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<h3>Project description</h3> | <h3>Project description</h3> | ||
<p> | <p> | ||
− | We are planning to use dCas9 and asRNA to silence the production of toxins A and B in <i>C. difficile</i> | + | We are planning to use dCas9 and asRNA to silence the production of toxins A and B in <i>C. difficile</i> which is known for causing hospital-acquired diarrhoea in the Western world. We want to prove a concept of asRNA and/or dCas9 as an alternative to antibiotic treatment against <i>C.difficile</i>. As a result, we will neutralise the negative impacts of bacteria on human health rather than completely killing it. |
We will create and test a promoter library in both <i>E. coli</i> and <i>C. difficile</i>, express anti-sense RNAs in <i>C. difficile</i>, express dCas9/sgRNA in <i>E. coli</i> and <i>C. difficile</i>. dCas9 is planned to be used to repress the reporter gene <i>gusA</i>, by dCas9 binding to the toxin promoters placed upstream of <i>gusA</i>, in <i>E. coli</i> and <i>C. difficile</i>. If this repression is successful the system will be used to repress the <i>C. difficile</i> toxin genes. | We will create and test a promoter library in both <i>E. coli</i> and <i>C. difficile</i>, express anti-sense RNAs in <i>C. difficile</i>, express dCas9/sgRNA in <i>E. coli</i> and <i>C. difficile</i>. dCas9 is planned to be used to repress the reporter gene <i>gusA</i>, by dCas9 binding to the toxin promoters placed upstream of <i>gusA</i>, in <i>E. coli</i> and <i>C. difficile</i>. If this repression is successful the system will be used to repress the <i>C. difficile</i> toxin genes. | ||
</p> | </p> | ||
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<div class="ui bulleted list"> | <div class="ui bulleted list"> | ||
<div class="item">E.coli DH5 alpha, E. coli sexpress (NEB express + R702)</div> | <div class="item">E.coli DH5 alpha, E. coli sexpress (NEB express + R702)</div> | ||
− | <div class="item">C.difficile | + | <div class="item"><i>C.difficile</i> SBRC 078 (clinical isolate), <i>C.difficile</i> bacteriophage phiSBRC</div> |
</div> | </div> | ||
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<div class="ui red message"> | <div class="ui red message"> | ||
<h3 class="ui small header">Risks the organisms pose</h3> | <h3 class="ui small header">Risks the organisms pose</h3> | ||
− | E.coli is the model lab organism and has low, but not non-existent, virulence. It is very unlikely to cause disease in healthy adults. The risk group mostly includes young, elderly, immunocompromised people and is spread through injection or contamination of broken skin with bacteria which can cause inflammation. The release of bacteria in the environment poses the risk of spreading of antibiotics resistance. By following appropriate laboratory safety precautions and waste disposal regulations, we can minimise unsafe exposure to the bacteria and prevent release into the environment. | + | <i>E. coli</i> is the model lab organism and has low, but not non-existent, virulence. It is very unlikely to cause disease in healthy adults. The risk group mostly includes young, elderly, immunocompromised people and is spread through injection or contamination of broken skin with bacteria which can cause inflammation. The release of bacteria in the environment poses the risk of spreading of antibiotics resistance. By following appropriate laboratory safety precautions and waste disposal regulations, we can minimise unsafe exposure to the bacteria and prevent release into the environment. |
</div> | </div> | ||
<div class="ui divider"></div> | <div class="ui divider"></div> | ||
− | <h3>Species used as a | + | <h3>Species used as a chassis</h3> |
<div class="ui bulleted list"> | <div class="ui bulleted list"> | ||
<div class="item">E.coli DH5 alpha, E. coli sexpress (NEB express + R702)</div> | <div class="item">E.coli DH5 alpha, E. coli sexpress (NEB express + R702)</div> | ||
− | <div class="item"> | + | <div class="item"><i>C.difficile</i> SBRC 078 (clinical isolate)</div> |
</div> | </div> | ||
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<div class="ui red message"> | <div class="ui red message"> | ||
<h3 class="ui small header"> | <h3 class="ui small header"> | ||
− | Risks the | + | Risks the chassis species pose |
</h3> | </h3> | ||
<p> | <p> | ||
− | The SBRC have risk assessments and waste disposal management that will ensure that chassis are not released into the environment as they possess antibiotic resistance that could be spread to other bacteria. Except that, E.coli strains used do not possess pathogenic properties and therefore pose minimal to no risk to human health. | + | The SBRC have risk assessments and waste disposal management that will ensure that chassis are not released into the environment as they possess antibiotic resistance that could be spread to other bacteria. Except that, <i>E. coli</i> strains used do not possess pathogenic properties and therefore pose minimal to no risk to human health. |
