摘要

       在生物电化学反应器（BERs）中，在电解刺激下，耐药细菌（ARB）及其相关的耐药基因（ARG）的表达去向尚不清楚。在本研究中，从误码率中分离出抗磺胺嘧啶细菌（Klebsiella spp），并在模拟误码率中接受恒定直流电（DC）刺激。当电流从7～28毫安时，发现乳酸脱氢酶（LDH）在48小时时比对照组高1.03-、1.21-、1.34-、1.46倍，说明细胞膜通透性增加。随着三磷酸腺苷（ATP）浓度的增加，克雷伯氏菌的比生长速率增加（R = 0.98）。克雷伯菌活菌数在19 mA时达到最大值，随后下降。流式细胞仪分析显示ARB的致死率在48小时由18%（7 mA）上升到37.8%（28 mA）。电解水产生的活性氧种类（ROS）随着电流的增加而增加（R =0.94），这可能是克雷伯氏菌致死率高的原因。。扫描电镜结果表明，电刺激改变了细胞表面形态，并有一定程度的细胞分裂。观察到sulII和int1表达上调。观察到int1与电流（R = 0.97）显著相关。综上所述，BERs在加速ARB增殖和促进ARG表达方面具有潜在的风险。

       The fate of antibiotic-resistant bacteria (ARB) and associated antibiotic-resistant gene (ARG) expression under electrolytic stimulation in bio-electrochemical reactors (BERs) was unknown. In this study, sulfadiazine resistant bacteria (Klebsiella spp.), which were isolated from a BER, were subjected to constant direct current (DC) stimulation in a simulated BER. With an increase of the current from 7 to 28 mA, it was found that lactic dehydrogenase (LDH) showed a 1.03-, 1.21-, 1.34-, and 1.46-fold value compared with the control at 48 h, indicating that the cell membrane permeability had increased. Since the adenosine triphosphate (ATP) concentration increased with the current, the specific growth rate of Klebsiella spp. increased (R = 0.98). The viable count of Klebsiella spp. reached a maximum at 19 mA and then decreased. The percentage of ARB lethality, which was reflected by flow cytometry analysis, increased from 18% (7 mA) to 37.8% (28 mA) at 48 h. Reactive oxygen species (ROS) produced from the electrolysis of water were greater with the increasing current (R = 0.94), which may be responsible for the high lethality rate of Klebsiella spp.. Scanning electronic microscope results showed that electrolytic stimulation changed the cell surface morphology with some cell disruption. An upregulation of sulII and int1 expression was observed. A significant correlation between int1 and the current (R = 0.97) were observed. Taken together, BERs possess potential risks in accelerating ARB multiplication and promoting ARG expression.

         https://linkinghub.elsevier.com/retrieve/pii/S0045-6535(17)32154-9