Biology subjects

Gacesa, R.

Publications and source records attributed to Gacesa, R..

12 recordsLinked to original sources

bioRxiv2026

Extensive genomic diversity in Desulfovibrio species reveals species-specific functional traits associated with disease

Desulfovibrio spp. are associated with inflammatory diseases and human health, yet limited representative genomes and isolates hinder our understanding of their role in disease. Here, we assembled a comprehensive database of 2,658 Desulfovibrio genomes across 90 diseases and 32 countries, including 24 human isolates. Genomic analyses showed extensive species diversity and revealed disease-associated functional traits, including flagellin and virulence genes (i.e. ureases). Flagellin-mediated Toll-like receptor 5 activation was species-specific and D. desulfuricans flagellin downregulated TGF-beta signalling in murine small intestinal organoids, suggesting impaired immune tolerance. Additionally, we investigated genomic capacity for hydrogen sulfide (H2S) production, a main Desulfovibrio metabolite. While health- and disease-associated Desulfovibrio spp. mainly encoded dissimilatory sulfate reduction, tetrathionate metabolism-encoding bacteria were exclusively detected in inflammatory bowel diseases, including Proteus mirabilis and Morganella morganii. Overall, our study provides a comprehensive genomic Desulfovibrio resource and identifies new links associating strain variation, functional traits and H2S-production with inflammatory diseases.

genomics↗

bioRxiv2025

A global genetic interaction map of a human cell reveals conserved principles of genetic networks

We generated a genome-scale, genetic interaction network from the analysis of more than 4 million double mutants in the haploid human cell line, HAP1. The network maps [~]90,000 genetic interactions, including thousands of extreme synthetic lethal and genetic suppression interactions. Genetic interaction profiles enabled assembly of a hierarchical model of cell function, including modules corresponding to protein complexes, pathways, biological processes, and cellular compartments. Comparative analyses showed that general principles of genetic networks are conserved from yeast to human cells. A genetic interaction network mapped in a single genetic background complements the DepMap gene co-essentiality network, recapitulating many of the same biological connections and also capturing unique functional information to reveal roles of uncharacterized genes and molecular determinants of specific cancer cell line genetic dependencies.

systems biology↗

bioRxiv2025

Vaginal microbiota changes during a natural menstrual cycle in the Women4Health cohort highlights specific features of the Italian population.

Large sex hormonal fluctuations are thought to influence vaginal microbiota, but little is known about the impact of small, physiological variations. Here we tracked changes in vaginal microbiota during four key menstrual cycle phases in 61 healthy, naturally menstruating Italian women from the Women4Health cohort. The microbiota, characterized using a high depth 16S rRNA amplicon sequencing approach covering four hypervariable regions, was primarily composed of Lactobacillus species, with Lactobacillus iners being the most abundant (average relative abundance 40%) and the most prevalent (prevalence 98%). Individual microbiota were generally stable, but beta diversity was higher during the follicular phase (p=0.007). Only 11 women exhibited compositional shifts, mostly occurring between follicular and ovulatory phases. Finally, using linear mixed models we assessed the association between taxa relative abundance and five sex-hormones along the menstrual cycle. Among these, 17-beta estradiol showed the largest number of significant associations, linking its increase to a decrease in relative abundance of taxa that are more common after menopause. Our study highlights specific features of the Italian population and points to the resilience of the vaginal microbiota to physiological hormonal changes. Noteworthy, the observed high abundance of L. iners contrasts with previous studies in European populations, challenging its proposed pathogenic role and suggesting distinct microbiota profiles within Europe. IMPORTANCEThe vaginal microbiota plays an important role in womens health, yet we know little about how it responds to normal hormonal fluctuations. In this study, we followed 61 healthy Italian women over a natural menstrual cycle to explore microbiota changes across different hormonal phases. We found that Lactobacillus iners was the most common species, unlike previous findings in Northern Europe, suggesting population-specific patterns. The common hypothesis that L. iners is invariably linked with poor health is called into question by our findings. They emphasize the importance of considering population context and hormonal status when assessing vaginal health. The vaginal microbiota was generally stable, with only a few changes observed between the follicular and ovulatory phases. When evaluating association between five sex hormones and taxa abundances, we found that 17-beta estradiol levels had the largest number of significant associations. These highlight an association between increase levels of 17-beta estradiol and increased relative abundance of rare bacterial taxa rather than dominant species like Lactobacillus. Our findings help define what constitutes a "healthy microbiota" in generally healthy Italian women of reproductive age and may inform future strategies for diagnosing or preventing womens health conditions.

