Biology subjects

Rodriguez-Valera, F.

Publications and source records attributed to Rodriguez-Valera, F..

21 records · Page 2Linked to original sources

bioRxiv2018

Charting the diversity of Uncultured Viruses of Archaea and Bacteria

Viruses of Archaea and Bacteria are among the most abundant and diverse biological entities on Earth. Unraveling their biodiversity has been challenging due to methodological limitations. Recent advances in culture-independent techniques, such as metagenomics, shed light on viral dark matter, revealing thousands of new viral genomes at an unprecedented scale. However, these novel genomes have not been properly classified and the evolutionary associations between them were not resolved. Here, we performed phylogenomic analysis of nearly 200,000 viral genomic sequences to establish GL-UVAB: Genomic Lineages of Uncultured Viruses of Archaea and Bacteria. GL-UVAB yielded a 44-fold increase in the amount of classified genomes. The pan-genome content of the identified lineages revealed their infection strategies, potential to modulate host physiology and mechanisms to escape resistance systems. Furthermore, using GL-UVAB for annotating metagenomes from multiple ecosystems revealed elusive habitat distribution patterns of viral communities. These findings expand the understanding of the diversity, evolution and ecology of viruses of prokaryotes.

microbiology↗

bioRxiv2017

Numerous cultivated and uncultivated viruses encode ribosomal proteins

Text Text METHODS References Viruses modulate ecosystems by directly altering host metabolisms through auxiliary metabolic genes, which are obtained through random sampling of the host genome and rise to fixation, presumably through improved viral fitness by alleviating key metabolic bottlenecks during infection. Conspicuously, however, viral genomes are not known to encode the core components of translation machinery, such as ribosomal proteins (RPs), though genes for RPs S1 and S21 have been detected in viral metagenomes1,2. Here we augment this little-noticed observation using available reference genomes, global-scale viral metagenomic datasets, and functional assays for select proteins. We identify 15 different RPs across diverse viral genomes arising from cultivated viral isolates (5 RPs in 16 genomes) and metag ...

microbiology↗

bioRxiv2017

Fine Stratification Of Microbial Communities Through A Metagenomic Profile Of The Photic Zone

Most marine metagenomic studies of the marine photic zone analyze only samples taken at one or two depths. However, when the water column is stratified, physicochemical parameters change dramatically over relatively short depth intervals. We sampled the photic water column every 15m depth at a single point of an off-shore Mediterranean site during a period of strong stratification (early autumn) to evaluate the effects of small depth increases on the microbiome. Using genomic assembly and metagenomic read recruitment, we found major shifts in the community structure over small variations of depth, with most microbes showing a distribution limited to layers approximately 30 meters thick (stenobathic). Only some representatives of the SAR11 clade and the Sphingomonadaceae appeared to be eurybathic, spanning a greater range of depths. These results were confirmed by studying a single gene (rhodopsin) for which we also found narrow depth distributions. Our results highlight the importance of considering vertical distribution as a major element when analyzing the presence of marine clades and species or comparing the microbiome present at different locations.

microbiology↗