Difference between revisions of "Team:RDFZ-China/Human Practices"

Line 53: Line 53:
 
     }
 
     }
  
        .description li, .description p {
+
    .description li, .description p {
            color: #404040;
+
        color: #404040;
        }
+
    }
  
        .description h3 {
+
    .description h3 {
            font-family: 'Avenir';
+
        font-family:'Avenir';
            font-size: 23px;
+
        font-size:23px;
        }
+
    }
  
        .description p {
+
    .description p {
            text-indent: 25px !important;
+
        text-indent: 25px !important;
            font-family: Avenir !important;
+
        font-family: Avenir !important;
            font-size: 23px !important;
+
        font-size: 23px !important;
        }
+
    }
  
        .description #ref li {
+
    .description #ref li {
            font-style: italic;
+
        font-style: italic;
            font-size: x-small;
+
        font-size: x-small;
            color: black;
+
        color: black;
        }
+
    }
  
        .description table {
+
    .description table {
            margin-top: 20px;
+
        margin-top: 20px;
            margin-left: 20px;
+
        margin-left: 20px;
            margin-right: 20px;
+
        margin-right: 20px;
            border: thin solid black;
+
        border: thin solid black;
            caption-side: top;
+
        caption-side: top;
            border-spacing: 0px;
+
        border-spacing: 0px;
        }
+
    }
  
        .description td, .description th {
+
    .description td, .description th {
            border: thin dotted gray;
+
        border: thin dotted gray;
            padding: 5px;
+
        padding: 5px;
            background-color: aliceblue;
+
        background-color: aliceblue;
            font-weight: 200;
+
        font-weight: 200;
            line-height: 22px;
+
        line-height: 22px;
        }
+
    }
  
  
        .description #pricetable table {
+
    .description #pricetable table {
            text-align: center;
+
        text-align: center;
            margin-left: 200px;
+
        margin-left: 200px;
            width: 600px;
+
        width: 600px;
        }
+
    }
  
 
     .basic_description .description #price th {
 
     .basic_description .description #price th {
Line 111: Line 111:
 
     }
 
     }
  
        .insert p img {
+
    .insert p img {
            width: 1200px;
+
        width: 1200px;
            margin-left: -100px;
+
        margin-left: -100px;
        }
+
    }
 +
 
  
 
     /* 左侧列表 */
 
     /* 左侧列表 */
 
     .paper-sidenav {
 
     .paper-sidenav {
 
         position: fixed;
 
         position: fixed;
         left: 0.1em;
+
         right: 2em;
        top: 15em;
+
         text-align: right;
         text-align: left;
+
        width: 20em;
+
 
         font-family: Avenir;
 
         font-family: Avenir;
         background-color: rgba(8,8,8,0);
+
         background-color: #E1FFFF;
 +
        bottom: 2em;
 +
        display: none;
 +
        z-index: 10000;
 
     }
 
     }
  
        .paper-sidenav ul {
+
    .paper-sidenav ul {
            list-style-type: none;
+
        list-style-type: none;
            list-style: none;
+
        list-style: none;
            padding-inline-start: 0.5em;
+
        padding-inline-start: 0.5em;
            margin-left: 0px;
+
        margin-left: 0px;
        }
+
    }
  
            .paper-sidenav ul p {
+
    .paper-sidenav ul p {
                color: black;
+
        color: black;
                font-size: 1.6em !important;
+
        font-size: 1.6em !important;
                font-weight: 500;
+
        font-weight: 500;
            }
+
    }
  
            .paper-sidenav ul a:link {
+
    .paper-sidenav ul a:link {
                text-decoration: none;
+
        text-decoration: none;
                color: black;
+
        color: black;
            }
+
    }
  
            .paper-sidenav ul a:visited {
+
    .paper-sidenav ul a:visited {
                text-decoration: none;
+
        text-decoration: none;
                color: black;
+
        color: black;
            }
+
    }
  
            .paper-sidenav ul a:hover {
+
    .paper-sidenav ul a:hover {
                text-decoration: none;
+
        text-decoration: none;
                color: blue;
+
        color: blue;
                background-color: #f9f9f9;
+
        background-color: #f9f9f9;
                font-size: larger;
+
        font-size: larger;
            }
+
    }
  
            .paper-sidenav ul a:active {
+
    .paper-sidenav ul a:active {
                text-decoration: none;
+
        text-decoration: none;
                color: black;
+
        color: black;
            }
+
    }
  
 
     .description .topic-title {
 
     .description .topic-title {
 
         padding-top: 50px;
 
         padding-top: 50px;
 +
    }
 +
 +
    .reference {
 +
        width: 1000px;
 +
        margin-left: auto;
 +
        margin-right: auto;
 +
        font-family: Arial, Helvetica, sans-serif;
 +
        padding-bottom: 30px;
 
