This page is dedicated to my academic works and research. It is in french since that’s the language I had to submit my papers in. Maybe in the future I’ll translate them into english.
Date of submission: 06/01/2026
Analysis of urea induced denaturation of β-galactosidase using R software
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Analysis of urea induced denaturation of β-galactosidase using R software
Date of submission: 6 January 2026
ABSTRACT
β-galactosidase is a widely used enzyme whose catalytic activity depends on the integrity of its three-dimensional structure. In this study, the effect of urea-induced denaturation on β-galactosidase was investigated using kinetic and thermodynamic modeling approaches implemented in R. Enzyme denaturation was first monitored by fluorimetry at 20 °C, following changes in intrinsic fluorescence over time at increasing urea concentrations. The data were fitted to a first-order exponential decay model to estimate apparent denaturation rate constants. Enzymatic activity was then assessed by measuring the hydrolysis of o-nitrophenyl-β-D-galactopyranoside (ONPG) via spectrophotometry, and the dependence of initial reaction rates on urea concentration was modeled using a decreasing exponential function. Finally, a two-state thermodynamic denaturation model was applied to fluorescence data to estimate the Gibbs free energy of unfolding and the denaturant dependence parameter. While urea exposure resulted in a clear reduction of enzymatic activity and alterations in fluorescence signals, the extracted kinetic parameters showed high variability and no consistent dependence on urea concentration. Moreover, the two-state thermodynamic model yielded physically inconsistent parameters, reflecting the complex, multimeric nature of β-galactosidase and the presence of multiple unfolding intermediates. Overall, this study highlights both the usefulness and the limitations of mathematical modeling for enzyme denaturation analysis and emphasizes the critical importance of selecting models that match the structural and mechanistic properties of the enzyme under investigation.
Date of submission: 05/01/2026
Analysis of PBMCs using flow cytometry
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Analysis of PBMCs using flow cytometry
Date of submission: 5 January 2026
ABSTRACT
Peripheral blood mononuclear cells (PBMCs) are key components of the immune system and are widely used as a model to study immune responses. In this study, PBMCs were isolated from human peripheral blood using Ficoll density gradient centrifugation and analyzed through manual cell counting and flow cytometry. Cell concentration was first estimated using a Malassez counting chamber to adjust samples for cytometric analysis. Phenotypic characterization was then performed by flow cytometry using fluorescently labeled antibodies targeting CD45, CD3, CD19, and CD4 markers. Leukocytes were identified based on CD45 expression and low side scatter, allowing discrimination of lymphocytes from other events. Within the lymphocyte population, B cells (CD19⁺) and T cells (CD3⁺) were distinguished, and CD4⁺ T helper cells were quantified among CD3⁺ cells. Results showed a predominance of CD19⁺ B lymphocytes and a majority of CD4⁺ cells within the T-cell population, consistent with expected peripheral blood distributions. However, a high proportion of platelets and cellular debris was observed, limiting the number of lymphocyte events and reducing quantitative accuracy. Despite these technical limitations, the study confirms the effectiveness of Ficoll separation combined with flow cytometry for qualitative phenotypic analysis of PBMCs and highlights the importance of careful sample handling to ensure optimal purity and reliability.
Analysis of the gene ARHGAP11B
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Analysis of the Gene ARHGAP11B
Date of submission: 04/5/2025
ABSTRACT
Since prehistoric times, the brain of the Homo genus has undergone significant development, notably with the emergence of the neocortex, a structure associated with higher cognitive functions such as language and abstract thinking. One gene, ARHGAP11B, specific to humans due to a partial duplication event, has been identified as playing a key role in the amplification of basal progenitor cells, particularly basal radial glial cells. These cells are essential for the expansion of the neocortex during fetal development and are believed to contribute to the emergence of advanced cognitive abilities. In this project, ARHGAP11B was studied in silico to explore how its genetic variations may influence cortical development and what this implies for human evolution and neurodevelopmental disorders. Using bioinformatics tools, we analyzed the gene’s structure (exons, introns), coding sequence, and protein product, and identified its cellular localization and biological function. We also compared the human ARHGAP11B sequence with isoforms found in other primates (Pan troglodytes and Pongo abelii) through sequence alignment and phylogenetic tree construction. Our results confirm a strong similarity between these species, while also highlighting the unique features of the human variant. This study lays the groundwork for future exploration of how evolutionary genetic changes may have shaped human intelligence.
Molecular cloning of Vitellogenin coding DNA
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Molecular cloning of Vitellogenin coding DNA
Date of submission: 16/4/2025
ABSTRACT
Vitellogenin (Vtg), a precursor of yolk proteins, is widely used as a biomarker for xenoestrogenic contamination in aquatic environments. In the Pacific oyster (Crassostrea gigas), Vtg expression has been linked to exposure to nonylphenol and other endocrine-disrupting pollutants. This study aimed to clone the cDNA encoding Vtg from C. gigas using molecular cloning techniques. Plasmid DNA was extracted from E. coli cells harboring a recombinant pGEM-T Easy vector containing oyster Vtg cDNA. The plasmid was then enzymatically digested with EcoRI and analyzed by gel electrophoresis. Concurrently, the cDNA insert was amplified by PCR using specific primers, and the product was verified by agarose gel electrophoresis. Competent E. coli DH5α cells were transformed with the recombinant plasmid, and successful transformants were selected on LB/agar plates containing ampicillin. Colony growth confirmed the presence of the plasmid, and transformation efficiency was estimated at 56,000 colonies/μg DNA. Spectrophotometric analysis indicated high DNA yield with minor RNA contamination. This project demonstrates key steps of molecular cloning and establishes a foundation for future expression and analysis of Vtg in response to endocrine disruptors.
Eason's Experiments 