Paulander Wilhelm, Wang Ying, Folkesson Anders, Charbon Godefroid, Løbner-Olesen Anders, Ingmer Hanne
Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark.
Department of Microbial Ecology and Animal health, Technical University of Denmark, Frederiksberg C, Denmark.
PLoS One. 2014 Mar 19;9(3):e92231. doi: 10.1371/journal.pone.0092231. eCollection 2014.
It was recently proposed that for bactericidal antibiotics a common killing mechanism contributes to lethality involving indirect stimulation of hydroxyl radical (OH•) formation. Flow cytometric detection of OH• by hydroxyphenyl fluorescein (HPF) probe oxidation was used to support this hypothesis. Here we show that increased HPF signals in antibiotics-exposed bacterial cells are explained by fluorescence associated with increased cell size, and do not reflect reactive oxygen species (ROS) concentration. Independently of antibiotics, increased fluorescence was seen for elongated cells expressing the oxidative insensitive green fluorescent protein (GFP). Although our data question the role of ROS in lethality of antibiotics other research approaches point to important interplays between basic bacterial metabolism and antibiotic susceptibility. To underpin such relationships, methods for detecting bacterial metabolites at a cellular level are needed.
最近有人提出，对于杀菌性抗生素，一种常见的杀伤机制导致致死性，这涉及间接刺激羟基自由基（OH•）的形成。使用羟基苯基荧光素（HPF）探针氧化法通过流式细胞术检测OH•来支持这一假设。在此我们表明，暴露于抗生素的细菌细胞中HPF信号的增加是由与细胞大小增加相关的荧光所解释的，并不反映活性氧（ROS）浓度。与抗生素无关，对于表达对氧化不敏感的绿色荧光蛋白（GFP）的细长细胞，也观察到荧光增加。尽管我们的数据质疑了ROS在抗生素致死性中的作用，但其他研究方法表明基本细菌代谢与抗生素敏感性之间存在重要的相互作用。为了巩固这种关系，需要在细胞水平检测细菌代谢物的方法。
