This project uses the medically important dimorphic fungus Candida albicans to study general mechanisms of shape determination in fungi. It extends the bacterial concept of quorum sensing to more complicated organisms such as the fungi. The project explores how single celled fungi determine how many of their kind are present at a certain location. That is, are enough cells present to have achieved a threshold or quorum? For Candida albicans, the consequences of quorum sensing are that the fungi exhibit different growth patterns depending solely on their initial cell densities; they grow as single celled, budding yeasts at high cell densities and as long filaments at low cell densities. Each cell releases low levels of a specific signaling molecule and then senses the extracellular concentration of that molecule. This project focuses on whether quorum sensing is a general phenomenon in all dimorphic fungi and aims to elucidate the chemical structures of the molecules which are secreted and detected. The long term benefits from this project could include the development of novel anti-fungal drugs, designed not to kill the fungus but instead to restrict its growth to the yeast morphology. There is a dire need of effective anti-fungal antibiotics and a novel class of anti-fungal drugs would greatly benefit the treatment of both animal and plant diseases.
