【摘要】 以Shewanella sp. RQs-106为模式菌株，研究了细胞浓度、间硝基苯磺酸钠(3-NBS)浓度和氧化石墨烯(GO)对3-NBS生物还原速率及细胞分泌黄素类物质的影响，并揭示了胞外黄素在3-NBS厌氧生物还原中的作用.结果表明，以乳酸钠为电子供体，细胞分泌的黄素类物质会随着3-NBS浓度的增大而增加.黄素腺嘌呤二核苷酸转运蛋白基因(bfe)的缺失，使黄素分泌量减少22.8%,3-NBS的生物还原速率下降55.4%;添加20 mg/L GO的体系中，胞外黄素对3-NBS直接还原的贡献率为33.7%,参与GO介导下的3-NBS还原的贡献率为14.7%.上述研究表明，黄素参与了3-NBS的厌氧生物还原，并在胞外电子传递中起到了重要作用.更多还原

【Abstract】 Using Shewanella sp. RQs-106 as a model strain, the effects of cell concentration, sodium 3-nitrobenzene sulfonate(3-NBS) concentration and graphene oxide(GO) on the bio-reduction rate of 3-NBS and secreted flavins are investigated, and the role of extracellular flavins during the anaerobic bio-reduction of 3-NBS is revealed. The results show that the concentration of the secreted flavins increases with the increase of 3-NBS concentration using sodium lactate as an electron donor. The deletion of flavin adenine dinucleotide transporter gene(bfe) results in 22.8% and 55.4% of decreases in the amount of the secreted flavins and the bio-reduction rate of 3-NBS, respectively. In 20 mg/L GO-supplemented system, the contributions of extracellular flavins to direct and GO-mediated reduction of 3-NBS are 33.7% and 14.7%, respectively. The above results show that the secreted flavins participate in 3-NBS anaerobic bio-reduction and play an important role in extracellular electron transfer.更多还原