厌氧消化污泥微生物组研究方法及应用

Anaerobic sludge digestion microbiome ― analytical methods and applications

摘要:

污泥厌氧消化是在消化污泥微生物组的协调下将剩余污泥中有机物转化为甲烷的微生物过程。与传统厌氧消化过程不同，污泥厌氧消化系统的进料底物为含有大量微生物细胞及胞外多聚物等复杂大分子有机物的剩余污泥。因此，厌氧消化污泥微生物组的种群组成、功能及种群间互作关系等异常复杂，使厌氧消化污泥微生物组分析成为难点问题。但近年来高通量测序技术及生物信息学分析方法的快速发展为消化污泥微生物组研究提供了契机，并迅速推动了该研究领域的发展。本文从4个方面梳理、总结厌氧消化污泥微生物组的研究及应用现状：剩余活性污泥结构、组成及其厌氧消化；基于16S rRNA基因序列测序的微生物组研究；基于宏基因组及宏转录组分析的微生物组研究；厌氧消化污泥微生物组研究案例分析。最后我们提出了厌氧消化污泥微生物组研究亟待解决的关键科学问题。

Abstract:

Anaerobic sludge digestion is a methanogenic process, in which sludge microbiome mediate degradation of macromolecules in waste sludge to generate biogas. In contrast to traditional anaerobic digestion, the influent sludge predominantly consist of microbial cells and their extracellular polymeric substances (EPS), which are persist and resistant to biodegradation. Also, it is a challenge to identify the sources of living microorganisms in anaerobic sludge digesters from influent waste sludge or indigenous digestion populations. Therefore, the population composition, function and their interactions of anaerobic sludge digestion microbiome have rarely been illustrated before. Nonetheless, the rapid development of high throughput sequencing techniques and bioinformatics analytical methods have enable the investigation of microbiomes of complex microbial systems, including the anaerobic sludge digesters. Here, we have comprehensively reviewed and discussed the recent development of anaerobic sludge digestion microbiome in four aspects, with a focus on waste activated sludge: (1) structure and composition of waste activated sludge, and anaerobic sludge digestion; (2) 16S rRNA gene-based analysis methods to study digestion sludge microbiome; (3) metagenome- and metatranscriptome-based analysis methods to study digestion sludge microbiome; (4) case study on digestion sludge microbiome. In addition, major challenges and further developments toward understanding the digestion sludge microbiome are identified and discussed.