The role of the outer membrane protein gene ybjX in the pathogenicity of avian pathogenic Escherichia coli
The role of the outer membrane protein gene ybjX in the pathogenicity of avian pathogenic Escherichia coli
复制标题
外膜蛋白基因ybjX在禽致病性大肠杆菌致病性中的作用
DOI：
10.1080/03079457.2018.1448053
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发表时间：
2018-01-01
期刊：
影响因子：
2.8
通讯作者：
Xue, Ting
中科院分区：
文献类型：
--
作者：
Song, Xiangjun;Li, Chunxiao;Xue, Ting
ABSTRACT Avian pathogenic Escherichia coli (APEC) are important pathogens that cause serious economic losses to the poultry industry worldwide. The PhoP/Q system is essential for APEC pathogenicity, and its mutation leads to a decrease in ybjX gene expression, but whether ybjX regulated by PhoP/Q plays a role in pathogenicity remains unclear. The role of ybjX in APEC pathogenicity was investigated using a ybjX mutant strain constructed from APEC strain AE17 by the Red recombination method. The mutant strain displayed significantly reduced adherence to and invasion of chicken embryo fibroblast cell line (DF-1) cells. Moreover, N-phenyl-1-naphthylamine (NPN) assays revealed an increase in outer membrane permeabilization for the ybjX mutant, suggesting ybjX affected susceptibility to avian beta-defensin through this mechanism. The ybjX mutation increased susceptibility to avian beta-defensin 9 (AvBD9), and in vivo LD50 assays revealed reduced bacterial virulence in a chicken model. Taken together, these results indicated that mutation of ybjX may attenuate APEC pathogenicity, not only by affecting bacterial adhesion and invasion, but also via reducing resistance to avian beta-defensin by increasing outer membrane permeabilization of bacteria.