     }
 
     }
 
</style>
 
</style>
<body style="width:1263px; margin-left:auto;margin-right:auto;background-color:white">
+
<body style="width:1263px; margin-left:auto;margin-right:auto;background-color:white" onscroll="scrollEvent()">
 
     <div id="body">
 
     <div id="body">
 
         <!--default for floating navigation-->
 
         <!--default for floating navigation-->
         <div class="paper-sidenav">
+
         <div id="sidebar" class="paper-sidenav">
 
             <ul>
 
             <ul>
 
                 <li>
 
                 <li>
 
+
                    <ul>
                        <ul>
+
 
                         <li><a href="#section1">What are we facing?</a></li>
 
                         <li><a href="#section1">What are we facing?</a></li>
 
                         <li><a href="#section2">Predecessors</a></li>
 
                         <li><a href="#section2">Predecessors</a></li>
Line 182: Line 191:
 
                         <li><a href="#section7">DIY Bio and Biosafety</a></li>
 
                         <li><a href="#section7">DIY Bio and Biosafety</a></li>
 
                         <li><a href="#section8">Community and Future</a></li>
 
                         <li><a href="#section8">Community and Future</a></li>
 +
                        <li><a href="#section9">References</a></li>
 
                     </ul>
 
                     </ul>
 
                 </li>
 
                 </li>
                <!-- <li>
 
                    <p>About</p>
 
                    <ul>
 
                        <li><a href="#section9">About our project</a></li>
 
                    </ul>
 
                </li>
 
                <li>
 
                    <p>Reference</p>
 
                    <ul>
 
                        <li><a href="#section10">Reference</a></li>
 
                    </ul>
 
                </li> -->
 
 
             </ul>
 
             </ul>
 
         </div>
 
         </div>
Line 206: Line 204:
 
             <div class="topic-title" id="section1">
 
             <div class="topic-title" id="section1">
 
                 <h3>What are we facing?</h3>
 
                 <h3>What are we facing?</h3>
                 <p>Biosafety has always been the major concern to the public, to the companies and the researchers. Doubts and worries raised just as genetic technology was invented. With the rapidly growing of synthetic biology and iGEM community, more and more synthetic biology products are built with the widely distributed DNA toolkits or the inexpensive DNA synthesis service; we are facing unprecedented biosafety issue that unwanted leakage of synthetic biology products to the environment may cause an unexpected but definitely disastrous problem. </p>
+
                 <p>Biosafety has always been the major concern to the public, to the companies and the researchers. Doubts and worries raised just as genetic technology was invented. With the rapidly growing of synthetic biology and iGEM community, more and more synthetic biology products are built with the widely distributed DNA toolkits or the inexpensive DNA synthesis service(Synthetic and Will); we are facing unprecedented biosafety issue that unwanted leakage of synthetic biology products to the environment may cause an unexpected but definitely disastrous problem. </p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section2">
 
             <div class="topic-title" id="section2">
 
                 <h3>Predecessors</h3>
 
                 <h3>Predecessors</h3>
                 <p>For decades, researchers were striving to build biosafety devices through auxotrophy or external inducive kill switches[], holins and restriction enzymes are most commonly used. Most of the failures of the previous devices were caused by mutation and evolution of immune. </p>
+
                 <p>For decades, researchers were striving to build biosafety devices through auxotrophy or external inducive kill switches(Lee et al.), holins and restriction enzymes are most commonly used. Most of the failures of the previous devices were caused by mutation and evolution of immune(Moe-Behrens et al.) . </p>
                 <p>The two major threats of engineered microbes’ leakage are the possible Horizontal Gene Transfer which will lead to the spread of recombinant DNA to the entire ecosystem, or the engineered bacteria could contaminate or overrun the natural habitat.[]</p>
+
                 <p>The two major threats of engineered microbes’ leakage are the possible Horizontal Gene Transfer which will lead to the spread of recombinant DNA to the entire ecosystem, or the engineered bacteria could contaminate or overrun the natural habitat.(Wright et al.)</p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section3">
 
             <div class="topic-title" id="section3">
                 <h2>Project Xscape</h2>
+
                 <h3>Project Xscape</h3>
 
                 <p>Under this circumstance, this year we decided to be a fundamentalist to synthetic biology, by using genetic circuits and logic gates, to establish biosafety devices which can apply to the real-world situation.</p>
 
                 <p>Under this circumstance, this year we decided to be a fundamentalist to synthetic biology, by using genetic circuits and logic gates, to establish biosafety devices which can apply to the real-world situation.</p>
 
                 <p>Since cell death and lysis mean there is a continual presence of free DNA in the environment, holins, which are most widely used are excluded from our choices, and colicin E2 nucleases (Darmstadt iGEM2016) came into our site. We choose site non-specific nucleases since the entire genome and plasmids needed to be entirely digested to prevent the spread, and we use nucleases from a different family to prevent the possible evolution of nuclease inhibitors. Artificial DNA, RNA, and amino acids are a good solution, but due to its high cost so far, it is not applicable to most of the user.</p>
 
