Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR, USA.
J Appl Microbiol. 2011 Nov;111(5):1108-15. doi: 10.1111/j.1365-2672.2011.05129.x. Epub 2011 Sep 13.
Isolation, identification and characterization of a new exoelectrogenic bacterium from a microbial fuel cell (MFC).
Exoelectrogenic bacterial strain SX-1 was isolated from a mediator-less MFC by conventional plating techniques with ferric citrate as electron acceptor under anaerobic condition. Phylogenetic analysis of the 16S rDNA sequence revealed that it was related to the members of Citrobacter genus with Citrobacter sp. sdy-48 being the most closely related species. The bacterial strain SX-1 produced electricity from citrate, acetate, glucose, sucrose, glycerol and lactose in MFCs with the highest current density of 205 mA m(-2) generated from citrate. Cyclic voltammetry analysis indicated that membrane-associated proteins may play an important role in facilitating the electrons transferring from bacteria to electrode.
This is the first study that demonstrates that Citrobacter species can transfer electrons to extracellular electron acceptors. Citrobacter strain SX-1 is capable of generating electricity from a wide range of substrates in MFCs.
This finding increases the known diversity of power generating exoelectrogens and provided a new strain to explore the mechanisms of extracellular electron transfer from bacteria to electrode. The wide range of substrate utilization by SX-1 increases the application potential of MFCs in renewable energy generation and waste treatment.
从微生物燃料电池（MFC）中分离、鉴定和表征一种新型的外生菌。
通过常规的平板划线技术，在厌氧条件下以柠檬酸铁作为电子受体，从无介体 MFC 中分离出外生菌 SX-1。16S rDNA 序列的系统发育分析表明，它与柠檬酸杆菌属的成员有关，与柠檬酸杆菌 sdy-48 最为密切相关。细菌菌株 SX-1 在 MFC 中从柠檬酸盐、乙酸盐、葡萄糖、蔗糖、甘油和乳糖中产生电流，从柠檬酸盐中产生的最高电流密度为 205 mA m(-2)。循环伏安分析表明，膜相关蛋白可能在促进电子从细菌向电极传递方面发挥重要作用。
这是首次证明柠檬酸杆菌属能够将电子转移到细胞外电子受体的研究。Citrobacter 菌株 SX-1 能够在 MFC 中从多种基质中发电。
这一发现增加了已知的发电外生菌的多样性，并提供了一种新的菌株来探索细菌到电极的细胞外电子转移机制。SX-1 的广泛基质利用增加了 MFC 在可再生能源发电和废物处理中的应用潜力。