microbiology↗

bioRxiv2024

High-resolution analysis of the treated coeliac disease microbiome reveals increased inter-individual variability

BackgroundCoeliac disease (CeD) is an immune-mediated disorder primarily affecting the small intestine, characterised by an inflammatory immune reaction to dietary gluten. CeD onset results from a multifaceted interplay of genetic and environmental factors. While recent data show that alterations in gut microbiome composition could play an important role, many current studies are constrained by small sample sizes and limited resolution. MethodsTo address these limitations, we analysed faecal gut microbiota from two Dutch cohorts, CeDNN (128 treated CeD patients (tCeD), 106 controls) and the Lifelines Dutch Microbiome Project (24 self-reported tCeD, 654 controls), using shotgun metagenomic sequencing. Self-reported IBS (570 cases, 1710 controls) and IBD (93 cases, 465 controls) were used as comparative conditions of the gastrointestinal tract. Interindividual variation within the case and control groups was calculated at whole microbiome and strain level. Finally, species-specific gene repertoires were analysed in tCeD patients and controls. ResultsWithin-individual microbiome diversity was decreased in patients with self-reported IBS and IBD but not in tCeD patients. Each condition displayed a unique microbial pattern and, in addition to confirming previously reported microbiome associations, we identify an increase in the levels of Clostridium sp. CAG:253, Roseburia hominis, and Eggerthella lenta, amongst others. We further show that the observed changes can partially be explained by gluten-free diet adherence. We also observe increased interindividual variation of gut microbiome composition among tCeD patients and a higher bacterial mutation frequency in tCeD that contributes to higher interindividual variation at strain level. In addition, the immotile European subspecies of Eubacterium rectale, which has a distinct carbohydrate metabolism potential, was nearly absent in tCeD patients. ConclusionOur study sheds light on the complex interplay between the gut microbiome and CeD, revealing increased interindividual variation and strain-level variation in tCeD patients. These findings expand our understanding of the microbiomes role in intestinal health and disease. HighlightsO_LIThis is the largest microbiome collection of coeliac disease (CeD) patients assembled to date, providing insights into gut microbiome composition down to strain level. C_LIO_LICompared to controls, treated CeD (tCeD) patients adhering to a gluten-free diet show novel gut microbiome associations. C_LIO_LItCeD patients also have a less uniform gut microbiome than controls. C_LIO_LIBacteria display higher mutation frequency in tCeD compared to controls. C_LIO_LIHallmarks of the European subspecies of Eubacterium rectale are nearly absent in tCeD patients, implying selection at strain level. C_LI

microbiology↗

bioRxiv2023

Mother-Infant Gut Viruses and their Bacterial Hosts: Transmission Patterns and Dynamics during Pregnancy and Early Life