                 <p>Since cell death and lysis mean there is a continual presence of free DNA in the environment, holins, which are most widely used are excluded from our choices, and colicin E2 nucleases (Darmstadt iGEM2016) came into our site. We choose site non-specific nucleases since the entire genome and plasmids needed to be entirely digested to prevent the spread, and we use nucleases from a different family to prevent the possible evolution of nuclease inhibitors. Artificial DNA, RNA, and amino acids are a good solution, but due to its high cost so far, it is not applicable to most of the user.</p>
Line 220: Line 218:
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section4">
 
             <div class="topic-title" id="section4">
                 <h2>For fermentation</h2>
+
                 <h3>For fermentation</h3>
                 <p>The first device we build is for the fermentation; we want to execute the escaped engineered bacteria from the fermenter, accidentally or intentionally. We used two environment factors to monitor the bacteria’s situation: temperature and population density, they are both high and tunable in the fermenter. So, the device will initiate when temperature and density are both low. We used thermal sensitive regulator (NUS iGEM2017) and quorum sensing regulator (MIT iGEM2004)as our sensor, sRNA and tetR family repressor PhlF(Glasgow iGEM2015) as the signal inverter. We add intergrase (Peking iGEM2017) controlled by the thermal sensitive regulator, which will turn the promoter of a lethal gene when temperature rise in the fermenter so that bacteria can survive at the very beginning. Also, we build a model to stimulate the minimum autoinducer required at the beginning of the fermentation[<a href="https://2018.igem.org/Team:RDFZ-China/Model" target=_blank>Modelling</a>], same as the purpose of integrase. This model is for keeping bacteria alive at the very beginning of fermentation. Together they form a NOR gate which will lead to cell death through genome degradation when temperature and density decrease.</p>
+
                 <p>The first device we build is for the fermentation; we want to execute the escaped engineered bacteria from the fermenter, accidentally or intentionally. We used two environment factors to monitor the bacteria’s situation: temperature and population density, they are both high and tunable in the fermenter. So, the device will initiate when temperature and density are both low. We used thermal sensitive regulator (NUS iGEM2017)(Piraner et al.) and quorum sensing regulator (MIT iGEM2004) (Canton et al.)as our sensor, sRNA(Storz et al.) and tetR family repressor PhlF(Glasgow iGEM2015)(Stanton et al.) as the signal inverter. We add intergrase (Peking iGEM2017) controlled by the thermal sensitive regulator, which will turn the promoter of a lethal gene when temperature rise in the fermenter so that bacteria can survive at the very beginning. Also, we build a model to stimulate the minimum autoinducer required at the beginning of the fermentation, same as the purpose of integrase. This model is for keeping bacteria alive at the very beginning of fermentation. Together they form a NOR gate which will lead to cell death through genome degradation when temperature and density decrease.</p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section5">
 
             <div class="topic-title" id="section5">
                 <h2>For Therapy</h2>
+
                 <h3>For Therapy</h3>
                 <p>The second device we build is for therapeutic bacteria, the device can carry out noninvasive tracing through ultrasound imaging of the gas vesicle, release the drug (from SHSBNU 2017) controlled by a thermal sensitive regulator at nidus by ultrasound tissue heating, and heat to a higher temperature to release nuclease and kill the bacteria after it finishes its mission. </p>
+
                 <p>The second device we build is for therapeutic bacteria, the device can carry out noninvasive tracing through ultrasound imaging of the gas vesicle(Shapiro et al.), release the drug (from SHSBNU 2017) controlled by a thermal sensitive regulator at nidus by ultrasound tissue heating, and heat to a higher temperature to release nuclease and kill the bacteria after it finishes its mission. </p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section6">
 
             <div class="topic-title" id="section6">
                 <h2>For Metabolic Stress</h2>
+
                 <h3>For Metabolic Stress</h3>
                 <p>We applied capacity monitor [] to quantify the expression burden of all our systems, and to reduce the metabolic stress, we designed another device for fermentation which used a LuxR repressive promoter (Peking iGEM2011) and cold-regulated 5’UTR region (Ionis Paris 2017). This device only involves one transcriptional regulator, which will be less energy consuming. </p>
+
                 <p>We applied capacity monitor (Ceroni et al.) to quantify the expression burden of all our systems, and to reduce the metabolic stress, we designed another device for fermentation which used a LuxR repressive promoter (Peking iGEM2011) and cold-regulated 5’UTR region (Ionis Paris 2017). This device only involves one transcriptional regulator, which will be less energy consuming. </p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section7">
 
             <div class="topic-title" id="section7">
                 <h2>DIY bio and Biosafey</h2>
+
                 <h3>DIY bio and Biosafey</h3>
 
