Abstract

Quorum Sensing in Vibrio and its Relevance to Bacterial Virulence

Huan Liu, Swaminath Srinivas, Xiaoxian He, Guoli Gong, Chunji Dai, Youjun Feng, Xuefeng Chen and Shihua Wang

Quorum sensing is a widespread system of cell to cell communication in bacteria that is stimulated in response to population density and relies on hormone-like chemical molecules to control gene expression. In mutualistic marine organisms like Vibrio, this system enables them to express certain processes, like virulence, only when its impact as a group would be maximized. An N-acylhomoserine lactone-dependent LuxI/R quorum sensing system has first been exemplified in Vibrio fischeri in the 1970s, regulating core bioluminescence genes. Since then, quorum sensing in Vibrio has been shown to influence a wide variety of process ranging from virulence factor formation to sporulation and motility. Most quorum sensing pathways produce and detect an autoinducer in a population dependent manner and transmit this information via a phospho-relay system to a core regulator that controls gene expression using certain pivotal elements. With several members of the genus Vibrio being known to cause severe foodborne infections, this review aims to present an overview of the quorum sensing systems present in four major Vibrio pathogens, V. fischeri, V. harveyi, V. cholerae and V. vulnificus and their roles in regulating the virulence of these organisms.