Difference between revisions of "Team:Tokyo Tech/Experiment/ssrA tag degradation assay"

 
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       <h3 class="link2"><a href="#Const">4.1.  Construction</a></h3>
 
       <h3 class="link2"><a href="#Const">4.1.  Construction</a></h3>
 
       <h3 class="link2"><a href="#Protocol">4.2. Assay Protocol</a></h3>
 
       <h3 class="link2"><a href="#Protocol">4.2. Assay Protocol</a></h3>
         <h3 class="link3"><a href="#Protol1">4.2.1. C4HSL-dependent CmR expression assay ([Cm] = 75 microg/mL)</a></h3>
+
         <h3 class="link3"><a href="#Protol1">4.2.1. C4HSL-dependent CmR expression assay (Prisoner A)</a></h3>
         <h3 class="link3"><a href="#Protol2">4.2.2. 3OC12HSL concentration-dependent CmR expression assay</a></h3>
+
         <h3 class="link3"><a href="#Protol2">4.2.2. 3OC12HSL-dependent CmR expression assay (Prisoner B)</a></h3>
 +
        <h3 class="link3"><a href="#Protol3">4.2.3. C4HSL-dependent CmRssrA expression assay (Prisoner A)</a></h3>
 +
        <h3 class="link3"><a href="#Protol4">4.2.4. 3OC12HSL-dependent CmRssrA expression assay (Prisoner B)</a></h3>
 
       <h3 class="link"><a href="#Reference">5. Reference</a></h3>
 
       <h3 class="link"><a href="#Reference">5. Reference</a></h3>
 
       <br>
 
       <br>
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       <td width="940px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/1/11/Tokyo_Tech_ssrA1.png" width="350px"/>
+
       <td width="940px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/9/93/Tokyo_Tech_realizing_summary1.png" width="450px"/>
 
       </td>
 
       </td>
 
       </tr>
 
       </tr>
 
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       <tr>
 
       <td width="940px">
 
       <td width="940px">
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-1-1.</strong>&nbsp;The genetic circuits of prisoner <i>colis</i> with the options of cooperation or defection </h4>
+
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-1-1.</strong>&nbsp;The genetic circuits of prisoner <i>colis</i> with the options of cooperation or defection</h4>
 
       <td>
 
       <td>
 
       </tr>
 
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       </table>
 
       </table>
 
                 <h3 id="Summary2" class="sub5">2.2. Insertion of an ssrA degradation tag to CmR</h3>
 
                 <h3 id="Summary2" class="sub5">2.2. Insertion of an ssrA degradation tag to CmR</h3>
                 <p class="text2">At the wet experiment of 2-1., Prisoner <i>coli</i>s containing the pairs of plasmids (1) and (2), showed leaky expression of CmR.  Cells grew actively even in the absence of AHL when the cell harboring the pairs of plasmids (1) and (2).  We came up with two solutions, either increasing the chloramphenicol (Cm) concentration or inserting an ssrA tag to the CmR gene, to this problem. Our modeling result shows that the influence of the leakage was not reduced by increasing the Cm concentration.  Please refer <a href="https://2015.igem.org/Team:Tokyo_Tech/Project/Modeling">here</a>.</p>
+
                 <p class="text2">At the wet experiment of 2-1., Prisoner <i>coli</i>s containing the pairs of plasmids (1) and (2), showed leaky expression of CmR.  Cells grew actively even in the absence of AHL when the cell harboring the pairs of plasmids (1) and (2).  We came up with two solutions, either increasing the chloramphenicol (Cm) concentration or inserting an ssrA tag to the CmR gene, to this problem. Our modeling result shows that the influence of the leakage was not reduced by increasing the Cm concentration.  Please refer to <a href="https://2015.igem.org/Team:Tokyo_Tech/Project/Modeling">here</a>.</p>
                 <p class="text2">For precise implementation of our payoff matrix, suggestions from modeling (link to modeling) allowed us to successfully solve the influence of the leakage by adding an ssrA degradation tag right after the CmR gene. ((Fig. 3-1-2-5.) and (Fig.3-1-2-6.))  New pairs of plasmids (9), (10), (11) and (12) were prepared as in (Fig. 3-1-2-7.) and (Fig. 3-1-2-8.).  The growth of the Prisoner A colis and Prisoner B colis, containing the improved parts, Pcon_rhlR_TT_Plux_CmRssrA (<a href="http://parts.igem.org/Part:BBa_K1632023">BBa_K1632023</a>), and Pcon_lasR_TT_Plux_CmRssrA (<a href="http://parts.igem.org/Part:BBa_K1632022">BBa_K1632022</a>), respectively, were measured.</p>
+
                 <p class="text2">For precise implementation of our payoff matrix, suggestions from <a href="https://2015.igem.org/Team:Tokyo_Tech/Project/Modeling">modeling</a>  allowed us to successfully solve the influence of the leakage by adding an ssrA degradation tag added to the C-terminal of the CmR protein. ((Fig. 3-1-2-5.) and (Fig.3-1-2-6.))  New pairs of plasmids (9), (10), (11) and (12) were prepared as in (Fig. 3-1-2-7.) and (Fig. 3-1-2-8.).  The growth of the Prisoner A <i>coli</i>s and Prisoner B <i>coli</i>s, containing the improved parts, Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (<a href="http://parts.igem.org/Part:BBa_K1632023">BBa_K1632023</a>), and Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (<a href="http://parts.igem.org/Part:BBa_K1632022">BBa_K1632022</a>), respectively, were measured.</p>
  
