Development of a Memory Selection Device for Engineering Bacteria

Samantha Liang : Bioengineering

Mentor: Professor J. Christopher Anderson, Bioengineering

In order for synthetic biology to overcome the limitations of using only naturally-derived biological activities, tools for developing and identifying engineered genetic components with desired biochemical, enzymatic, or regulatory properties are greatly needed. Samantha is building a genetic threshold-gated memory selection circuit incorporating positive/negative selections and an irreversible Cre recombinase excision circuit in the E.coli genome. With this device, bacteria will exist in one of two mutually exclusive antibiotic-resistant states depending on whether or not they exhibit a desired activity, and Cre recombinase expression will serve as the switch between the positive and negative states. Linking desired activities to Cre expression will allow for efficient selection of new promoters and proteins, making this genetic selection device a valuable foundational technology with a wide variety of applications in genetic engineering.