Biomod/2011/Slovenia/BioNanoWizards/methprotprodandisol

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</ul> <!-- End PureCSSMenu.com MENU --> </div> </div> </div> <!-- end #header --> <div id="page" class="container"> <div id="content"> <div class="post"> <div class="entry"><big><big><big><big><span

style="color: black; font-weight: bold;">Protein production

and isolation<br> </span></big>&nbsp;<br> <br> <span style="color: black; font-weight: bold;">Transformation of BL21(DE3)pLysS</span> </big></big></big><br> <br> <span style="font-family: Arial;">All our proteins were produced by transformed Escherichia coli BL21(DE3)pLysS. Transformation was performed by slowly thawing aliquots of competent bacterial cells on ice for 30 min, adding 1 μl of plasmid DNA to each microcentrifuge tube and leaving the mixtures on ice for another 30 min. Heat shock was performed next by heating the cells to 42 °C for 3 to 5 min. Immediately after that they were cooled on ice for 1 to 2 minutes. 1 ml of LB medium was then added to each microcentrifuge tube. The cultures were incubated for 1 h at 37 °C while shaking and then centrifuged for 3 min at 7000 rpm on a tabletop microcentrifuge. Most of the supernatant medium was removed and the rest was used to resuspend the pelleted cells, which were then plated on LB-agar plates with kanamycin and incubated overnight at 37 °C. A successful transformation resulted in many colonies of transformed protein producing cells.<br> <br style="font-family: Arial;"> </span><br style="font-family: Arial;"> <span style="font-family: Arial;"> <big><big><big><span

style="color: black; font-weight: bold;">Protein expression</span>

</big></big></big><br> </span><br style="font-family: Arial;"> <span style="font-family: Arial;"> A single colony was picked with a sterile toothpick, which was used to inoculate 100 to 125 ml of growth medium in a flask. Alternatively, a glycerol stock of the bacteria in question could be used. Inoculated medium was shaken overnight at 37 °C and 180 rpm and its OD600 was measured in the morning. A part of the overnight culture was used as an inoculum for larger flasks so that the starting OD600 of larger volumes of production medium was 0.10-0.15. Flasks were shaked at 37 °C and 160 or 180 rpm. When OD600 reached 0.7-0.9, production of proteins was induced by adding IPTG to a final concentration of 1 mM. After several hours of shaking at 37 °C and 160/180 rpm biomass was harvested by centrifugation for 10 min at 5500 rpm in a BeckmanCoulter centrifuge with JA-10 rotor. Pelleted biomass was either frozen or directly processed further. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> GST-ZFP fusions were overexpressed in bacteria grown in LB medium supplemented with kanamycin (100mg/L), ZnCl2(0.5 mM) and induced with 1 mM IPTG, while 2xYT growth medium supplemented with 10g/L glucose, kanamycin (100mg/L), ZnCl2(0.5 mM) and induced with 1 mM IPTG was used for overexpression of MBP-ZFP fusions as well as twin ZFP protein tethers and BRET fusions, namely MBP-RLuc-2C7 and MBP-YFP-AZPA4.<br> &nbsp;</span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <big><big><big><span

style="color: black; font-weight: bold;">Cell lysis</span>

</big></big></big><br> <br> <span style="font-family: Arial;"> After pelleting bacterial cells were lyzed by resuspending pelleted biomass in lysis buffer (20 mM Tris-HCl, 100 mM NaCl, 0.1 % deoxycholic acid, 100 μM ZnCl2, 1:500 CPI-His tag and 1 mM DTT at pH 7.5 - used for GST-ZFP chimeras - or 25mM HEPES, 300mM NaCl, 0.2% Triton X-100, 1mM TCEP-HCl, 500μM ZnCl2, 1:500 CPI-His tag at pH 8.0 for MBP-ZFP fusions as well as twin ZFP protein tethers and BRET fusions, namely MBP-RLuc-2C7 and MBP-YFP-AZPA4). After 20 min the suspensions were sonicated for approximately 10 min with a pulse every second or third second until they became clear lysates. Lysates were then centrifuged for 20 min at 4 °C and 12000 rpm in a Hettich Universal 320 R centrifuge. Supernatants were separated from pellets of cellular debris and inclusion bodies. Samples for SDS-PAGE and Western blot were taken from both fractions and the rest frozen.<br> &nbsp;</span><br style="font-family: Arial;"> <br> <big><big><big><span

