Lack of Periplasmic Non-heme Protein SorA Increases Shewanella decolorationis Current Generation
Lack of Periplasmic Non-heme Protein SorA Increases Shewanella decolorationis Current Generation
复制标题
周质非血红素蛋白 SorA 的缺乏会增加当前一代希瓦氏菌的脱色。
DOI：
10.3389/fmicb.2020.00262
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发表时间：
2020-02-25
影响因子：
5.2
通讯作者：
Xu, Meiying
中科院分区：
文献类型：
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作者：
Kong, Guannan;Song, Da;Xu, Meiying
细菌细胞外电子传递（EET）在许多自然过程和工程过程中起着重要的作用。在EET过程中，一些周质非血红素氧化还原蛋白通常与C型细胞色素（CTC）共存。然而，与CTC相反，对这些非血红素氧化还原蛋白在EET中的作用知之甚少。本研究对脱色希瓦氏菌S12的转录组进行了研究，结果表明，与偶氮染料还原过程相比，在微生物燃料电池（MFC）中，电极呼吸过程中编码周质亚硫酸盐脱氢酶结合亚基索拉A的基因表达显著上调。缺失索拉A的突变株催化MFC的最大电流密度（Δ索拉A）比野生株S12提高了25%（20 vs. 16 μA/cm 2）。破坏索拉A后，生物膜的形成和阳极生物膜电流的产生均增加，这表明索拉A在S.脱色S12抑制电极呼吸。相反，破坏索拉对呼吸没有影响。脱色是以氧、富马酸盐、偶氮染料或柠檬酸铁为电子受体的S12。这是第一次报告的特定影响的周质非血红素氧化还原蛋白EET电极，并提供了新的信息，为提高细菌电流的产生。
Bacterial extracellular electron transport (EET) plays an important role in many natural and engineering processes. Some periplasmic non-heme redox proteins usually coexist with c-type cytochromes (CTCs) during the EET process. However, in contrast to CTCs, little is known about the roles of these non-heme redox proteins in EET. In this study, the transcriptome of Shewanella decolorationis S12 showed that the gene encoding a periplasmic sulfite dehydrogenase molybdenum-binding subunit SorA was significantly up-regulated during electrode respiration in microbial fuel cells (MFCs) compared with that during azo-dye reduction. The maximum current density of MFCs catalyzed by a mutant strain lacking SorA (ΔsorA) was 25% higher than that of wild strain S12 (20 vs. 16 μA/cm2). Both biofilm formation and the current generation of the anodic biofilms were increased by the disruption of sorA, which suggests that the existence of SorA in S. decolorationis S12 inhibits electrode respiration. In contrast, disruption of sorA had no effect on respiration by S. decolorationis S12 with oxygen, fumarate, azo dye, or ferric citrate as electron acceptors. This is the first report of the specific effect of a periplasmic non-heme redox protein on EET to electrode and provides novel information for enhancing bacterial current generation.