漆酶催化木质素氧化聚合或降解是自然界碳循环的重要环节，其作用机制一直是生物质科学领域的研究热点。本文采用分子模拟技术进行研究，首先构建Myceliophthora thermophila（Mth）漆酶的3D模型，然后用9种木质素模型物在Mth漆酶T₁ Cu口袋区做分子对接。结果表明，Mth漆酶中4个Cu离子与高度保守的4个氨基酸片段结合，Mth漆酶与Melanocarpus albomyces漆酶亲缘关系最近（Identity >74%），以之为模板可得到高质量的3D模型，Ramachandran Plot分析证明模型中所有氨基酸构象都是合理的。在Mth漆酶T₁ Cu活性口袋区，木质素单体与Ala₁₉₂、Lys₁₈₈和Trp₅₀₇氢键结合，脂肪链端羧基化会影响Trp₅₀₇形成氢键，若酚羟基邻位被双甲氧基取代，则会降低单体的结合能。木质素模型物聚合度越高，结合能越低，二者线性相关。由于空间位阻效应，四聚体不能进入活性口袋，需要介体才能被Mth漆酶催化氧化。

Laccases catalyze the oxidative polymerization or degradation of lignin,which plays an important role in the global carbon cycle.Their catalytic mechanism has attracted much attention in the field of biomass science.In the investigation,a 3D model of Myceliophthora thermophila (Mth) laccase was constructed by means of the in-sili- co molecular simulation,and then the docking experiments of nine lignin model compounds were performed in the region of T₁ copper active pocket in the Mth laccase.The results show that (1) the four copper ions in the Mth lac- case are bound with four highly-conserved amino acid fragments; (2) the Mth laccase and the Melanocarpus albo- myces (Mal) laccase have the nearest phylogenetic relationship with an identity of over 74%,and by the Mal lac- case as template,a high-quality model of Mth laccase can be constructed; (3) the Ramachandran plot analysis proves that the confirmations of all amino acid residues are reasonable and correct; (4) within the T₁ copper active pocket in the Mth laccase,monolignol units are bound with Ala₁₉₂ ,Lys₁₈₈ and Trp₅₀₇ through hydrogen bonding; (5) the carboxylation of the monolignol side chain will influence the formation of the hydrogen bonds at Trp₅₀₇ ,and the substitution with dual methoxyl groups at the ortho-position of phenolics will reduce the binding energy of the monolignol units; (6) the higher the polymerization degree of the lignin model compounds,the lower the binding energy will be,which can be correlated linearly with each other; and (7) due to stereo-hindrance,lignol tetramers cannot enter the active pocket,requiring mediators for the oxidation by the Mth laccase.