 
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               <h3 id="Result2" class="sub6">3.1.1. C4HSL-dependent CmR expression (Prisoner A)</h3>
 
               <h3 id="Result2" class="sub6">3.1.1. C4HSL-dependent CmR expression (Prisoner A)</h3>
 
                 <p class="text2">The cell growth with and without C4HSL was measured every hour for eight hours.  (Fig. 3-1-3-1.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (1) and (3).  (Fig. 3-1-3-2.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (2) and (4).  Each Prisoner <i>coli</i> grew in the culture medium even without C4HSL.</p><br>
 
                 <p class="text2">The cell growth with and without C4HSL was measured every hour for eight hours.  (Fig. 3-1-3-1.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (1) and (3).  (Fig. 3-1-3-2.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (2) and (4).  Each Prisoner <i>coli</i> grew in the culture medium even without C4HSL.</p><br>
                 <p class="text4"><strong>Sample : Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
+
                 <p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
 
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<table width="940 px" border="0px">
 
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       <td>
 
       <td>
 
       </tr></table><br>
 
       </tr></table><br>
                 <p class="text4"><strong>Sample : Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</strong></p>
+
                 <p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</strong></p>
 
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<table width="940 px" border="0px">
 
       <tr>
 
       <tr>
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               <h3 id="Result3" class="sub6">3.1.2. 3OC12HSL-dependent CmR expression (Prisoner B)</h3>
 
               <h3 id="Result3" class="sub6">3.1.2. 3OC12HSL-dependent CmR expression (Prisoner B)</h3>
 
               <p class="text3">The cell growth with and without 3OC12HSL was measured every hour for eight hours.  (Fig. 3-1-3-3.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (5) and (7).  (Fig. 3-1-3-4.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (6) and (8).  Each Prisoner <i>coli</i> grew in the culture medium even without 3OC12HSL.</p><br>
 
               <p class="text3">The cell growth with and without 3OC12HSL was measured every hour for eight hours.  (Fig. 3-1-3-3.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (5) and (7).  (Fig. 3-1-3-4.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (6) and (8).  Each Prisoner <i>coli</i> grew in the culture medium even without 3OC12HSL.</p><br>
                 <p class="text4"><strong>Sample : Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)<strong></p>
+
                 <p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)<strong></p>
 
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<table width="940 px" border="0px">
 
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       <td>
 
       <td>
 
       </tr></table><br>
 
       </tr></table><br>
<p class="text4"><strong>Sample : Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</strong></p>
+
<p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</strong></p>
 
<table width="940 px" border="0px">
 
<table width="940 px" border="0px">
 
       <tr>
 
       <tr>
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               <h3 id="Result5" class="sub6">3.2.1. C4HSL-dependent CmRssrA expression (Prisoner A)</h3>
 
               <h3 id="Result5" class="sub6">3.2.1. C4HSL-dependent CmRssrA expression (Prisoner A)</h3>
 
               <p class="text3">The cell growth of the prisoner <i>colis</i> which contain the pairs of plasmids (1) – (4), (9), and (10) were measured every hour for eight hours.  (Fig. 3-1-3-5.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (1), (3) and (9).  (Fig. 3-1-3-6.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (2), (4) and (10).</p><br>
 
               <p class="text3">The cell growth of the prisoner <i>colis</i> which contain the pairs of plasmids (1) – (4), (9), and (10) were measured every hour for eight hours.  (Fig. 3-1-3-5.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (1), (3) and (9).  (Fig. 3-1-3-6.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (2), (4) and (10).</p><br>
<p class="text4"><strong>Samples : Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
+
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
 
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
 
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
 
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<table width="940 px" border="0px">
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       <tr>
 
       <td width="940px">
 
       <td width="940px">
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-4.</strong>&nbsp;Defecting Prisoner B <i>coli</i>’s growth with Cm</h4>
+
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-5.</strong>&nbsp;Cooperating Prisoner A <i>coli</i>’s growth with and without an ssrA tag</h4>
 
       <td>
 
       <td>
 
     </tr>
 
     </tr>
 
     </table>
 
     </table>
<br>ここちがうから入れ替えといて。
+
<br>
<p class="text4"><strong>Samples : Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
+
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</strong></p>
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</strong></p>
+
<p class="text4"><strong>Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</strong></p>
 
<table width="940 px" border="0px">
 
<table width="940 px" border="0px">
 
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       <tr>
 
       <td width="940px">
 
       <td width="940px">
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-4.</strong>&nbsp;Defecting Prisoner B <i>coli</i>’s growth with Cm</h4>
+
       <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-6.</strong>&nbsp;Defecting Prisoner A <i>coli</i>’s growth with and without an ssrA tag</h4>
 
       <td>
 
       <td>
 
     </tr>
 
     </tr>
 
     </table>
 
     </table>
       <h3 id="Result6" class="sub6">3.2.2. C4HSL-dependent CmRssrA expression (Prisoner B)</h3>
+
<p class="text3">From (Fig. 3-1-3-5.) and (Fig. 3-1-3-6.), prisoner <i>coli</i> with <i>CmRssrA</i> were not able to grow without C4HSL (pink open circle) while the prisoner <i>coli</i> expressing CmR with an ssrA tag grew (green open circle).  We confirmed that our improved parts, Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i>, had expressed CmR when induced by C4HSL.
         
