Southwest Spain's Río Tinto is a stressful acidic microbial habitat with a noticeably high concentration of toxic heavy metals. Nevertheless, it has an unexpected degree of eukaryotic diversity in its basin, with a high diversity of fungal saprotrophs. Although some studies on the eukaryotic diversity in Rio Tinto have been published, none of them used molecular methodologies to describe the fungal diversity and taxonomic affiliations that emerge along the river in different seasons.
View Article and Find Full Text PDFThe mangrove ecosystems of the Department of Atlántico (Colombian Caribbean) are seriously threatened by problems of hypersalinization and contamination, especially by heavy metals from the Magdalena River. The mangrove plants have developed various mechanisms to adapt to these stressful conditions, as well as the associated microbial populations that favor their growth. In the present work, the tolerance and detoxification capacity to heavy metals, especially to mercury, of a halotolerant endophytic bacterium isolated from the species located in the Balboa Swamp in the Department of Atlántico was characterized.
View Article and Find Full Text PDFExecutive Summary: Microbes are all pervasive in their distribution and influence on the functioning and well-being of humans, life in general and the planet. Microbially-based technologies contribute hugely to the supply of important goods and services we depend upon, such as the provision of food, medicines and clean water. They also offer mechanisms and strategies to mitigate and solve a wide range of problems and crises facing humanity at all levels, including those encapsulated in the sustainable development goals (SDGs) formulated by the United Nations.
View Article and Find Full Text PDFThis report describes acidic microbial mats containing cyanobacteria that are strongly associated to precipitated minerals in the source area of Río Tinto. Río Tinto (Huelva, Southwestern Spain) is an extreme acidic environment where iron and sulfur cycles play a fundamental role in sustaining the extremely low pH and the high concentration of heavy metals, while maintaining a high level of microbial diversity. These multi-layered mineral deposits are stable all year round and are characterized by a succession of thick greenish-blue and brownish layers mainly composed of natrojarosite.
View Article and Find Full Text PDFT2.26MG-112.2 is a strain that has been isolated from the deep subsurface of the Iberian Pyrite Belt.
View Article and Find Full Text PDFVitamin B is an enzymatic cofactor that is essential for both eukaryotes and prokaryotes. The development of life in extreme environments depends on cofactors such as vitamin B as well. The genomes of twelve microorganisms isolated from the deep subsurface of the Iberian Pyrite Belt have been analyzed in search of enzymatic activities that require vitamin B or are involved in its synthesis and import.
View Article and Find Full Text PDFThe RT7 strain was isolated from an extreme acidic environment and identified. The biodegradation capabilities of the strain using different carbon sources (glucose, oleic acid, Tween 80, PEG 200, and the combination of glucose-Tween 80) were evaluated via an indirect impedance technique. The glucose-Tween 80 combination was further studied using nuclear magnetic resonance (NMR).
View Article and Find Full Text PDFPractical experiments drive important scientific discoveries in biology, but theory-based research studies also contribute novel-sometimes paradigm-changing-findings. Here, we appraise the roles of theory-based approaches focusing on the experiment-dominated wet-biology research areas of microbial growth and survival, cell physiology, host-pathogen interactions, and competitive or symbiotic interactions. Additional examples relate to analyses of genome-sequence data, climate change and planetary health, habitability, and astrobiology.
View Article and Find Full Text PDFTirez was a small and seasonal endorheic athalassohaline lagoon that was located in central Spain. In recent years, the lagoon has totally dried out, offering for the first time the opportunity to analyze its desiccation process as a "time-analog" to similar events occurred in paleolakes with varying salinity during the wet-to-dry transition on early Mars. On the martian cratered highlands, an early period of water ponding within enclosed basins evolved to a complete desiccation of the lakes, leading to deposition of evaporitic sequences during the Noachian and into the Late Hesperian.
View Article and Find Full Text PDFLignocellulosic residues are amongst the most abundant waste products on Earth. Therefore, there is an increasing interest in the utilization of these residues for bioethanol production and for biorefineries to produce compounds of industrial interest. Enzymes that breakdown cellulose and hemicellulose into oligomers and monosaccharides are required in these processes and cellulolytic enzymes with optimum activity at a low pH area are desirable for industrial processes.
