Resumen: Lignin biodegradation has been extensively studied in white-rot fungi, which largely belong to order Polyporales. Among the enzymes that wood-rotting polypores secrete, lignin peroxidases (LiPs) have been labeled as the most efficient. Here, we characterize a similar enzyme (ApeLiP) from a fungus of the order Agaricales (with ~13,000 described species), the soil-inhabiting mushroom Agrocybe pediades. X-ray crystallography revealed that ApeLiP is structurally related to Polyporales LiPs, with a conserved heme-pocket and a solvent-exposed tryptophan. Its biochemical characterization shows that ApeLiP can oxidize both phenolic and non-phenolic lignin model-compounds, as well as different dyes. Moreover, using stopped-flow rapid spectrophotometry and 2D-NMR, we demonstrate that ApeLiP can also act on real lignin. Characterization of a variant lacking the above tryptophan residue shows that this is the oxidation site for lignin and other high redox-potential substrates, and also plays a role in phenolic substrate oxidation. The reduction potentials of the catalytic-cycle intermediates were estimated by stopped-flow in equilibrium reactions, showing similar activation by H2O2, but a lower potential for the rate-limiting step (compound-II reduction) compared to other LiPs. Unexpectedly, ApeLiP was stable from acidic to basic pH, a relevant feature for application considering its different optima for oxidation of phenolic and nonphenolic compounds. Idioma: Inglés DOI: 10.3390/antiox10091446 Año: 2021 Publicado en: Antioxidants 10, 9 (2021), 1446 [23 pp] ISSN: 2076-3921 Factor impacto JCR: 7.675 (2021) Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 50 / 297 = 0.168 (2021) - Q1 - T1 Categ. JCR: FOOD SCIENCE & TECHNOLOGY rank: 12 / 144 = 0.083 (2021) - Q1 - T1 Categ. JCR: CHEMISTRY, MEDICINAL rank: 4 / 63 = 0.063 (2021) - Q1 - T1 Factor impacto CITESCORE: 6.5 - Biochemistry, Genetics and Molecular Biology (Q2)