尽管已经广泛研究了有效氧化剂种类的鉴定,然而,在电化学消毒过程中,细菌灭活的亚细胞机制从未被清楚地阐明。在这项研究中,从细胞形态等综合因素揭示了电化学消毒过程中大肠杆菌失活的亚细胞机制,总有机成分,K(+)泄漏,膜渗透性,脂质过氧化,膜电位,膜蛋白,胞内酶,细胞ATP水平和DNA。电解是用掺硼的金刚石阳极在三种电解质中进行的,包括氯化物,硫酸盐和磷酸盐。结果表明,细胞失活主要归因于氯化物溶液中细胞内酶系统的破坏。在硫酸盐溶液中,消除了某些必需的膜蛋白,例如K()离子转运系统。因此,从细胞质中明显的K()泄漏导致膜电位逐渐崩溃,这将阻碍细胞分裂相关蛋白的亚细胞定位以及ATP合成,从而导致细菌失活。观察到明显的脂质过氧化,而细胞内损伤可以忽略不计。在磷酸盐溶液中,细胞作为一个没有被捕获的中间状态的完整细胞依次经历了整体破坏,在此期间,细胞的有机成分大多受到矿化。这项研究提供了在亚细胞水平上对细菌灭活机制的全面了解。
Although the identification of effective oxidant species has been extensively studied, yet the subcellular mechanism of bacterial inactivation has never been clearly elucidated in electrochemical disinfection processes. In this
study, subcellular mechanism of Escherichia coli inactivation during electrochemical disinfection was revealed in terms of comprehensive factors such as cell morphology, total organic components, K(+) leakage, membrane permeability, lipid peroxidation, membrane potential, membrane proteins, intracellular enzyme, cellular ATP level and DNA. The electrolysis was conducted with boron-doped diamond anode in three electrolytes including chloride, sulfate and phosphate. Results demonstrated that cell inactivation was mainly attributed to damage to the intracellular enzymatic systems in chloride solution. In sulfate solution, certain essential membrane proteins like the K(+) ion transport systems were eliminated. Thus, the pronounced K(+) leakage from cytosol resulted in gradual collapse of the membrane potential, which would hinder the subcellular localization of cell division-related proteins as well as ATP synthesis and thereby lead to the bacterial inactivation. Remarkable lipid peroxidation was observed, while the intracellular damage was negligible. In phosphate solution, the cells sequentially underwent overall destruction as a whole cell with no captured intermediate state, during which the organic components of the cells were mostly subjected to mineralization. This
study provided a thorough insight into the bacterial inactivation mechanism on the subcellular level.