文献类型：期刊文献

英文题名：Characterization of Edwardsiella tarda rpoS: Effect on serum resistance, chondroitinase activity, biofilm formation, and autoinducer synthetases expression

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

机构：[1] State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China

年份：2009

卷号：83

期号：1

起止页码：151

外文期刊名：Applied Microbiology and Biotechnology

收录：EI(收录号：20091812067442)

语种：英文

外文关键词：Biofilms - Body fluids - Gene expression

摘要：In this study, rpoS gene was identified from Edwardsiella tarda EIB202 and its functional role was analyzed by using an in-frame deletion mutant δrpoS and the complemental strain rpoS +. Compared with the wild type and rpoS +, δrpoS was impaired in terms of the ability to survive under oxidative stress and nutrient starvation, as well as the resistance to 50% serum of Scophthalmus maximus in 3 h, demonstrating essential roles of RpoS in stress adaptation. The rpoS mutant also displayed markedly increased chondroitinase activity and biofilm formation. Real-time polymerase chain reaction revealed that the expression level of quorum sensing autoinducer synthetase genes luxS and edwI was increased by 3.7- and 2.5-fold in the rpoS mutant strain. Those results suggested that rpoS might be involved in the negative or positive regulation of chondroitinase and biofilm formation, or quorum sensing networks in E. tarda, respectively. Although there were no obvious differences between the wild-type and the rpoS mutant in adherence of epithelioma papulosum cyprini (EPC) cell and in the lethality on fish model, rpoS deletion leads to the drastically reduced capacity for E. tarda to internalize in EPC cells, indicating that RpoS was, while not the main, the factor required for the virulence network of E. tarda. ? 2009 Springer-Verlag.