Team:UCSF

This year, the UCSF iGEM team will research how to develop artificial biofilms via yeast cell surface display. Our team will be working with the non-pathogenic yeast strain S. Cerevisiae. Our goal is to be able to control the forming of biofilms by the yeast cells.

Biofilms form on the inside of water pipes, medical supplies, and even human tissues. They are dangerous, because they are especially resistant to antibiotics and provide shelter for microbes that are even more dangerous. We hope to form synthetic biofilms and then test out ways to destroy them.

First, we want to synthetically engineer S. cerevisiae to form biofilms that we can control by having yeast display adhesive proteins on its surface . We are using a yeast surface display system that takes advantage of natural yeast mating receptors. We are trying to display adhesive proteins from other species of yeast, mouse, fungus, and corn. We hope that by having yeast express more adhesive proteins it would form biofilms more readily. This synthetic biofilm can be used as a model for more dangerous biofilms.

With this form of easier to control and form biofilm, we want to test out ways to destroy biofilms. We have three approaches that will disperse the biofilm, making it susceptible to antibiotics: 1) Our yeast can secrete enzymes that cut adhesins that hold the biofilm together. 2) We can use the synthetic gene silencing system designed by the 2008 UCSF iGEM team. 3) We can take advantage of the mating receptor as a channel to move biofilm-destroying substances from our engineered yeast into natural yeast biofilms.