Project description:Gut microbiome research is rapidly moving towards the functional characterization of the microbiota by means of shotgun meta-omics. Here, we selected a cohort of healthy subjects from an indigenous and monitored Sardinian population to analyze their gut microbiota using both shotgun metagenomics and shotgun metaproteomics. We found a considerable divergence between genetic potential and functional activity of the human healthy gut microbiota, in spite of a quite comparable taxonomic structure revealed by the two approaches. Investigation of inter-individual variability of taxonomic features revealed Bacteroides and Akkermansia as remarkably conserved and variable in abundance within the population, respectively. Firmicutes-driven butyrogenesis (mainly due to Faecalibacterium spp.) was shown to be the functional activity with the higher expression rate and the lower inter-individual variability in the study cohort, highlighting the key importance of the biosynthesis of this microbial by-product for the gut homeostasis. The taxon-specific contribution to functional activities and metabolic tasks was also examined, giving insights into the peculiar role of several gut microbiota members in carbohydrate metabolism (including polysaccharide degradation, glycan transport, glycolysis and short-chain fatty acid production). In conclusion, our results provide useful indications regarding the main functions actively exerted by the gut microbiota members of a healthy human cohort, and support metaproteomics as a valuable approach to investigate the functional role of the gut microbiota in health and disease.
Project description:The link between the gut microbiota and the human physiological state has been demonstrated in recent years. High gut microbiota diversity has been linked to many beneficial functions necessary or human health, while dysbiosis has been correlated to different pathological states. In this context, the study of the gut microbiota results of high relevance been necessary the development of different techniques capable of characterizing this complex ecosystem. Metaproteomics has been proved useful in the characterization of complex protein samples becoming a suitable tool for the study of these microbial communities. However, due to the complexity of these samples, protein extraction protocols may affect metaproteomics results. In this context, we evaluated stool sample processing (SSP) and microbial cell disruption, assessing the impact of different protocol modifications in the number of peptides and proteins identified. We compared different stool processing conditions and microbial cell disruption methods in terms of protein and peptide identifications and taxonomic profiles.
Project description:We recruited 24 Mongolian volunteers,6 of which were T2D cases(sample T1-T6), 6 were prediabetes cases(sample P1-P6), and 12 were health cases(sample C1-C12). The metagenomic analysis of gut microbiota from the volunteers’ fecal samples was performed. We compared the microbial differences in the three groups, and analyzed the differences of the stool microbial function.