Early development of the gut ecosystem is crucial for lifelong health. While infant gut bacterial communities have been studied extensively, the infant gut virome remains under-explored. We longitudinally assessed the composition of gut viruses and their bacterial hosts in 322 total metagenomes and 205 metaviromes from 30 mothers during and after pregnancy and from their 32 infants during their first year of life. While the maternal gut virome composition remained stable during late pregnancy and after birth, the infant gut virome was dynamic in the first year of life and contained a higher abundance of active temperate phages compared to the maternal gut viromes. The infant gut virome composition was also influenced by infant feeding mode and place of delivery. Lastly, we provide evidence of viral-bacterial strains co-transmission from mothers to infants, demonstrating that infants acquire some of their virome from their mothers gut. Highlights- Longitudinal characterisation of the gut microbiome and virome in 30 mothers during pregnancy, at birth and 3 months after birth and in 32 infants from birth across the first year of life. - The maternal gut bacteriome changes from the first to the second trimester and then remains stable through birth and the first 3 months after birth. - The maternal gut virome remains stable during late pregnancy, birth and the first 3 months after birth. - The infant gut virome is highly dynamic during the first year of life and is shaped by infant feeding mode and place of delivery. - The infant gut harbours more temperate bacteriophages than the maternal gut, but their relative abundance decreases with increasing infant age. - Gut viral strains and their bacterial host strains are co-transmitted from mothers to their infants. - Gut viral strains are transferred from mother to infant around birth directly or via transfer of their bacterial hosts followed by the induction of prophages.

microbiology↗

bioRxiv2023

The gut microbiome across the cardiovascular risk spectrum

RationaleDespite significant progress in treatment strategies, cardiovascular disease remains a leading cause of death worldwide. Identifying new potential targets is crucial for enhancing preventive and therapeutic strategies. The gut microbiome has been associated with the development of coronary artery disease (CAD), however our understanding of the precise changes in the gut microbiome occurring during CAD development remains limited. ObjectiveTo investigate microbiome changes in participants without clinically manifest CAD with different cardiovascular risk levels and in patients with ST-elevation myocardial infarction (STEMI). Methods and ResultsIn this cross-sectional study we characterized the gut microbiome using metagenomics of 411 fecal samples from individuals with low (n=130), intermediate (n=130) and high (n=125) cardiovascular risk based on the Framingham score, and STEMI patients (n=26). We analyzed alpha and beta diversity of the gut microbiome and differential abundance of species and functional pathways among the different groups while accounting for confounders including medication and technical covariates. Abundances of Collinsella stercoris, Flavonifractor plautii and Ruthenibacterium lactatiformans showed a positive trend with cardiovascular risk, while Streptococcus thermophilus was negatively associated. Furthermore, in the differential abundance analysis we identified eight species and 49 predicted metabolic pathways that were differently abundant among the groups. These species included species linked to inflammation. Starch biosynthesis and phenolic compound degradation pathways were enriched in the gut microbiome of STEMI patients, while pathways associated with vitamin, lipid and amino-acid biosynthesis were depleted. ConclusionsWe identified four microbial species that demonstrated a gradual trend in their abundance from low risk individuals to those with STEMI, and species and pathways that were differently abundant in STEMI patients compared to groups without clinically manifest CAD. Further investigation is warranted to gain deeper understanding of their precise role in CAD progression and potential implications, with the ultimate goal of identifying novel therapeutic targets. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=142 HEIGHT=200 SRC="FIGDIR/small/546971v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@f7f0b1org.highwire.dtl.DTLVardef@1db0c8eorg.highwire.dtl.DTLVardef@154adeorg.highwire.dtl.DTLVardef@1e64c74_HPS_FORMAT_FIGEXP M_FIG C_FIG Created with BioRender.com

