文献类型：期刊文献

英文题名：Trehalose biosynthesis is important for virulence and granuloma formation by Nocardia seriolae in fish

作者：Chen, Jianlin[1];Weng, Tingting[1];Cai, Wenlong[2,3];Ji, Ziyuan[1];Chen, Yubeng[1];Lu, Yishan[1];Xia, Liqun[1]

机构：[1]Guangdong Ocean Univ, Shenzhen Inst Guangdong Ocean Univ, Guangdong Prov Key Lab Aquat Anim Dis Control & Hl, Fisheries Coll, Zhanjiang, Guangdong, Peoples R China;[2]City Univ Hong Kong, State Key Lab Marine Environm Hlth, Hong Kong, Peoples R China;[3]City Univ Hong Kong, Dept Infect Dis & Publ Hlth, Hong Kong, Peoples R China

年份：2026

卷号：619

外文期刊名：AQUACULTURE

收录：SCI-EXPANDED(收录号：WOS:001715128900001)、、WOS

基金：This work was supported by the Shenzhen Science and Technology Program (JCYJ20240813111703005; JCYJ20250604174217022) , the Guangdong Basic and Applied Basic Research Foundation (2024A1515012674; 2024A1515010074) , Guangxi Key Research and Development Program (Project No. Guike nong AB2506910041) .

语种：英文

外文关键词：Trehalose; Nocardia seriolae; Pathogenicity; Gene knockout; Synthesis pathway

外文摘要：The recent emergence of Nocardia seriolae as a major global aquaculture has affected numerous marine and freshwater fish species, yet the drivers of its emergence remain poorly understood. In this study, trehalose biosynthesis genes of N. seriolae including trehalose-6-phosphate phosphatase synthase (tpp), trehalose synthase (treS) and maltooligosyl-trehalose trehalohydrolase (treZ) were identified to construct corresponding knockout mutants Delta tpp, Delta treS and Delta treZ. These mutants exhibited significantly reduced intracellular trehalose accumulation which directly impaired their growth rates, reflecting reduction in apoptosis and mortality of snakehead (Channa argus) than that of wild-type strain. In fish infected with the wild-type strain, significant upregulation of pro-inflammatory genes (tnf-alpha, il-1 beta and mip-2 alpha) and marked granuloma formation were observed in immune tissues. In contrast, infection with mutants resulted in muted inflammation and an absence of granuloma pathology. However, exogenous trehalose administration restored the virulence phenotypes, including growth, inflammatory induction, apoptosis, mortality, and granuloma formation in the mutant strain to wild-type strain levels, indicating that although the mutants are deficient in trehalose synthesis, they can metabolize exogenous trehalose to regain pathogenicity. Collectively, our findings suggest that dietary trehalose supplementation in aquaculture may contribute to the emergence and virulence of N. seriolae, highlighting a potential risk factor in diseases outbreaks.