+
</p><br>
 +
       <h3 id="Result6" class="sub6">3.2.2. 3OC12HSL-dependent CmRssrA expression (Prisoner B)</h3>
 +
              <p class="text3">The experiment was also conducted for Prisoner B.  The cell growth of the prisoner <i>colis</i> which contain the pairs of plasmids (5) – (8), (11), and (12) were also measured every hour for eight hours.  (Fig. 3-1-3-7.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (5), (7) and (11).  (Fig. 3-1-3-8.) shows the growth of prisoner <i>colis</i> containing the pairs of plasmids (6), (8) and (12).</p><br>
 +
<p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)</strong></p>
 +
<p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)</strong></p>
 +
<table width="940 px" border="0px">
 +
      <tr>
 +
      <td width="940px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/8/8e/Tokyo_Tech_ssrA18.png" width="600px"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="940px">
 +
      <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-7.</strong>&nbsp;Cooperating Prisoner B <i>coli</i>’s growth with and without an ssrA tag</h4>
 +
      <td>
 +
    </tr>
 +
    </table>
 +
<p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</strong></p>
 +
<p class="text4"><strong>Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</strong></p>
 +
<table width="940 px" border="0px">
 +
      <tr>
 +
      <td width="940px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/f/f5/Tokyo_Tech_ssrA19.png" width="600px"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="940px">
 +
      <h4 align="center" class="fig"><strong>Fig.&nbsp;3-1-3-8.</strong>&nbsp;Defecting Prisoner B <i>coli</i>’s growth with and without an ssrA tag</h4>
 +
      <td>
 +
    </tr>
 +
    </table>
 +
              <p class="text3">From (Fig. 3-1-3-7.) and (Fig. 3-1-3-8.), Prisoner <i>coli</i> with <i>CmRssrA</i> were not able to grow without 3OC12HSL (pink open circle) while the Prisoner <i>coli</i> expressing CmRssrA grew (green open circle).  We confirmed that our improved parts, Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i>, had expressed CmR when induced by 3OC12HSL.</p>
 +
              <p class="text3">From the results above, we can say that the leaked CmR protein was degraded immediately because of the ssrA tag added to the C-terminal of the CmR protein.  These results show the improved function of AHL-dependent CmR expression.</p>
  
  
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 +
          <h2 id="Materials" class="smalltitle">4. Materials and Methods</h2>
 +
              <h3 id="Const" class="sub5">4.1.  Construction</h3>
 +
              <h3 class="sub5">-Strain</h3>
 +
          <p class="text2">All the samples were JM2.300 strain.</p>
 +
              <h3 class="sub5">-Plasmids</h3>
  
  
 +
<p class="text2">(1) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/b/be/Tokyo_Tech_Pcon_rhlR_TT_Plux_CmRssrA_Plac_lasI.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-1.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
 +
          <p class="text2">(2) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/2/24/Tokyo_Tech_Pcon_rhlR_TT_Plux_CmRssrA_lasI.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-2.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
  
  
 +
          <p class="text2">(3) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/3/3d/Tokyo_Tech_ssrA23.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-3.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
  
  
 +
<p class="text2">(4) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/a/a6/Tokyo_Tech_ssrA24.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-4.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
  
  
 +
  
  
Line 303: Line 389:
  
  
 +
          <p class="text2">(5) Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/7/76/Tokyo_Tech_Pcon_rhlR_TT_plux_CmR_Plac_lasI.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-5.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
  
  
          <h2 id="Materials" class="smalltitle">4. Materials and Methods</h2>
+
 
              <h3 id="Const" class="sub5">4.1.  Construction</h3>
+
          <p class="text2">(6) Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</p>
              <h3 class="sub5">-Strain</h3>
+
          <p class="text2">All the samples were JM2.300 strain.</p>
+
              <h3 class="sub5">-Plasmids</h3>
+
          <p class="text2">(1) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</p>
+
 
                 <table width="980 px" border="0px">
 
                 <table width="980 px" border="0px">
 
                   <tr>
 
                   <tr>
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/b/be/Tokyo_Tech_Pcon_rhlR_TT_Plux_CmRssrA_Plac_lasI.png"/>
+
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/3/30/Tokyo_Tech_Pcon_rhlR_TT_Plux_CmR_lasI.png"/>
 
       </td>
 
       </td>
 
       </tr>
 
       </tr>
 
       <tr>
 
       <tr>
 
       <td width="980px">
 
       <td width="980px">
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-1.</strong></h4>
+
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-6.</strong></h4>
 
       <td>
 
       <td>
 
       </tr>
 
       </tr>
 
       </table>
 
       </table>
          <p class="text2">(2) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</p>
+
 
 +
<p class="text2">(7)Negative contorol 1 : Pcon_<i>rhlR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)</p>
 
                 <table width="980 px" border="0px">
 
                 <table width="980 px" border="0px">
 
                   <tr>
 
                   <tr>
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/2/24/Tokyo_Tech_Pcon_rhlR_TT_Plux_CmRssrA_lasI.png"/>
+
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/e/eb/Tokyo_Tech_Pcon_rhlR_TT_CmR_Plac_lasI.2png.png"/>
 
       </td>
 
       </td>
 
       </tr>
 
       </tr>
 
       <tr>
 
       <tr>
 
       <td width="980px">
 
       <td width="980px">
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-2.</strong></h4>
+
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-7.</strong></h4>
 
       <td>
 
       <td>
 
       </tr>
 
       </tr>
 
       </table>
 
       </table>
  
          <p class="text2">(3) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Pcon_<i>gfp</i>_<i>rhlI</i> (pSB3K3)</p>
+
<p class="text2">(8)Negative contorol 2 : Pcon_<i>rhlR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)</p>
 
