Publications by authors named "Anne Thuillier"

5 Publications

  • Page 1 of 1

Evolutionary divergence of Ure2pA glutathione transferases in wood degrading fungi.

Fungal Genet Biol 2015 Oct 5;83:103-112. Epub 2015 Sep 5.

Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, F-54506 Vandoeuvre-lès-Nancy, France; INRA, UMR 1136 Interactions Arbres/Microorganismes, F-54280 Champenoux, France. Electronic address:

The intracellular systems of detoxification are crucial for the survival of wood degrading fungi. Within these systems, glutathione transferases could play a major role since this family of enzymes is specifically extended in lignolytic fungi. In particular the Ure2p class represents one third of the total GST number in Phanerochaete chrysosporium. These proteins have been phylogenetically split into two subclasses called Ure2pA and Ure2pB. Ure2pB can be classified as Nu GSTs because of shared structural and functional features with previously characterized bacterial isoforms. Ure2pA can rather be qualified as Nu-like GSTs since they exhibit a number of differences. Ure2pA possess a classical transferase activity, a more divergent catalytic site and a higher structural flexibility for some of them, compared to Nu GSTs. The characterization of four members of this Ure2pA subclass (PcUre2pA4, PcUre2pA5, PcUre2pA6 and PcUre2pA8) revealed specific functional and structural features, suggesting that these enzymes have rapidly evolved and differentiated, probably to adapt to the complex chemical environment associated with wood decomposition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fgb.2015.09.002DOI Listing
October 2015

Transcriptomic responses of Phanerochaete chrysosporium to oak acetonic extracts: focus on a new glutathione transferase.

Appl Environ Microbiol 2014 Oct 8;80(20):6316-27. Epub 2014 Aug 8.

Université de Lorraine, IAM, UMR 1136, IFR 110 EFABA, Champenoux, France INRA, IAM, UMR 1136, Vandoeuvre-les-Nancy, France

The first steps of wood degradation by fungi lead to the release of toxic compounds known as extractives. To better understand how lignolytic fungi cope with the toxicity of these molecules, a transcriptomic analysis of Phanerochaete chrysosporium genes was performed in the presence of oak acetonic extracts. It reveals that in complement to the extracellular machinery of degradation, intracellular antioxidant and detoxification systems contribute to the lignolytic capabilities of fungi, presumably by preventing cellular damages and maintaining fungal health. Focusing on these systems, a glutathione transferase (P. chrysosporium GTT2.1 [PcGTT2.1]) has been selected for functional characterization. This enzyme, not characterized so far in basidiomycetes, has been classified first as a GTT2 compared to the Saccharomyces cerevisiae isoform. However, a deeper analysis shows that the GTT2.1 isoform has evolved functionally to reduce lipid peroxidation by recognizing high-molecular-weight peroxides as substrates. Moreover, the GTT2.1 gene has been lost in some non-wood-decay fungi. This example suggests that the intracellular detoxification system evolved concomitantly with the extracellular ligninolytic machinery in relation to the capacity of fungi to degrade wood.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.02103-14DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4178660PMC
October 2014

Atypical features of a Ure2p glutathione transferase from Phanerochaete chrysosporium.

FEBS Lett 2013 Jul 24;587(14):2125-30. Epub 2013 May 24.

Université de Lorraine, IAM, UMR 1136, IFR 110 EFABA,Vandoeuvre-lès-Nancy F-54506, France.

Glutathione transferases (GSTs) are known to transfer glutathione onto small hydrophobic molecules in detoxification reactions. The GST Ure2pB1 from Phanerochaete chrysosporium exhibits atypical features, i.e. the presence of two glutathione binding sites and a high affinity towards oxidized glutathione. Moreover, PcUre2pB1 is able to efficiently deglutathionylate GS-phenacylacetophenone. Catalysis is not mediated by the cysteines of the protein but rather by the one of glutathione and an asparagine residue plays a key role in glutathione stabilization. Interestingly PcUre2pB1 interacts in vitro with a GST of the omega class. These properties are discussed in the physiological context of wood degrading fungi.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.febslet.2013.05.031DOI Listing
July 2013

Xenomic networks variability and adaptation traits in wood decaying fungi.

Microb Biotechnol 2013 May 2;6(3):248-63. Epub 2013 Jan 2.

Université de Lorraine, IAM, UMR 1136, IFR 110 EFABA, Vandoeuvre-lès-Nancy, F-54506, France.

Fungal degradation of wood is mainly restricted to basidiomycetes, these organisms having developed complex oxidative and hydrolytic enzymatic systems. Besides these systems, wood-decaying fungi possess intracellular networks allowing them to deal with the myriad of potential toxic compounds resulting at least in part from wood degradation but also more generally from recalcitrant organic matter degradation. The members of the detoxification pathways constitute the xenome. Generally, they belong to multigenic families such as the cytochrome P450 monooxygenases and the glutathione transferases. Taking advantage of the recent release of numerous genomes of basidiomycetes, we show here that these multigenic families are extended and functionally related in wood-decaying fungi. Furthermore, we postulate that these rapidly evolving multigenic families could reflect the adaptation of these fungi to the diversity of their substrate and provide keys to understand their ecology. This is of particular importance for white biotechnology, this xenome being a putative target for improving degradation properties of these fungi in biomass valorization purposes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1751-7915.12015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3815920PMC
May 2013

Functional diversification of fungal glutathione transferases from the ure2p class.

Int J Evol Biol 2011 22;2011:938308. Epub 2011 Nov 22.

Unité Mixte de Recherches INRA UHP 1136 Interaction Arbres Microorganismes, IFR 110 Ecosystèmes Forestiers, Agroressources, Bioprocédés et Alimentation, Faculté des Sciences et Technologies, Nancy Université BP 70239, 54506 Vandoeuvre-lès-Nancy Cedex, France.

The glutathione-S-transferase (GST) proteins represent an extended family involved in detoxification processes. They are divided into various classes with high diversity in various organisms. The Ure2p class is especially expanded in saprophytic fungi compared to other fungi. This class is subdivided into two subclasses named Ure2pA and Ure2pB, which have rapidly diversified among fungal phyla. We have focused our analysis on Basidiomycetes and used Phanerochaete chrysosporium as a model to correlate the sequence diversity with the functional diversity of these glutathione transferases. The results show that among the nine isoforms found in P. chrysosporium, two belonging to Ure2pA subclass are exclusively expressed at the transcriptional level in presence of polycyclic aromatic compounds. Moreover, we have highlighted differential catalytic activities and substrate specificities between Ure2pA and Ure2pB isoforms. This diversity of sequence and function suggests that fungal Ure2p sequences have evolved rapidly in response to environmental constraints.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4061/2011/938308DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3227518PMC
August 2012