整合组学技术分析嗜热微生物降解生物质的偏好性与酶系高效分泌机制

In the new era, it has gradually become the theme of green biotechnology development that efficiently converting agricultural waste resources to functional food ingredients, additional agent and bio-based chemicals with high attached value, while thermophilic microorganisms have been widely concerned due to the strong ability to secrete enzymes possessing a good thermal stability, long half-life and low production cost. In this study, the amount and type of carbohydrate active enzymes in the thermophilic microbial genome, the degradation potential and preference of specific biomass are investigated by integrated-omics. With functional proteomics technology, it is expected to analyze the environmental influence factor of efficient secreted enzymes, clarifying the composition and concentration changes of extracellular enzymes of thermophilic microorganisms, efficient induced factors of auxiliary enzyme components and their synergistic functional cofactors. Also, combining fluorophore-assisted carbohydrate electrophoresis with sugar metabonomics technology, the diversity of intermediate metabolites and the restriction factors of high-efficiency bioconversion can be determined. Furthermore, with the network biology technology, it is expected to explore the mechanism of efficient secretion of the microbial extracellular glycoside hydrolase under different carbon source culture conditions and the preference for biomass, which provide theoretical and technical basis for the optimization of fermentation technology in industry.

进入新世纪，农业废弃物等资源高效转化形成高附值的功能食品原料、食品添加剂及生物基化学品已成绿色生物技术发展的重要方向，而嗜热微生物分泌的酶系热稳定性好、生产应用成本低而被广泛关注。本课题拟用整合组学的方法调研重要嗜热微生物基因组中碳水化合物活性酶的种类与数量，分析其降解模式与降解潜能；利用功能蛋白组学技术分析相关酶系高效分泌的条件与环境影响因素，阐明嗜热微生物胞外酶系中核心酶组分的种类与浓度变化、辅助酶组分高效诱导因素以及其辅助因子等增效功能；利用荧光辅助糖电泳（FACE）结合糖质谱等糖代谢组技术分析检测中间代谢种类与数量，明确不同酶系降解形成寡糖的产物谱特征与其高效转化的限速瓶颈；基于网络生物学技术系统分析降解代谢动态网络，在系统生物学水平上认识相关嗜热微生物降解多糖的偏好性，了解其嗜热环境下酶系的高效分泌机制，为功能酶系定制形成绿色高效转化工艺奠定理论与技术基础。

进入新世纪，农业废弃物等资源高效转化形成高附值的功能食品原料、食品添加剂及生物基化学品已成绿色生物技术发展的重要方向，而嗜热微生物分泌的酶系热稳定性好、生产应用成本低被广泛关注。本课题首先构建整合组学技术，分析了高温堆肥生境中优势嗜热微生物梳棉状嗜热丝孢菌和褐色喜热裂孢菌降解木质纤维素的潜能，构建了嗜热真菌和嗜热放线菌高效降解微生物组合，并阐明了调控偏利共生及其酶协同分泌机制，明确了限制褐色喜热裂孢菌高效降解结晶纤维素的主要障碍，并对清除此障碍发挥主要功能的特异性木聚糖酶系进行了功能和结构的解析，并对相关酶组分进行了理性设计，这为人工构建高效降解木质纤维素的微生物组合与酶系提供了全新思路；重点利用整合组学方法系统地研究了嗜热毛壳菌对木质纤维素的生物质降解偏好性、生物质降解过程中的酶系诱导等表达的时序性和LPMO、GH酶类等不同降解酶组分的协同性，这为进一步丰富和完善结晶纤维素的降解理论体系奠定基础；利用整合功能组学方法分析了嗜热链霉菌 F-3 对生物质废弃物的降解偏好性，阐明嗜热微生物胞外酶系中几丁质核心酶组分的种类与浓度变化、胞外主要功能酶系的高效协同降解机制，有助于指导其工业应用方向；相关方法体系应于探索黑曲霉对多种粮食加工副产物中多糖组分的降解利用的偏好性、产物谱及影响因素，为粮食加工副产物的绿色高效转化工艺的形成奠定了理论与技术基础。