Project description:The intestinal microbiota plays a key role in shaping host homeostasis by regulating metabolism, immune responses and behaviour. Its dysregulation has been associated with metabolic, immune and neuropsychiatric disorders and is accompanied by changes in bacterial metabolic regulation. Although proteomic is well suited for analysis of individual microbes, metaproteomic of faecal samples is challenging due to the physical structure of the sample, presence of contaminating host proteins and coexistence of hundreds of species. Furthermore, there is a lack of consensus regarding preparation of faecal samples, as well as downstream bioinformatic analyses following metaproteomic data acquisition. Here we assess sample preparation and data analysis strategies applied to mouse faeces in a typical LC-MS/MS metaproteomic experiment. We show that low speed centrifugation (LSC) of faecal samples leads to high protein identification rates but possibly enriched for a subset of taxa. During database search, two-step search strategies led to dramatic and underestimated accumulation of false positive protein identifications. Regarding taxonomic annotation, the MS-identified peptides of unknown origin were annotated with highest sensitivity and specificity using the Unipept software. Comparison of matching metaproteome and metagenome data revealed a positive correlation between protein and gene abundances. Notably, nearly all functional categories of detected protein groups were differentially abundant in the metaproteome compared to what would be expected from the metagenome, highlighting the need to perform metaproteomic when studying complex microbiome samples.
2022-02-17 | PXD027306 | Pride
Project description:Temporal variation of the horse faecal microbiota
| PRJNA523943 | ENA
Project description:Shotgun Metagenome and 16-S Sequencing of Horse Faecal and Nasal Swab Samples
Project description:RNAseq and LC/MS metabolomics analysis of C. difficile strain 630 grown in BHIS media with 50% (vol/vol) faecal water added, compared with control BHIS containing only the additional PBS used for prep of Faecal water. Cells grown in biological triplicates to late log phase (T=6h) prior to harvest. Goal was to determine changes in gene expression caused by exposure to Faecal water, and changes in the metabolite profile of faecal water containing medium when incubated with actively growing C. difficile cells
Project description:<p><strong>OBJECTIVE:</strong> Rheumatoid arthritis (RA) is a progressive disease including four stages, where gut microbiome is associated with pathogenesis. We aimed to investigate stage-specific roles of microbial dysbiosis and metabolic disorders in RA.</p><p><strong>METHODS:</strong> We investigated stage-based profiles of faecal metagenome and plasma metabolome of 76 individuals with RA grouped into four stages (stages I-IV) according to 2010 RA classification criteria, 19 individuals with osteroarthritis and 27 healthy individuals. To verify bacterial invasion of joint synovial fluid, 16S rRNA gene sequencing, bacterial isolation and scanning electron microscopy were conducted on another validation cohort of 271 patients from four RA stages.</p><p><strong>RESULTS:</strong> First, depletion of <em>Bacteroides uniformis</em> and <em>Bacteroides plebeius</em> weakened glycosaminoglycan metabolism (p<0.001), continuously hurting articular cartilage across four stages. Second, elevation of <em>Escherichia coli</em> enhanced arginine succinyltransferase pathway in the stage II and stage III (p<0.001), which was correlated with the increase of the rheumatoid factor (p=1.35 x 10^-3) and could induce bone loss. Third, abnormally high levels of methoxyacetic acid (p=1.28 x 10^-8) and cysteine-S-sulfate (p=4.66 x 10^-12) inhibited osteoblasts in the stage II and enhanced osteoclasts in the stage III, respectively, promoting bone erosion. Fourth, continuous increase of gut permeability may induce gut microbial invasion of the joint synovial fluid in the stage IV.</p><p><strong>CONCLUSIONS:</strong> Clinical microbial intervention should consider the RA stage, where microbial dysbiosis and metabolic disorders present distinct patterns and played stage-specific roles. Our work provides a new insight in understanding gut-joint axis from a perspective of stages, which opens up new avenues for RA prognosis and therapy.</p>