Biology subjects

Vinuesa, P.

Publications and source records attributed to Vinuesa, P..

5 recordsLinked to original sources

bioRxiv2025

The Stenotrophomonas maltophilia MntR miniregulon includes novel extracytoplasmic components and affects replication in Acanthamoeba castellanii phagosomes

Manganese homeostasis is essential for the environmental adaptability and pathogenic potential of Stenotrophomonas maltophilia, a bacterium that thrives across diverse and fluctuating niches. Here, we characterize the manganese homeostasis network of S. maltophilia strain Sm18, revealing a coordinated system that integrates conserved transporters with previously unrecognized components. Central to this system is an MntR-controlled miniregulon that includes the canonical Mn{superscript 2} importer MntH and exporter MntP, together with a TonB-dependent receptor (TBDR) and a periplasmic thioredoxin-fold protein (pTFP), both defining novel protein families with restricted phylogenetic distribution. Transcriptomic analyses under varying Mn{superscript 2} and Fe{superscript 2} conditions uncovered a tight interplay between these metals, highlighting the ferrophilic nature of S. maltophilia and the differential regulation of miniregulon components. Notably, the TBDR-pTFP module is strongly induced under combined Mn2+ and Fe2+ limitation, suggesting a specialized role in metal acquisition under nutrient-restricted conditions. Functional analyses demonstrated that MntP is required to prevent Mn toxicity even at sub-inhibitory concentrations, whereas MntH supports growth under oxidative stress and promotes intracellular replication within Acanthamoeba castellanii phagosomes. Together, these findings define a previously unrecognized Mn-responsive module that expands the MntR regulatory network and provides new insight into the mechanisms that enable S. maltophilia to adapt to metal-limited and host-associated environments.

microbiology↗

bioRxiv2020

Dynamics of infection in a novel group of promiscuous phages and hosts of multiple bacterial genera retrieved from river communities

Phages are generally described as species- or even strain-specific viruses, implying an inherent limitation for some to be maintained and spread in diverse bacterial communities. Moreover, phage isolation and host range determination rarely consider the phage ecological context, likely biasing our notion on phage specificity. Here we identified and characterized a novel group of promiscuous phages existing in rivers by using diverse bacteria isolated from the same samples, and then used this biological system to investigate infection dynamics in distantly related hosts. We assembled a diverse collection of over 600 native bacterial strains and used them to isolate six podophages, named Atoyac, from different geographic origin and capable of infecting six genera in the Gammaproteobacteria. Atoyac phage genomes are highly similar to each other but not to those currently available in the genome and metagenome public databases. Detailed comparison of the phages infectivity in diverse hosts and trough hundreds of interactions revealed variation in plating efficiency amongst bacterial genera, implying a cost associated with infection of distant hosts, and between phages, despite their sequence similarity. We show, through experimental evolution in single or alternate hosts of different genera, that plaque production efficiency is highly dynamic and tends towards optimization in hosts rendering low plaque formation. Complex adaptation outcomes observed in the evolution experiments differed between highly similar phages and suggest that propagation in multiple hosts may be key to maintain promiscuity in some viruses. Our study expands our knowledge of the virosphere and uncovers bacteria-phage interactions overlooked in natural systems. ImportanceIn natural environments, phages co-exist and interact with a broad variety of bacteria, posing a conundrum for narrow-host-range phages maintenance in diverse communities. This context is rarely considered in the study of host-phage interactions, typically focused on narrow-host-range viruses and their infectivity in target bacteria isolated from sources distinct to where the phages were retrieved from. By studying phage-host interactions in bacteria and viruses isolated from river microbial communities, we show that novel phages with promiscuous host range encompassing multiple bacterial genera can be found in the environment. Assessment of hundreds of interactions in diverse hosts revealed that similar phages exhibit different infection efficiency and adaptation patterns. Understanding host range is fundamental in our knowledge of bacteria-phage interactions and their impact in microbial communities. The dynamic nature of phage promiscuity revealed in our study has implications in different aspects of phage research such as horizontal gene transfer or phage therapy.

microbiology↗

bioRxiv2019

Global phylogeography and ancient evolution of the widespread human gut virus crAssphage

Microbiomes are vast communities of microbes and viruses that populate all natural ecosystems. Viruses have been considered the most variable component of microbiomes, as supported by virome surveys and examples of high genomic mosaicism. However, recent evidence suggests that the human gut virome is remarkably stable compared to other environments. Here we investigate the origin, evolution, and epidemiology of crAssphage, a widespread human gut virus. Through a global collaboratory, we obtained DNA sequences of crAssphage from over one-third of the worlds countries, and showed that its phylogeography is locally clustered within countries, cities, and individuals. We also found colinear crAssphage-like genomes in both Old-World and New-World primates, challenging genomic mosaicism and suggesting that the association of crAssphage with primates may be millions of years old. We conclude that crAssphage is a benign globetrotter virus that may have co-evolved with the human lineage and an integral part of the normal human gut virome.

