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Biology subjects

Barberan, A.

Publications and source records attributed to Barberan, A..

4 recordsLinked to original sources

Soil viral response to drought disturbance and ecosystem recovery in an artificial rainforest

Anthropogenic climate change is driving increased temperature and altered precipitation patterns in tropical rainforests, yet the impact of severe drought on soil viral communities and their recovery capacity remains poorly understood. Soil viruses can exert strong controls on bacterial populations impacting microbially-mediated soil processes such as carbon cycling. At the same time, viruses are very sensitive to changes in the soil environment. We leverage meta-omics data from soils collected during a two-month drought and one-month recovery experiment carried in the Biosphere 2 Tropical Rainforest artificial biome. Our results indicate that soil viral community structure responds to small scale soil habitat heterogeneity more strongly than on overall changes in moisture. Additionally, the abundance of soil viruses was associated with a higher diversity of metabolites in the soil, suggesting viruses play a key role in soil biogeochemical processes. Altogether, our study suggests that soil viruses are an active part of tropical rainforest soil microbial communities and that is necessary to understand their response to drought.

microbiology↗

Differences in the genomic potential of soil bacterial and viral communities between urban greenspaces and natural arid soils

Urban green spaces provide essential ecosystem services are ever more important in arid cities. However, the design and management of these greenspaces often require physicochemical transformations whose effect in the balance of the arid urban ecosystems is normally not accounted for. In this project, we leverage metagenomic data from soil microbial communities of urban greenspaces and neighboring natural areas in a city from the arid Southwestern USA (Tucson, Arizona) to understand the differences in microbial (bacterial and viral) community structure and function in urban greenspaces compared to natural arid soils. We found bacterial and viral communities to be distinct between urban greenspace and natural arid soils, viral communities showing a starker differentiation. Urban greenspace bacteria were less versatile and showed higher genetic potential for the simple carbohydrate consumption and nitrogen reduction. Moreover, bacteria in urban greenspaces exhibit higher genetic potential for resistance to heavy metals, and certain clinical antibiotics. Our results suggest that the conversion of arid natural land to urban greenspaces determines the soil microbiome structure and functioning, and potentially its ability to adapt to the changing environment. IMPORTANCEUrban green spaces are critical for the sustainability of arid cities. Nevertheless, they require deep soil physicochemical transformations. Soil bacterial and viral communities are responsible for soil functioning and provision of some ecosystem services, but they are also highly influenced by changes in the soil environment. The significance of our research is in illustrating the structural and functional changes that microbial and viral communities undergo in urban soils of arid cities, and their potential impacts on urban greenspace soil processes.

ecology↗

Seasonal niche differentiation between evolutionary closely related marine bacteria

Bacteria are highly dynamic in marine environments, where they play key biogeochemical roles. Here, we tested how similar the niche of closely related marine bacteria is and what are the environmental parameters modulating their ecological responses in a coastal oligotrophic time series. We further explored how conserved the niche is at broader taxonomic levels. We found that, for certain genera, niche similarity decreases as nucleotide divergence increases between closely related amplicon sequence variants, a pattern compatible with selection of similar taxa through habitat filtering. Additionally, we observed evidence of niche partitioning within various genera shown by the distinct seasonal patterns of closely related taxa. At broader levels, we did not observe coherent seasonal trends at the class level, with the order and family ranks conditioned to the patterns that exist at the genus level. This study explores the coexistence of niche overlap and niche partitioning in a coastal marine environment.

microbiology↗

Light into the darkness: Unifying the known and unknown coding sequence space in microbiome analyses

Genes of unknown function are among the biggest challenges in molecular biology, especially in microbial systems, where 40%-60% of the predicted genes are unknown. Despite previous attempts, systematic approaches to include the unknown fraction into analytical workflows are still lacking. Here, we propose a conceptual framework and a computational workflow that bridge the known-unknown gap in genomes and metagenomes. We showcase our approach by exploring 415,971,742 genes predicted from 1,749 metagenomes and 28,941 bacterial and archaeal genomes. We quantify the extent of the unknown fraction, its diversity, and its relevance across multiple biomes. Furthermore, we provide a collection of 283,874 lineage-specific genes of unknown function for Cand. Patescibacteria, being a significant resource to expand our understanding of their unusual biology. Finally, by identifying a target gene of unknown function for antibiotic resistance, we demonstrate how we can enable the generation of hypotheses that can be used to augment experimental data.

microbiology↗