genomics↗

bioRxiv2022

The faecal metabolome and its determinants in inflammatory bowel disease

ObjectiveInflammatory bowel disease (IBD) is a multifactorial immune-mediated inflammatory disease of the intestine, comprising Crohns disease and ulcerative colitis. By characterising metabolites in faeces, combined with faecal metagenomics, host genetics and clinical characteristics, we aimed to unravel metabolic alterations in IBD. DesignWe measured 1,684 different faecal metabolites and 8 short-chain and branched-chain fatty acids in stool samples of 424 IBD patients and 255 non-IBD controls. Regression analyses were used to compare concentrations of metabolites between cases and controls and determine the relationship between metabolites and each participants lifestyle, clinical characteristics and gut microbiota composition. Moreover, genome-wide association analysis was conducted on faecal metabolite levels. ResultsWe identified over 300 molecules that were differentially abundant in the faeces of patients with IBD. The ratio between a sphingolipid and L-urobilin could discriminate between IBD and non-IBD samples (AUC = 0.85). We found changes in the bile acid pool in patients with dysbiotic microbial communities and a strong association between faecal metabolome and gut microbiota. For example, the abundance of Ruminococcus gnavus was positively associated with tryptamine levels. In addition, we found 158 associations between metabolites and dietary patterns, and polymorphisms near NAT2 strongly associated with coffee metabolism. ConclusionIn this large-scale analysis, we identified alterations in the metabolome of patients with IBD that are independent of commonly overlooked confounders such as diet and surgical history. Considering the influence of the microbiome on faecal metabolites, our results pave the way for future interventions targeting intestinal inflammation.

microbiology↗

bioRxiv2022

Mucosal host-microbe interactions associate with clinical phenotypes in inflammatory bowel disease

Dysregulation of gut mucosal host-microbe interactions is a central feature of inflammatory bowel disease (IBD). To study tissue-specific interactions, we performed transcriptomic (RNA-seq) and microbial (16S-rRNA-seq) profiling of 696 intestinal biopsies derived from 353 patients with IBD and controls. Analysis of transcript-bacteria interactions identified six distinct groups of inflammation-related pathways that were associated with intestinal microbiota, findings we could partially validate in an independent cohort. An increased abundance of Bifidobacterium was associated with higher expression of genes involved in fatty acid metabolism, while Bacteroides was associated with increased metallothionein signaling. In fibrostenotic Crohns disease, a transcriptional network dominated by immunoregulatory genes associated with Lachnoclostridium bacteria in non-stenotic tissue. In patients using TNF--antagonists, a transcriptional network dominated by fatty acid metabolism genes associated with Ruminococcaceae. Mucosal microbiota composition was associated with enrichment of specific intestinal cell types. Overall, we identify multiple host-microbe interactions that may guide microbiota-directed precision medicine.

microbiology↗

bioRxiv2022

HIV-linked gut dysbiosis associates with cytokine production capacity in viral-suppressed people living with HIV

People living with HIV (PLHIV) are exposed to chronic immune dysregulation, even when virus replication is suppressed by antiretroviral therapy (ART). Given the emerging role of the gut microbiome in immunity, we hypothesized that the gut microbiome may be related to the cytokine production capacity of PLHIV. To test this hypothesis, we collected metagenomic data from 143 ART-treated PLHIV and assessed the ex vivo production capacity of eight different cytokines (IL-1{beta}, IL-6, IL-1Ra, IL-10, IL17, IL22, TNF and IFN-{gamma}) in response to different stimuli. We also characterized CD4+ T cell-counts, HIV reservoir and other clinical parameters. Compared to 190 age- and sex-matched controls and a second independent control cohort, PLHIV showed microbial dysbiosis that was correlated with viral reservoir levels, cytokine production capacity and sexual behavior. Notably, we identified two genetically different P. copri strains that were enriched in either PLHIV or healthy controls. The control-enriched strain was negatively associated with IL-10, IL-6 and TNF production, independent of age, sex and sexual behavior, and positively associated with CD4+ T cell-level, whereas the PLHIV-enriched strain showed no associations. Our findings suggest that modulating the gut microbiome may be a strategy to modulate immune response in PLHIV. Novel PointsO_LIWe identified compositional and functional changes in the gut microbiome of PLHIV that were strongly related to sexual behavior. C_LIO_LIHIV-associated bacterial changes are negatively associated with HIV reservoir. The relative abundance of Firmicutes bacterium CAG 95 and Prevotella sp CAG 5226 both show a negative association with CD4+ T cell-associated HIV-1 DNA. C_LIO_LIPrevotella copri and Bacteroides vulgatus show association with PBMC production capacity of IL-1{beta} and IL-10 that is independent of age, sex, BMI and sexual behavior. C_LIO_LIWe observed two genetically different P. copri strains that are enriched in PLHIV and healthy individuals, respectively. C_LIO_LIThe control-related P. copri strain specifically shows a negative association with IL-10, IL-6 and TNF production and a positive association with CD4+ T cell-level. This suggests it plays a potential protective role in chronic inflammation, which may be related to enrichment of a specific epitope peptide. C_LI