                 <table width="980 px" border="0px">
 
                 <table width="980 px" border="0px">
 
                   <tr>
 
                   <tr>
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/c/cf/Tokyo_Tech_Pcon_lasR_TT_Plux_CmRssrA_Pcon_gfp_rhlI.png"/>
+
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/4/45/Tokyo_Tech_Pcon_rhlR_TT_CmR_lasI.png"/>
 
       </td>
 
       </td>
 
       </tr>
 
       </tr>
 
       <tr>
 
       <tr>
 
       <td width="980px">
 
       <td width="980px">
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-3.</strong></h4>
+
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-8.</strong></h4>
 
       <td>
 
       <td>
 
       </tr>
 
       </tr>
 
       </table>
 
       </table>
          <p class="text2">(4) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</p>
+
 
 +
 
 +
 
 +
 
 +
 
 +
 
 +
          <p class="text2">(9) Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)</p>
 
                 <table width="980 px" border="0px">
 
                 <table width="980 px" border="0px">
 
                   <tr>
 
                   <tr>
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/7/77/Tokyo_Tech_Pcon_lasR_TT_Plux_CmRssrA_rhlI.png"/>
+
                   <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/d/d4/Tokyo_Tech_ssrA20.png"/>
 
       </td>
 
       </td>
 
       </tr>
 
       </tr>
 
       <tr>
 
       <tr>
 
       <td width="980px">
 
       <td width="980px">
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-4.</strong></h4>
+
       <h4 align="center" class="fig"><strong>Fig. 3-1-4-9.</strong></h4>
 
       <td>
 
       <td>
 
       </tr>
 
       </tr>
 
       </table>
 
       </table>
              <h3 id="Protocol" class="sub5">4.2. Assay Protocol</h3>
+
 
              <h3 id="Protol1" class="sub6">4.2.1. C4HSL-dependent CmR expression assay ([Cm] = 75 microg/mL)</h3>
+
 
 +
          <p class="text2">(10) Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/9/97/Tokyo_Tech_ssrA21.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-10.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
 +
          <p class="text2">(11)Negative contorol 1 : Pcon_<i>lasR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/f/f7/Tokyo_Tech_ssrA22.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-11.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
 +
 
 +
 
 +
          <p class="text2">(12)Negative contorol 2 : Pcon_<i>lasR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)</p>
 +
                <table width="980 px" border="0px">
 +
                  <tr>
 +
                  <td width="980px"><div align="center"><img src="https://static.igem.org/mediawiki/2015/8/88/Tokyo_Tech_ssrA25.png"/>
 +
      </td>
 +
      </tr>
 +
      <tr>
 +
      <td width="980px">
 +
      <h4 align="center" class="fig"><strong>Fig. 3-1-4-12.</strong></h4>
 +
      <td>
 +
      </tr>
 +
      </table>
 +
 
 +
       
 +
 
 +
<h3 id="Protocol" class="sub5">4.2. Assay Protocol</h3>
 +
 
 +
<h3 id="Protol2" class="sub6"> 4.2.1. C4HSL-dependent CmR expression assay (Prisoner A)</h3>
 
                     <p class="text4">
 
                     <p class="text4">
 
<strong>-samples</strong><br>  
 
<strong>-samples</strong><br>  
(1) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3)<br>
+
Pcon_<i>rhlR</i>_TT_Plux_<i>cmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3) <br>
(2) Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)<br>
+
Pcon_<i>rhlR</i>_TT_Plux_<i>cmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3) <br>
</p>
+
Pcon_<i>rhlR</i>_TT_promoter less_<i>cmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3) <br>
                     <p class="text4"><br>
+
Pcon_<i>rhlR</i>_TT_promoter less_<i>cmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)<br>
 +
 
 +
<br>
 +
 
 +
<p class="text4"><strong>-Procedure</strong><br>
 +
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
 +
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD<sub>590</sub> reaches 0.5.<br>
 +
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 +
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
 +
5.Add 30 microL of suspension in the following medium.<br>
 +
&nbsp;&nbsp;&nbsp;①) LB containing Amp and Kan (3 mL) + 50 microM C4HSL (30 microL) + Chloramphenicol (100 microg/mL)<br>
 +
&nbsp;&nbsp;&nbsp;②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)<br>
 +
6. Incubate the samples of cells at 37°C for more than 8 hours.<br>
 +
&nbsp;&nbsp;&nbsp;Measure OD<sub>590</sub> every hour.<br><br></p>
 +
 
 +
 
 +
 
 +
 
 +
 
 +
              <h3 id="Protol2" class="sub6">4.2.2. 3OC12HSL-dependent CmR expression assay (Prisoner B)</h3>
 +
                     <p class="text4">
 +
<p class="text4"><strong>-samples</strong><br>
 +
        Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)<br>
 +
 
 +
<br>
 
<strong>-Procedure</strong><br>
 
<strong>-Procedure</strong><br>
 
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
 
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp (50 microg/mL) and Kan (30 microg/mL) and grow the cells at 37°C until the observed OD590 reaches 0.5.<br>
+
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD<sub>590</sub> reaches 0.5.<br>
 