<br><br> | <br><br> | ||
− | C. difficile could pose a risk to human health in immunocompromised patients or patients receiving antibiotic therapy. However, they would need to ingest spores, which can be removed with hand washing. Colleagues or team members are not authorised to enter the lab whilst on antibiotic therapy. Providing correct PPE is worn and hand washing procedures are followed, C. difficile will not pose a risk to the lab-based team members. Release of C.difficile into environment could cause a hazard due to production of spores that can survive in the environment for a long time. The lab follows specific disposal rules for C.difficile specifically. | + | <i>C.difficile</i> could pose a risk to human health in immunocompromised patients or patients receiving antibiotic therapy. However, they would need to ingest spores, which can be removed with hand washing. Colleagues or team members are not authorised to enter the lab whilst on antibiotic therapy. Providing correct PPE is worn and hand washing procedures are followed, <i>C.difficile</i> will not pose a risk to the lab-based team members. Release of <i>C.difficile</i> into environment could cause a hazard due to production of spores that can survive in the environment for a long time. The lab follows specific disposal rules for <i>C.difficile</i>SBRC 078 specifically. |
</p> | </p> | ||
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E.coli sexpress (NEB express +R702) is a new strain created at SBRC Nottingham and the research paper on it has not been published yet. | E.coli sexpress (NEB express +R702) is a new strain created at SBRC Nottingham and the research paper on it has not been published yet. | ||
− | + | <i>C.difficile</i>SBRC 078 is a clinical isolate of <i>C.difficile</i> belonging to PCR ribotype 078. | |
</div> | </div> | ||
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<h3>Experiments undertaken with organisms and parts</h3> | <h3>Experiments undertaken with organisms and parts</h3> | ||
<p> | <p> | ||
− | All parts will be used to create and test a promoter library in both E. coli and C. difficile, express asRNAs in C. difficile | + | All parts will be used to create and test a promoter library in both <i>E. coli</i> and <i>C.difficile</i>, express asRNAs in <i>C.difficile</i> express dCas9/sgRNA in <i>E. coli</i> and <i>C.difficile</i>. The asRNAs will be used to repress the expression of toxin A and B in <i>C.difficile</i>. dCas9 will be used to repress the reporter gene <i>gusA</i> (Cas9 binding to the toxin promoters placed upstream of <i>gusA</i>) in <i>E. coli</i> and <i>C.difficile</i>.If this repression is successful the system will be used to repress the <i>C.difficile</i> toxin genes. |
<br><br> | <br><br> | ||
− | If toxin supression in E.coli is successful, we plan to use E.coli sexpress (NEB express + R702) to conjugate E.coli containing asRNA or dCas9 vector into C.difficile | + | If toxin supression in <i>E. coli</i> is successful, we plan to use <i>E. coli</i> sexpress (NEB express + R702) to conjugate <i>E. coli</i> containing asRNA or dCas9 vector into <i>C.difficile</i> SBRC 078 to test toxin suppression in the host organism. Given enough time, we plan to insert asRNA/dCas9 system into <i>C.difficile</i> bacteriophage phiSBRC as an ultimate test of our project efficacy. |
</p> | </p> | ||
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<h3 class="ui small header">Risks that could arise from experiments</h3> | <h3 class="ui small header">Risks that could arise from experiments</h3> | ||
<p> | <p> | ||
− | In our project we use all the basic microbiology techniques and equipment which may possess risks of causing disease after long exposure or physical injuries. To ensure safety of all lab-based team members, specific training for each technique was given with all safety precautions explained. All team members could use | + | In our project we use all the basic microbiology techniques and equipment which may possess risks of causing disease after long exposure or physical injuries. To ensure safety of all lab-based team members, specific training for each technique was given with all safety precautions explained. All team members could use Bunsen burner without burning themselves or others; bench centrifuges were handled properly due to aerosols production; SYBR Safe was handled in the designated area to minimise carcinogenic-related risks; sharp equipment was handled safely to prevent injuries, etc. |
Throughout the work in the lab, all team members wore PPE at all times, with extra precautions taken when working in the lab. | Throughout the work in the lab, all team members wore PPE at all times, with extra precautions taken when working in the lab. | ||
