基于木质素模型化合物的木质素生物降解过程中漆酶与底物结合亲和力及相互作用的机理研究

Efficient degradation of lignin is a key process during composting of municipal solid waste. Many microorganisms are able to degrade and utilize the components of lignin. The ability of microbes to degrade lignin is due to their degrading enzymes such as laccase. However, the interactive mechanisms involved in lignin and laccase are still unclear but important for contributing to the improvement of effectiveness of waste composting. The present project selected dehydrogenation polymer (DHP) that was directly used as lignin in many previous studies and oligomer lignin model compounds as representative of lgnin. The present project further employed fluorescence spectrum, nuclear magnetic resonnance and bioinformatics methods such as automatic molecular docking simulations and molecular dynamics simulations to systematacially analyze the interaction mechanisms between lignin and laccase. The detailed interactions were investigated, which revealed the key amino acid residues interacted with substrates by hydrogen bonds (H-bonds), van der Waals and/or hydrophobic interactions. The present study further analyzed the function of these key residues during composting of municipal solid waste. The present work could provide the theoretical and scientific foundation for the efficient degradation of lignin and efficient composting of municipal solid waste.

城市生活垃圾中木质素的高效降解是城市生活垃圾高效堆肥的关键。研究已经发现许多微生物对垃圾木质素具有很强的降解能力。微生物降解垃圾木质素主要依靠具有功能齐全的木质素降解酶系。这些酶系中漆酶由于具有高效催化氧化木质素的能力而最受关注。然而，漆酶降解木质素的机制，尤其是漆酶和木质素之间相互作用机理仍旧很不清晰，缺少深入研究，一定程度上阻碍了垃圾堆肥效益的提高。本项目拟在许多研究中被直接用作木质素的脱氢聚合物（DHP）及结构多样的低聚体木质素模型化合物来代表木质素，拟采用荧光光谱、核磁共振并结合分子对接、分子动力学模拟等生物信息学方法对木质素与漆酶的相互作用进行系统深入的研究。研究工作将阐明它们之间的氢键、范德华力、疏水性等作用情况，揭示发挥关键作用的氨基酸残基，分析这些相互作用在降解过程中的功能，可望为城市生活垃圾木质素的高效降解，及进一步地为城市生活垃圾高效堆肥，提供有关的理论基础和科学依据。

城市生活垃圾中木质素的高效降解是城市生活垃圾高效堆肥的关键。研究已经发现许多微生物对垃圾木质素具有很强的降解能力。微生物降解垃圾木质素主要依靠具有功能齐全的木质素降解酶系。这些酶系中漆酶由于具有高效催化氧化木质素的能力而最受关注。然而，漆酶降解木质素的机制，尤其是漆酶和木质素之间相互作用机理仍旧很不清晰，缺少深入研究，一定程度上阻碍了垃圾堆肥效益的提高。本项目在许多研究中被直接用作木质素的脱氢聚合物（DHP）及结构多样的低聚体木质素模型化合物来代表木质素，采用荧光光谱、核磁共振并结合分子对接、分子动力学模拟等生物信息学方法对木质素与漆酶的相互作用进行系统深入的研究。研究工作较深入阐明了它们之间的氢键、范德华力、疏水性等作用情况，揭示了发挥关键作用的氨基酸残基，分析了这些相互作用在降解过程中的功能，可望为城市生活垃圾木质素的高效降解，及进一步地为城市生活垃圾高效堆肥，提供有关的理论基础和科学依据。