                 <p>Back to the growing and glowing synthetic biology community, despite the ones doing it on campus, more and more people are starting it at home, they call themselves Genehacker or DIY biologists. The lack of sufficient training and efficient surveillance will be a time bomb which we do know there will be a monstrous harmful bioproduct will be made someday in the future, and indeed, it will be a significant threat to the current biosafety basis. Recall our memory to iGEM2009, Peking surveyed DIY bio, almost ten years later, we conducted a similar DIY bio-survey again. We tried to order materials for molecular experiments, using the delivery address to our home, the result was quite shocking that we can buy almost everything for the molecular experiment, from the internet. Then, we went through relevant laws and regulations throughout the world, which we found out that there are no laws related to the credit certification and the address certification about the people who book the biology reagent. Most of the laws are about the quality certification and how they would serve the user after they bought this. We interviewed the Director of the center for disease control and prevention. He said that within his experiment with the disease caused by the Bacteria leak, environmental pollution, the vast impact had been caused. Our country has been making all effort which is the highest effort that we have made in the history. He said it is not easy to solve the problem with hard work, it needs the cooperation between all the countries. He made an example of 731 army during the second world war two, the outbreak of pathogens can cause significant social harm. We are still on our way to win the battle, but the effort still needs to be put in.</p>
 
                 <p>Back to the growing and glowing synthetic biology community, despite the ones doing it on campus, more and more people are starting it at home, they call themselves Genehacker or DIY biologists. The lack of sufficient training and efficient surveillance will be a time bomb which we do know there will be a monstrous harmful bioproduct will be made someday in the future, and indeed, it will be a significant threat to the current biosafety basis. Recall our memory to iGEM2009, Peking surveyed DIY bio, almost ten years later, we conducted a similar DIY bio-survey again. We tried to order materials for molecular experiments, using the delivery address to our home, the result was quite shocking that we can buy almost everything for the molecular experiment, from the internet. Then, we went through relevant laws and regulations throughout the world, which we found out that there are no laws related to the credit certification and the address certification about the people who book the biology reagent. Most of the laws are about the quality certification and how they would serve the user after they bought this. We interviewed the Director of the center for disease control and prevention. He said that within his experiment with the disease caused by the Bacteria leak, environmental pollution, the vast impact had been caused. Our country has been making all effort which is the highest effort that we have made in the history. He said it is not easy to solve the problem with hard work, it needs the cooperation between all the countries. He made an example of 731 army during the second world war two, the outbreak of pathogens can cause significant social harm. We are still on our way to win the battle, but the effort still needs to be put in.</p>
 
             </div>
 
             </div>
 
             <div class="topic-title" id="section8">
 
             <div class="topic-title" id="section8">
                 <h2>Community and Future</h2>
+
                 <h3>Community and Future</h3>
 
                 <p>Also, we hosted two major meeting in Beijing, a Biosafety Forum in October, we invited team leader who runs his high school lab, lab teacher from a university lab, and a former team member from Peking iGEM2009, who participated in that DIY bio investigation ten years ago.</p>
 
                 <p>Also, we hosted two major meeting in Beijing, a Biosafety Forum in October, we invited team leader who runs his high school lab, lab teacher from a university lab, and a former team member from Peking iGEM2009, who participated in that DIY bio investigation ten years ago.</p>
 
                 <p>We concluded that the development of DIY bio should be taken seriously, and the permanent way to solve it is through implanting Biosafety awareness into our academic culture. Also, as iGEMer, we should strive to be the considerable and responsible leaders in our community, to ensure the biosafety issue has been taken properly. Another meeting was with biology Olympians all around China, we discussed the future of biology community during the meeting, especially with more and more high school iGEM teams coming up in China, but lack of relevant instruction and education to the students. We came up with the idea of setting up a collaboration between school to share and overcome difficulties hand in hand. This kind of meeting will be continued after iGEM2018, since the community usually grows fast after every iGEM season. </p>
 
                 <p>We concluded that the development of DIY bio should be taken seriously, and the permanent way to solve it is through implanting Biosafety awareness into our academic culture. Also, as iGEMer, we should strive to be the considerable and responsible leaders in our community, to ensure the biosafety issue has been taken properly. Another meeting was with biology Olympians all around China, we discussed the future of biology community during the meeting, especially with more and more high school iGEM teams coming up in China, but lack of relevant instruction and education to the students. We came up with the idea of setting up a collaboration between school to share and overcome difficulties hand in hand. This kind of meeting will be continued after iGEM2018, since the community usually grows fast after every iGEM season. </p>
 
                 <p>Hopefully, years later, biosafety awareness and considerations can be seriously taken in communities, laboratory studies, and real-world applications.</p>
 
                 <p>Hopefully, years later, biosafety awareness and considerations can be seriously taken in communities, laboratory studies, and real-world applications.</p>
 
             </div>
 
             </div>
             <!-- <div class="insert">
+
             <br>
                 <p><img src="https://static.igem.org/mediawiki/2017/d/d6/Pdcomicexp1.png"></p>
+
            <br>
 +
         