<br><br> | <br><br> | ||
The introduction of antibiotic-resistant genes into bacteria can pose a threat to risk groups if released. To minimise the risk and prevent the unwanted release, the safety protocols for handling and disposal of genetically-modified bacteria were followed at all times (e.g. putting waste in appropriate bins, autoclaving, washing hands after leaving the laboratory, etc). | The introduction of antibiotic-resistant genes into bacteria can pose a threat to risk groups if released. To minimise the risk and prevent the unwanted release, the safety protocols for handling and disposal of genetically-modified bacteria were followed at all times (e.g. putting waste in appropriate bins, autoclaving, washing hands after leaving the laboratory, etc). | ||
− | + | Working in biosafety level 2 anaerobic cabinet can be challenging for someone with not much experience due to relatively hot environment and continuous limitation of movement. To minimise the risk of sudden loss of consciousness or other extreme situations, at least one other person was present during work in the cabinet. This was applied to all our work in the lab - team members worked at least in pairs to ensure maximum safety during experimental procedures. At least one supervisor was present in the lab at all times during lab work. | |
When working with phage, it is important to follow strict safety regulations as inappropriate handling may cause risk to both the person who carries out experiment as well as other people around him/her. People working with bacteriophage received proper safety training and were introduced to all specific rules. | When working with phage, it is important to follow strict safety regulations as inappropriate handling may cause risk to both the person who carries out experiment as well as other people around him/her. People working with bacteriophage received proper safety training and were introduced to all specific rules. | ||
</p> | </p> | ||
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<h3 class="ui red small header">Risks associated with real use</h3> | <h3 class="ui red small header">Risks associated with real use</h3> | ||
<p> | <p> | ||
− | Our project is basically focused on proving the concept that one can use bacteriophage therapy against C.difficile. We wanted to explore alternative treatment options due to the increasing problem of antibiotic resistance. Of course, we do not claim in any way that our final product will be straight away ready for therapeutic use. In the best scenario, it would need to be tested in vivo in | + | Our project is basically focused on proving the concept that one can use bacteriophage therapy against <i>C.difficile</i>. We wanted to explore alternative treatment options due to the increasing problem of antibiotic resistance. Of course, we do not claim in any way that our final product will be straight away ready for therapeutic use. In the best scenario, it would need to be tested <i>in vivo</i> in pre-clinical studies and in clinical trials to assess their safety and test for any side effects. This would be done with ethical approval. Pharmacokinetic studies and biochemical experiments would be carried out to determine optimum conditions for use. |
<br><br> | <br><br> | ||
− | Our project is focused on using phage. Even though it is specific to C.difficile, its specificity may vary depending on different conditions. More research would be needed to investigate possible non-specific infection. | + | Our project is focused on using phage. Even though it is specific to <i>C.difficile</i>, its specificity may vary depending on different conditions. More research would be needed to investigate possible non-specific infection. |
</p> | </p> | ||
</div> | </div> | ||
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<h3>How experts have overseen our project to manage identified risk</h3> | <h3>How experts have overseen our project to manage identified risk</h3> | ||
<p> | <p> | ||
− | Michelle Kelly, one of the safety officers at the lab our team has been working in, carried out a full laboratory safety induction and introduced the risk assessments and standard operating procedures that are adhered to when working in a Category 2 laboratory. She has also set up training records for each team member which requires signing off by advisors when each lab skill has been efficiently performed. She has been working on C.difficile for more than 5 years and possesses deep knowledge into proper project design that ensures safety of the researcher. | + | Michelle Kelly, one of the safety officers at the lab our team has been working in, carried out a full laboratory safety induction and introduced the risk assessments and standard operating procedures that are adhered to when working in a Category 2 laboratory. She has also set up training records for each team member which requires signing off by advisors when each lab skill has been efficiently performed. She has been working on <i>C.difficile</i> for more than 5 years and possesses deep knowledge into proper project design that ensures safety of the researcher. |