View Article and Find Full Text PDFMicrobial activity is a major contributor to the biogeochemical cycles that make up the life support system of planet Earth. A 613 m deep geomicrobiological perforation and a systematic multi-analytical characterization revealed an unexpected diversity associated with the rock matrix microbiome that operates in the subsurface of the Iberian Pyrite Belt (IPB). Members of 1 class and 16 genera were deemed the most representative microorganisms of the IPB deep subsurface and selected for a deeper analysis.
View Article and Find Full Text PDFThe RT6 strain was isolated and identified by morphological, biochemical and molecular tests from an extreme acidic environment, Rio Tinto (Huelva). Optimisation tests for exopolysaccharide (EPS) production in different culture media determined that the best medium was a minimal medium with glucose as the only carbon source. The exopolymer (EPS) produced by the strain was isolated and characterised using different techniques (GC-MS, HPLC/MSMS, ATR-FTIR, TGA, DSC).
View Article and Find Full Text PDFThe Iberian Pyrite Belt (IPB) is one of the largest deposits of sulphidic minerals on Earth. Río Tinto raises from its core, presenting low a pH and high metal concentration. Several drilling cores were extracted from the IPB's subsurface, and strain T2.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
August 2022
A Gram-stain-positive, moderately halophilic, aerobic, endospore-forming, rod-shaped bacterium, designated strain DP4-553-S, was isolated from hypersaline sediment collected from the Dalangtan Playa in the Qaidam Basin, Northwest PR China. Growth occurred within 0-21.6% (w/v) NaCl (optimum 7.
View Article and Find Full Text PDFThe Chiquini and Galaxias caves contain speleothems that are templated by long fungal structures. They have been associated with the carbonate lacustrine deposits in the margins of the Coipasa and Uyuni Salar basins. During a wetter episode, such carbonates formed at the end of the last glaciation raising the lake level to more than 100 m in the Tauca events (15-12 ky).
View Article and Find Full Text PDFIn the mining-impacted Rio Tinto, Spain, Fe-cycling microorganisms influence the transport of heavy metals (HMs) into the Atlantic Ocean. However, it remains largely unknown how spatial and temporal hydrogeochemical gradients along the Rio Tinto shape the composition of Fe-cycling microbial communities and how this in turn affects HM mobility. Using a combination of DNA- and RNA-based 16S rRNA (gene) amplicon sequencing and hydrogeochemical analyses, we explored the impact of pH, Fe(III), Fe(II), and Cl on Fe-cycling microorganisms.
View Article and Find Full Text PDFThe preservation of biosignatures on Mars is largely associated with extensive deposits of clays formed under mild early Noachian conditions (> 3.9 Ga). They were followed by widespread precipitation of acidic sulfates considered adverse for biomolecule preservation.
View Article and Find Full Text PDFIn 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.
View Article and Find Full Text PDFThe drilling of the Rio Tinto basement has provided evidence of an underground microbial community primarily sustained by the Fe and S metabolism through the biooxidation of pyrite orebodies. Although the gossan is the microbial activity product, which dates back to the Oligocene (25 Ma), no molecular evidence of such activity in the past has been reported yet. A Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) molecular analysis of a subsurface sample in the Peña de Hierro basement has provided novel data of the ancient underground microbial community.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFNGS long-reads sequencing technologies (or third generation) such as Pacific BioSciences (PacBio) have revolutionized the sequencing field over the last decade improving multiple genomic applications like de novo genome assemblies. However, their error rate, mostly involving insertions and deletions (indels), is currently an important concern that requires special attention to be solved. Multiple algorithms are available to fix these sequencing errors using short reads (such as Illumina), although they require long processing times and some errors may persist.
View Article and Find Full Text PDFMost of the terrestrial deep subsurfaces are oligotrophic environments in which some gases, mainly H , CH and CO , 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.
View Article and Find Full Text PDFThe exploration of extreme environments has led to the discovery of numerous environments that were, until recently, considered uninhabitable [...
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