Sensing of the Microbial Neighborhood by Candida albicans

Candida albicans is a polymorphic fungus that inhabits a variety of niches in healthy human bodies. In addition to being a component of the normal microbiota, C. albicans is an opportunistic pathogen that causes superficial mucosal infections as well as disseminated disease. Importantly, C. albicans that is part of the normal microbiota is responsible for seeding these infections As the fourth most common cause of nosocomial infections, C. albicans is commonly isolated from immunocompromised individuals, including those with HIV, those immunosuppressed due to cancer treatment, and premature babies The ability of this fungus to present as both as a commensal and as a life-threatening pathogen is due, in large part, to its ability to sense and react to the environment. C. albicans uses quorum sensing to react to other Candida cells, pheromone signaling in the context of mating and sexual biofilm formation, and a variety of mechanisms for interkingdom interactions with the bacterial microbiota. This article highlights the ways in which C. albicans cells signal both to one another and to other microbial species.