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<h3>Summary of Integrated Human Practices</h3> | <h3>Summary of Integrated Human Practices</h3> | ||
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− | <p1> | + | <p1>We engaged in direct dialogue with stakeholders, as per the <b><a href="https://2018.igem.org/Team:Imperial_College/scicomm">Communication Strategies Guide (CSG)</a></b>. This approach allowed us to devise potential applications for our system, as well as correct design flaws such as the use of toxic pyocyanin as a redox-cycling molecule. This led us to re-design our system with a safer molecule (phenazine methosulfate -PMS-), which we demonstrated to be a remarkably cheap and effective inducer molecule, even when compared with broadly used inducers. We also identified that internal friction in teams is a common issue as proven to us by our experience as well as a survey that we conducted amongst 67 iGEM members from 14 other teams. To address this issue we developed our <a href="https://2018.igem.org/Team:Imperial_College/ltat"><b>team communication app (LTAT)</b></a> to help improve team communication both internally and within other teams. </p1> |
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<div id="safety"></div> | <div id="safety"></div> | ||
− | <h3> | + | <h3>Making our technology safer</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 | + | <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 over toxic substances, and in response to <a href="https://2018.igem.org/Team:Imperial_College/Public_Engagement#opinion"><b>public concern</b></a> that we identified over the toxicity of our system, we realized that toxicity is a huge issue with downstream implementation of our system. Pyocyanin is a toxin synthesised by the pathogen Pseudomonas <i>aeruginosa</i> and is implicated in its virulence <a href="https://www.sciencedirect.com/science/article/pii/S0924857912002105?via%3Dihub" class="highlight" target="_blank">(Ho Sui et. al., 2012).</a> 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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<div class="center"><img src="https://static.igem.org/mediawiki/2018/5/50/T--Imperial_College--IHP11.png"></div> | <div class="center"><img src="https://static.igem.org/mediawiki/2018/5/50/T--Imperial_College--IHP11.png"></div> |
Revision as of 22:41, 17 October 2018
Integrated HP
Summary of Integrated Human Practices
Making our technology safer
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 (Santa Cruz Biotechnology, 2010) 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 (Santa Cruz Biotechnology, 2017) and thus is far easier and safer to handle.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 407 times cheaper than IPTG and 6600 times cheaper than pyocyanin. These costs are summarized in a table below, where costs per gram are obtained using the lowest price per gram on Sigma-Aldrich. 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.Inducer | Working Concentrations | Price per gram (£) | Mass per liter of media (mg) | Price per liter of media (pence) | CAS No. | Relative price to PMS (%) | References |
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PMS | 0.2 uM | 15.76 | 0.0613 | 0.0966 | 299-11-6 | 100 | Experimental Data |
Pyocyanin | 2.5 uM | 12,120 | 0.526 | 638 | 85-66-5 | 660,000 | Experimental Data |
IPTG | 40 uM | 41.2 | 9.53 | 39.3 | 367-93-1 | 40,700 | (NEB, 2018) |
Arabinose | 6.66 M | 0.785 | 1000 | 78.5 | 5328-37-0 | 81,300 | (Spadiut et. al., 2010) |
aTc | 0.214 uM | 1650 | 0.0991 | 16.4 | 13803-65-1 | 17,000 | (Nallamsetty and Waugh, 2007) |