Host cell-free growth of the Q fever bacterium Coxiella burnetii
Host cell-free growth of the Q fever bacterium Coxiella burnetii
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DOI：
10.1073/pnas.0812074106
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发表时间：
2009-03-17
影响因子：
11.1
通讯作者：
Heinzen, Robert A.
中科院分区：
文献类型：
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作者：
Omsland, Anders;Cockrell, Diane C.;Heinzen, Robert A.
无法在无菌（无宿主细胞）培养条件下繁殖专性细胞内病原体，这造成了严格的实验限制，对理解病原体毒力和疾病机制的进展产生了负面影响。伯内特柯克斯体是人类 Q（Query）热的病原体，是一种专性细胞内细菌病原体，仅在酸化的溶酶体样液泡中复制。为了确定支持 C. burnetii 生长的条件，我们使用表达微阵列、基因组重建和代谢物分型系统地评估了生物体的代谢需求。这导致了一种复杂营养培养基的开发，该培养基可支持 C. burnetii 在 2.5% 氧气环境中大量生长（约 3 log(10)）。重要的是，无菌生长的 C. burnetii 对 Vero 细胞具有高度感染性，并表现出体内生长生物体的发育形式特征。 C.burnetii 的无菌培养将促进该生物体发病机制和遗传学的研究，并有助于开发 Q 热预防药物，例如有效的亚单位疫苗。此外，这里使用的系统方法可能广泛适用于支持其他医学上重要的专性细胞内病原体生长的无菌培养基的开发。
The inability to propagate obligate intracellular pathogens under axenic (host cell-free) culture conditions imposes severe experimental constraints that have negatively impacted progress in understanding pathogen virulence and disease mechanisms. Coxiella burnetii, the causative agent of human Q (Query) fever, is an obligate intracellular bacterial pathogen that replicates exclusively in an acidified, lysosome-like vacuole. To define conditions that support C. burnetii growth, we systematically evaluated the organism's metabolic requirements using expression microarrays, genomic reconstruction, and metabolite typing. This led to development of a complex nutrient medium that supported substantial growth (approximately 3 log(10)) of C. burnetii in a 2.5% oxygen environment. Importantly, axenically grown C. burnetii were highly infectious for Vero cells and exhibited developmental forms characteristic of in vivo grown organisms. Axenic cultivation of C. burnetii will facilitate studies of the organism's pathogenesis and genetics and aid development of Q fever preventatives such as an effective subunit vaccine. Furthermore, the systematic approach used here may be broadly applicable to development of axenic media that support growth of other medically important obligate intracellular pathogens.