Laboratoire / Institut : ICSN-CNRS

Equipe de recherche : Chimie fonctionnelle- Ecologie chimique

Nom du responsable d’équipe : Dr Eparvier Véronique

Encadrants du stage : Drs Eparvier Véronique1 & Touboul David2

Courriel de l’encadrant : veronique.eparvier@cnrs.fr ; david.touboul@cnrs.fr

Adresse du Laboratoire : 1- ICSN, av de la terrasse 91190 Gif sur Yvette 2- LCM, Ecole Polytechnique, Palaiseau

Title of internship topic: Chemotaxonomic Exploration of the Macro and Micromycetes Xylariales of French Guiana

Summary

Fungi, which are ubiquitous in all environments, play a key role in ecological processes as decomposers and producers of specialised metabolites. These metabolites, used for communication and defence, are of major interest for bioprospecting (medicine, agriculture, biotechnology). Traditionally, fungal species identification has relied on morphological and phylogenetic (ITS) markers, but chemotaxonomy—classification based on metabolic profiles—remains under-explored, despite its potential for fine-grained classification. Recent advances in molecular networking and high-resolution mass spectrometry (HRMS/MS) now enable large-scale analyses, paving the way for in-depth chemotaxonomic studies.

Objectives

  • To extend chemotaxonomy to micro- and macromycetes by identifying unique metabolic markers.
  • To analyse chemical variability according to environmental conditions, developmental stages and preservation methods.
  • Develop reliable chemical markers for classification, reducing dependence on ITS sequencing.
  • Integrate modern analytical tools (LC-MS/MS, molecular networks) for large-scale metabolomic analyses.
  • Discover new metabolites with potential applications in taxonomy and natural product research.

Required skills

  • Analytical chemistry: Extraction and purification of extracts from microorganisms, preparation of samples for SM, NMR, HPLC, RX analyses, etc.
  • Metabolomics: Proficiency in LC-MS/MS, high-resolution mass spectrometry, data processing software (MzMine, MetGem, GNPS), molecular network analysis, metabolite annotation, use of metabolomic databases.
  • Fungal taxonomy: Knowledge of phylogenetic markers (ITS), morphological and molecular identification methods.
  • Scientific communication: presentation of results.
  • Skills in monitoring laboratory experiments and data analysis.
  • Enjoy working in a team, motivated, rigorous and proactive.

LC-MS/MS experiments and data analysis will be carried out by Dr. David Touboul’s team at the Molecular Chemistry Laboratory, UMR 9168, Ecole Polytechnique.

References

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  • S. E. Helaly, H. T. Thongbai, S. Stadler, Indole derivatives from Xylariales: Bioactive secondary metabolites as taxonomic markers. Stud. Mycol. 89, 147–174 (2018). DOI: 10.1016/j.simyco.2018.02.003
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  • L. F. Nothias, P. Petras, J. M. Schmid, Feature-based molecular networking in the GNPS analysis environment. Nat. Methods 17, 905–908 (2020). DOI: 10.1038/s41592-020-0933-6
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  • J. Fournier, C. Lechat, Contribution to the taxonomy of some Xylaria species from French Guiana. Ascomycete.org 7, 69–86 (2015). DOI: 10.25664/art- 0185