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
 
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
5. Add 30 microL of suspension in the following medium.<br>
+
5.Add 30 microL of suspension in the following medium.<br>
&nbsp;&nbsp;&nbsp;①)LB (3 mL) + antibiotics (Amp 50 microg/mL + Kan 30 microg/mL) + 50 microM C4HSL (30 microL) + Chloramphenicol (75 microg/mL)<br>
+
&nbsp;&nbsp;&nbsp;①) LB containing Amp and Kan (3 mL) + 5 microM 3OC12HSL (3 microL) + Chloramphenicol (100 microg/mL)<br>
&nbsp;&nbsp;&nbsp;②)LB (3 mL) + antibiotics (Amp 50 microg/mL + Kan 30 microg/mL) + DMSO (30 microL) + Chloramphenicol (75 microg/mL)<br>
+
&nbsp;&nbsp;&nbsp;②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)<br>
6.Grow the samples of cells at 37°C for more than 8 hours.<br>
+
6. Incubate the samples of cells at 37°C for more than 8 hours.<br>
7.Measure optical density every hour. (If the optical density is over 0.9, dilute the cell medium to 1/5.)<br><br>
+
&nbsp;&nbsp;&nbsp;Measure OD<sub>590</sub> every hour.<br><br></p>
  
               <h3 id="Protol2" class="sub6">4.2.2. 3OC12HSL concentration-dependent CmR expression assay</h3>
+
 
 +
 
 +
               <h3 id="Protol3" class="sub6">4.2.3. C4HSL-dependent CmRssrA expression assay(Prosiner A)</h3>
 
                     <p class="text4">
 
                     <p class="text4">
<strong>-samples</strong><br>  
+
<p class="text4"><strong>-samples</strong><br>  
(3) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Pcon_<i>gfp</i>_<i>rhlI</i> (pSB3K3)<br>
+
Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3) <br>
(4) Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)<br>
+
Pcon_<i>rhlR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3) <br>
 +
Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3) <br>
 +
Pcon_<i>rhlR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3) <br>
 +
Pcon_<i>rhlR</i>_TT_promoter less_<i>CmR</i> (pSB6A1) + Plac_<i>lasI</i> (pSB3K3) <br>
 +
Pcon_<i>rhlR</i>_TT_promoter less_<i>CmR</i>  (pSB6A1) + promoter less_<i>lasI</i> (pSB3K3)<br>
 +
 
 
<br>
 
<br>
 
<strong>-Procedure</strong><br>
 
<strong>-Procedure</strong><br>
 
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
 
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp (50 microg/mL) and Kan (30 microg/mL) and grow the cells at 37°C until the observed OD590 reaches 0.5.<br>
+
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD<sub>590</sub> reaches 0.5.<br>
 
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
 
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
 
5.Add 30 microL of suspension in the following medium.<br>
 
5.Add 30 microL of suspension in the following medium.<br>
&nbsp;&nbsp;&nbsp;a) LB (3 mL) + antibiotics (Amp 50 microg/mL + Kan 30 microg/mL) + 1 microM 3OC12HSL (3 microL) + Chloramphenicol (75 microg/mL)<br>
+
&nbsp;&nbsp;&nbsp;) LB containing Amp and Kan (3 mL) + 50 microM C4HSL (30 microL) + Chloramphenicol (100 microg/mL)<br>
&nbsp;&nbsp;&nbsp;b) LB (3 mL) + antibiotics (Amp 50 microg/mL + Kan 30 microg/mL) + DMSO (3 microL) + Chloramphenicol (75 microg/mL)<br>
+
&nbsp;&nbsp;&nbsp;②) LB containing Amp and Kan (3 mL) + DMSO (30 microL) + Chloramphenicol (100 microg/mL)<br>
6. Grow the samples of cells at 37°C for more than 8 hours.<br>
+
6. Incubate the samples of cells at 37°C for more than 8 hours.<br>
&nbsp;&nbsp;&nbsp;Measure optical density every hour. (If the optical density is over 0.9, dilute the cell medium to 1/5.)<br><br></p>
+
&nbsp;&nbsp;&nbsp;Measure OD<sub>590</sub> every hour.<br><br></p>
 +
 
 +
 
 +
 
 +
 
 +
 
 +
 
 +
              <h3 id="Protol4" class="sub6">4.2.4. 3OC12HSL-dependent CmRssrA expression assay (Prisoner B)</h3>
 +
                    <p class="text4">
 +
<p class="text4"><strong>-samples</strong><br>
 +
Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_Plux_<i>CmRssrA</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_Plux_<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_promoter less _<i>CmR</i> (pSB6A1) + Plac_<i>rhlI</i> (pSB3K3) <br>
 +
Pcon_<i>lasR</i>_TT_promoter less _<i>CmR</i> (pSB6A1) + promoter less_<i>rhlI</i> (pSB3K3)<br>
 +
 
 +
<br>
 +
<strong>-Procedure</strong><br>
 +
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.<br>
 +
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD<sub>590</sub> reaches 0.5.<br>
 +
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.<br>
 +
4. Suspend the pellet in 1mL of LB containing Amp and Kan.<br>
 +
5.Add 30 microL of suspension in the following medium.<br>
 +
&nbsp;&nbsp;&nbsp;) LB containing Amp and Kan (3 mL) + 5 microM 3OC12HSL (3 microL) + Chloramphenicol (100 microg/mL)<br>
 +
&nbsp;&nbsp;&nbsp;②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)<br>
 +
6. Incubate the samples of cells at 37°C for more than 8 hours.<br>
 +
&nbsp;&nbsp;&nbsp;Measure OD<sub>590</sub> every hour.<br><br></p>
 +
 
 +
 
 +
 
 +
 
 +
 
 +
 
  
 
           <h2 id="Reference" class="smalltitle">5. Reference</h2>
 
           <h2 id="Reference" class="smalltitle">5. Reference</h2>
      <p class="text">1. Bo Hu <em>et al.</em> (2010) An Environment-Sensitive Synthetic Microbial Ecosystem. PLoS ONE 5(5): e10619</p>
+
      <p class="text">1. Bo Hu <em>et al.</em> (2010) An Environment-Sensitive Synthetic Microbial Ecosystem. PLoS ONE 5(5): e10619</p><br><br>
 
