Like many pathogens V. cholerae uses quorum sensing as part of the regulatory mechanism to control gene expression.

1. Like many pathogens V. cholerae uses quorum sensing as part of the regulatory mechanism to control gene expression. Why would a disease — causing bacterium use quorum sensing to control expression of toxins or other molecules that allow the organism to cause disease. 2. Unlike most pathogens that respond to high population density by turning on high population density by turning on genes that allow them to cause disease, V. cholerae cells in dense population turn off the genes associated with attachment and toxin productions. As those genes are turned off, the cells turn on genes required for biofilm productions. How might this benefit the organism? 3. How could a better understanding of the signaling molecules involved in quorum sensing lead to new methods to control pathogens. 4. Researchers are investigating using quorum sensing signaling molecules of other bacteria to increase the success rate of V. cholerae isolation from environmental samples. Why might these molecules induce V. cholerae to exit the dormant state?