文献类型：期刊文献

英文题名：Characterization of Edwardsiella tarda waaL: roles in lipopolysaccharide biosynthesis, stress adaptation, and virulence toward fish

作者：Xu, Lili[1];Wang, Qiyao[1];Xiao, Jingfan[1];Liu, Qin[1];Wang, Xin[1];Chen, Tao[1];Zhang, Yuanxing[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2010

卷号：192

期号：12

起止页码：1039

外文期刊名：ARCHIVES OF MICROBIOLOGY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000284330600007)】；

基金：This work was supported by grants from the National High Technology Research and Development Program of China (2008AA092501), Ministry of Agriculture of China (Nos. nyhyzx07-046 and nycytx-50), as well as the National Special Fund for State Key Laboratory of Bioreactor Engineering (No. 2060204).

语种：英文

外文关键词：Edwardsiella tarda; WaaL; Lipopolysaccharide; Stress adaption; Virulence

摘要：Edwardsiella tarda is the causative agent of edwardsiellosis in fish. The genome sequence of a virulent strain EIB202 has been determined. According to the genome sequence, the lipopolysaccharide (LPS) synthesis cluster containing a putative O-antigen ligase gene waaL was identified. Here, the in-frame deletion mutant Delta waaL was constructed to analyze the function of WaaL in E. tarda EIB202. The Delta waaL mutant displayed absence in O-antigen side chains in the LPS production. The Delta waaL mutant exhibited an increased sensitivity to hydrogen peroxide indicating that the LPS was involved in the endurance to the oxidative stress in hosts during infection. In addition, the resistance of Delta waaL to serum and polymyxin B decreased remarkably. The Delta waaL mutant was also attenuated in virulence, showed an impaired ability in internalization of epithelioma papulosum cyprinid (EPC) cells and a comparatively poor ability of proliferation in vivo, which was in line with the increased LD50 value. These results indicated that waaL gene was a functional member of the gene cluster involved in LPS synthesis and highlighted the importance of the O-antigen side chains to stress adaption and virulence in E. tarda, signifying the gene as a potential target for live attenuated vaccine against this bacterium.