Non-coding small RNAs in the Vibrio cholerae quorum sensing system control the expression of important genes for associations in the environment and in the human host

Introduction Bacteria produce and then respond to signal molecules termed autoinducers (AI) in a process of cell-cell communication called quorum sensing (QS). Extracellular AI levels increase with increasing cell density, so AI detection allows bacteria to monitor their population numbers. When AIs reach a critical concentration, the bacteria in the group synchronize their gene expression to orchestrate behaviors, such as virulence, biofilm formation, and DNA uptake, which are more productive for bacterial groups than individuals (Ng and Bassler 2009).