AI-2对鸭疫里氏杆菌粘附入侵Vero细胞及其相关基因转录水平的影响

Effect of autoinducer 2on Riemerella antatipestifer adherence and invasion to Vero cells

摘要:

摘要:【目的】自诱导信号分子AI-2(Autoinducer-2，AI-2)作为细菌间的通用自诱导信号分子，参与细菌众多生理功能的调控。本研究通过开展AI-2在鸭疫里氏杆菌(Riemerella antatipestifer，RA)CH3 株对非洲绿猴肾细胞(Vero 细胞)的粘附、入侵以及对RA 相关基因调控作用的研究，为进一步研究AI-2对RA的调控作用奠定基础。【方法】在CH3(血清型1 型)对Vero细胞的粘附、入侵过程中加入不同浓度的AI-2，研究其对CH3 粘附、入侵Vero的影响;在添加184.0μmol/L AI-2的胰蛋白胨大豆肉汤(TSB)中培养RA CH3菌株，利用real-time PCR来检测AI-2对RA相关基因转录水平的影响。【结果】结果表明，AI-2浓度为18.4μmol/L时，AI-2对CH3粘附Vero细胞的抑制性最强，为62%，当AI-2浓度为184.0 μmol/L时，AI-2对CH3入侵Vero细胞的促进性最强为194%。荧光定量PCR结果表明AI-2对部分基因的转录有促进作用，对部分基因的转录有抑制作用。【结论】AI-2参与调控RA 粘附、入侵Vero细胞及RA毒力因子、免疫原性蛋白基因以及代谢相关基因转录水平的调控。

Abstract:

Abstract:［Objective］ Autoinducer 2 (AI-2)，used to communicate among bacterial species，regulates numerous physiological functions of bacteria． In this study，we studied the effect of AI-2 on adherence and invasion of Riemerella antatipestifer (RA) strain CH3 to Vero cells and transcriptional levels of virulence-related and metabolism-related genes were investigated．［Methods］To verify whether the adherence and invasion of CH3 was affected by AI-2，we added different concentrations of AI-2 to the cocultures of Vero cells and CH3 and then calculated adherence percentages and invasion percentages of tested groups．We further added AI-2 (184.0μmol/L) to the tryptone soya broth culture of CH3 and then detected the effect of transcriptional levels of related genes of CH3 using real-time PCR．［Results］The adherence of CH3 to Vero cells was decreased most to 62% with 18. 4μmol/L AI-2 and the invasion of CH3 to Vero cells was increased most to 194% with 184.0μmol/L AI-2．The result of real-time PCR shows that AI-2 increased transcriptional levels of some virulence-related genes and decreased transcriptional levels of some metabolism-related genes．［Conclusion］These results suggest that AI-2 affected adherence and invasion of CH3 to Vero cells．Moreover，AI-2 could regulate some genes of CH3 to modulate particular physiological behaviors．