Sivaloganathan Darshan M, Brynildsen Mark P
Program in Quantitative and Computational Biology, Princeton University, Princeton, NJ, USA.
Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA.
BMC Res Notes. 2021 Mar 26;14(1):120. doi: 10.1186/s13104-021-05534-7.
Bacteria are exposed to multiple concurrent antimicrobial stressors within phagosomes. Among the antimicrobials produced, hydrogen peroxide and nitric oxide are two of the most deleterious products. In a previous study, we discovered that when faced with both stressors simultaneously, Escherichia coli prioritized detoxification of hydrogen peroxide over nitric oxide. In this study, we investigated whether such a process was conserved in another bacterium, Pseudomonas aeruginosa.
P. aeruginosa prioritized hydrogen peroxide detoxification in a dose-dependent manner. Specifically, hydrogen peroxide detoxification was unperturbed by the presence of nitric oxide, whereas larger doses of hydrogen peroxide produced longer delays in nitric oxide detoxification. Computational modelling revealed that the rate of nitric oxide consumption in co-treated cultures was biphasic, with cells entering the second phase of detoxification only after hydrogen peroxide was eliminated from the culture.
细菌在吞噬体内会同时受到多种抗菌应激源的影响。在产生的抗菌物质中，过氧化氢和一氧化氮是两种最具有害性的产物。在之前的一项研究中，我们发现，当同时面对这两种应激源时，大肠杆菌会优先对过氧化氢进行解毒，而不是一氧化氮。在本研究中，我们调查了这样一个过程在另一种细菌铜绿假单胞菌中是否保守。
铜绿假单胞菌以剂量依赖的方式优先进行过氧化氢解毒。具体而言，一氧化氮的存在不会干扰过氧化氢解毒，而较大剂量的过氧化氢会使一氧化氮解毒的延迟时间更长。计算模型显示，联合处理培养物中一氧化氮的消耗速率是双相的，细胞只有在培养物中的过氧化氢被清除后才进入第二阶段解毒。
