Effects of ibeA deletion on virulence and biofilm formation of avian pathogenic Escherichia coli.
The ibeA gene is located on a genomic island, GimA, which is involved in the pathogenesis of neonatal meningitis Escherichia coli (NMEC) and avian pathogenic E. coli (APEC). The prevalence of ibeA in the APEC collection in China was investigated, and 20 of 467 strains (4.3%) were positive. In addition, analysis of the association of the E. coli reference (ECOR) groups with positive strains revealed that ibeA was linked to group B2. The ibeA gene in DE205B was analyzed and compared to those of APEC and NMEC, which indicated that the specificity of ibeA was not consistent along pathotypes. The invasion of chicken embryo fibroblast DF-1 cells by APEC DE205B and RS218 was observed, which suggested that DF-1 cells could be a model to study the mechanism of APEC invasion. The inactivation of ibeA in APEC DE205B led to the reduced capacity to invade DF-1 cells, defective virulence in vivo, and decreased biofilm formation compared to the wild-type strain. In addition, strain AAEC189 expressing ibeA exhibited enhanced invasion capacity and biofilm formation. The results of the quantitative real-time reverse transcription-PCR (qRT-PCR) analysis and animal system infection experiments indicated that the loss of ibeA decreased the colonization and proliferation capacities of APEC in the brain during system infection.
Key Laboratory of Animal Disease Diagnostics and Immunology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China.
Shaohui
S
Wang
Chunling
C
Niu
Zhenyu
Z
Shi
Yongjie
Y
Xia
Muhammad
M
Yaqoob
Jianjun
J
Dai
Chengping
C
Lu
D000818:Animals; D018441:Biofilms / Q000254:growth & development*; D002460:Cell Line; D002642:Chick Embryo; D004372:Ducks; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D011201:Poultry Diseases / Q000382:microbiology*; D014774:Virulence
C096350:CusC protein, E coli; D029968:Escherichia coli Proteins; D008565:Membrane Proteins