Berkeley UC
From 2007.igem.org
The necessity of inexpensive, disease free, and universally compatible blood substitutes is undisputed. There are currently no blood substitutes approved for use in the US or the UK, and whole blood is almost always in short supply. Developing countries have the greatest need for blood transfusions, however many lack the necessary donation and storage infrastructure and the required number of healthy donors. To address this problem, we are developing an innovative and cost-effective red blood cell substitute constructed from E. coli bacteria engineered to include the critical capabilities of human erythrocytes. Our bacterial system includes the controlled ability to carry oxygen with hemoglobin, safely exist in the bloodstream without chance of infection, and be stored for prolonged periods in a freeze-dried state.
Support for Berkeley iGEM 2007 was generously provided by SynBERC and The Camille and Henry Dreyfus Foundation, Inc.
The System's Components |
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Oxygen Carrying 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. |
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The Chassis 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. |
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The Controller 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. |
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Genetic Self-Destruct 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. |
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Freeze Drying To enable preservation of our bacteria for long time 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. |
Team Members |
Advisors John Dueber • Christopher Anderson • Adam Arkin • Jay Keasling Teaching Assistants Support Undergraduate Researchers High School Students |