Search bioRxiv⌕ Search

Biology subjects

Morabito, C.

Publications and source records attributed to Morabito, C..

6 recordsLinked to original sources

Hydrogen metabolism shapes gut microbiome into health-associated configurations

The human gut microbiome exhibits reproducible configurations, yet the ecological forces connecting them to health remain unclear. Here, using enterosignature-based stratification of 5,170 individuals from the Le French Gut cohort, we identified hydrogen disposal as a key determinant of population-scale microbiome configurations, independently replicated in a meta-cohort (n = 5,107). Microbial configurations followed a continuum of hydrogen recycling capacity and redox-associated functions, aligned with dietary patterns and health indicators. Methanogenesis-dominant partitions were associated with more favorable health profiles, whereas acetogenesis-enriched partitions exhibited features of low-grade inflammation, and increased digestive symptoms, perceived stress and antidepressant use. Experimental characterization of mucin profiles highlighted differences across partitions and alterations in Bacteroides-enriched configurations. Together, our findings support an ecological host-microbiome framework linking hydrogen metabolism, redox ecology, and host health, offering microbiome-informed targets for precision intervention. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=128 SRC="FIGDIR/small/722951v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@e7b8d1org.highwire.dtl.DTLVardef@116ab09org.highwire.dtl.DTLVardef@136f1f8org.highwire.dtl.DTLVardef@480097_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Progressive drought transcriptomics and co-expression framework in eggplant (Solanum melongena L.)

Drought is a major constraint for eggplant productivity in Mediterranean and semi-arid environments, yet stage-specific molecular features that distinguish tolerant and sensitive genotypes under progressive water deficit remain limited. Here, we profiled drought responses in two contrasting eggplant (Solanum melongena L.) genotypes from the G2P-SOL core collection, integrating physiology and transcriptomics to resolve genotype-dependent programs at moderate and severe stress. Physiological measurements confirmed divergent drought performance, with the tolerant genotype Berenjena de rabo largo (GPE020510) maintaining water status and stomatal function longer than the sensitive genotype Qianzi (GPE008940). RNA-seq revealed strong transcriptional reprogramming in both genotypes, but with distinct timing and functional priorities across stress transitions. At moderate stress, tolerance was associated with early ABA-centred regulatory control and dehydration protection (including ABI5, TAS14 and LEA/dehydrin-related loci), coupled to transport and redox homeostasis and repression of growth-associated outputs. In contrast, the sensitive genotype showed prominent early regulatory and RNA/protein-turnover signatures alongside weaker representation of cuticle/barrier and chloroplast/light-management functions. Under severe stress, the sensitive genotype shifted toward a broad high-maintenance state enriched in remodeling, detoxification and transporter activity, whereas the tolerant genotype displayed a more targeted adjustment featuring plastid photoprotection, proteostasis and selective metabolic reconfiguration. Co-expression network analysis supported this stage-resolved model by identifying modules and hub genes with contrasting temporal trajectories between genotypes, linking earlier coordinated regulatory/membrane-trafficking and plastid/redox tuning to drought tolerance. Overall, these results indicate that eggplant drought resilience is associated with genotype-specific coordination and timing of protective programs superimposed on a shared basal stress response, and they provide prioritized candidate pathways and genes for functional validation and breeding.

plant biology↗

Long-term salinity reveals genotype-specific transcriptional reprogramming in eggplant

Salinity severely limits eggplant productivity, yet the transcriptional bases of tolerance to prolonged salt exposure remain incompletely understood. Here, we analyzed long-term salinity responses in two contrasting eggplant (Solanum melongena L.) genotypes from the G2P-SOL core collection, focusing on genotype-dependent transcriptional regulation under chronic stress. Plants were exposed to 200 mM NaCl for 23 days at the reproductive stage, and transcriptome profiling was performed at the end of the stress period. Physiological assessment and high-throughput phenotyping confirmed a strong divergence in water status and plant architecture between genotypes under salinity, providing a reference framework for transcriptomic interpretation. RNA-seq analysis revealed marked genotype-specific differences in transcriptional responses. While both genotypes activated a conserved salt-stress program involving redox homeostasis, proteostasis and growth repression, the tolerant genotype displayed a substantially broader and more coordinated transcriptional reprogramming. This response involved large-scale modulation of pathways related to translation and RNA metabolism, hormone signaling crosstalk, membrane transport, cell wall remodeling and oxidative stress management, together with the selective repression of growth- and signaling-related functions. In contrast, the sensitive genotype showed a more limited response dominated by defense- and damage-associated transcripts. Overall, these results indicate that long-term salt tolerance in eggplant is associated with genotype-specific transcriptional reprogramming superimposed on a shared basal stress response. This work highlights regulatory pathways and candidate genes potentially relevant for breeding strategies targeting salt resilience.

