Identification of novel genes essential for Brucella abortus to establish infection by signature-tagged mutagenesis
Identification of novel genes essential for Brucella abortus to establish infection by signature-tagged mutagenesis
复制标题
通过特征标记诱变鉴定流产布鲁氏菌建立感染所必需的新基因
DOI：
10.1016/j.vetmic.2019.02.005
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发表时间：
2019-03-01
影响因子：
3.3
通讯作者：
Yu, Shengqing
中科院分区：
文献类型：
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作者：
Tian, Mingxing;Qu, Jing;Yu, Shengqing
布鲁氏菌是一种兼性胞内菌，可引发布鲁氏菌病，这是一种在世界范围内重要的人畜共患病。布鲁氏菌没有经典的毒力因子，因此其毒力依赖于对宿主细胞的入侵以及随后在细胞内的复制。鉴定参与布鲁氏菌毒力的关键基因对于进一步阐明其发病机制非常重要。在本研究中，采用标记标签诱变技术在小鼠模型中鉴定参与牛布鲁氏菌感染的新基因。共获得3600个突变体，其中56个被鉴定为减毒突变体。此外，通过转座子插入确定有53个基因失活，包括19个先前报道的对布鲁氏菌毒力至关重要的基因以及本研究新鉴定的34个基因。这些基因被归类为16种功能类别，但有3个基因未在直系同源簇数据库中被引用。生物信息学分析显示，能量产生和转换、氨基酸转运和代谢以及无机离子转运和代谢是主要的功能类别，这表明参与这些功能的基因对布鲁氏菌毒力至关重要。此外，利用等位基因替换的丙酮酸羧化酶（pyc）突变体和小鼠模型证实了所鉴定的丙酮酸羧化酶基因在细菌毒力中的作用。这些发现提供了与布鲁氏菌感染相关的新基因信息。
Brucella is a facultative intracellular bacterium, causing brucellosis, an important zoonosis worldwide. Brucella has no classic virulence factors, thus virulence is dependent on invasion of host cells and subsequent intracellular replication. Identification of key genes involved in Brucella virulence is important to further elucidate its pathogenesis. In this study, signature-tagged mutagenesis was used to identify novel genes involved in B. abortus infection in a mouse model. In total 3600 mutants were obtained, of which 56 were identified as attenuated mutants. Furthermore, 53 genes were identified to be inactivated by transposon insertion, including 19 genes previously reported to be essential for Brucella virulence and 34 others that were newly identified in this study. These genes were catalogued into 16 functional classifications, except for three that were not cited in the Clusters of Orthologous Groups database. Bioinformatics analysis revealed that energy production and conversion, amino acid transport and metabolism, as well as inorganic ion transport and metabolism were predominant functional classifications, suggesting that genes involved in these functions were crucial for Brucella virulence. In addition, the function of the identified pyruvate carboxylase (pyc) gene in bacterial virulence was confirmed using an allelic replacement pyc mutant and a mouse model. These findings provide novel genetic information associated with Brucella infection.