     </div>
 
     </div>
 
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Latest revision as of 00:49, 5 October 2015

ssrA tag degradation assay

  
  

1. Introduction

      

In order to enable prisoner colis acquire chloramphenicol resistance by receiving the corresponding AHL, we designed a signal-dependent growth system. In our Prisoner’s Dilemma game, Prisoner A coli needs C4HSL and Prisoner B coli needs 3OC12HSL to acquire chloramphenicol resistance. There will be difference in the growth depending on the presence of AHL.
   For precise implementation of our payoff matrix, we constructed improved parts Pcon_lasR_TT_Plux_CmRssrA, and Pcon_rhlR_TT_Plux_CmRssrA. The growth of the prisoner colis were confirmed by measuring the optical density.
  

Fig. 3-1-1-1. The genetic circuits of prisoner colis with the options of cooperation or defection

   

2. Summary of the Experiment

2.1. AHL-dependent CmR expression

2.1.1. C4HSL-dependent CmR expression (Prisoner A)

Fig. 3-1-2-1. C4HSL-dependent CmR expression

We confirmed the function of C4HSL-dependent CmR expression parts by measuring the optical density of the cultures containing chloramphenicol (Cm) (Fig. 3-1-2-1.). In this experiment we prepared four cells which contain different pairs of plasmids, (1), (2), (3), and (4) (Fig. 3-1-2-2.). The four cells were cultured with or without C4HSL induction. The optical density was measured to estimate the concentration of the cell. Cells containing (1), and (2) are the cooperating and defecting Prisoner A coli, respectively. (3), and (4) are the pairs of plasmids of the negative control for (1), and (2), respectively.

Fig. 3-1-2-2. Pairs of plasmids for the C4HSL-dependent CmR expression assay

2.1.2. 3OC12HSL-dependent CmR expression (Prisoner B)

Fig. 3-1-2-3. 3OC12HSL-dependent CmR expression

We confirmed the function of 3OC12HSL-dependent CmR expression by measuring the optical density of the cultures containing chloramphenicol (Cm) (Fig. 3-1-2-3.). In this experiment we prepared four cells which contain different pairs of plasmids, (5), (6), (7), and (8) (Fig. 3-1-2-4.). The four cells were cultured with or without 3OC12HSL induction. The optical density was measured to estimate the concentration of the cell. Cells containing (5), and (6) are the cooperating and defecting Prisoner B coli, respectively. (7), and (8) are the pairs of plasmids of the negative control for (5), and (6), respectively.

Fig. 3-1-2-4. Pairs of plasmids for the experiment of 3OC12HSL-dependent CmR expression

2.2. Insertion of an ssrA degradation tag to CmR

At the wet experiment of 2-1., Prisoner colis containing the pairs of plasmids (1) and (2), showed leaky expression of CmR. Cells grew actively even in the absence of AHL when the cell harboring the pairs of plasmids (1) and (2). We came up with two solutions, either increasing the chloramphenicol (Cm) concentration or inserting an ssrA tag to the CmR gene, to this problem. Our modeling result shows that the influence of the leakage was not reduced by increasing the Cm concentration. Please refer to here.

For precise implementation of our payoff matrix, suggestions from modeling allowed us to successfully solve the influence of the leakage by adding an ssrA degradation tag added to the C-terminal of the CmR protein. ((Fig. 3-1-2-5.) and (Fig.3-1-2-6.)) New pairs of plasmids (9), (10), (11) and (12) were prepared as in (Fig. 3-1-2-7.) and (Fig. 3-1-2-8.). The growth of the Prisoner A colis and Prisoner B colis, containing the improved parts, Pcon_rhlR_TT_Plux_CmRssrA (BBa_K1632023), and Pcon_lasR_TT_Plux_CmRssrA (BBa_K1632022), respectively, were measured.

Fig. 3-1-2-5. The improved parts (BBa_K1632023) we constructed

Fig. 3-1-2-6. The improved parts (BBa_K1632022) we constructed

Fig. 3-1-2-7. Pairs of plasmids for the ssrA degradation tag assay of Prisoner A

Fig. 3-1-2-8. Pairs of plasmids for the ssrA degradation tag assay of Prisoner B

3. Results

3.1. AHL-dependent CmR expression

3.1.1. C4HSL-dependent CmR expression (Prisoner A)

The cell growth with and without C4HSL was measured every hour for eight hours. (Fig. 3-1-3-1.) shows the growth of prisoner colis containing the pairs of plasmids (1) and (3). (Fig. 3-1-3-2.) shows the growth of prisoner colis containing the pairs of plasmids (2) and (4). Each Prisoner coli grew in the culture medium even without C4HSL.


Pcon_rhlR_TT_Plux_CmR (pSB6A1) + Plac_lasI (pSB3K3)

Fig. 3-1-3-1. Cooperating Prisoner A coli’s growth with chloramphenicol


Pcon_rhlR_TT_Plux_CmR (pSB6A1) + promoter less_lasI (pSB3K3)

Fig. 3-1-3-2. Defecting Prisoner A coli’s growth with chloramphenicol

The expression of CmR was confirmed from (Fig. 3-1-3-1.) and (Fig. 3-1-3-2.), since the prisoner coli grew in the presence of chloramphenicol (solid green line of (Fig. 3-1-3-1.) and (Fig. 3-1-3-2.)). However, the Prisoner coli also showed active growth even in the absence of C4HSL (dotted green line), in other words, the prisoner coli acquired Cm resistance independent on C4HSL induction. From this result, leakage in the promoter was expected


3.1.2. 3OC12HSL-dependent CmR expression (Prisoner B)

The cell growth with and without 3OC12HSL was measured every hour for eight hours. (Fig. 3-1-3-3.) shows the growth of prisoner colis containing the pairs of plasmids (5) and (7). (Fig. 3-1-3-4.) shows the growth of prisoner colis containing the pairs of plasmids (6) and (8). Each Prisoner coli grew in the culture medium even without 3OC12HSL.


