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Total records: 126
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[ 2013 ] Miki Y, Pogni R, Acebes S, Lucas F, Fernandez-Fueyo E, Baratto MC, Fernández MI, de los Ríos V, Ruiz-Dueñas FJ, Sinicropi A, Basosi R, Hammel KE, Guallar V, Martínez AT Formation of a tyrosine adduct involved in lignin degradation by Trametopsis cervina lignin peroxidase: A novel peroxidase activation mechanism Biochem. J., 452: 575-584

[ 2013 ] Peter S, Karich A, Ullrich R, Gröbe G, Scheibner K, Hofrichter M Enzymatic one-pot conversion of cyclohexane into cyclohexanone: Comparison of four fungal peroxygenases J. Mol. Cat. B, doi: 10.1016/j.molcatb.2013.09.016

[ 2013 ] Peter S, Kinne M, Ullrich R, Kayser G, Hofrichter M Epoxidation of linear, branched and cyclic alkenes catalyzed by unspecific peroxygenase Enz. Microb. Technol., 52: 370-376

[ 2013 ] Pezzella C, Lettera V, Piscitelli A, Giardina P, Sannia G Transcriptional analysis of Pleurotus ostreatus laccase genes Appl. Microbiol. Biotechnol., 97: 705-717

[ 2013 ] Piontek K, Strittmatter E, Ullrich R, Gröbe G, Pecyna MJ, Kluge M, Scheibner K, Hofrichter M, Plattner D Structural Basis of Substrate Conversion in a New Aromatic Peroxygenase: P450 Functionality with Benefits J. Biol. Chem., 288: 34767-34776

[ 2013 ] Ruiz-Dueñas FJ, Lundell T, Floudas D, Nagy LG, Barrasa JM, Hibbett DS, Martínez AT Lignin-degrading peroxidases in Polyporales: an evolutionary survey based on 10 sequenced genomes Mycologia, 105: 1428-1444

Lignin peroxidase (LiP) from Trametopsis cervina has an exposed catalytic tyrosine (Tyr-181)instead of the conserved tryptophan of other lignin-degrading peroxidases. Pristine LiP showed alag period in veratryl alcohol (VA) oxidation. However, LiP after turnover with H2O2/VA (VA-LiP)lacked this lag, and H2O2-pretreated LiP (H2O2-LiP) was inactive. MS analyses revealed that VALiPincludes one VA molecule covalently bound to the side-chain of Tyr-181, whereas H2O2-LiPcontains hydroxylated Tyr-181. No adduct is formed by the Y171N variant. Molecular dockingshowed that VA binding is favored by sandwich π stacking with Tyr-181 and Phe-89. EPRspectroscopy after peroxide activation of the pretreated LiPs showed other protein radicals than thetyrosine radical found in pristine LiP, which were assigned to a tyrosine/VA adduct radical in VALiPand a dihydroxyphenyalanine radical in H2O2-LiP. Both radicals are able to oxidize large lowredox-potential substrates, but H2O2-LiP is unable to oxidize high redox-potential substrates.Transient-state kinetics showed that the tyrosine/VA adduct strongly promotes (>100-fold)substrate oxidation by compound II, the rate-limiting step in catalysis. The novel activationmechanism is involved in ligninolysis, as demonstrated using lignin model substrates. This is thefirst report on autocatalytic modification, resulting in functional alteration, among class-IIperoxidases.