Construction of the rfaH Gene Deletion Strain in Salmonella anatum and Study of Its Biological Characteristics
SONG Ya-Wen1, GAO Yu-Jie1, ZHANG Xiao-Hui1, WANG Wen-Xin1, GE Tong-Xin1, ZHAI Rui-Dong1, SONG Hou-Hui1, CHENG Chang-Yong1, LI Ai-Yun2,*, HAN Yue1,*
1 College of Animal Science and Technology/College of Veterinary Medicine/Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province/Zhejiang Provincial Engineering Research Center for Animal Health Diagnostics/Advanced Technology, Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management/China-Australia Joint Laboratory for Animal Health Big Data Analytics, Zhejiang A&F University, Hangzhou 311300, China; 2 Women's Hospital School of Medicine Zhejiang University, Hangzhou 310006, China
Abstract：Salmonella anatum is a major pathogen that causes salmonellosis in ducks (Anatidae). rfaH encodes the transcriptional anti-termination factor RfaH, which is essential for bacterial transcription, infection, and other biological functions. This study investigated the effect of the rfaH gene on various biological aspects of S. anatum, including growth, motility, biofilm formation, and cell infection. To deeply understand the biological roles of the rfaH gene in S. anatum, an rfaH gene deletion strain ΔrfaH and the complement strain CΔrfaH derived from the S. anatum isolate strain SA01 were generated using Red homologous recombination technology. The sequencing results showed that the rfaH gene deletion strain ΔrfaH and the complement strain CΔrfaH of SA01 were successfully constructed. After the deletion of the rfbH gene, the growth rate remained unchanged, yet the O-antigen synthesis was impaired, leading to a significant decrease in bacterial motility, an enhancement in biofilm formation, an increased adhesion and invasion capacity against DF-1 cells, and a weakened proliferation ability in RAW264.7 cells. The findings indicated that the rfaH gene was involved in bacterial motility, biofilm formation, and cell infection. This study establishes a solid platform for future research on the biological functions of the rfaH gene and the development of Salmonella-based delivery vectors for vaccine applications.
宋亚雯, 高宇杰, 张晓荟, 王温馨, 葛同鑫, 翟瑞东, 宋厚辉, 程昌勇, 李爱云, 韩月. 鸭沙门菌rfaH基因缺失株的构建及其生物学特性研究[J]. 农业生物技术学报, 2025, 33(3): 642-649.
SONG Ya-Wen, GAO Yu-Jie, ZHANG Xiao-Hui, WANG Wen-Xin, GE Tong-Xin, ZHAI Rui-Dong, SONG Hou-Hui, CHENG Chang-Yong, LI Ai-Yun, HAN Yue. Construction of the rfaH Gene Deletion Strain in Salmonella anatum and Study of Its Biological Characteristics. 农业生物技术学报, 2025, 33(3): 642-649.
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