Ecological role and biosynthesis of coffee seed diterpenes

Antoine Gaëlle, Vaissayre Virginie, Meile Jean-Christophe, Payet Jim, Conejero Geneviève, Costet Laurent, Fock-Bastide Isabelle, Frey Maximilian, Bathe Ulschan, Tissier Alain, Joët Thierry, Dussert Stéphane. 2022. Ecological role and biosynthesis of coffee seed diterpenes. . IRIG. Grenoble : IRIG, Résumé, 1 p. International Symposium on Plants Lipids (ISPL2022). 25, Grenoble, France, 10 Juillet 2022/15 Juillet 2022.

Résumé : Species of the genus Coffea accumulate diterpenes of the ent-kaurane family in the endosperm of their seeds, of which cafestol and kahweol are the most abundant (ca. 1-2% DW). In contrast to the numerous studies on their effects on human health and therapeutic applications, nothing was previously known about their biological and ecological role in planta. The antifungal and anti-insect activity of cafestol was thus investigated in this study. Cafestol significantly affected the mycelial growth of five of the six phytopathogenic fungi tested. It also greatly reduced the percentage of pupation of larvae and the pupae and adult masses of one of the two fruit flies tested. Using confocal imaging and oil body isolation and analysis, we showed that diterpenes are localized in endosperm oil bodies. Diterpene measurements in all organs of seedlings recovered from whole seed germination or embryos isolated from the endosperm showed that diterpenes are transferred from the endosperm to the cotyledons during seedling growth and then distributed to all organs, including the hypocotyl and the root. Collectively, our findings show that coffee diterpenes are broad-spectrum defence compounds that protect not only the seed on the mother plant and in the soil, but also the seedling after germination. Furthermore, the genes and enzymes involved in the biosynthesis of cafestol and kahweol remain unknown. Phylogenetic analyses were first performed to identify and classify all terpene synthases and cytochromes P450 (CYPs) in the coffee genome. Then, using a large transcriptome dataset (14 species and 5 seed developmental stages per species) and genes coding for the enzymes that catalyze the synthesis of ent-kaurenoic acid as guide genes, seven candidate CYP genes were identified through gene coexpression network analysis. Their role in cafestol and kahweol biosynthesis is currently investigated using heterologous expression in yeast and tobacco in combination with GC- and LC-MS analysis.

Auteurs et affiliations

• Antoine Gaëlle, Université de la Réunion (REU)
• Vaissayre Virginie, IRD (FRA)
• Meile Jean-Christophe, CIRAD-PERSYST-UMR Qualisud (FRA) ORCID: 0000-0002-6747-2104
• Payet Jim, CIRAD-BIOS-UMR PVBMT (REU)
• Conejero Geneviève, INRAE (FRA)
• Costet Laurent, CIRAD-BIOS-UMR PVBMT (REU) ORCID: 0000-0003-3199-2885
• Fock-Bastide Isabelle, Université de la Réunion (REU)
• Frey Maximilian, Leibniz Institute of Plant Biochemistry (DEU)
• Bathe Ulschan, Leibniz Institute of Plant Biochemistry (DEU)
• Tissier Alain, Leibniz Institute of Plant Biochemistry (DEU)
• Joët Thierry, IRD (FRA)
• Dussert Stéphane, IRD (FRA)

Source : Cirad-Agritrop (https://agritrop.cirad.fr/606486/)

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