plant biology↗

Exploring the relationship between GBA1 host genotype and gut microbiome in the GBA1L444P/WT mouse model: Implications for Parkinson disease pathogenesis

BackgroundHeterozygous variants in GBA1 are the commonest genetic risk factor for Parkinson disease (PD) but penetrance is incomplete. GBA1 dysfunction can cause gastrointestinal disturbances and microbiome changes in preclinical models. Mounting evidence suggests that the microbiota-gut-brain axis is potentially implicated in PD pathogenesis. Whether the gut microbiome composition is influenced by host GBA1 genetics in heterozygosis has never been explored. ObjectivesTo evaluate whether heterozygosity for the GBA1 pathogenic L444P variant can cause perturbations in gut microbiome composition. MethodsFaecal samples collected from GBA1L444P/WT and GBA1WT/WT mice at 3 and 6 months of age were analysed through shotgun metagenomic sequencing. ResultsNo differences in - and {beta}-diversity were detected between genotyped groups, at either time points. Overall, we found a little variation of the gut microbiome composition and functional potential between GBA1L444P/WT and GBA1WT/WT mice over time. ConclusionHost GBA1 genotype does not impact gut microbiome structure and composition in the presented GBA1L444P/WT mouse model. Studies investigating the effect of a second hit on gut physiology and microbiome composition could explain the partial penetrance of GBA1 variants in PD.

neuroscience↗

In vitro modelling of oral microbial invasion in the human colon

Recent advances in the human microbiome characterization have revealed significant oral microbial detection in stools of dysbiotic patients. However, little is known about the potential interactions of these invasive oral microorganisms with commensal intestinal microbiota and host. In this proof of concept study, we propose a new model of oral to gut invasion by the combined use of an in vitro model simulating both the physicochemical and microbial (lumen and mucus-associated microbes) parameters of the human colon (M-ARCOL), a salivary enrichment protocol and whole metagenome shotgun sequencing. Oral invasion of the intestinal microbiota was simulated by injection of enriched saliva in the in vitro colon model inoculated with faecal sample from the same healthy adult donor. The mucosal compartment of M-ARCOL was able to retain the highest species richness levels over time, whilst it decreased in the luminal compartment. This study also showed that oral microorganisms preferably colonized the mucosal microenvironment, suggesting potential oral-to-intestinal mucosal competitions. This new model of oral-to-gut invasion can provide useful mechanistic insights into the role of oral microbiome in various disease processes.

microbiology↗

Diversity Converges During Community Assembly In Methanogenic Granules, Suggesting A Biofilm Life-Cycle

Anaerobic biological decomposition of organic matter is ubiquitous in Nature wherever anaerobic environments prevail, and is catalysed by hydrolytic, fermentative, acetogenic, methanogenic, and various other groups, including syntrophic bacteria. It is also harnessed in innovative ways in engineered systems that may rely on small (0.1-4.0 mm), spherical, anaerobic granules, which we have found to be highly-replicated, whole-ecosystems harbouring the entire community necessary to mineralise complex organics. We hypothesised distinct granule sizes correspond to stages in a biofilm life-cycle, in which small granules are young and larger ones are old. Here, granules were separated into 10 size fractions used for physico-chemical and ecological characterisation. Gradients of volatile solids, density, settleability, biofilm morphology, methanogenic activity, and EPS profiles were observed across size fractions. Sequencing of 16S rRNA genes indicated linear convergence of diversity during community assembly as granules increased in size. A total of 155 discriminant OTUs were identified, and correlated strongly with physico-chemical parameters. Community assembly across sizes was influenced by a niche effect, whereby Euryarchaeota dominated a core microbiome presumably as granules became more anaerobic. The findings indicate opportunities for precision management of environmental biotechnologies, and the potential of aggregates as playgrounds to study assembly and succession in whole microbiomes.

microbiology↗