The performance of bioelectrochemical systems (BESs) is significantly influenced by metabolic interactions within a particular microbial community. Although some studies show that interspecific metabolic cooperation benefits BESs performance, the effect of interspecific substrate competition on BESs performance has not yet been discussed. Herein, the impact of interspecific competition is investigated by monitoring the extracellular electron transfer (EET) of exoelectrogenic Shewanella oneidensis MR-1 and non-exoelectrogenic Citrobacter freundii An1 alone and simultaneously. The bacterial consortia generate the highest current of 38.4 μA·cm^-2, 6 times of that produced by the single strain S. oneidensis MR-1. Though S. oneidensis MR-1 loses out to C. freundii An1 in solution, the competition enhances the metabolic activity of S. oneidensis MR-1 on electrode, which facilitates the biofilm formation and therefore helps S. oneidensis MR-1 to gain an competitive advantage over C. freundii An1. Increased metabolic activity triggers more electrons generation and flavin secretion of S. oneidensis MR-1 which contributes to its excellent exoelectrogenic capacity. The proteomics analysis confirms that the expression of proteins related to lactate metabolism, biofilm formation, and outer membrane c-type cytochromes are significantly upregulated in S. oneidensis MR-1 from bacterial consortia.

生物电化学系统 (BES) 的性能受特定微生物群落内代谢相互作用的显着影响。虽然一些研究表明种间代谢合作有利于 BESs 性能，但种间底物竞争对 BESs 性能的影响尚未讨论。在此，通过单独和同时监测外生希瓦氏菌MR-1 和非外生电生柠檬酸杆菌An1的细胞外电子转移 (EET) 来研究种间竞争的影响。细菌聚生体产生的最高电流为38.4 μA·cm ^-2，是单一菌株S. oneidensis MR-1产生的电流的6 倍。尽管S. oneidensis MR-1在溶液中输给了C. freundii An1，竞争增强了S. oneidensis MR-1在电极上的代谢活性，促进了生物膜的形成，从而帮助S. oneidensis MR-1获得了竞争优势优于C. freundii An1。代谢活动的增加会触发S. oneidensis MR-1产生更多的电子和黄素分泌，这有助于其出色的外生电能力。蛋白质组学分析证实，与乳酸代谢、生物膜形成和外膜c型细胞色素相关的蛋白质在S. oneidensis 中的表达显着上调 来自细菌聚生体的 MR-1。