Department of Chemistry, University of Texas at Austin, 1 University Station, Stop A5300, Austin, TX, 78712, USA.
Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Bolshoi Boulevard 30 Bld. 1, Moscow, 121205, Russia.
Biosens Bioelectron. 2019 Oct 1;142:111538. doi: 10.1016/j.bios.2019.111538. Epub 2019 Jul 25.
The opportunistic human pathogen Pseudomonas aeruginosa (Pa) causes several infections acquired in a healthcare setting. During initial stages of infection, Pa produces redox-active phenazine metabolites, including pyocyanin (PYO), 5-methylphenazine-1-carboxylic acid (5-MCA), and 1-hydroxyphenazine (OHPHZ), which have toxic effects on surrounding host cells and/or other microbes. Rapid and sensitive detection of these metabolites provides important evidence about the onset of Pa infections. Herein, we investigate differences in Pa phenazine production and dynamics in polymicrobial communities. Specifically, Pa was co-cultured with two pathogens of clinical relevance, Staphylococcus aureus (Sa) and Escherichia coli (Ec), which typically populate infection sites with Pa. Phenazine production rates and biosynthesis dynamics were electrochemically monitored during a 48-h period using recently developed transparent carbon ultramicroelectrode arrays (T-CUAs). Moreover, the effect on phenazine production rates and dynamics was explored in two growth media, lysogeny broth (LB) and tryptic soy broth (TSB). The concentrations of PYO and highly reactive 5-MCA were determined in different polymicrobial culture samples in both media. The results demonstrate that other bacterial pathogens noticeably influence Pa phenazine production and dynamics. In particular, Sa caused a decrease in phenazine production in TSB. However, the presence of Ec in polymicrobial samples drastically inhibited phenazine production rates in both LB and TSB. Conclusively, the media type significantly influences phenazine product distribution, especially in polymicrobial co-cultures, signifying the need for analytical standardization of simulation media in the study of polymicrobial communities.
机会性病原体铜绿假单胞菌(Pa)会导致在医疗环境中获得的几种感染。在感染的初始阶段,Pa 会产生氧化还原活性的吩嗪代谢物,包括绿脓菌素(PYO)、5-甲基吩嗪-1-羧酸(5-MCA)和 1-羟基吩嗪(OHPHZ),这些代谢物对周围宿主细胞和/或其他微生物具有毒性作用。这些代谢物的快速和敏感检测为 Pa 感染的发生提供了重要证据。在此,我们研究了多微生物群落中 Pa 吩嗪产生和动态的差异。具体而言,将 Pa 与两种具有临床相关性的病原体金黄色葡萄球菌(Sa)和大肠杆菌(Ec)共培养,这两种病原体通常与 Pa 一起定植感染部位。使用最近开发的透明碳超微电极阵列(T-CUAs),在 48 小时的时间内电化学监测吩嗪的产生速率和生物合成动力学。此外,还在两种生长培养基(LB 和 TSB)中探索了对吩嗪产生速率和动力学的影响。在两种培养基的不同多微生物培养样品中测定了 PYO 和高反应性 5-MCA 的浓度。结果表明,其他细菌病原体明显影响 Pa 吩嗪的产生和动态。特别是,Sa 在 TSB 中导致吩嗪产生减少。然而,在多微生物样品中存在 Ec 会在 LB 和 TSB 中极大地抑制吩嗪产生速率。总之,培养基类型对吩嗪产物分布有显著影响,尤其是在多微生物共培养物中,这表明在多微生物群落研究中需要对模拟培养基进行分析标准化。