Chongqing Key Laboratory of Bio-resource for Bioenergy, College of Resources and Environment, Southwest University, Chongqing 400715, China.
College of Resources and Environment, Southwest University, Chongqing, 400715, China.
Bioresour Technol. 2021 Oct;337:125377. doi: 10.1016/j.biortech.2021.125377. Epub 2021 Jun 3.
In this study, single-chamber and dual-chamber Microbial electrosynthesis (MES) with carbon fiber brushes as electrodes were operated at 15°C to compare and analyze the difference in methanogenic performance. Metatranscriptomic analysis showed that the relative abundance of electroactive microorganisms Syntrophomonas, Pseudomonas and Bacteroides in each group exceeded 90%, while the abundance of Geobacter was less than 4%. Acetoclastic methanogens Methahnosarcina was more enriched in dual-chamber MES (61.74%70.42%), and Methanothrix showed higher abundance in single-chamber MES (33.44%51.71%). Methahnosarcina and Methanothrix could interact with electroactive microorganisms to improve the electron transfer efficiency through direct interspecies electron transfer (DIET). Analysis of the methane metabolic pathways of low-temperature MES found acetoclastic pathway was domination, and single-chamber MES achieved acetate to acetyl-CoA through acetate-CoA ligase (EC: 6.2.1.1), whereas dual-chamber MES was by acetate kinase (EC: 2.7.2.1) and phosphate acetyltransferase (EC: 2.3.1.8). These results are beneficial to further research on the treatment of low-temperature wastewater.
在这项研究中，采用碳纤维刷作为电极的单室和双室微生物电解合成（MES）在 15°C 下运行，以比较和分析产甲烷性能的差异。宏转录组分析表明，每组中电活性微生物互营单胞菌、假单胞菌和拟杆菌的相对丰度均超过 90%，而地杆菌的丰度则低于 4%。在双室 MES 中，乙酸营养型产甲烷菌产甲烷八叠球菌（Methahnosarcina）更为丰富（61.74%70.42%），而单室 MES 中产甲烷丝状菌（Methanothrix）的丰度更高（33.44%51.71%）。产甲烷八叠球菌和产甲烷丝状菌可以通过直接种间电子传递（DIET）与电活性微生物相互作用，提高电子传递效率。对低温 MES 甲烷代谢途径的分析发现，乙酸营养型途径占主导地位，单室 MES 通过乙酰辅酶 A 合成酶（EC：6.2.1.1）将乙酸转化为乙酰辅酶 A，而双室 MES 则通过乙酸激酶（EC：2.7.2.1）和磷酸乙酰转移酶（EC：2.3.1.8）。这些结果有助于进一步研究低温废水的处理。
