The effects of upaB deletion and the double/triple deletion of upaB, aatA, and aatB genes on pathogenicity of avian pathogenic Escherichia coli.
Autotransporters (ATs) are associated with pathogenesis of Avian Pathogenic Escherichia coli (APEC). The molecular characterization of APEC ATs can provide insights about their relevance to APEC pathogenesis. Here, we characterized a conventional autotransporter UpaB in APEC DE205B genome. The upaB existed in 41.9 % of 236 APEC isolates and was predominantly associated with ECOR B2 and D. Our studies showed that UpaB mediates the DE205B adhesion in DF-1 cells, and enhances autoaggregation and biofilm formation of fimbria-negative E. coli AAEC189 (MG1655Δfim) in vitro. Deletion of upaB of DE205B attenuates the virulence in duck model and early colonization in the duck lungs during APEC systemic infection. Furthermore, double and triple deletion of upaB, aatA, and aatB genes cumulatively attenuated DE205B adhesion in DF-1 cells, accompanying with decreased 50 % lethal dose (LD50) in duck model and the early colonization in the duck lungs. However, DE205BΔupaB/ΔaatA/ΔaatB might "compensate" the influence of gene deletion by upregulating the expression of fimbrial adhesin genes yqiL, yadN, and vacuolating autotransporter vat during early colonization of APEC. Finally, we demonstrated that vaccination with recombinant UpaB, AatA, and AatB proteins conferred protection against colisepticemia caused by DE205B infection in duck model.
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. zgxiangkai@163.com.
Xiang-Kai
XK
Zhu-Ge
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. 2013207013@njau.edu.cn.
Zi-Hao
ZH
Pan
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. 850421558@qq.com.
Fang
F
Tang
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China. xmao@njau.edu.cn.
Xiang
X
Mao
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. 2013807115@njau.edu.cn.
Lin
L
Hu
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China. 1196820085@qq.com.
Shao-Hui
SH
Wang
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. 1091517919@qq.com.
Bin
B
Xu
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. lucp@njau.edu.cn.
Cheng-Ping
CP
Lu
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. fhj@njau.edu.cn.
Hong-Jie
HJ
Fan
Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural, University, No.1 Weigang road, Nanjing, Jiangsu Province, 210095, China. daijianjun@njau.edu.cn.
Jian-Jun
JJ
Dai
D000818:Animals; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D001715:Bird Diseases / Q000382:microbiology / Q000473:pathology*; D004372:Ducks; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D007928:Lethal Dose 50; D008168:Lung / Q000382:microbiology; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics*
C512825:AatA protein, E coli; C000610438:AatB protein, E coli; D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; C569987:UpaB protein, E coli; D037521:Virulence Factors
APEC; Autotransporter UPAB; Double/triple deletion; Pathogenicity; Vaccination