1
|
Jin M, He J, Li J, Hu Y, Sun D, Gu H. Edwardsiella piscicida YccA: A novel virulence factor essential to membrane integrity, mobility, host infection, and host immune response. Fish Shellfish Immunol 2022; 126:318-326. [PMID: 35654386 DOI: 10.1016/j.fsi.2022.05.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 05/16/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
YccA is a hydrophobic protein with seven transmembrane domains. The function of YccA is largely unknown in pathogenic bacteria. Edwardsiella piscicide (formerly known as E. tarda) is an aquatic pathogen that can infect various economically important fish, including flounder (Paralichthys olivaceus) and tilapia (Oreochromis niloticus). In this study, we investigated the role of YccA in E. piscicida by the construction of a mar kerless yccA in-frame mutant strain, TX01ΔyccA. We found that (i) in comparison to the wild type TX01, TX01ΔyccA exhibited markedly compromised tolerance to high temperature and tobramycin; (ii) deletion of yccA significantly impaired the integrity of the cell membrane and retarded bacterial biofilm formation and mobility; (iii) deficiency of yccA reduced bacterial adhesion and invasion of fish cells and immune tissues, while the introduction of a trans-expressed yccA gene restored the lost virulence of TX01ΔyccA; and (iv) host immune responses induced by TX01 and TX01ΔyccA were different in terms of reactive oxygen species (ROS) levels and expression levels of cytokines. Taken together, the results of our study indicate that YccA is a novel virulence factor of E. piscicida, and YccA is essential for bacterial pathogenicity through evasion of the host's innate immune functions.
Collapse
Affiliation(s)
- Mengru Jin
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163319, China; Institute of Tropical Bioscience and Biotechnology, Hainan Academy of Tropical Agricultural Resource, CATAS, Haikou, 571101, China
| | - Jiaojiao He
- Institute of Tropical Bioscience and Biotechnology, Hainan Academy of Tropical Agricultural Resource, CATAS, Haikou, 571101, China; School of Life Sciences, Hainan University, Haikou, 570228, China
| | - Jun Li
- School of Science and Medicine, Lake Superior State University, Sault Ste. Marie, Michigan, 49783, USA
| | - Yonghua Hu
- Institute of Tropical Bioscience and Biotechnology, Hainan Academy of Tropical Agricultural Resource, CATAS, Haikou, 571101, China; Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, 266071, China; Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources, Haikou, 571101, China
| | - Dongmei Sun
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University, Daqing, 163319, China.
| | - Hanjie Gu
- Institute of Tropical Bioscience and Biotechnology, Hainan Academy of Tropical Agricultural Resource, CATAS, Haikou, 571101, China; Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources, Haikou, 571101, China.
| |
Collapse
|