Two-pronged survival strategy for the major cystic fibrosis pathogen, Pseudomonas aeruginosa, lacking the capacity to degrade nitric oxide during anaerobic respiration.
Two-pronged survival strategy for the major cystic fibrosis pathogen, Pseudomonas aeruginosa, lacking the capacity to degrade nitric oxide during anaerobic respiration.
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针对主要囊性纤维化病原体铜绿假单胞菌的双管齐下的生存策略，该病原体在无氧呼吸过程中缺乏降解一氧化氮的能力。
DOI：
10.1038/sj.emboj.7601787
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Hassett,Dani
中科院分区：
文献类型：
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作者：
Yoon,SangSun;Karabulut,AhmetC;Lipscomb,JohnD;Hennigan,RobertF;Lymar,SergeiV;Groce,StephanieL;Herr,AndrewB;Howell,MichaelL;Kiley,PatriciaJ;Schurr,MichaelJ;Gaston,Benjamin;Choi,Kyoung-Hee;Schweizer,HerbertP;Hassett,Dani
Protection from NO gas, a toxic byproduct of anaerobic respiration inPseudomonas aeruginosa, is mediated by nitric oxide (NO) reductase (NOR), thenorCBgene product. Nevertheless, anorCBmutant that accumulated ∼13.6 μM NO paradoxically survived anaerobic growth. Transcription of genes encoding nitrate and nitrite reductases, the enzymes responsible for NO production, was reduced >50‐ and 2.5‐fold in thenorCBmutant. This was due, in part, to a predicted compromise of the [4Fe–4S]2+cluster in the anaerobic regulator ANR by physiological NO levels, resulting in an inability to bind to its cognate promoter DNA sequences. Remarkably, two O2‐dependent dioxygenases,homogentisate‐1,2‐dioxygenase (HmgA) and 4‐hydroxyphenylpyruvatedioxygenase (Hpd), were derepressed in thenorCBmutant. Electron paramagnetic resonance studies showed that HmgA and Hpd bound NO avidly, and helped protect thenorCBmutant in anaerobic biofilms. These data suggest that protection of aP. aeruginosa norCBmutant against anaerobic NO toxicity occurs by both control of NO supply and reassignment of metabolic enzymes to the task of NO sequestration.
