Biology subjects

Pible, O.

Publications and source records attributed to Pible, O..

4 recordsLinked to original sources

bioRxiv2024

Key gut microbiota components and functions in an aquatic keystone species across diets assessed by metaproteomics

The gut microbiota plays a crucial role in maintaining host fitness and modulating contaminant toxicity-related responses. However, information on how the gut microbiota of sentinel species responds to environmental factors is limited. In this study, we characterized the gut microbial community and its functions under normal, contaminant-free conditions by examining the effects of different diets over a 10-day period (alder leaf, carrot, spinach, and protein-rich granules) on the amphipod Gammarus fossarum, commonly used in bioassays for ecotoxicity assessment of contaminated rivers. Metaproteomic analysis of intestine samples enabled taxonomic characterization of the gut microbiota from this millimetric animal, assignment of biological functions to each microbial entity, and functional analysis of host proteins. The most abundant microbes detected in the gut belong to 37 bacterial and 5 fungal genera. Functional analyses of host and microbial proteins revealed complementary metabolic activities, allowing the degradation of complex polysaccharides such as cellulose and chitin. Diet was found to shape microbial community structure, with foodborne microorganisms strongly influencing structural changes during short-term feeding in amphipods. These microorganisms remained viable post-ingestion and contributed to food digestion. Functional stability was maintained across different diets, although the protein-rich granules diet induced functional shifts in both the host and its microbiota, reflecting their adaptation to a novel nutrient source. Finally, we identified a core microbiota driving key gut functions, less affected by dietary variations. These findings are significant for future ecotoxicological and biomonitoring investigations, leveraging the microbiomes of these sentinel animals as pivotal targets.

molecular biology↗

bioRxiv2021

Critical Assessment of Metaproteome Investigation (CAMPI): a Multi-Lab Comparison of Established Workflows

Metaproteomics has matured into a powerful tool to assess functional interactions in microbial communities. While many metaproteomic workflows are available, the impact of method choice on results remains unclear. Here, we carried out the first community-driven, multi-laboratory comparison in metaproteomics: the critical assessment of metaproteome investigation study (CAMPI). Based on well-established workflows, we evaluated the effect of sample preparation, mass spectrometry, and bioinformatic analysis using two samples: a simplified, laboratory-assembled human intestinal model and a human fecal sample. We observed that variability at the peptide level was predominantly due to sample processing workflows, with a smaller contribution of bioinformatic pipelines. These peptide-level differences largely disappeared at the protein group level. While differences were observed for predicted community composition, similar functional profiles were obtained across workflows. CAMPI demonstrates the robustness of present-day metaproteomics research, serves as a template for multi-laboratory studies in metaproteomics, and provides publicly available data sets for benchmarking future developments.

microbiology↗

bioRxiv2020

Proteotyping SARS-CoV-2 virus from nasopharyngeal swabs: a proof-of-concept focused on a 3 min mass spectrometry window

Rapid but yet sensitive, specific and high-throughput detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in clinical samples is key to diagnose infected people and to better control the spread of the virus. Alternative methodologies to PCR and immunodiagnostic that would not require specific reagents are worth to investigate not only for fighting the COVID-19 pandemic, but also to detect other emergent pathogenic threats. Here, we propose the use of tandem mass spectrometry to detect SARS-CoV-2 marker peptides in nasopharyngeal swabs. We documented that the signal from the microbiota present in such samples is low and can be overlooked when interpreting shotgun proteomic data acquired on a restricted window of the peptidome landscape. Simili nasopharyngeal swabs spiked with different quantities of purified SARS-CoV-2 viral material were used to develop a nanoLC-MS/MS acquisition method, which was then successfully applied on COVID-19 clinical samples. We argue that peptides ADETQALPQR and GFYAQGSR from the nucleocapsid protein are of utmost interest as their signal is intense and their elution can be obtained within a 3 min window in the tested conditions. These results pave the way for the development of time-efficient viral diagnostic tests based on mass spectrometry.

microbiology↗

bioRxiv2020

Shotgun proteomics of SARS-CoV-2 infected cells and its application to the optimisation of whole viral particle antigen production for vaccines

Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) has resulted in a pandemic and continues to spread quickly around the globe. Currently, no effective vaccine is available to prevent COVID-19 and an intense global development activity is in progress. In this context, the different technology platforms face several challenges resulting from the involvement of a new virus still not fully characterised. Finding of the right conditions for virus amplification for the development of vaccines based on inactivated or attenuated whole viral particles is among them. Here, we describe the establishment of a workflow based on shotgun tandem mass spectrometry data to guide the optimisation of the conditions for viral amplification. In parallel, we analysed the dynamic of the host cell proteome following SARS-CoV-2 infection providing a global overview of biological processes modulated by the virus and that could be further explored to identify drug targets to address the pandemic.

microbiology↗