PennState/Lab/Notebooks

Our system is designed to produce Hemoglobin, Heme, and the necessary chaperones and detoxifying agents to promote the transport of oxygen throughout the bloodstream.  We also investigated alternates to hemoglobin and other strategies for its production.

Our bacterial chassis has been heavily modified to remove its sepsis-inducing toxicity, immunogenic factors, and ability to grow within the bloodstream, as well as promote its ability to last longer in the bloodstream by masking it from the immune system.

The Controller is an integrated genetic circuit comprised of two plasmids that allows stable maintenance of the system's various operons on a large single-copy plasmid in a dormant state. Upon induction, the copy number of the operons and their transcription increase 100-fold resulting in a dramatic increase in protein expression.

To prevent chance of infection or unwanted proliferation after hemoglobin production, we have engineered a genetic self-destruct mechanism whereby when induced, the bacterial cell will express a genetic material-degrading toxin which kills the cell, but leaves it physically intact.

To enable preservation of our bacteria for prolonged periods, we are including the ability to produce the compounds hydroxyectoine and trehalose that will enable our bacteria to survive freeze-drying intact.  This will dramatically increase shelf-life and decrease transport costs.