Abstract:
This study investigated electrochemical characteristics of Gram-positive, Nocardiopsis dassonvillei B17 facultative bacterium in bioelectrochemical systems. The results demonstrated that anodic and cathodic reaction rates were catalyzed by this bacterium, especially by utilization of aluminium alloy as a substrate. Cyclic voltammogram results depicted an increase of peak current and surface area through biofilm development, confirming its importance on catalysis of redox reactions. Phenazine derivatives were detected and their electron mediating behavior was evaluated exogenously. A symmetrical redox peak in the range of -59 to -159 mV/SHE was observed in cyclic voltammogram of bacterial solution supplemented with 12 μM phenazine, a result consistent with cyclic voltammogram of a 5-d biofilm, confirming its importance as an electron mediator in extracellular electron transfer. Furthermore, the dependency of bacterial catalysis and polarization potential were studied. These results suggested that B17 biofilm behaved as a biocathode and transferred electrons to bacterial cells through a mechanism associated with electron mediators.
摘要:
这项研究调查了革兰氏阳性,生物电化学系统中的诺卡氏菌B17兼性细菌。结果表明,该细菌催化了阳极和阴极反应速率,特别是利用铝合金作为基材。循环伏安图结果描绘了通过生物膜发展的峰值电流和表面积的增加,证实了其对氧化还原反应催化的重要性。检测了吩嗪衍生物,并对其电子介导行为进行了外源评估。在补充了12μM吩嗪的细菌溶液的循环伏安图中观察到-59至-159mV/SHE范围内的对称氧化还原峰,结果与5-d生物膜的循环伏安图一致,证实其作为细胞外电子转移中电子介体的重要性。此外,研究了细菌催化和极化电位的依赖性。这些结果表明,B17生物膜表现为生物阴极,并通过与电子介体相关的机制将电子转移到细菌细胞。