木质纤维素的微生物降解

Microbial degradation of lignocellulose

摘要:

木质纤维素广泛存在于自然界中，因结构复杂，其高效降解需要多种微生物的协同互作，由于参与木质纤维素降解的微生物种类繁多，其协同降解机理尚不完全明确。随着微生物分子生物学和组学技术的快速发展，将为微生物协同降解木质纤维素机制的研究提供新的方法和思路。笔者前期研究发现，细菌复合菌系在50 ℃下表现出强大的木质纤维素降解能力，菌系由可分离培养和暂时不可分离培养细菌组成，但是可分离培养细菌没有降解能力。通过宏基因组和宏转录组研究表明，与木质纤维素降解相关的某些基因表达量发生显著变化，通过组学方法有可能更加深入解释微生物协同降解木质纤维素的微生物学和酶学机理。文中从酶、纯培养菌株和复合菌群三个方面综述了木质纤维素微生物降解研究进展，着重介绍了组学技术在解析复合菌群作用机理方面的现状和应用前景，以期为探索微生物群落协同降解木质纤维素的机理提供借鉴。

Abstract:

Lignocellulose is widely found in the nature. The highly efficient degradation of lignocellulose requires synergistic interactions of varieties of microorganisms. The mechanism of synergistic interaction relationship is not entirely clear because it needs multitudinous microorganisms to participate in the process of lignocellulose degradation. With the development of microbial molecular biology and omics technology, some new methods will be provided for the research on the mechanism of microbial synergistic degradation of lignocellulose. Our previous research found that the bacterial composite microbial system shows strong degradation ability of lignocellulose at 50 °C. The consortium is composed of cultured and uncultured bacteria, but the former has no degradation ability. Metagenomics and metatranscriptomics show that the expression levels of some genes related to lignocellulosic degradation change significantly. It is possible to explain the microbiological and enzymatic mechanisms of lignocellulosic degradation by microorganisms through omics in the future. The research progress of lignocellulose microbial degradation is reviewed from the aspects of enzyme, pure culture strain, and microbial consortium. The current situation and application prospect of omics technology in analyzing the function mechanism of microbial consortium are also introduced, to provide reference for exploring synergistic interactions of lignocellulose microbial degradation.