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<h3>Safety</h3> | <h3>Safety</h3> | ||
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− | <p1> Our genetic circuit is activated/deactivated by the redox state of the transcription factor (SoxR). SoxR oxidation is modulated by small redox molecules, such as pyocyanin. However, after Dr. Francesca Ceroni, a PI at Imperial who was pregnant at the time declined to meet us in the lab out of concern of toxic substances, we realized that toxicity is a huge factor in downstream implementation of our system. Pyocyanin is a toxin synthesised by the pathogen Pseudomonas aeruginosa and is implicated in its virulence (https://www.sciencedirect.com/science/article/pii/S0924857912002105?via%3Dihub). We also realized that using another cheaper redox molecule could not only make our system cheaper to use, but also replace inducer molecules such as IPTG due to their price. Using PMS which is a small redox molecule, we can activate a gene much like IPTG would with p<i>lac</i>. Not only is PMS far cheaper than both pyocyanin and IPTG, it is also non-toxic and makes our system more applicable for real world applications. | + | <p1> Our genetic circuit is activated/deactivated by the redox state of the transcription factor (SoxR). SoxR oxidation is modulated by small redox molecules, such as pyocyanin. However, after Dr. Francesca Ceroni, a PI at Imperial who was pregnant at the time declined to meet us in the lab out of concern of toxic substances as well as <a href="https://2018.igem.org/Team:Imperial_College/Public_Engagement#opinion"><b>public concern</b></a> on the toxicity of our system, we realized that toxicity is a huge factor in downstream implementation of our system. Pyocyanin is a toxin synthesised by the pathogen Pseudomonas aeruginosa and is implicated in its virulence (https://www.sciencedirect.com/science/article/pii/S0924857912002105?via%3Dihub). We also realized that using another cheaper redox molecule could not only make our system cheaper to use, but also replace inducer molecules such as IPTG due to their price. Using PMS which is a small redox molecule, we can activate a gene much like IPTG would with p<i>lac</i>. Not only is PMS far cheaper than both pyocyanin and IPTG, it is also non-toxic and makes our system more applicable for real world applications. |
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<h4>Toxicity comparison between Pyocyanin and PMS</h4></br> | <h4>Toxicity comparison between Pyocyanin and PMS</h4></br> |
Revision as of 03:03, 16 October 2018
Integrated HP
Summary of Integrated Human Practices
Safety
Toxicity comparison between Pyocyanin and PMS
The 2012 OSHA Hazard Communication Standard ranks hazard ratings with the use of categories, with Category 0 being the lowest risk and Category 4 being the highest. With regards to toxicity, pyocyanin is a Category 4 substance and extreme care was taken during our wet lab to ensure our own safety and any contact with pyocyanin would warrant immediate medical attention, PMS on the other hand is a Category 0 substance and thus is far easier and safer to handle. OSHA pages on PMS (http://datasheets.scbt.com/sc-215700.pdf): OSHA pages on Pyocyanin (http://datasheets.scbt.com/sds/aghs/en/sc-205475.pdf).Cost comparison between PMS and common inducer molecules
A cursory look at the costs of PMS, pyocyanin and common inducer molecules (such as IPTG) already reveal stark differences in costs per gram. When accounting for working concentrations, this difference is further magnified, with PMS being 268 or 2680 times cheaper than IPTG (depending on levels of IPTG used described by a NEB protocol provided here:https://www.neb.com/protocols/1/01/01/protein-expression-using-bl21de3-c2527) and 3584 times cheaper than pyocyanin. These costs are summarized in a table below. However costs only matter if it can be shown that PMS can have a similar fold induction to common inducer molecules such as IPTG and experimental results for fold induction suggesting that is the case can be found below. Placeholder for table Click here for experimental resultsEnvironment
Biocontainment
Placeholder for Biocontainment GIF(http://www.loc.gov/law/help/restrictions-on-gmos/eu.php)
. By controlling transcription of growth retardants or toxins, like gp2 and MazF respectively, we can control where our bacteria will live and thus add a layer of biocontainment. Click here for experimental results