Pcon_lasR_TT_Plux_CmR (pSB6A1) + Plac_rhlI (pSB3K3)

Fig. 3-1-3-3. Cooperating Prisoner B coli’s growth with Cm


Pcon_lasR_TT_Plux_CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

Fig. 3-1-3-4. Defecting Prisoner B coli’s growth with Cm

The expression of CmR was confirmed from (Fig. 3-1-3-3.) and (Fig. 3-1-3-4.), since the prisoner coli grew in the presence of chloramphenicol (solid green line of (Fig. 3-1-3-3.) and (Fig. 3-1-3-4.)). However, the Prisoner coli also showed active growth even in the absence of 3OC12HSL (dotted green line), in other words, the prisoner coli acquired Cm resistance independent on C4HSL induction. From this result, leakage in the promoter was expected.


3.2. AHL-dependent CmRssrA expression

3.2.1. C4HSL-dependent CmRssrA expression (Prisoner A)

The cell growth of the prisoner colis which contain the pairs of plasmids (1) – (4), (9), and (10) were measured every hour for eight hours. (Fig. 3-1-3-5.) shows the growth of prisoner colis containing the pairs of plasmids (1), (3) and (9). (Fig. 3-1-3-6.) shows the growth of prisoner colis containing the pairs of plasmids (2), (4) and (10).


Pcon_rhlR_TT_Plux_CmR (pSB6A1) + Plac_lasI (pSB3K3)

Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + Plac_lasI (pSB3K3)

Fig. 3-1-3-5. Cooperating Prisoner A coli’s growth with and without an ssrA tag


Pcon_rhlR_TT_Plux_CmR (pSB6A1) + promoter less_lasI (pSB3K3)

Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + promoter less_lasI (pSB3K3)

Fig. 3-1-3-6. Defecting Prisoner A coli’s growth with and without an ssrA tag

From (Fig. 3-1-3-5.) and (Fig. 3-1-3-6.), prisoner coli with CmRssrA were not able to grow without C4HSL (pink open circle) while the prisoner coli expressing CmR with an ssrA tag grew (green open circle). We confirmed that our improved parts, Pcon_rhlR_TT_Plux_CmRssrA, had expressed CmR when induced by C4HSL.


3.2.2. 3OC12HSL-dependent CmRssrA expression (Prisoner B)

The experiment was also conducted for Prisoner B. The cell growth of the prisoner colis which contain the pairs of plasmids (5) – (8), (11), and (12) were also measured every hour for eight hours. (Fig. 3-1-3-7.) shows the growth of prisoner colis containing the pairs of plasmids (5), (7) and (11). (Fig. 3-1-3-8.) shows the growth of prisoner colis containing the pairs of plasmids (6), (8) and (12).


Pcon_lasR_TT_Plux_CmR (pSB6A1) + Plac_rhlI (pSB3K3)

Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + Plac_rhlI (pSB3K3)

Fig. 3-1-3-7. Cooperating Prisoner B coli’s growth with and without an ssrA tag

Pcon_lasR_TT_Plux_CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + promoter less_rhlI (pSB3K3)

Fig. 3-1-3-8. Defecting Prisoner B coli’s growth with and without an ssrA tag

From (Fig. 3-1-3-7.) and (Fig. 3-1-3-8.), Prisoner coli with CmRssrA were not able to grow without 3OC12HSL (pink open circle) while the Prisoner coli expressing CmRssrA grew (green open circle). We confirmed that our improved parts, Pcon_lasR_TT_Plux_CmRssrA, had expressed CmR when induced by 3OC12HSL.

From the results above, we can say that the leaked CmR protein was degraded immediately because of the ssrA tag added to the C-terminal of the CmR protein. These results show the improved function of AHL-dependent CmR expression.

4. Materials and Methods

4.1. Construction

-Strain

      

All the samples were JM2.300 strain.

-Plasmids

(1) Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + Plac_lasI (pSB3K3)

Fig. 3-1-4-1.

      

(2) Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + promoter less_lasI (pSB3K3)

Fig. 3-1-4-2.

      

(3) Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + Plac_rhlI (pSB3K3)

Fig. 3-1-4-3.

(4) Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + promoter less_rhlI (pSB3K3)

Fig. 3-1-4-4.

      

(5) Pcon_rhlR_TT_Plux_CmR (pSB6A1) + Plac_lasI (pSB3K3)

Fig. 3-1-4-5.

      

(6) Pcon_rhlR_TT_Plux_CmR (pSB6A1) + promoter less_lasI (pSB3K3)

Fig. 3-1-4-6.

(7)Negative contorol 1 : Pcon_rhlR_TT_promoter less_CmR (pSB6A1) + Plac_lasI (pSB3K3)

Fig. 3-1-4-7.

(8)Negative contorol 2 : Pcon_rhlR_TT_promoter less_CmR (pSB6A1) + promoter less_lasI (pSB3K3)

Fig. 3-1-4-8.

      

(9) Pcon_lasR_TT_Plux_CmR (pSB6A1) + Plac_rhlI (pSB3K3)

Fig. 3-1-4-9.