style="color: black; font-weight: bold;">SDS page</span>

</big></big></big><br> <br> <span style="font-family: Arial;"> SDS-PAGE stands for sodium dodecyl sulfate polyacrylamide gel electrophoresis. In this method protein samples are exposed to sodium dodecyl sulfate, a negatively charged detergent that denatures proteins and gives them a uniformly negative charge resulting in a defined charge/mass ratio. Samples are loaded onto a polyacrylamide gel and exposed to an electric field. Negatively charged protein-SDS complexes travel through the gel towards a positive electrode. The samples concentrate in stacking gel and start separating when they enter separating gel according to their size because the bigger the molecules are, the harder they move through gel. The gel can then be stained to visualize proteins with Coomassie Brilliant Blue (CBB) or used in Western blotting. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> Polyacrylamide minigels were made with BioRad equipment for use with MiniProtean II vertical electrophoresis system. In our experiments stacking gels with 4 % and separating gels with 10 - 15 % acrylamide were used. Separating gels were buffered with 375 mM Tris-HCl at pH 8.8 and stacking gels with 125 mM Tris-HCl at pH 6.8. They both contained 0.1 % SDS and were polymerized using 0.05 % (w/V) APS and 0.05 % (separating) or 0.1 % (stacking) TEMED. The separating gel mixture was poured between two glass plates usually 1 mm apart and covered with 200 ul isopropanol. After at least 30 minutes the mixture for stacking gel was prepared, isopropanol removed with filter papers, stacking gel mixture poured and a comb for sample pockets inserted between the glass plates. After at least 30 minutes the gel was ready to be used or wrapped into a moist paper towel and aluminum foil and refrigerated for later use. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> Samples were prepared by adding a 4x loading buffer that contains 4 % (w/V) SDS, 125 mM Tris-HCl at pH 6.8, 40 % (vol.) glycerol, 10 % (w/V) beta-mercaptoethanol and 0.1 % (trace amounts) of bromophenol blue. Samples with 1x loading buffer concentration were loaded into pockets of the stacking gel. Electrophoresis was run in 25 mM Tris, 192 mM glycine and 0.1 % (w/V) SDS at pH 8.3 for approximately 50 minutes at 200 V. Afterwards the gel was stained with CBB and destained with a mixture of 30 % ethanol and 20 % acetic acid until protein bands were clearly visible. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <br> <big><big><big><span

style="color: black; font-weight: bold;">Western blot</span>

</big></big></big><br> <br> <span style="font-family: Arial;"> Western blotting is a general term for describing methods of transferring proteins from an acrylamide gel to a nitrocellulose or PVDF membrane for probing with antibodies. </span><br

style="font-family: Arial;">

<br style="font-family: Arial;"> <span style="font-family: Arial;"> We used two types of Western blotting - "wet blotting" and iBlot(R). The first consists of placing a prerun gel in a sandwich of soaked sponges and filter papers with a nitrocellulose HybondTM ECL being on the anode side of the prerun gel. BioRad PowerPacTM 3000 setup was used for this type of blotting. Process was performed in cold transfer buffer consisting of 25 mM Tris-HCl, 192 mM glycine and 20 % methanol at 350 mA for 50 minutes. The second type is actually a variant of electroblotting and was performed according to manufacturer's instructions. Using the second type, proteins are transferred to the membrane in 7 minutes. </span><br style="font-family: Arial;"> <br> <span style="font-family: Arial;"> After blotting the membrane was incubated in 5 % skimmed milk in 1x TBS buffer (10 mM Tris-HCl, 150 mM NaCl, pH 7.4) for 1.5 h at room temperature. This step prevents non-specific binding of antibodies to the membrane in later steps thus preventing high background signal or false positives. Next the membrane was incubated in a plastic bag with 6 ml mouse anti-(H)4 IgG antibodies (Qiagen, Tetra-His antibody), diluted 1:2000 with 1 % skimmed milk in 1x TBS, for 1 h at room temperature while shaking. Excess antibodies were washed away in 4 steps of 5 minute shaking in 1x TBS buffer. Membrane was then incubated in a plastic bag with 6 ml secondary goat anti-mouse IgG-HRP antibodies (Santa Cruz Biotechnology), diluted 1:3000 with 1 % skimmed milk in 1x TBS, for 50 minutes at room temperature while shaking. Excess antibodies were again washed away in 4 steps of 5 minute shaking in 1x TBS buffer. The membrane was then soaked in ECL reagent for 1 minute and photographed in Syngene G:Box gel imaging system. Horseradish peroxidase catalyzed reaction produced light at His-tagged protein location.<br> &nbsp;</span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> <big><big><big><span

