Difference between revisions of "Team:RDFZ-China/Safety"

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             <h1> About Our Chassis </h1>
 
             <h1> About Our Chassis </h1>
 
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             <hr class= "line">
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             <p>Our project uses Bacillus subtilis 168. strain as the major chassis for the expression of sfp, yerP and LmrA. This strain is classified into Biosafety Level 1[1] based on the standards made by USA Center for Disease Control and Prevention. Therefore, we can use the chassis with relative ease, since the strain is non-pathogenic for healthy individuals and it poses minimal potential hazard to our lab members and the lab environment. But we still have to follow the biosafety precautions in our school lab.</p>
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             <p>Our project uses Bacillus subtilis 168. strain as the major chassis for the expression of sfp, yerP, and LmrA. This strain is classified as Biosafety Level 1[1] based on the standards made by USA Center for Disease Control and Prevention. Therefore, we can use the chassis with relative ease, since the strain is non-pathogenic for healthy individuals and it poses a minimal potential hazard to our lab members and the lab environment. But we still have to follow the biosafety precautions in our school lab.</p>
 
             <h1> Multidrug Resistance Factor LmrA </h1>
 
             <h1> Multidrug Resistance Factor LmrA </h1>
 
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             <p>LmrA is a ABC transporter responsible for multidrug resistance in Lactotococcus lactis. It can actively efflux a wide spectrum of clinically relevant antitumor, antimicrobial, antiviral drugs[2], including anthracyclines, vinca alkaloids, aminoglycosides, lincosamides, macrolides, quinolones, streptogramins, tetracyclines, chloramphenicol and novobiocin with energy provided by cellular ATP. Studies on heterologous expression of lmrA in Escherichia coli. has raised our awareness of potential biosafety issues. Transformation of the hypersensitive Escherichia coli strain CS1562 by a LmrA encoding plasmid has resulted in an increased resistance to 17 out of 21 clinically most used antibiotics[3], which is a significant result suggesting that such wild spectrum resistance is probable to be observed again in Bacillus subtilis, a Gram positive bacteria like Lactotococcus lactis, while Escherichia coli. is Gram negative. To reduce the risk as much as we can, we deliberately ordered LmrA coding sequence, without regulatory elements,  to be synthesized by IDT and tried to assemble the operon afterward in one step to avoid unexpected expression of LmrA in E. coli. strain DH5a. Therefore, we have proposed a plan using a kill-switch regulated by the absence of crude-oil related hydrocarbons in our chassis so that the potential problem of unwanted resistance may be avoided if we use LmrA instead of endogenous YerP for surfactin efflux. </p>
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             <p>LmrA is an ABC transporter responsible for multidrug resistance in Lactococcus lactis. It can actively efflux a wide spectrum of clinically relevant antitumor, antimicrobial, antiviral drugs[2], including anthracyclines, vinca alkaloids, aminoglycosides, lincosamides, macrolides, quinolones, streptogramins, tetracyclines, chloramphenicol and novobiocin with energy provided by cellular ATP. Studies on the heterologous expression of lmrA in Escherichia coli. has raised our awareness of potential biosafety issues. Transformation of the hypersensitive Escherichia coli strain CS1562 by a LmrA encoding plasmid has resulted in an increased resistance to 17 out of 21 clinically most used antibiotics[3], which is a significant result suggesting that such wild spectrum resistance is probable to be observed again in Bacillus subtilis, a Gram-positive bacteria like Lactococcus lactis, while Escherichia coli. is Gram-negative. To reduce the risk as much as we can, we deliberately ordered LmrA coding sequence, without regulatory elements,  to be synthesized by IDT and tried to assemble the operon afterward in one step to avoid the unexpected expression of LmrA in E. coli. strain DH5a. Therefore, we have proposed a plan using a kill-switch regulated by the absence of crude-oil related hydrocarbons in our chassis so that the potential problem of unwanted resistance may be avoided if we use LmrA instead of endogenous YerP for surfactin efflux. </p>
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             <h1> Proof-of-Concept experiment </h1>
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             <h1> Proof-of-Concept Experiment </h1>
 
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            <h1>In our proof-of-concept experiment, we set out to verify a protocol for quantitatively determining the efficiency of oil elution by different volumes and concentrations of surfactant solutions. Having such a protocol will greatly expedite our further experiments on the effectiveness of surfactin producing bacteria by directly comparing the qualitative results generated from using pure commercial surfactant solutions and Bacillus subtilis cell suspension as eluents. To make our proof-of-concept experiment safer and greener, while retaining validity of conclusions, we chose edible oil and dish detergent as substituents for crude oil and chemical-pure surfactants.</h1>
 
             <h1> Lab Practice </h1>
 
             <h1> Lab Practice </h1>
 
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            <h1> References </h1>
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         </div>
 
         </div>
 
         </section>
 
         </section>

Revision as of 06:28, 29 October 2017

RDFZ-China

About Our Chassis

Our project uses Bacillus subtilis 168. strain as the major chassis for the expression of sfp, yerP, and LmrA. This strain is classified as Biosafety Level 1[1] based on the standards made by USA Center for Disease Control and Prevention. Therefore, we can use the chassis with relative ease, since the strain is non-pathogenic for healthy individuals and it poses a minimal potential hazard to our lab members and the lab environment. But we still have to follow the biosafety precautions in our school lab.

Multidrug Resistance Factor LmrA

LmrA is an ABC transporter responsible for multidrug resistance in Lactococcus lactis. It can actively efflux a wide spectrum of clinically relevant antitumor, antimicrobial, antiviral drugs[2], including anthracyclines, vinca alkaloids, aminoglycosides, lincosamides, macrolides, quinolones, streptogramins, tetracyclines, chloramphenicol and novobiocin with energy provided by cellular ATP. Studies on the heterologous expression of lmrA in Escherichia coli. has raised our awareness of potential biosafety issues. Transformation of the hypersensitive Escherichia coli strain CS1562 by a LmrA encoding plasmid has resulted in an increased resistance to 17 out of 21 clinically most used antibiotics[3], which is a significant result suggesting that such wild spectrum resistance is probable to be observed again in Bacillus subtilis, a Gram-positive bacteria like Lactococcus lactis, while Escherichia coli. is Gram-negative. To reduce the risk as much as we can, we deliberately ordered LmrA coding sequence, without regulatory elements, to be synthesized by IDT and tried to assemble the operon afterward in one step to avoid the unexpected expression of LmrA in E. coli. strain DH5a. Therefore, we have proposed a plan using a kill-switch regulated by the absence of crude-oil related hydrocarbons in our chassis so that the potential problem of unwanted resistance may be avoided if we use LmrA instead of endogenous YerP for surfactin efflux.

Proof-of-Concept Experiment

In our proof-of-concept experiment, we set out to verify a protocol for quantitatively determining the efficiency of oil elution by different volumes and concentrations of surfactant solutions. Having such a protocol will greatly expedite our further experiments on the effectiveness of surfactin producing bacteria by directly comparing the qualitative results generated from using pure commercial surfactant solutions and Bacillus subtilis cell suspension as eluents. To make our proof-of-concept experiment safer and greener, while retaining validity of conclusions, we chose edible oil and dish detergent as substituents for crude oil and chemical-pure surfactants.

Lab Practice

References

s