e-BioCenter, Department of Environmental Science and Policy, Università di Milano, Via Celoria 2, 20133 Milano, Italy.
e-BioCenter, Department of Food Environmental and Nutritional Science, Università di Milano, Via Mangiagalli 25, 20133 Milano, Italy.
Bioelectrochemistry. 2019 Feb;125:105-115. doi: 10.1016/j.bioelechem.2018.10.002. Epub 2018 Oct 16.
A new approach to microbial electrosynthesis is proposed, aimed at producing whole biomass from N and inorganic carbon, by electrostimulation of complex microbial communities. On a carbon-based conductor under constant polarization (-0.7 V vs SHE), an electroactive biofilm was enriched with autotrophic nitrogen fixing microorganims and led to biomass synthesis at higher amounts (up to 18 fold), as compared to controls kept at open circuit (OC). After 110 days, the electron transfer had increased by 30-fold, as compared to abiotic conditions. Metagenomics evidenced Nif genes associated with autotrophs (both Archaea and Bacteria) only in polarized biofilms, but not in OC. With this first proof of concept experiment, we propose to call this promising field 'bioelectrochemical nitrogen fixation' (e-BNF): a possible way to 'power' biological nitrogen fixation, organic carbon storage and soil fertility against desertification, and possibly a new tool to study the development of early prokaryotic life in extreme environments.
提出了一种新的微生物电合成方法，旨在通过电刺激复杂微生物群落，从 N 和无机碳中生产全生物质。在碳基导体上进行恒极化（相对于 SHE 为-0.7 V），富含自养固氮微生物的电活性生物膜导致生物质合成量增加（高达 18 倍），与保持开路（OC）的对照相比。经过 110 天，与非生物条件相比，电子转移增加了 30 倍。宏基因组学证明，只有在极化生物膜中而不是在 OC 中，与自养生物（古菌和细菌）相关的 Nif 基因。通过这个首次概念验证实验，我们建议将这个有前途的领域称为“生物电化学固氮”（e-BNF）：一种为生物固氮、有机碳储存和土壤肥力提供动力的可能方式，以防止沙漠化，并且可能是研究极端环境中早期原核生命发展的新工具。
