Cagide Célica, Vallés Diego, Castro-Sowinski Susana
Sección Bioquímica, Instituto de Biología, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay.
Laboratorio de Biocatalizadores y sus Aplicaciones, Instituto de Química Biológica, Facultad de Ciencias, Universidad de La República, Igua 4225, Montevideo 11400, Uruguay.
Braz J Microbiol. 2025 Mar;56(1):67-78. doi: 10.1007/s42770-024-01595-5. Epub 2024 Dec 24.
Pseudomonas sp. AU10 is an Antarctic psychrotolerant bacterium that produces a dye-decolorizing peroxidase (DyP-AU10). The recombinant enzyme (rDyP-AU10) is a heme-peroxidase that decolors dyes and modifies kraft lignin. In this work, we report the best activity parameters for lignin modification (at 45 °C and pH 4) and show that the enzyme increases the number of aldehydes, ketones, and phenolic compounds. The analyses of the HPLC profile of samples also support that rDyP-AU10 induces the chemical change of kraft lignin. The enzyme also acts as a biobleaching agent on cellulose pulps, as shown by the reduction in kappa number. We also included experiments with a commercial laccase from Trametes versicolor and performed experiments using single enzymes and, in combination. The results show that rDyP-AU10 and the commercial laccase do not have a synergic activity as a modifying system, on cellulose pulp as substrates. However, results suggest that rDyP-AU10 holds potential as a member of the portfolio of lignin-modifying enzymes.
假单胞菌属AU10是一种南极耐冷细菌，可产生一种染料脱色过氧化物酶（DyP-AU10）。重组酶（rDyP-AU10）是一种血红素过氧化物酶，可使染料脱色并修饰硫酸盐木质素。在这项工作中，我们报告了木质素修饰的最佳活性参数（45°C和pH 4），并表明该酶增加了醛、酮和酚类化合物的数量。对样品的HPLC图谱分析也支持rDyP-AU10诱导了硫酸盐木质素的化学变化。如卡伯值降低所示，该酶还可作为纤维素纸浆的生物漂白剂。我们还进行了来自云芝的商业漆酶的实验，并分别使用单一酶及其组合进行了实验。结果表明，作为修饰系统，rDyP-AU10和商业漆酶在以纤维素纸浆为底物时没有协同活性。然而，结果表明rDyP-AU10作为木质素修饰酶组合的一员具有潜力。
