Effective hydrolysis of lignocelluloses for producing reducing sugar is impeded by the covalent binding of hemicellulose and cellulose through lignin, which could be eliminated by laccases. This study identified a novel thermostable laccase from Bacillus safensis TCCC 111022 and created an iterative mutant E231D/Y441H, exhibiting 1.59-fold greater specific activity and a 183 % greater half-life at 80°C than the wild-type enzyme. Computational analysis revealed that the stability and activity of the E231D/Y441H could be simultaneously enhanced by increasing the flexibility of the ring around the substrate binding pocket. Additionally, the saccharification efficiency of sugarcane bagasse and corn stalks were both enhanced by 235 % in the system adding E231D/Y441H, mixed-cellulases, and mediator (1-hydroxybenzotriazole) compared to the samples treated with mixed-cellulases. The findings of this research provide a reference for the degradation of lignocellulosic substrates and contribute to the sustainable development of biomass-based industries.

中文翻译：

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同时增强安全芽孢杆菌衍生漆酶的活性和稳定性及其在木质纤维素糖化中的应用


木质素纤维素和纤维素通过木质素的共价结合阻碍了木质纤维素的有效水解以产生还原糖，而木质素可以被漆酶消除。本研究从安全芽孢杆菌 TCCC 111022 中鉴定出一种新型热稳定漆酶，并创造了一种迭代突变体 E231D/Y441H，在 80°C 下的比活性比野生型酶高 1.59 倍，半衰期长 183%。计算分析表明，通过增加底物结合袋周围环的柔韧性，可以同时增强 E231D/Y441H 的稳定性和活性。此外，与用混合纤维素酶处理的样品相比，在添加 E231D/Y441H、混合纤维素酶和介质（1-羟基苯并三唑）的系统中，甘蔗渣和玉米秸秆的糖化效率均提高了 235%。本研究结果为木质纤维素基材的降解提供了参考，为生物质产业的可持续发展做出了贡献。