000128056 001__ 128056
000128056 005__ 20241125101132.0
000128056 0247_ $$2doi$$a10.1128/aem.01844-22
000128056 0248_ $$2sideral$$a133886
000128056 037__ $$aART-2023-133886
000128056 041__ $$aeng
000128056 100__ $$0(orcid)0000-0003-4076-6118$$aFerreira, Patricia$$uUniversidad de Zaragoza
000128056 245__ $$aExpanding the Physiological Role of Aryl-Alcohol Flavooxidases as Quinone Reductases
000128056 260__ $$c2023
000128056 5060_ $$aAccess copy available to the general public$$fUnrestricted
000128056 5203_ $$aAryl-alcohol oxidases (AAOs) are members of the glucose-methanol-choline oxidase/dehydrogenase (GMC) superfamily. These extracellular flavoproteins have been described as auxiliary enzymes in the degradation of lignin by several white-rot basidiomycetes. In this context, they oxidize fungal secondary metabolites and lignin-derived compounds using O2 as an electron acceptor, and supply H2O2 to ligninolytic peroxidases. Their substrate specificity, including mechanistic aspects of the oxidation reaction, has been characterized in Pleurotus eryngii AAO, taken as a model enzyme of this GMC superfamily. AAOs show broad reducing-substrate specificity in agreement with their role in lignin degradation, being able to oxidize both nonphenolic and phenolic aryl alcohols (and hydrated aldehydes). In the present work, the AAOs from Pleurotus ostreatus and Bjerkandera adusta were heterologously expressed in Escherichia coli, and their physicochemical properties and oxidizing abilities were compared with those of the well-known recombinant AAO from P. eryngii. In addition, electron acceptors different from O2, such as p-benzoquinone and the artificial redox dye 2,6-Dichlorophenolindophenol, were also studied. Differences in reducing-substrate specificity were found between the AAO enzymes from B. adusta and the two Pleurotus species. Moreover, the three AAOs oxidized aryl alcohols concomitantly with the reduction of p-benzoquinone, with similar or even higher efficiencies than when using their preferred oxidizing-substrate, O2.
IMPORTANCE In this work, quinone reductase activity is analyzed in three AAO flavooxidases, whose preferred oxidizing-substrate is O2. The results presented, including reactions in the presence of both oxidizing substrates—benzoquinone and molecular oxygen—suggest that such aryl-alcohol dehydrogenase activity, although less important than its oxidase activity in terms of maximal turnover, may have a physiological role during fungal decay of lignocellulose by the reduction of quinones (and phenoxy radicals) from lignin degradation, preventing repolymerization. Moreover, the resulting hydroquinones would participate in redox-cycling reactions for the production of hydroxyl free radical involved in the oxidative attack of the plant cell-wall. Hydroquinones can also act as mediators for laccases and peroxidases in lignin degradation in the form of semiquinone radicals, as well as activators of lytic polysaccharide monooxygenases in the attack of crystalline cellulose. Moreover, reduction of these, and other phenoxy radicals produced by laccases and peroxidases, promotes lignin degradation by limiting repolymerization reactions. These findings expand the role of AAO in lignin biodegradation.
000128056 536__ $$9info:eu-repo/grantAgreement/ES/AEI/BIO2017-86559-R$$9info:eu-repo/grantAgreement/ES/CSIC/PIE-202120E019$$9info:eu-repo/grantAgreement/EC/H2020/720297/EU/New enzymatic oxidation/oxyfunctionalization technologies for added value bio-based products/EnzOx2$$9This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 720297-EnzOx2$$9info:eu-repo/grantAgreement/ES/MICINN-AEI/PID2019-103901GB-I00$$9info:eu-repo/grantAgreement/ES/MICINN/PID2021-126384OB-I00
000128056 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttp://creativecommons.org/licenses/by/3.0/es/
000128056 590__ $$a3.9$$b2023
000128056 592__ $$a1.016$$b2023
000128056 591__ $$aMICROBIOLOGY$$b57 / 161 = 0.354$$c2023$$dQ2$$eT2
000128056 593__ $$aApplied Microbiology and Biotechnology$$c2023$$dQ1
000128056 591__ $$aBIOTECHNOLOGY & APPLIED MICROBIOLOGY$$b51 / 174 = 0.293$$c2023$$dQ2$$eT1
000128056 593__ $$aFood Science$$c2023$$dQ1
000128056 593__ $$aEcology$$c2023$$dQ1
000128056 593__ $$aBiotechnology$$c2023$$dQ1
000128056 594__ $$a7.7$$b2023
000128056 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000128056 700__ $$aCarro, Juan
000128056 700__ $$aBalcells, Beatriz
000128056 700__ $$aMartínez, Angel T.
000128056 700__ $$aSerrano, Ana
000128056 7102_ $$11002$$2060$$aUniversidad de Zaragoza$$bDpto. Bioq.Biolog.Mol. Celular$$cÁrea Bioquímica y Biolog.Mole.
000128056 773__ $$g89, 5 (2023), [14 pp.]$$tApplied and Environmental Microbiology$$x0099-2240
000128056 8564_ $$s1590408$$uhttps://zaguan.unizar.es/record/128056/files/texto_completo.pdf$$yVersión publicada
000128056 8564_ $$s2461609$$uhttps://zaguan.unizar.es/record/128056/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000128056 909CO $$ooai:zaguan.unizar.es:128056$$particulos$$pdriver
000128056 951__ $$a2024-11-22-11:59:26
000128056 980__ $$aARTICLE