LPMO (lytic polysaccharide monooxygenase) represents a unique paradigm of cellulosic biomass degradation by an oxidative mechanism. Understanding the role of LPMO in deconstructing crystalline cellulose is fundamental to the enzyme's biological function and will help to specify the use of LPMO in biorefinery applications. Here we show with real-time atomic force microscopy that C1 and C4 oxidizing types of LPMO from Neurospora crassa (NcLPMO9F, NcLPMO9C) bind to nanocrystalline cellulose with high preference for the very same substrate surfaces that are also used by a processive cellulase (Trichoderma reesei CBH I) to move along during hydrolytic cellulose degradation. The bound LPMOs, however, are immobile during their adsorbed residence time ( ~ 1.0 min for NcLPMO9F) on cellulose. Treatment with LPMO resulted in fibrillation of crystalline cellulose and strongly ( ≥ 2-fold) enhanced the cellulase adsorption. It also increased enzyme turnover on the cellulose surface, thus boosting the hydrolytic conversion.Understanding the role of enzymes in biomass depolymerization is essential for the development of more efficient biorefineries. Here, the authors show by atomic force microscopy the real-time mechanism of cellulose deconstruction by lytic polysaccharide monooxygenases.

中文翻译：

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纤维素氧化酶解构的单分子研究。

LPMO（裂解多糖单加氧酶）代表了通过氧化机制降解纤维素生物质的独特范例。了解LPMO在解构结晶纤维素中的作用是酶的生物学功能的基础，并且将有助于指定LPMO在生物精炼应用中的用途。在这里，我们通过实时原子力显微镜显示了来自神经孢霉的C1和C4氧化类型的LPMO（NcLPMO9F，NcLPMO9C）与纳米晶纤维素结合，对同样的底物表面高度偏爱，而底物表面也被过程性纤维素酶（Trichoderma reesei）使用。 CBH I）在水解纤维素降解过程中会移动。但是，结合的LPMO在纤维素上的吸附停留时间（对于NcLPMO9F约为1.0分钟）是不动的。LPMO处理导致结晶纤维素原纤化，并强烈（≥2倍）增强了纤维素酶的吸附。它还增加了纤维素表面的酶转化率，从而促进了水解转化。了解酶在生物质解聚中的作用对于开发更高效的生物精炼厂至关重要。在这里，作者通过原子力显微镜显示了溶解性多糖单加氧酶对纤维素解构的实时机制。