Roret Thomas, Thuillier Anne, Favier Frédérique, Gelhaye Eric, Didierjean Claude, Morel-Rouhier Mélanie
Université de Lorraine, UMR 7036 CRM(2), F-54506 Vandoeuvre-lès-Nancy, France; CNRS, UMR 7036 CRM(2), F-54506 Vandoeuvre-lès-Nancy, France.
Université de Lorraine, UMR 1136 Interactions Arbres/Microorganismes, F-54506 Vandoeuvre-lès-Nancy, France; INRA, UMR 1136 Interactions Arbres/Microorganismes, F-54280 Champenoux, France.
Fungal Genet Biol. 2015 Oct;83:103-112. doi: 10.1016/j.fgb.2015.09.002. Epub 2015 Sep 5.
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.
细胞内解毒系统对于木材降解真菌的生存至关重要。在这些系统中，谷胱甘肽转移酶可能发挥主要作用，因为该酶家族在木质素分解真菌中特别丰富。特别是Ure2p类占黄孢原毛平革菌（Phanerochaete chrysosporium）谷胱甘肽转移酶总数的三分之一。这些蛋白质在系统发育上已被分为两个亚类，称为Ure2pA和Ure2pB。由于与先前表征的细菌同工型具有共同的结构和功能特征，Ure2pB可归类为Nu谷胱甘肽转移酶。Ure2pA更可被视为类Nu谷胱甘肽转移酶，因为它们表现出许多差异。与Nu谷胱甘肽转移酶相比，Ure2pA具有经典的转移酶活性、更具差异的催化位点，并且其中一些具有更高的结构灵活性。对该Ure2pA亚类的四个成员（PcUre2pA4、PcUre2pA5、PcUre2pA6和PcUre2pA8）的表征揭示了特定的功能和结构特征，表明这些酶已经快速进化和分化，可能是为了适应与木材分解相关的复杂化学环境。
