Determinacion de genes involucrados en la cascada de activación del sistema RcsCDB en Salmonella typhimurium

Abstract

The Rcs system consists of the sensor protein RcsC, the cognate response regulator RcsB, and the histidin-containing phosphotransfer protein RcsD, which serve as an intermediary in the phosphoryl transfer from RcsC to RcsB. This system controls the biosynthesis of the colanic acid and flagella, and virulence genes. Although the real signal that leads to activation of this system is unknown, numerous membrane stress conditions are known to induce the Rcs system. In order to determine the system signal, we studied the effect of different compounds that affect the membrane on activation cascade system, through the expression of reporter genes. As several two-component systems respond to acetyl phosphate, we investigated the effect of ack and pta mutations in the activation of Rcs because they lead to its accumulation. Due to that in different conditions the glucose modulates the system, we analyzed the effect of mutations in genes involved in the pathway of glucose-6-phosphate required for the formation of enterobacterial common antigen (ECA). Our results contribute to understanding the relationship between membrane stresses with the metabolism of glucose to the activation of RcsCDB system.