 +
        </div>
 +
        <div class="reference">
 +
            <div class="topic-title" id="section9">
 +
                <h3>References</h3>
 +
                 <p>Canton, Barry, et al. “Refinement and Standardization of Synthetic Biological Parts and Devices.” Nature Biotechnology, vol. 26, no. 7, 2008, pp. 787–93, doi:10.1038/nbt1413.</p>
 +
                <p>Ceroni, Francesca, et al. “Quantifying Cellular Capacity Identifies Gene Expression Designs with Reduced Burden.” Nature Methods, vol. 12, no. 5, 2015, pp. 415–18, doi:10.1038/nmeth.3339.</p>
 +
                <p>Lee, Jeong Wook, et al. “Next-Generation Biocontainment Systems for Engineered Organisms.” Nature Chemical Biology, Springer US, 2018, p. 1, doi:10.1038/s41589-018-0056-x.</p>
 +
                <p>Moe-Behrens, Gerd H. G., et al. “Preparing Synthetic Biology for the World.” Frontiers in Microbiology, vol. 4, no. JAN, 2013, pp. 1–10, doi:10.3389/fmicb.2013.00005.</p>
 +
                <p>Piraner, Dan I., et al. “Tunable Thermal Bioswitches for in Vivo Control of Microbial Therapeutics.” Food, Pharmaceutical and Bioengineering Division 2017 - Core Programming Area at the 2017 AIChE Annual Meeting, vol. 2, no. November, Nature Publishing Group, 2017, pp. 695–702, doi:10.1038/nchembio.2233.</p>
 +
                <p>Shapiro, Mikhail G., et al. “Biogenic Gas Nanostructures as Ultrasonic Molecular Reporters.” Nature Nanotechnology, vol. 9, no. 4, Nature Publishing Group, 2014, pp. 311–16, doi:10.1038/nnano.2014.32.</p>
 +
                <p>Stanton, Brynne C., et al. “Genomic Mining of Prokaryotic Repressors for Orthogonal Logic Gates.” Nature Chemical Biology, vol. 10, no. 2, 2014, pp. 99–105, doi:10.1038/nchembio.1411.</p>
 +
                <p>Storz, Gisela, et al. “Regulation by Small RNAs in Bacteria: Expanding Frontiers.” Molecular Cell, vol. 43, no. 6, 2011, pp. 880–91, doi:10.1016/j.molcel.2011.08.022.</p>
 +
                <p>Synthetic, How, and Biology Will. “Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves.” Choice Reviews Online, 2013, doi:10.5860/CHOICE.50-3835.</p>
 +
                <p>Wright, Oliver, et al. “Building-in Biosafety for Synthetic Biology.” Microbiology (United Kingdom), vol. 159, no. PART7, 2013, pp. 1021–35, doi:10.1099/mic.0.066308-0.</p>
 
             </div>
 
             </div>
            <div class="topic-title" id="section9">
 
                <h3>About our project</h3>
 
                <br />
 
                <h4 id="insp">a) Inspiration</h4>
 
                <br />
 
                <p>Every year, iGEM competition motivates teams from all over the world to devise numerous great project, genetically engineered organisms are designed to serve in wide range of fields. However, when it comes to application, the regulation of gene expression is not the only rising issue, but also the resilience of these engineered organisms that we need to concern. For example, some team’s bacteria have to work in dessert with extremely low water content(<a href="https://2016.igem.org/Team:KAIT_Japan" title="Team: KAIT_Japan">.ref</a>), or when cell components are freeze dried on the test paper to make a paper based biosensor, the system must undergo severe dehydration for storage and transport, and this would probably hamper their effectiveness during work.(<a href="https://2016.igem.org/Team:Toronto" title="Team:Toronto">.ref</a>). Our investigationfor the 2016 iGEM projects showed that over 299 entries, x% engineered organisms are facing practical issues related with extreme working conditions or environmental stress. As a consequence, team SIAT-SCIE is focusing on how we can transform the resilience of tardigrades into the engineered organisms. Increasing their efficiency during work and gives them greater potential to be put into real practice. </p>
 
                <br />
 
                <div class="insert">
 
                    <p><img src="https://static.igem.org/mediawiki/2017/8/8c/Pdcomicexp2.png"></p>
 
                </div>
 
                <h4 id="whatr">b) What are we doing?</h4><br />
 
                <ol>
 
                    <li>Our first goal is to test whether TDPs can provide desiccation resistance for enzyme in vitro.</li>
 
                    <br />
 
                    <li>Secondly, we transfer our designed plasmid into DH5α and express TDP in vivo to see if it can confer desiccation resistance, by comparing the engineered strain with the E. coli that didn’t express the TDP gene. Hence a protection mechanism is developed, which can facilitate other iGEM teams engineered organisms to work efficiently. </li>
 
