The QseBC Quorum Sensing System is Involved in Salmonella enterica serovar Typhimurium Colonization of the Swine Gastrointestinal Tract

The response of bacteria to hormone-like, chemical molecules is termed quorum sensing, a mechanism for cell-to-cell communication that includes sensing the host environment. In the gastromtestinal tract, at least two quorum sensing molecules are present that activate the bacterial QseBC quorum sensing system. autoinducer-3 (AI-3) and norepinephrine (NE). Al-3 is produced by bacteria, whereas NE is produced by the host, often during stress. We have demonstrated that the motility of Salmonella enterica serovar Typhimurium is enhanced in the presence of NE and 10% pre-conditioned medium (AI-3) from the wild-type strain.