Combining anaerobic digestion (AD) and microbial electrochemical technologies (MET) in AD-MET holds great potential. Methanogens have been identified as one cause of decreased electrochemical activity and deterioration of Geobacter spp. biofilm anodes. A better understanding of the different interactions between methanogenic genera/species and Geobacter spp. biofilms is needed to shed light on the observed reduction in electrochemical activity and stability of Geobacter spp. dominated biofilms as well as observed changes in microbial communities of AD-MET. Here, we have analyzed electrochemical parameters and changes in the microbial community of Geobacter spp. biofilm anodes when exposed to three representative methanogens with different metabolic pathways, i.e., Methanosarcina barkeri, Methanobacterium formicicum, and Methanothrix soehngenii. M. barkeri negatively affected the performance and stability of Geobacter spp. biofilm anodes only in the initial batches. In contrast, M. formicicum did not affect the stability of Geobacter spp. biofilm anodes but caused a decrease in maximum current density of ~37%. M. soehngenii induced a coloration change of Geobacter spp. biofilm anodes and a decrease in the total transferred charge by ~40%. Characterization of biofilm samples after each experiment by 16S rRNA metabarcoding, whole metagenome nanopore sequencing, and shotgun sequencing showed a higher relative abundance of Geobacter spp. after exposure to M. barkeri as opposed to M. formicicum or M. soehngenii, despite the massive biofilm dispersal observed during initial exposure to M. barkeri.

将厌氧消化（AD）和微生物电化学技术（MET）相结合的 AD-MET 具有巨大的潜力。产甲烷菌已被确定为导致地杆菌属电化学活性降低和恶化的原因之一。生物膜阳极。更好地了解产甲烷属/种与地杆菌属之间的不同相互作用。需要生物膜来阐明观察到的地杆菌属电化学活性和稳定性的降低。主要生物膜以及观察到的 AD-MET 微生物群落的变化。在这里，我们分析了地杆菌属微生物群落的电化学参数和变化。当暴露于三种具有不同代谢途径的代表性产甲烷菌（即巴克甲烷八叠球菌、甲酸甲烷杆菌和苏氏甲烷丝菌）时，生物膜阳极。M. barkeri对地杆菌属的性能和稳定性产生负面影响。仅在最初批次中使用生物膜阳极。相比之下，M. formicum不影响地杆菌属的稳定性。生物膜阳极，但导致最大电流密度下降约 37%。M. soehngenii诱导地杆菌属的颜色变化。生物膜阳极和总转移电荷减少约 40%。每次实验后通过 16S rRNA 元条形码、全宏基因组纳米孔测序和鸟枪法测序对生物膜样品进行表征，结果显示地杆菌属的相对丰度较高。与M. formicum或M. soehngenii相比，暴露于M. barkeri后，尽管在初次接触M. barkeri期间观察到大量生物膜扩散。