Transposon mutagenesis identifies the sspA-sspB operon as essential for serum resistance and virulence in avian pathogenic Escherichia coli.

Autor: Gao Q; Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, PR China; Institutes of Agricultural Science and Technology Development, Yangzhou University, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China., Xing Q; Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, PR China; Institutes of Agricultural Science and Technology Development, Yangzhou University, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China., Sun Y; Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, PR China; Institutes of Agricultural Science and Technology Development, Yangzhou University, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China., Li Z; Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, PR China; Institutes of Agricultural Science and Technology Development, Yangzhou University, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China., Gao S; Key Laboratory of Avian Bioproduct Development, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China; College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu 225009, PR China; Institutes of Agricultural Science and Technology Development, Yangzhou University, Ministry of Agriculture and Rural Affairs, Yangzhou, Jiangsu 225009, PR China. Electronic address: gsong@yzu.edu.cn.
Jazyk: angličtina
Zdroj: Veterinary microbiology [Vet Microbiol] 2024 Dec 20; Vol. 301, pp. 110345. Date of Electronic Publication: 2024 Dec 20.
DOI: 10.1016/j.vetmic.2024.110345
Abstrakt: Avian pathogenic Escherichia coli (APEC) constitutes a significant threat to poultry health worldwide, causing colibacillosis and inflicting substantial economic losses. The ability to resist serum-mediated killing is a key virulence factor enabling APEC to circumvent the host immune system and establish systemic infection. In this study, we employed mariner-based transposon mutagenesis to generate a mutant library of APEC strain E058 and screened for mutants with reduced serum resistance. We identified a transposon insertion within the sspB gene of the sspA-sspB operon that conferred significantly reduced serum resistance. Targeted gene knockout experiments confirmed that both sspA and sspB contribute to serum resistance, with the double mutant (ΔsspAΔsspB) displaying a more pronounced susceptibility to serum compared to the single gene knockouts (ΔsspA and ΔsspB). Furthermore, in vivo challenge experiments in chickens demonstrated that disruption of the sspA-sspB operon significantly attenuated APEC virulence. Our study also reveals that the sspA-sspB operon plays a role in biofilm formation and promotes intracellular survival within macrophages, suggesting a multifaceted contribution to APEC pathogenesis. These findings highlight the sspA-sspB operon as a promising target for the development of novel therapeutics against APEC infections in poultry.
Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest.
(Copyright © 2024. Published by Elsevier B.V.)
Databáze: MEDLINE
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