                    <br />
 
                    <li>During ametabolic state, the DNA repairing mechanism is halted and cells are vulnerable to mutagenic radiation. Hence our final goal is to ameliorate our protection system by expressing the protein Dsup, in providing resistance towards radiation for the engineered bacteria, as well as MnSOD, which protect against oxidative stress during desiccation process.</li>
 
                </ol>
 
  
            </div>
 
            <div class="topic-title" id="section10">
 
                <h5>Reference:</h5>
 
                <ol>
 
                    <li id="r1">Goldenberg JZ, Lytvyn L, Steurich J, Parkin P, Mahant S, Johnston BC. Probiotics for the prevention of pediatric antibiotic-associated diarrhea. Cochrane Database of Systematic Reviews 2015, Issue 12. Art. No.: CD004827. DOI: 10.1002/14651858.CD004827.pub4</li>
 
                    <li id="r2">Friedrich Schiller University, Institute of Nutritional Science, Jena, German.Long-term consumption of fermented dairy products over 6 months increases HDL cholesterol. September 2002, Volume 56, Number 9, Pages 843-849</li>
 
                    <li id="r3">Broeckx, Ge ́raldine, Vandenheuvel, Dieter, Claes, Ingmar J.J., Lebeer, Sarah, Kiekens, Filip, Drying techniques of probiotic bacteria as an important step towards the development of novel pharmabiotics.International Journal of Pharmaceutics http://dx.doi.org/10.1016/j.ijpharm.2016.04.002 </li>
 
                    <li id="r4">Lievense, L.C., van‟t Riet, K., 1994. Convective drying of bacteria II. Factors influencing survival. Adv. Biochem. Eng. Biotechnol. 51, 71–89. doi:10.1007/BFb0008734 </li>
 
                    <li id="r5">Ghandi, A., Powell, I.B., Howes, T., Chen, X.D., Adhikari, B., 2012. Effect of shear rate and oxygen stresses on the survival of Lactococcus lactis during the atomization and drying stages of spray drying: A laboratory and pilot scale study. J. Food Eng. 113, 194–200. doi:10.1016/j.jfoodeng.2012.06.005 </li>
 
                    <li id="r6">Behboudi-Jobbehdar, S., Soukoulis, C., Yonekura, L., Fisk, I., 2013. Optimization of spray- drying process conditions for the production of maximally viable microencapsulated L. acidophilus NCIMB 701748. Dry. Technol. 31, 1274–1283. doi:10.1080/07373937.2013.788509</li>
 
                    <li id="r7">Poolman, B., 2002. Transporters and their roles in LAB cell physiology. Antonie van Leeuwenhoek, Int. J. Gen. Mol. Microbiol. 82, 147–164. doi:10.1023/A:1020658831293 </li>
 
                    <li id="r8">Santivarangkna, C., Kulozik, U., Foerst, P., 2008b. Inactivation mechanisms of lactic acid starter cultures preserved by drying processes. J. Appl. Microbiol. 105, 1–13. doi:10.1111/j.1365-2672.2008.03744.x </li>
 
                    <li id="r9">Garvey, C.J., Lenné, T., Koster, K.L., Kent, B., Bryant, G., 2013. Phospholipid membrane protection by sugar molecules during dehydration-insights into molecular mechanisms using scattering techniques. Int. J. Mol. Sci. 14, 8148–8163. doi:10.3390/ijms14048148</li>
 
                    <li id="r10">Bielecka, M., Majkowska, A., 2000. Effect of spray drying temperature of yoghurt on the survival of starter cultures, moisture content and sensoric properties of yoghurt powder. Nahrung 44, 257–260. doi:0027-769X/2000/0407-0257S17.50+.50/0 </li>
 
                    <li id="r11">Lebeer, S., Vanderleyden, J., De Keersmaecker, S.C.J., 2008. Genes and molecules of lactobacilli supporting probiotic action. Microbiol. Mol. Biol. Rev. 72, 728–764. doi:10.1128/MMBR.00017-08 </li>
 
                    <li id="r12">Jalali, M., Abedi, D., Varshosaz, J., Najjarzadeh, M., Mirlohi, M., Tavakoli, N., 2012. Stability evaluation of freeze-dried Lactobacillus tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules. Res. Pharm. Sci. 7, 31–36. </li>
 
                    <li id="r13">Jofré, A., Aymerich, T., Garriga, M., 2015. Impact of different cryoprotectants on the survival of freeze-dried Lactobacillus rhamnosus and Lactobacillus casei/paracasei during long- term storage. Benef. Microbes 6, 381–386. doi:10.3920/BM2014.0038 </li>
 
                    <li id="r14">Yamaguchi A, Tanaka S, Yamaguchi S, Kuwahara H, Takamura C, et al. (2012) Two Novel Heat-Soluble Protein Families Abundantly Expressed in an Anhydrobiotic Tardigrade. PLoS ONE 7(8): e44209. doi:10.1371/journal.pone.0044209 </li>
 
