Two researchers from The Interactions Arbres-Microorganismes Department at Lorraine University, France, will give an Evogene extra seminar.
Eric Gelhaye:
From fungal detoxification systems to tree ecological traits
Abstract: Organisms and in particular static (no-motile) organisms have to be adapted to their environment to cope with biotic and abiotic stresses. In the case of wood-decaying fungi, these latter have developed an efficient detoxification system with expended multigenic families, such as cytochrome P450 monooxygenases and glutathione transferases (GSTs), involved in the catabolism/detoxification of wood extractives. Concerning GSTs, their activity or even their expression are widely used to evaluate physiological and environmental stress of diverse organisms.
In this context, we postulated that fungal GSTs could be used as tools to identify wood extracts that possess interesting biological properties and could also give some clues on the ecological traits of the corresponding trees. We have therefore developed biochemical tests quantifying the interactions between fungal GSTs and wood extracts from subtropical and temperate forests. The obtained results that validate the initial hypothesis and demonstrate a correlation between these interactions and the natural durability of the tested woods as well as the growth strategy (heliophilic/sciaphilic continuum) of the considered species will be discussed.
Read more about his research (Inra)
Mélanie Morel-Rouhier:
Oak extractive-induced stress reveals the involvement of new enzymes in the detoxification response of Phanerochaete chrysosporium
Abstract: Extensive evidence showed that the efficiency of fungal wood degradation is closely dependent on their ability to cope with the myriad of putative toxic compounds called extractives released during this process. By analyzing global gene expression of Phanerochaete chrysosporium after oak extractive treatment (1, 3, 6 and 24h), we show that the early molecular response of the fungus concerns first mitochondrial stress rescue followed by the oxidation and finally conjugation of the compounds. During the early responses, the lignolytic degradative system is not induced, rather some small secreted proteins (SSP) could play an important role in cell protection or signaling.
By focusing on the functional characterization of two uncharacterized glutathione transferases, we show that one of them interacts with wood molecules suggesting that it could (i) be involved in the detoxification of some of them, (ii) act as a scavenger to prevent their cytosolic toxicity and favor their transport or (iii) be a target for these antifungal compounds decreasing the efficiency of the detoxification system. The second one, which is specific to wood degraders, rather acts later as reducing oxidative stress by acting on complex peroxides. These data open interesting perspectives for using these wood molecules as biocides to protect wood material or optimizing conditions for lignocellulosic biomass valorization.
Read more about her research (Inra)
Related articles:
- Deroy et al. (2015) The GSTome Reflects the Chemical Environment of White-Rot Fungi. PLOS ONE. DOI: 10.1371/journal.pone.0137083
- Schwartz et al. (2018) Molecular recognition of wood polyphenols by phase II detoxification enzymes of the white rot Trametes versicolor. Scientific reports. DOI: 10.1038/s41598-018-26601-3
- Perrot et al., (2018) Fungal glutathione transferases as tools to explore the chemical diversity of Amazonian wood extractives. ACS sustainable chemistry and engineering. DOI: 10.1021/acssuschemeng.8b02636