The triennial European Conference on Natural Products (ECNP) is an international platform where experts from Europe, Asia and the U.S. present recent advances from all fields in secondary metabolite research.

Marie Dayras Postdoctoral researcher at Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Saarbrücken, Germany.

Can you tell us a bit about yourself and your research interests?

I obtained my B.Sc. in Chemistry from the University of Clermont Auvergne, France. This was followed in 2016 by an M.Sc. in Formulation, Quality and Analysis at the University Côte d’Azur, France. I then joined the group of Marine Natural Products at Institute of Chemistry of Nice, where I received my PhD in Chemistry in June 2022. After a postdoctoral stay, I joined the group of Prof. Christine Beemelmanns in January 2023. My research focuses on the chemical study of microorganisms to characterize new natural products of biological interest.

What first interested you in this field of research?

The spread of antibiotic-resistant human pathogenic microorganisms poses an increasing threat to human health, and the development of new anti-infective agents and a better understanding of their function and mode of action is urgently needed. My field of research pursues a microbiota-based strategy to identify new active substances from microorganisms that could be used at new anti-infective agents.

Can you briefly explain the research you presented at the 5th ECNP?

Fungus-farming termites are amongst the best studied examples for microbial co-evolution and defensive symbioses, and OMICs-based analyses have revealed the enormous biosynthetic ability of microbial symbionts leading to the discovery of many new chemical scaffolds with important ecological and pharmacological properties. In this context, our metabolomic analysis showed that co-evolved garden parasite Pseudoxylaria secretes diffusible bioactive and structurally unique fungal natural products as exemplified by the targeted isolation of cytochalasin family. Despite the abundance and diversity of cytochalasans with more than 300 known structures reported until today, fundamental biochemical and ecological understanding about their functions, biosynthetic regulations and cellular targets other than actin is still lacking. The same observation is made with internal or external triggers that could activate cryptic cytochalasin-related BGCs productions and would reveal more about their ecological roles. In our study, co-cultivation set-ups of Pseudoxylaria with bacterial symbionts have revealed an increase in the production of known and new cytochalasans. Moreover, feeding experiments have demonstrated the ability of Pseudoxylaria to incorporate many different substituted aromatic amino acids into the cytochalasin leading to the isolation of novel derivatives with potentially altered bioactivities-backbone.

How will you continue to build on this research?

The resulting natural products are currently evaluated to better understand their structure-activity relationships and advance the profiling of the most promising candidates. Moreover, the help of this study, we hope to be able to make better statements about the dynamics of microbial communities. The elucidation of the biosynthetic pathways of new natural products and their regulation is also an important part of our research in order to improve our biocatalytic understanding and advance the development of biotechnological approaches.