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

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．