Genetic Manipulation of Coxiella burnetii
Genetic Manipulation of Coxiella burnetii
复制标题
DOI：
10.1007/978-94-007-4315-1_13
复制
发表时间：
2012-01-01
期刊：
影响因子：
--
通讯作者：
Beare, Paul A.
中科院分区：
文献类型：
--
作者：
Beare, Paul A.
直到最近，贝氏柯克斯体被视为专性细胞内细菌，完全依赖于真核宿主细胞的生长和研究。其他医学相关的专性细胞内细菌存在于该属的生活方式中，对遗传转化构成了重大障碍。当转化体的生长限于宿主细胞时，对于自由生活的细菌来说简单的程序，例如抗生素选择和克隆，可能非常困难。在宿主细胞中长期传代以扩增小的细胞群会使该过程进一步复杂化。尽管存在这些和其他障碍，但目前至少有基本的系统可用于大多数专性细胞内细菌病原体的遗传转化。这极大地帮助了C. Burnetii是最近发现的一种培养基，其支持生物体在液体中，重要的是在固体培养基上作为克隆菌落的无宿主细胞生长。扩大C.伯内特遗传学工具箱现在包括用于随机突变和单拷贝、位点特异性染色体基因敲入的转座子系统，以及用于异源基因表达和反式互补的穿梭载体。一种可靠的靶向基因失活方法仍然是一个挑战。C.贝氏菌的遗传操作将允许鉴定细胞内寄生和疾病发病机理所必需的基因，并且毫无疑问地激发了对这种研究很少的细菌病原体的新兴趣。
Until very recently, Coxiella burnetii was viewed and studied as an obligate intracellular bacterium that relied exclusively on a eucaryotic host cell for growth. Other medically relevant obligate intracellular bacteria reside in the genera lifestyle presents a significant obstacle to genetic transformation. Procedures that are straightforward with free-living bacteria, such as antibiotic selection and cloning, can be very difficult when growth of transformants is restricted to a host cell. Longterm passage in host cells to expand small transformant populations can further complicate the procedure. Despite these and other obstacles, at least rudimentary systems are currently available for genetic transformation of most obligate intracellular bacterial pathogens. Dramatically aiding the development of new genetic methods for C. burnetii is the recent discovery of a medium that supports host cell-free growth of the organism in liquid, and importantly, on solid media as clonal colonies. The expanded C. burnetii genetics toolbox now includes transposon systems for random mutagenesis and single-copy, site-specific chromosomal gene knock-ins, as well as a shuttle vector for heterologous gene expression and in trans complementation. A reliable method of targeted gene inactivation remains a challenge. Advances in C. burnetii genetic manipulation will allow identification of genes essential for intracellular parasitism and disease pathogenesis, and undoubtedly fuel new interest in this minimally studied bacterial pathogen.