                    <li id="r15">Tunnacliffe A, Lapinski J, McGee B. (2005) A putative LEA protein, but no trehalose, is present in anhy- drobiotic bdelloid rotifers. Hydrobiologia 546: 315–321. </li>
 
                    <li id="r16">Hengherr S, Heyer AG, Kohler H-R, Schill RO. (2008) Trehalose and anhydrobiosis in tardigrades-evi- dence for divergence in responses to dehydration. FEBS J. 275: 281–288. PMID: 18070104</li>
 
                    <li id="r17">Zhang, Z.-Q. (2011). "Animal biodiversity: An introduction to higher-level classification and taxonomic richness" . Zootaxa. 3148: 7–12.</li>
 
                    <li id="r18">Rebecchi, L.; et al. "Two Tardigrade Species On Board the STS-134 Space Flight" in "International Symposium on Tardigrada, 23–26 July 2012" . p. 89. Retrieved 2013-01-14.</li>
 
                </ol>
 
            </div>-->
 
 
         </div>
 
         </div>
 
    </div>
 
 
</body>
 
</body>
 +
<script>
 +
function scrollEvent(){
 +
if(document.documentElement.scrollTop > 300) {
 +
  document.getElementById("sidebar").style.display="block";
 +
} else {
 +
  document.getElementById("sidebar").style.display="none";
 +
}
 +
}
 +
</script>
 
</html>
 
</html>
 
{{RDFZ-China/footer}}
 
{{RDFZ-China/footer}}

Revision as of 10:16, 17 October 2018

pdcomic

What are we facing?

Biosafety has always been the major concern to the public, to the companies and the researchers. Doubts and worries raised just as genetic technology was invented. With the rapidly growing of synthetic biology and iGEM community, more and more synthetic biology products are built with the widely distributed DNA toolkits or the inexpensive DNA synthesis service(Synthetic and Will); we are facing unprecedented biosafety issue that unwanted leakage of synthetic biology products to the environment may cause an unexpected but definitely disastrous problem.

Predecessors

For decades, researchers were striving to build biosafety devices through auxotrophy or external inducive kill switches(Lee et al.), holins and restriction enzymes are most commonly used. Most of the failures of the previous devices were caused by mutation and evolution of immune(Moe-Behrens et al.) .

The two major threats of engineered microbes’ leakage are the possible Horizontal Gene Transfer which will lead to the spread of recombinant DNA to the entire ecosystem, or the engineered bacteria could contaminate or overrun the natural habitat.(Wright et al.)

Project Xscape

Under this circumstance, this year we decided to be a fundamentalist to synthetic biology, by using genetic circuits and logic gates, to establish biosafety devices which can apply to the real-world situation.

Since cell death and lysis mean there is a continual presence of free DNA in the environment, holins, which are most widely used are excluded from our choices, and colicin E2 nucleases (Darmstadt iGEM2016) came into our site. We choose site non-specific nucleases since the entire genome and plasmids needed to be entirely digested to prevent the spread, and we use nucleases from a different family to prevent the possible evolution of nuclease inhibitors. Artificial DNA, RNA, and amino acids are a good solution, but due to its high cost so far, it is not applicable to most of the user.

For fermentation

The first device we build is for the fermentation; we want to execute the escaped engineered bacteria from the fermenter, accidentally or intentionally. We used two environment factors to monitor the bacteria’s situation: temperature and population density, they are both high and tunable in the fermenter. So, the device will initiate when temperature and density are both low. We used thermal sensitive regulator (NUS iGEM2017)(Piraner et al.) and quorum sensing regulator (MIT iGEM2004) (Canton et al.)as our sensor, sRNA(Storz et al.) and tetR family repressor PhlF(Glasgow iGEM2015)(Stanton et al.) as the signal inverter. We add intergrase (Peking iGEM2017) controlled by the thermal sensitive regulator, which will turn the promoter of a lethal gene when temperature rise in the fermenter so that bacteria can survive at the very beginning. Also, we build a model to stimulate the minimum autoinducer required at the beginning of the fermentation, same as the purpose of integrase. This model is for keeping bacteria alive at the very beginning of fermentation. Together they form a NOR gate which will lead to cell death through genome degradation when temperature and density decrease.

For Therapy

The second device we build is for therapeutic bacteria, the device can carry out noninvasive tracing through ultrasound imaging of the gas vesicle(Shapiro et al.), release the drug (from SHSBNU 2017) controlled by a thermal sensitive regulator at nidus by ultrasound tissue heating, and heat to a higher temperature to release nuclease and kill the bacteria after it finishes its mission.