microbiology↗

bioRxiv2018

GET_PHYLOMARKERS, a software package to select optimal orthologous clusters for phylogenomics and inferring pan-genome phylogenies, used for a critical geno-taxonomic revision of the genus Stenotrophomonas

The massive accumulation of genome-sequences in public databases promoted the proliferation of genome-level phylogenetic analyses in many areas of biological research. However, due to diverse evolutionary and genetic processes, many loci have undesirable properties for phylogenetic reconstruction. These, if undetected, can result in erroneous or biased estimates, particularly when estimating species trees from concatenated datasets. To deal with these problems, we developed GET_PHYLOMARKERS, a pipeline designed to identify high-quality markers to estimate robust genome phylogenies from the orthologous clusters, or the pan-genome matrix (PGM), computed by GET_HOMOLOGUES. In the first context, a set of sequential filters are applied to exclude recombinant alignments and those producing anomalous or poorly resolved trees. Multiple sequence alignments and maximum likelihood (ML) phylogenies are computed in parallel on multi-core computers. A ML species tree is estimated from the concatenated set of top-ranking alignments at the DNA or protein levels, using either FastTree or IQ-TREE (IQT). The latter is used by default due to its superior performance revealed in an extensive benchmark analysis. In addition, parsimony and ML phylogenies can be estimated from the PGM.\n\nWe demonstrate the practical utility of the software by analyzing 170 Stenotrophomonas genome sequences available in RefSeq and 10 new complete genomes of environmental S. maltophilia complex (Smc) isolates reported herein. A combination of core-genome and PGM analyses was used to revise the molecular systematics of the genus. An unsupervised learning approach that uses a goodness of clustering statistic identified 20 groups within the Smc at a core-genome average nucleotide identity of 95.9% that are perfectly consistent with strongly supported clades on the core- and pan-genome trees. In addition, we identified 14 misclassified RefSeq genome sequences, 12 of them labeled as S. maltophilia, demonstrating the broad utility of the software for phylogenomics and geno-taxonomic studies. The code, a detailed manual and tutorials are freely available for Linux/UNIX servers under the GNU GPLv3 license at https://github.com/vinuesa/get_phylomarkers. A docker image bundling GET_PHYLOMARKERS with GET_HOMOLOGUES is available at https://hub.docker.com/r/csicunam/get_homologues/, which can be easily run on any platform.

genomics↗

bioRxiv2017

Niche Partitioning In Sympatric Populations Of Aquatic Stenotrophomonas Uncovered By Evolutionary Species Delimitation

The genus Stenotrophomonas (Gammaproteobacteria) has a broad environmental distribution. S. maltophilia is its best known species because it is a globally emerging, multidrug-resistant (MDR), opportunistic pathogen. Members of this species are known to display high genetic, ecological and phenotypic diversity, forming the so-called S. maltophilia complex (Smc). Heterogeneous resistance and virulence phenotypes have been reported for environmental Smc isolates of diverse ecological origin. We hypothesized that this heterogeneity could be in part due to the potential lumping of several cryptic species in the Smc. Here we used state-of-the-art phylogenetic and population genetics methods to test this hypothesis based on the multilocus dataset available for the genus at pubmlst.org. It was extended with sequences from complete and draft genome sequences to assemble a comprehensive set of reference sequences. This framework was used to analyze 108 environmental isolates obtained in this study from the sediment and water column of four rivers and streams in Central Mexico, affected by contrasting levels of anthropogenic pollution. The aim of the study was to identify species in this collection, defined as genetically cohesive sequence clusters, and to determine the extent of their genetic, ecological and phenotypic differentiation. The multispecies coalescent, coupled with Bayes factor analysis was used to delimit species borders, together with population genetic structure analyses, recombination and gene flow estimates between sequence clusters.\n\nThese analyses consistently revealed that the Smc contains at least 5 significantly differentiated lineages: S. maltophilia and Smc1 to Smc4. Only S. maltophilia was found to be intrinsically MDR, all its members expressing metallo-{beta}-lactamases (MBLs). The other Smc lineages were not MDR and did not express MBLs. We also obtained isolates related to S. acidaminiphila, S. humi and S. terrae. They were significantly more susceptible to antibiotics than S. maltophilia. We demonstrate that the sympatric lineages recovered display significantly differentiated habitat preferences, antibiotic resistance profiles and beta-lactamase expression phenotypes, as shown by diverse multivariate analyses and robust univariate statistical tests. We discuss our data in light of current models of bacterial speciation, which fit these data well, stressing the implications of species delimitation in ecological, evolutionary and clinical research.

microbiology↗