In vivo bioluminescence imaging of Escherichia coli O104:H4 and role of aerobactin during colonization of a mouse model of infection.
In vivo bioluminescence imaging of Escherichia coli O104:H4 and role of aerobactin during colonization of a mouse model of infection.
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DOI：
10.1186/1471-2180-12-112
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发表时间：
2012-06-20
期刊：
影响因子：
4.2
通讯作者：
Popov VL
中科院分区：
文献类型：
--
作者：
Torres AG;Cieza RJ;Rojas-Lopez M;Blumentritt CA;Souza CS;Johnston RK;Strockbine N;Kaper JB;Sbrana E;Popov VL
2011 年初，爆发了与产志贺毒素大肠杆菌 O104:H4 相关的血性腹泻大暴发，与异常数量的溶血性尿毒症综合征病例相关。由于有关该特定血清型的发病机制和/或毒力特性的信息有限，我们研究了需氧菌素铁转运系统在体外和体内条件下的贡献。使用生物发光报告构建体对小鼠感染模型中的大肠杆菌 O104:H4 进行实时监测。我们验证了我们的报告菌株保持了与野生型大肠杆菌菌株相似的特征和生长动力学。我们发现 ICR (CD-1) 小鼠的肠道盲肠被 O104:H4 定植，并且细菌在胃内接种后持续存在长达 7 天。对热提取的蛋白质进行 MALDI-TOF 分析，以确定假定的表面暴露毒力决定因素。鉴定出一种与 aerobactin 铁受体高度相似的蛋白质，并进一步证明，当在麦康凯琼脂上或缺铁条件下生长时，该蛋白质在大肠杆菌 O104:H4 中上调。由于需氧菌素铁获取系统是肠杆菌科的关键毒力因子，因此创建了同基因需氧菌素受体 (iutA) 突变体，并在小鼠模型中评估了其肠道适应性。我们证明，在体内竞争实验中，aerobactin 突变体在竞争中被野生型大肠杆菌 O104:H4 击败，并且该突变体无法在盲肠中持续存在。我们的研究结果表明，生物发光成像是监测大肠杆菌 O104:H4 定植特性的有用工具，而小鼠模型可以成为评估大肠杆菌 O104:H4 感染期间与健康和/或定植相关的细菌因素的快速方法。
A major outbreak of bloody diarrhea associated with Shiga toxin-producing Escherichia coli O104:H4 occurred early in 2011, to which an unusual number of hemolytic uremic syndrome cases were linked. Due to limited information regarding pathogenesis and/or virulence properties of this particular serotype, we investigated the contribution of the aerobactin iron transport system during in vitro and in vivo conditions. A bioluminescent reporter construct was used to perform real-time monitoring of E. coli O104:H4 in a mouse model of infection. We verified that our reporter strain maintained characteristics and growth kinetics that were similar to those of the wild-type E. coli strain. We found that the intestinal cecum of ICR (CD-1) mice was colonized by O104:H4, with bacteria persisting for up to 7 days after intragastric inoculation. MALDI-TOF analysis of heat-extracted proteins was performed to identify putative surface-exposed virulence determinants. A protein with a high similarity to the aerobactin iron receptor was identified and further demonstrated to be up-regulated in E. coli O104:H4 when grown on MacConkey agar or during iron-depleted conditions. Because the aerobactin iron acquisition system is a key virulence factor in Enterobacteriaceae, an isogenic aerobactin receptor (iutA) mutant was created and its intestinal fitness assessed in the murine model. We demonstrated that the aerobactin mutant was out-competed by the wild-type E. coli O104:H4 during in vivo competition experiments, and the mutant was unable to persist in the cecum. Our findings demonstrate that bioluminescent imaging is a useful tool to monitor E. coli O104:H4 colonization properties, and the murine model can become a rapid way to evaluate bacterial factors associated with fitness and/or colonization during E. coli O104:H4 infections.
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影响因子：
2.8
作者：
Brzuszkiewicz, Elzbieta;Thuermer, Andrea;Schuldes, Joerg;Leimbach, Andreas;Liesegang, Heiko;Meyer, Frauke-Dorothee;Boelter, Juergen;Petersen, Heiko;Gottschalk, Gerhard;Daniel, Rolf
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Daniel, Rolf
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3.6
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3.1
作者：
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影响因子：
2.2
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通讯作者：
Torres AG