For Metabolic Stress

We applied capacity monitor (Ceroni et al.) to quantify the expression burden of all our systems, and to reduce the metabolic stress, we designed another device for fermentation which used a LuxR repressive promoter (Peking iGEM2011) and cold-regulated 5’UTR region (Ionis Paris 2017). This device only involves one transcriptional regulator, which will be less energy consuming.

DIY bio and Biosafey

Back to the growing and glowing synthetic biology community, despite the ones doing it on campus, more and more people are starting it at home, they call themselves Genehacker or DIY biologists. The lack of sufficient training and efficient surveillance will be a time bomb which we do know there will be a monstrous harmful bioproduct will be made someday in the future, and indeed, it will be a significant threat to the current biosafety basis. Recall our memory to iGEM2009, Peking surveyed DIY bio, almost ten years later, we conducted a similar DIY bio-survey again. We tried to order materials for molecular experiments, using the delivery address to our home, the result was quite shocking that we can buy almost everything for the molecular experiment, from the internet. Then, we went through relevant laws and regulations throughout the world, which we found out that there are no laws related to the credit certification and the address certification about the people who book the biology reagent. Most of the laws are about the quality certification and how they would serve the user after they bought this. We interviewed the Director of the center for disease control and prevention. He said that within his experiment with the disease caused by the Bacteria leak, environmental pollution, the vast impact had been caused. Our country has been making all effort which is the highest effort that we have made in the history. He said it is not easy to solve the problem with hard work, it needs the cooperation between all the countries. He made an example of 731 army during the second world war two, the outbreak of pathogens can cause significant social harm. We are still on our way to win the battle, but the effort still needs to be put in.

Community and Future

Also, we hosted two major meeting in Beijing, a Biosafety Forum in October, we invited team leader who runs his high school lab, lab teacher from a university lab, and a former team member from Peking iGEM2009, who participated in that DIY bio investigation ten years ago.

We concluded that the development of DIY bio should be taken seriously, and the permanent way to solve it is through implanting Biosafety awareness into our academic culture. Also, as iGEMer, we should strive to be the considerable and responsible leaders in our community, to ensure the biosafety issue has been taken properly. Another meeting was with biology Olympians all around China, we discussed the future of biology community during the meeting, especially with more and more high school iGEM teams coming up in China, but lack of relevant instruction and education to the students. We came up with the idea of setting up a collaboration between school to share and overcome difficulties hand in hand. This kind of meeting will be continued after iGEM2018, since the community usually grows fast after every iGEM season.

Hopefully, years later, biosafety awareness and considerations can be seriously taken in communities, laboratory studies, and real-world applications.



References

Canton, Barry, et al. “Refinement and Standardization of Synthetic Biological Parts and Devices.” Nature Biotechnology, vol. 26, no. 7, 2008, pp. 787–93, doi:10.1038/nbt1413.

Ceroni, Francesca, et al. “Quantifying Cellular Capacity Identifies Gene Expression Designs with Reduced Burden.” Nature Methods, vol. 12, no. 5, 2015, pp. 415–18, doi:10.1038/nmeth.3339.

Lee, Jeong Wook, et al. “Next-Generation Biocontainment Systems for Engineered Organisms.” Nature Chemical Biology, Springer US, 2018, p. 1, doi:10.1038/s41589-018-0056-x.

Moe-Behrens, Gerd H. G., et al. “Preparing Synthetic Biology for the World.” Frontiers in Microbiology, vol. 4, no. JAN, 2013, pp. 1–10, doi:10.3389/fmicb.2013.00005.

Piraner, Dan I., et al. “Tunable Thermal Bioswitches for in Vivo Control of Microbial Therapeutics.” Food, Pharmaceutical and Bioengineering Division 2017 - Core Programming Area at the 2017 AIChE Annual Meeting, vol. 2, no. November, Nature Publishing Group, 2017, pp. 695–702, doi:10.1038/nchembio.2233.

Shapiro, Mikhail G., et al. “Biogenic Gas Nanostructures as Ultrasonic Molecular Reporters.” Nature Nanotechnology, vol. 9, no. 4, Nature Publishing Group, 2014, pp. 311–16, doi:10.1038/nnano.2014.32.

Stanton, Brynne C., et al. “Genomic Mining of Prokaryotic Repressors for Orthogonal Logic Gates.” Nature Chemical Biology, vol. 10, no. 2, 2014, pp. 99–105, doi:10.1038/nchembio.1411.

Storz, Gisela, et al. “Regulation by Small RNAs in Bacteria: Expanding Frontiers.” Molecular Cell, vol. 43, no. 6, 2011, pp. 880–91, doi:10.1016/j.molcel.2011.08.022.

Synthetic, How, and Biology Will. “Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves.” Choice Reviews Online, 2013, doi:10.5860/CHOICE.50-3835.

Wright, Oliver, et al. “Building-in Biosafety for Synthetic Biology.” Microbiology (United Kingdom), vol. 159, no. PART7, 2013, pp. 1021–35, doi:10.1099/mic.0.066308-0.

footer