Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China.
Civil Engineering, School of Engineering, College of Science and Engineering, National University of Ireland, Galway, Galway H91 TK33, Ireland.
Bioresour Technol. 2022 Sep;360:127535. doi: 10.1016/j.biortech.2022.127535. Epub 2022 Jun 29.
Anaerobic digestion is a prevalent bioenergy production process relying on a complex network of symbiotic interactions, where the nutrient based cross-feeding is an essential microbial mechanism. Here, the cross-feeding function was assessed by analyzing extracellular polymeric substances-associated amino acids in microbial aggregates collected from 14 lab-scale anaerobic digesters, as well as deciphering their genetically biosynthetic potential by syntrophic bacteria and methanogens. The total concentration of essential amino acids ranged from 1.2 mg/g VSS to 174.0 mg/g VSS. The percentages of glutamic acid (8.5 ∼ 37.6%), lysine (2.7 ∼ 22.6%), alanine (5.6 ∼ 13.2%), and valine (3.0 ∼ 10.4%) to the total amount of detected amino acids were the highest in most samples. Through metagenomics analysis, several investigated syntrophs (i.e., Smithella, Syntrophobacter, Syntrophomonas, and Mesotoga) and methanogens (i.e., Methanothrix and Methanosarcina) were auxotrophies, but the genetic ability of syntrophs and methanogens to synthesize some essential amino acids could be complementary, implying potential cross-feeding partnership.
厌氧消化是一种普遍的生物能源生产过程，依赖于共生相互作用的复杂网络，其中基于营养的交叉喂养是一种重要的微生物机制。在这里，通过分析从 14 个实验室规模的厌氧消化器中收集的微生物聚集体中的细胞外聚合物相关氨基酸，以及通过共生物和产甲烷菌破译其遗传生物合成潜力，评估了交叉喂养功能。必需氨基酸的总浓度范围为 1.2 mg/g VSS 至 174.0 mg/g VSS。在大多数样品中，谷氨酸（8.5∼37.6%）、赖氨酸（2.7∼22.6%）、丙氨酸（5.6∼13.2%）和缬氨酸（3.0∼10.4%）的百分比对检测到的氨基酸总量最高。通过宏基因组学分析，一些研究的共生物（即 Smithella、Syntrophobacter、Syntrophomonas 和 Mesotoga）和产甲烷菌（即 Methanothrix 和 Methanosarcina）是营养缺陷型，但共生物和产甲烷菌合成一些必需氨基酸的遗传能力可能是互补的，暗示存在潜在的交叉喂养关系。