<br><br> | <br><br> | ||
− | Nigel Minton (PI) has worked on C. difficile and Clostridia for over 20 years and has overseen the project development. Four other advisors who will also oversee the work that is completed, all of whom have worked on Clostridia for at least 3 years. These researchers will be responsible for ensuring SOPs and RAs are followed on a day to day basis. All parts of our project fall under university biosafety regulations as was checked by PI and safety officer. | + | Nigel Minton (PI) has worked on <i>C.difficile</i> and Clostridia for over 20 years and has overseen the project development. Four other advisors who will also oversee the work that is completed, all of whom have worked on Clostridia for at least 3 years. These researchers will be responsible for ensuring SOPs and RAs are followed on a day to day basis. All parts of our project fall under university biosafety regulations as was checked by PI and safety officer. |
</p><div class="ui divider"></div> | </p><div class="ui divider"></div> | ||
<h3>Rules and guidance cover that helped manage identified risks</h3> | <h3>Rules and guidance cover that helped manage identified risks</h3> | ||
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Each team member has completed a building safety induction and wet lab team members have completed a laboratory work induction. Each requires the successful passing of a quiz. Each lab team member has read and signed risk assessments for all of the work they will be completing and has a training record which has to be completed by a supervisor when training has been completed. | Each team member has completed a building safety induction and wet lab team members have completed a laboratory work induction. Each requires the successful passing of a quiz. Each lab team member has read and signed risk assessments for all of the work they will be completing and has a training record which has to be completed by a supervisor when training has been completed. | ||
<br><br> | <br><br> | ||
− | UK Regulations and their associated guidance are implemented, the University of | + | UK Regulations and their associated guidance are implemented, the University of Nottingham has defined appropriate standards for the growth, storage, disposal and transport of biological agents and genetically modified organisms within its premises. All these requirements are written down in the safety regulation forms. Our project was reviewed by the university safety committee to ensure that it follows the biosafety regulations of the laboratory we use. |
<br><br> | <br><br> | ||
All wet lab members were trained to work in group risk 2 laboratory and using the facilities. All regulations regarding waste disposal, equipment use and handling of dangerous chemicals were introduced by the safety officer. At least one supervisor was always present in the lab to ensure that the safety protocols are followed thoroughly. | All wet lab members were trained to work in group risk 2 laboratory and using the facilities. All regulations regarding waste disposal, equipment use and handling of dangerous chemicals were introduced by the safety officer. At least one supervisor was always present in the lab to ensure that the safety protocols are followed thoroughly. | ||
− | In addition to standard procedures for working within a category 2 laboratory due to the nature of C. difficile no member of the team can enter the lab when they are taking antibiotics. | + | In addition to standard procedures for working within a category 2 laboratory due to the nature of <i>C.difficile</i> no member of the team can enter the lab when they are taking antibiotics. |
</p> | </p> | ||
</div> | </div> | ||
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<h3>Resistance factors</h3> | <h3>Resistance factors</h3> | ||
<p> | <p> | ||
− | We have used resistance factors, and have thus submitted an | + | We have used resistance factors, and have thus submitted an iGEM check-in form. |
</p> | </p> | ||
<div class="ui divider"></div> | <div class="ui divider"></div> | ||
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<h3>Parts not on the whitelist</h3> | <h3>Parts not on the whitelist</h3> | ||
<p> | <p> | ||
− | We have used parts not on the whitelist, and have therefore submitted an | + | We have used parts not on the whitelist, and have therefore submitted an iGEM check-in form. |
</p> | </p> | ||
<div class="ui divider"></div> | <div class="ui divider"></div> |
Revision as of 09:20, 17 October 2018