Coevolution of furA-Regulated Hyper-Inflammation and Mycobacterial Resistance to Oxidative Killing through Adaptation to Hydrogen Peroxide.
Coevolution of furA-Regulated Hyper-Inflammation and Mycobacterial Resistance to Oxidative Killing through Adaptation to Hydrogen Peroxide.
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DOI：
10.1128/spectrum.05367-22
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发表时间：
2023-08-17
影响因子：
3.7
通讯作者：
中科院分区：
文献类型：
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结核分枝杆菌（Mycobacterium tuberculosis，Mtb）对宿主的氧化杀伤具有高度抗性。我们假设M.过氧化氢（H2 O2）的污染会使非致病性分枝杆菌在宿主体内持续存在。在本研究中，我们通过体外进化H2 O2适应筛选出一个高度抗H2 O2的菌株（mc 2114）。mc 2114对H2 O2的MIC是野生型mc 2155的320倍。小鼠感染实验表明，mc 2114类似于Mtb，在肺中持续存在，并在小鼠中引起高致死率，肺中NOX 2、ROS、IFN-γ的反应受限，巨噬细胞凋亡减少，炎性细胞因子过表达。全基因组测序分析显示，mc 2114在多个基因中具有29个单核苷酸多态性;其中一个是在furA基因上，该基因导致FurA缺陷介导的KatG过表达，KatG是一种过氧化氢酶-过氧化物酶，可以解毒ROS。mc 2114与野生型furA基因的互补逆转了KatG和炎性细胞因子过度表达的小鼠的致死性和过度炎症反应，而NOX 2、ROS、IFN-γ和巨噬细胞凋亡仍然减少。结果表明，虽然FurA调控KatG的表达，它并没有显着的ROS反应的限制。相反，FurA缺乏导致有害的肺部炎症，导致感染的严重程度，这是以前未认识到的FurA在分枝杆菌发病机制中的功能。该研究还表明，分枝杆菌对氧化爆发的抗性来自复杂的机制，涉及多个基因的适应性遗传变化。结核分枝杆菌（Mtb）导致人类结核病（TB），在人类历史上，结核病比任何其他微生物都要多。然而，Mtb发病机制和相关基因尚未完全阐明，这阻碍了遏制和根除TB的有效策略的发展。在本研究中，我们构建了一个M.通过用H2 O2进行适应性进化筛选，获得了具有多个突变的smeglobulin（mc 2114）。其中一个furA突变导致FurA缺陷，通过过度表达炎性细胞因子介导严重的炎性肺损伤和小鼠更高的致死率。我们的研究结果表明，除了已知的NOX 2、ROS、IFN-γ反应和巨噬细胞凋亡的下调外，FurA调节的肺部炎症在分枝杆菌发病机制中起关键作用。对mc 2114突变的进一步分析将确定更多与致病性增加相关的基因，并有助于制定遏制和根除结核病的新策略。
Mycobacterium tuberculosis (Mtb) is highly resistant to host oxidative killing. We hypothesized that the evolutionary adaptation of M. smegmatis to hydrogen peroxide (H2O2) would endow the nonpathogenic Mycobacterium persistent in a host. In the study, we screened a highly H2O2-resistant strain (mc2114) via evolutionary H2O2 adaptation in vitro. The MIC of mc2114 to H2O2 is 320 times that of wild-type mc2155. Mouse infection experiments showed that mc2114, similar to Mtb, was persistent in the lungs and caused high lethality in mice with restricted responses of NOX2, ROS, IFN-γ, decreased macrophage apoptosis, and overexpressed inflammatory cytokines in the lungs. Whole-genome sequencing analysis revealed that mc2114 harbored 29 single nucleotide polymorphisms in multiple genes; one of them was on the furA gene that caused FurA deficiency-mediated overexpression of KatG, a catalase-peroxidase to detoxify ROS. Complementation of mc2114 with a wild-type furA gene reversed lethality and hyper-inflammatory response in mice with rescued overexpression of KatG and inflammatory cytokines, whereas NOX2, ROS, IFN-γ, and macrophage apoptosis remained reduced. The results indicate that although FurA regulates KatG expression, it does not contribute significantly to the restriction of ROS response. Instead, FurA deficiency is responsible for the detrimental pulmonary inflammation that contributes to the severity of the infection, a previously nonrecognized function of FurA in mycobacterial pathogenesis. The study also indicates that mycobacterial resistance to oxidative burst results from complex mechanisms involving adaptive genetic changes in multiple genes. IMPORTANCE Mycobacterium tuberculosis (Mtb) causes human tuberculosis (TB), which has killed more people in human history than any other microorganism. However, the mechanisms underlying Mtb pathogenesis and related genes have not yet been fully elucidated, which impedes the development of effective strategies for containing and eradicating TB. In the study, we generated a mutant of M. smegmatis (mc2114) with multiple mutations by an adaptive evolutionary screen with H2O2. One of the mutations in furA caused a deficiency of FurA, which mediated severe inflammatory lung injury and higher lethality in mice by overexpression of inflammatory cytokines. Our results indicate that FurA-regulated pulmonary inflammation plays a critical role in mycobacterial pathogenesis in addition to the known downregulation of NOX2, ROS, IFN-γ responses, and macrophage apoptosis. Further analysis of the mutations in mc2114 would identify more genes related to the increased pathogenicity and help in devising new strategies for containing and eradicating TB.
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影响因子：
7.4
作者：
Circu, Magdalena L.;Aw, Tak Yee
通讯作者：
Aw, Tak Yee
DOI：
10.1038/s41579-022-00763-4
发表时间：
2022-12
期刊：
Nature reviews. Microbiology
影响因子：
--
作者：
通讯作者：
--
DOI：
10.1007/978-1-4939-8570-8_3
发表时间：
2018
期刊：
Methods in molecular biology (Clifton, N.J.)
影响因子：
--
作者：
Gibbings SL;Jakubzick CV
通讯作者：
Jakubzick CV
影响因子：
3.1
作者：
Kee, Seung-Jung;Kwon, Yong-Soo;Ryang, Dong-Wook
通讯作者：
Ryang, Dong-Wook
影响因子：
8.6
作者：
Kawai, Toshinao;Watanabe, Nobuyuki;Onodera, Masafumi
通讯作者：
Onodera, Masafumi