Biology subjects

DELGADO BAQUERIZO, M.

Publications and source records attributed to DELGADO BAQUERIZO, M..

3 recordsLinked to original sources

bioRxiv2023

Metagenomics untangles metabolic adaptations of Antarctic endolithic 1 bacteria at the fringe of habitability

BackgroundEndolithic niches offer an ultimate refuge, supplying buffered conditions for microorganisms that dwell inside rock airspaces. Yet, survival and growth strategies of Antarctic endolithic microbes residing in Earths driest and coldest desert remains virtually unknown. ResultsFrom 109 endolithic microbiomes, 4,539 metagenome-assembled genomes were generated, 49.3% of which were novel candidate bacterial species. We present evidence that trace gas oxidation and atmospheric chemosynthesis may be the prevalent strategies supporting metabolic activity and persistence of these ecosystems at the fringe of life and the limits of habitability. ConclusionsThese results represent the foundation to untangle adaptability at the edge of sustainability on Earth and on other dry Earth-like planetary bodies such as Mars.

microbiology↗

bioRxiv2023

Geography and environmental pressure are predictive of class-specific 1 radioresistance in black fungi

Black fungi are among the most resistant organisms to ionizing radiation on Earth. However, our current knowledge is based on studies on a few isolates, while the overall radioresistance limits across this microbial group and the relationship with local environmental conditions remains largely undetermined. To address this knowledge gap, we assessed the survival of 101 strains of black fungi isolated across a worldwide spatial distribution to gamma radiation doses up to 100 kGy. We found that intra and inter-specific taxonomy, UV radiation and precipitation levels primarily influence the radioresistance in black fungi. Altogether, this study provides insights into the adaptive mechanisms of black fungi to extreme environments and highlights the role of local adaptation in shaping the survival capabilities of these extreme-tolerant organisms. Originality statementAlthough previous studies showed the extraordinary ability of a few strains of black fungi to survive ionizing radiation, the overall radioresistance of this group of organisms has not been defined yet. Moreover, how and why radioresistance shifts across environmental gradients remain virtually unknown. Here, we collected black fungi from locations across the globe and found that biogeography shapes the responses of black fungi to environmental stress with UV light being significantly correlated with radiotolerance. Our study provides a clear picture of the boundaries of life for black fungi under ionizing radiation; further, we demonstrate, for the first time, that this ability in such microorganisms, not only is related to taxonomy, but also may be a consequence of their adaptation to various factors encountered in the environment where they live.

microbiology↗

bioRxiv2021

Rock traits drive complex microbial communities at the edge of life

Antarctic deserts are among the driest and coldest ecosystems of the planet; there, some microbes hang on to life under these extreme conditions inside porous rocks, forming the so-called endolithic communities. Yet, the contribution of distinct rock traits to support complex microbial assemblies remains poorly determined. Here, we combined an extensive Antarctic rock survey with rock microbiome sequencing and ecological networks, and found that contrasting combinations of microclimatic and rock traits such as thermal inertia, porosity, iron concentration and quartz cement can help explain the multiple complex and independent microbial assemblies found in Antarctic rocks. Our work highlights the pivotal role of rocky substrate heterogeneity in sustaining contrasting groups of microorganisms, which is essential to understand life at the edge on Earth, and for searching life on other rocky planets such as Mars.

microbiology↗