Proteomic analysis reflects an environmental alkalinization-coupled pH-dependent mechanism of regulating lignocellulases in Trichoderma guizhouense NJAU4742
Proteomic analysis reflects an environmental alkalinization-coupled pH-dependent mechanism of regulating lignocellulases in Trichoderma guizhouense NJAU4742
复制标题
蛋白质组学分析反映了贵州木霉 NJAU4742 中调节木质纤维素酶的环境碱化耦合 pH 依赖性机制
DOI：
10.1186/s13068-020-1651-0
复制
发表时间：
2020-01-11
影响因子：
6.3
通讯作者：
Shen, Qirong
中科院分区：
文献类型：
--
作者：
Miao, Youzhi;Chen, Xing;Shen, Qirong
背景
丝状真菌具有高效分解植物生物质的能力，因此在生物燃料和生物加工工业中被广泛应用。据报道，在加工过程中，环境pH值会强烈影响所应用的功能性丝状真菌的性能。在本研究中，对贵州木霉NJAU4742在不同初始pH值下对稻草的发酵进行了详细研究。
结果
结果表明，NJAU4742菌株能够耐受3.0到9.0的环境pH值，但在酸性条件下具有明显更高的生长速度和胞外酶活性。在低环境pH值（<4）下，NJAU4742菌株通过环境碱化将环境pH值提升到最佳范围，实现了稻草的快速降解。进一步的蛋白质组学分析在固态发酵过程中总共鉴定出1139种胞内和胞外蛋白质，包括已定量的190种负责稻草降解的碳水化合物活性酶（CAZymes），例如19种纤维素酶、47种半纤维素酶和11种几丁质酶。同时，分析结果清楚地表明，分泌的木质纤维素酶根据环境pH值在分布上具有协同趋势，从而导致贵州木霉NJAU4742中木质纤维素酶的pH依赖性分类。
结论
研究发现，贵州木霉NJAU4742中大多数功能性木质纤维素酶受到环境pH值的不同调控，该菌株具有通过环境碱化提升环境pH值来加速生物质降解的能力。这些发现为生物燃料和生物加工工业中丝状真菌对植物生物质的生物降解提供了理论基础。
BackgroundFilamentous fungi have the ability to efficiently decompose plant biomass, and thus are widely used in the biofuel and bioprocess industries. In process, ambient pH has been reported to strongly affect the performance of the applied functional filamentous fungi. In this study,Trichoderma guizhouenseNJAU4742 was investigated under the fermentation of rice straw at different initial pH values for a detailed study.ResultsThe results showed that NJAU4742 strain could tolerate ambient pH values ranging from 3.0 to 9.0, but had significantly higher growth speed and extracellular enzyme activities under acidic conditions. At low ambient pH ( 4), NJAU4742 strain achieved rapid degradation of rice straw by elevating the ambient pH to an optimal range through environmental alkalinization. Further proteomic analysis identified a total of 1139 intracellular and extracellular proteins during the solid-state fermentation processes, including the quantified 190 carbohydrate-active enzymes (CAZymes) responsible for rice straw degradation, such as 19 cellulases, 47 hemicellulases and 11 chitinases. Meanwhile, the analysis results clearly showed that the secreted lignocellulases had a synergistic trend in distribution according to the ambient pH, and thus led to a pH-dependent classification of lignocellulases inT. guizhouenseNJAU4742.ConclusionsMost functional lignocellulases were found to be differently regulated by the ambient pH inT. guizhouenseNJAU4742, which had the ability of speeding up biomass degradation by elevating the ambient pH through environmental alkalinization. These findings contribute to the theoretical basis for the biodegradation of plant biomass by filamentous fungi in the biofuel and bioprocess industries.