microbiology↗

bioRxiv2021

In-depth characterization of the serum antibody epitope repertoire in inflammatory bowel disease using phage-displayed immunoprecipitation sequencing

Inflammatory bowel diseases (IBD), e.g. Crohns disease (CD) and ulcerative colitis (UC), are chronic immune-mediated inflammatory diseases. A comprehensive overview of an IBD-specific antibody epitope repertoire is, however, lacking. We leveraged a high-throughput phage-displayed immunoprecipitation sequencing (PhIP-seq) workflow to identify antibodies against 344,000 antimicrobial, immune and food antigens in 497 IBD patients as compared to 1,326 controls. IBD was characterized by 373 differentially abundant antibodies (202 overrepresented and 171 underrepresented), with 17% shared by both IBDs, 55% unique to CD and 28% unique to UC. Antibodies against bacterial flagellins dominated in CD and were associated with ileal involvement, fibrostenotic disease and anti-Saccharomyces cerevisiae antibody positivity, but not with fecal microbiome composition. Antibody epitope repertoires accurately discriminated CD from controls (AUC=0.89), and similar discrimination was achieved when using only ten antibodies (AUC=0.87). IBD patients thus show a distinct antibody repertoire against selected peptides, allowing patient stratification and discovery of immunological targets.

immunology↗

bioRxiv2020

Effect of host genetics on the gut microbiome in 7,738 participants of the Dutch Microbiome Project

Host genetics are known to influence the gut microbiome, yet their role remains poorly understood. To robustly characterize these effects, we performed a genome-wide association study of 207 taxa and 205 pathways representing microbial composition and function within the Dutch Microbiome Project, a population cohort of 7,738 individuals from the northern Netherlands. Two robust, study-wide significant (p<1.89x10-10) signals near the LCT and ABO genes were found to affect multiple microbial taxa and pathways, and were replicated in two independent cohorts. The LCT locus associations were modulated by lactose intake, while those at ABO reflected participant secretor status determined by FUT2 genotype. Eighteen other loci showed suggestive evidence (p<5x10-8) of association with microbial taxa and pathways. At a more lenient threshold, the number of loci identified strongly correlated with trait heritability, suggesting that much larger sample sizes are needed to elucidate the remaining effects of host genetics on the gut microbiome.

genetics↗

bioRxiv2020

The Dutch Microbiome Project defines factors that shape the healthy gut microbiome

The gut microbiome is associated with diverse diseases, but the universal signature of an (un)healthy microbiome remains elusive and there is a need to understand how genetics, exposome, lifestyle and diet shape the microbiome in health and disease. To fill this gap, we profiled bacterial composition, function, antibiotic resistance and virulence factors in the gut microbiomes of 8,208 Dutch individuals from a three-generational cohort comprising 2,756 families. We then correlated this to 241 host and environmental factors, including physical and mental health, medication use, diet, socioeconomic factors and childhood and current exposome. We identify that the microbiome is primarily shaped by environment and cohousing. Only [~]13% of taxa are heritable, which are enriched with highly prevalent and health-associated bacteria. By identifying 2,856 associations between microbiome and health, we find that seemingly unrelated diseases share a common signature that is independent of comorbidities. Furthermore, we identify 7,519 associations between microbiome features and diet, socioeconomics and early life and current exposome, of which numerous early-life and current factors are particularly linked to the microbiome. Overall, this study provides a comprehensive overview of gut microbiome and the underlying impact of heritability and exposures that will facilitate future development of microbiome-targeted therapies.

microbiology↗