      

(10) Pcon_lasR_TT_Plux_CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

Fig. 3-1-4-10.

      

(11)Negative contorol 1 : Pcon_lasR_TT_promoter less_CmR (pSB6A1) + Plac_rhlI (pSB3K3)

Fig. 3-1-4-11.

      

(12)Negative contorol 2 : Pcon_lasR_TT_promoter less_CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

Fig. 3-1-4-12.

      

4.2. Assay Protocol

4.2.1. C4HSL-dependent CmR expression assay (Prisoner A)

-samples
Pcon_rhlR_TT_Plux_cmR (pSB6A1) + Plac_lasI (pSB3K3) 
Pcon_rhlR_TT_Plux_cmR (pSB6A1) + promoter less_lasI (pSB3K3) 
Pcon_rhlR_TT_promoter less_cmR (pSB6A1) + Plac_lasI (pSB3K3) 
Pcon_rhlR_TT_promoter less_cmR (pSB6A1) + promoter less_lasI (pSB3K3)

-Procedure
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD590 reaches 0.5.
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.
4. Suspend the pellet in 1mL of LB containing Amp and Kan.
5.Add 30 microL of suspension in the following medium.
   ①) LB containing Amp and Kan (3 mL) + 50 microM C4HSL (30 microL) + Chloramphenicol (100 microg/mL)
   ②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)
6. Incubate the samples of cells at 37°C for more than 8 hours.
   Measure OD590 every hour.

4.2.2. 3OC12HSL-dependent CmR expression assay (Prisoner B)

-samples
Pcon_lasR_TT_Plux_CmR (pSB6A1) + Plac_rhlI (pSB3K3) 
Pcon_lasR_TT_Plux_CmR (pSB6A1) + promoter less_rhlI (pSB3K3) 
Pcon_lasR_TT_promoter less_CmR (pSB6A1) + Plac_rhlI (pSB3K3) 
Pcon_lasR_TT_promoter less_CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

-Procedure
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD590 reaches 0.5.
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.
4. Suspend the pellet in 1mL of LB containing Amp and Kan.
5.Add 30 microL of suspension in the following medium.
   ①) LB containing Amp and Kan (3 mL) + 5 microM 3OC12HSL (3 microL) + Chloramphenicol (100 microg/mL)
   ②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)
6. Incubate the samples of cells at 37°C for more than 8 hours.
   Measure OD590 every hour.

4.2.3. C4HSL-dependent CmRssrA expression assay(Prosiner A)

-samples
Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + Plac_lasI (pSB3K3) 
Pcon_rhlR_TT_Plux_CmRssrA (pSB6A1) + promoter less_lasI (pSB3K3) 
Pcon_rhlR_TT_Plux_CmR (pSB6A1) + Plac_lasI (pSB3K3) 
Pcon_rhlR_TT_Plux_CmR (pSB6A1) + promoter less_lasI (pSB3K3) 
Pcon_rhlR_TT_promoter less_CmR (pSB6A1) + Plac_lasI (pSB3K3) 
Pcon_rhlR_TT_promoter less_CmR (pSB6A1) + promoter less_lasI (pSB3K3)

-Procedure
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD590 reaches 0.5.
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.
4. Suspend the pellet in 1mL of LB containing Amp and Kan.
5.Add 30 microL of suspension in the following medium.
   ①) LB containing Amp and Kan (3 mL) + 50 microM C4HSL (30 microL) + Chloramphenicol (100 microg/mL)
   ②) LB containing Amp and Kan (3 mL) + DMSO (30 microL) + Chloramphenicol (100 microg/mL)
6. Incubate the samples of cells at 37°C for more than 8 hours.
   Measure OD590 every hour.

4.2.4. 3OC12HSL-dependent CmRssrA expression assay (Prisoner B)

-samples
Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + Plac_rhlI (pSB3K3) 
Pcon_lasR_TT_Plux_CmRssrA (pSB6A1) + promoter less_rhlI (pSB3K3) 
Pcon_lasR_TT_Plux_CmR (pSB6A1) + Plac_rhlI (pSB3K3) 
Pcon_lasR_TT_Plux_CmR (pSB6A1) + promoter less_rhlI (pSB3K3) 
Pcon_lasR_TT_promoter less _CmR (pSB6A1) + Plac_rhlI (pSB3K3) 
Pcon_lasR_TT_promoter less _CmR (pSB6A1) + promoter less_rhlI (pSB3K3)

-Procedure
1. Prepare overnight cultures (n=2) for the samples in 3 mL LB medium, containing ampicillin (50 microg/mL) and kanamycin (30 microg/mL) at 37°C for 12 hours.
2. Make a 1:100 dilution in 3 mL of fresh LB containing Amp and Kan and grow the cells at 37°C until the observed OD590 reaches 0.5.
3. Centrifuge 1 mL of the sample at 5000g, RT for 1 minute.
4. Suspend the pellet in 1mL of LB containing Amp and Kan.
5.Add 30 microL of suspension in the following medium.
   ①) LB containing Amp and Kan (3 mL) + 5 microM 3OC12HSL (3 microL) + Chloramphenicol (100 microg/mL)
   ②) LB containing Amp and Kan (3 mL) + DMSO (3 microL) + Chloramphenicol (100 microg/mL)
6. Incubate the samples of cells at 37°C for more than 8 hours.
   Measure OD590 every hour.

5. Reference

      

1. Bo Hu et al. (2010) An Environment-Sensitive Synthetic Microbial Ecosystem. PLoS ONE 5(5): e10619