Biogas Institute of Ministry of Agricultural and Rural Affairs, Section 4-13, Renmin South Road, Chengdu 610041, China.
Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agricultural and Rural Affairs, Section 4-13, Renmin South Road, Chengdu 610041, China.
Gigascience. 2021 Jan 27;10(1). doi: 10.1093/gigascience/giaa164.
Biogas production with anaerobic digestion (AD) is one of the most promising solutions for both renewable energy production and resolving the environmental problem caused by the worldwide increase in organic waste. However, the complex structure of the microbiome in AD is poorly understood.
In this study, we constructed a microbial gene catalog of AD (22,840,185 genes) based on 1,817 Gb metagenomic data derived from digestate samples of 56 full-scale biogas plants fed with diverse feedstocks. Among the gene catalog, 73.63% and 2.32% of genes were taxonomically annotated to Bacteria and Archaea, respectively, and 57.07% of genes were functionally annotated with KEGG orthologous groups. Our results confirmed the existence of core microbiome in AD and showed that the type of feedstock (cattle, chicken, and pig manure) has a great influence on carbohydrate hydrolysis and methanogenesis. In addition, 2,426 metagenome-assembled genomes were recovered from all digestate samples, and all genomes were estimated to be ≥80% complete with ≤10% contamination.
This study deepens our understanding of the microbial composition and function in the AD process and also provides a huge number of reference genome and gene resources for analysis of anaerobic microbiota.
利用厌氧消化（AD）生产沼气是可再生能源生产和解决全球有机废物增加所带来的环境问题的最有前途的解决方案之一。然而，AD 中微生物组的复杂结构仍未被充分了解。
在这项研究中，我们基于来自 56 个全规模沼气厂消化物样本的 1817 Gb 宏基因组数据，构建了 AD 的微生物基因目录（22840185 个基因）。在基因目录中，分别有 73.63%和 2.32%的基因被分类注释为细菌和古菌，57.07%的基因被功能注释为 KEGG 直系同源群。我们的结果证实了 AD 中存在核心微生物组，并且表明饲料类型（牛、鸡和猪粪）对碳水化合物水解和产甲烷有很大影响。此外，从所有消化物样本中回收了 2426 个宏基因组组装基因组，所有基因组估计完整度≥80%，污染度≤10%。
本研究加深了我们对 AD 过程中微生物组成和功能的理解，也为厌氧微生物群的分析提供了大量的参考基因组和基因资源。
