatty acids, polyunsaturated fatty acids, saccharides, phospholipids, sphingolipids, and potential peptide fragments. SOx- appear to be mineralizing some microstructures larger than 25 microns, which have branched morphologies, and that source SO3-bearing adducts. PO3-rich compounds occur in two different groups of microstructures which size, morphology, and composition are different. While a group of >40-micron sized circular micronodules lacks organic compounds, an ovoidal microstructure is associated with m/z of other lipids. The NO2-/NO3- and Cl- ions occur as small microstructure clusters (<20 microns), but their distribution is dissimilar to the mineralized microstructures bearing PO3-, and SO3-. However, they have a higher density in areas with more significant enrichment in iron oxides that are traced by different Fe-bearing anions like FeO2-. The distribution of the organic and inorganic negative ions, which we suggest, resulted from the preservation of at least three microbial consortia (PO4--, and NO2--/NO3--mineralizers PO4-lipid bearing microstructures), would have resulted from different metabolic and preservation pathways.
Acceso Abierto
Visualizing Microorganism-Mineral Interaction in the Iberian Pyrite Belt Subsurface: The Acidovorax Case
(Extreme Microbiology, 2020-11-26) Escudero, C.; Ares, J. R.; Martínez, J. M.; Gómez, F.; Amils, R.; Martínez del Campo, María; Lorente Sánchez, Cristina; Agencia Estatal de Investigación (AEI); Martínez, J. M. [0000-0003-3954-2985]; Escudero, C. [0000-0003-1240-4144]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Despite being considered an extreme environment, several studies have shown that life in the deep subsurface is abundant and diverse. Microorganisms inhabiting these systems live within the rock pores and, therefore, the geochemical and geohydrological characteristics of this matrix may influence the distribution of underground biodiversity. In this study, correlative fluorescence and Raman microscopy (Raman-FISH) was used to analyze the mineralogy associated with the presence of members of the genus Acidovorax, an iron oxidizing microorganisms, in native rock samples of the Iberian Pyrite Belt subsurface. Our results suggest a strong correlation between the presence of Acidovorax genus and pyrite, suggesting that the mineral might greatly influence its subsurface distribution.