Lytic polysaccharide monooxygenases promote oxidative cleavage of lignin and lignin-carbohydrate complexes during fungal degradation of lignocellulose
Lytic polysaccharide monooxygenases promote oxidative cleavage of lignin and lignin-carbohydrate complexes during fungal degradation of lignocellulose
复制标题
在木质纤维素的真菌降解过程中，裂解多糖单加氧酶促进木质素和木质素-碳水化合物复合物的氧化裂解
DOI：
10.1111/1462-2920.15648
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发表时间：
2021-06-24
影响因子：
5.1
通讯作者：
Yu, Hongbo
中科院分区：
文献类型：
--
作者：
Li, Fe;Zhang, Jialong;Yu, Hongbo
克服木质纤维素生物质的抗性，特别是木质素-碳水化合物复合物（LCCs）和木质素的交联断裂，对于碳循环和工业生物炼制都是必不可少的。多糖单加氧酶（Lytic多糖monooxygenase， LPMOs）是一种含铜酶，在真菌多糖的氧化降解过程中起关键作用。然而，综合分析表明，来自白腐菌平菇（Pleurotus ostreatus）的LPMOs与Fenton反应具有良好的相关性，并参与了本研究中难降解非多糖组分的降解。因此，LPMOs通过增强醌氧化还原循环中的铁还原参与细胞外Fenton反应。由LPMOs、对苯二酚和铁组成的Fenton反应体系可以有效地产生羟基自由基，然后切割lcc或木质素键。这一发现表明，在消除生物质抗性方面，LPMOs是被低估的辅助酶。
Overcoming lignocellulosic biomass recalcitrance, especially the cleavage of cross-linkages in lignin-carbohydrate complexes (LCCs) and lignin, is essential for both the carbon cycle and industrial biorefinery. Lytic polysaccharide monooxygenases (LPMOs) are copper-containing enzymes that play a key role in fungal polysaccharide oxidative degradation. Nevertheless, comprehensive analysis showed that LPMOs from a white-rot fungus, Pleurotus ostreatus, correlated well with the Fenton reaction and were involved in the degradation of recalcitrant nonpolysaccharide fractions in this research. Thus, LPMOs participated in the extracellular Fenton reaction by enhancing iron reduction in quinone redox cycling. A Fenton reaction system consisting of LPMOs, hydroquinone, and ferric iron can efficiently produce hydroxy radicals and then cleave LCCs or lignin linkages. This finding indicates that LPMOs are underestimated auxiliary enzymes in eliminating biomass recalcitrance.