style="color: black; font-weight: bold;">Protein isolation</span>

</big></big></big><br> </span><br style="font-family: Arial;"> <span style="font-family: Arial;"> After production of proteins and their presence in lysate supernatants had been confirmed by Western blot, supernatants were thawed and centrifuged once more for 20 min at 4 °C and 12000 rpm. Cleared supernatants were then loaded onto 3 ml Qiagen Ni-NTA agarose columns, which were then shaken overnight at 4 °C. Before use, Ni-NTA agarose columns were washed with regeneration buffer containing 6 M guanidine hydrochloride, 100 mM Na3PO4, 10 mM Tris and 500 mM imidazole at pH 5.8. Columns were then washed with copious amounts of MQ water to remove denaturant and imidazole and in case of GST-ZFP fusions equilibrated with 10 column volumes of binding buffer consisting of 20 mM Tris-HCl, 50 mM NaCl, 10 μM ZnCl2 and 1 mM DTT (added just before use). In case of MBP-ZFP fusions, twin ZFP protein tethers and BRET fusions, namely MBP-RLuc-2C7 and MBP-YFP-AZPA4, the column was equilibrated with 10 volumes of binding buffer consisting of 25mM HEPES, 300mM NaCl, 0.2% Triton X-100, 1mM TCEP-HCl, 500μM ZnCl2, 1:500 CPI-His tag at pH 8.0. Supernatants were loaded on column and incubated with moderate shaking at 4°C overnight. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> Next morning the supernatants were left to flow through the columns, which were then washed with binding buffer until A280 dropped to 0,02 or lower. Then, in case of GST-ZFP fusions, they were washed with a buffer of same composition as the binding buffer with addition of 20 mM imidazole. Columns were washed with this buffer until A280 dropped to 0,02 or lower. This step was repeated with buffers containing 50 mM imidazole and 100 mM imidazole. His-tagged proteins were eluted with a buffer containing 250 mM imidazole. Useful elution fractions collected in microcentrifuge tubes were joined together and dialyzed in 3500 MWCO dialysis membranes (Spectra/Por) against a buffer without imidazole, which in case of GST-ZFP fusions consisted of 20 mM Tris-HCl, 50 mM NaCl, 100 μM ZnCl2 and 1 mM DTT at pH 7.7. </span><br> <span style="font-family: Arial;"> MBP-ZFP fusions, twin ZFP protein tethers and BRET fusions were, after overnight shaking, treated the same as GST-ZFP fusions, except that buffer of a distinct composition was used for washing the column and later on elution of the proteins. The buffers' composition were as follows: 25 mM HEPES, 300 mM NaCl, 1mM DTT, 0.5 mM ZnCl2 with increasing concentrations of imidazole - 20, 50, 100 and 250 mM. MBP-ZFP fusions were dialyzed in 3500 MWCO dialysis membranes against MQ and twin ZFP protein tethers and BRET fusions with MBP against 10 mM Tris-HCl, 100 mM NaCl, 1mM DTT and 100 μM ZnCl2 at pH 8.0. </span><br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> Attempts to isolate BRET fusions without MBP solubility tag were made under denaturing conditions (with 8 M urea being the denaturant) using buffers as follows. Binding buffer for column equilibration and the first washing step: 10 mM Tris, 100 mM, NaH2PO4, 8 M urea, pH 8.0. Subsequent wash buffers for gradual elution of both proteins were of the same composition as the binding buffer, except for the addition of imidazole in increasing concentration from 10, 50, 100 and 250 mM. The later had different pH as well - 5.8.<br> <br> &nbsp;</span><br> <span style="font-family: Arial;"> <big><big><big><span

style="color: black; font-weight: bold;">Proteins used in our

project</span> </big></big></big><br> </span><br style="font-family: Arial;"> <span style="font-family: Arial;"> Here is a summary of proteins characterized within our project. Estimated binding affinities for selected zinc finger proteins (ZFPs) are also presented and are based on the data from the literature.<br> &nbsp;</span><br style="font-family: Arial;"><br> <br style="font-family: Arial;"> <span style="font-family: Arial;"> <big><big><span style="color: black; font-weight: bold;">ZFPs characteristics</span> </big></big><br><br> </span><br style="font-family: Arial;"> <span style="font-family: Arial;"><span

style="font-weight: bold;">

Three finger ZFPs</span> <br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"></span></span> <table style="text-align: left; width: 100%;" border="1"

cellpadding="2" cellspacing="0">
 <tbody>
   <tr>
     <td style="text-align: left; font-weight: bold;">ZFP

name </td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Number of amino acids</td>
     <td style="text-align: left; font-weight: bold;">Size

[kDa]</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Isoelectric point (pI)</td>
     <td style="text-align: left; font-weight: bold;"
valign="undefined">Estimated Kd</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">sZif268</td>
     <td style="text-align: left;" valign="undefined">91</td>
     <td style="text-align: left;" valign="undefined">11.1</td>
     <td style="text-align: left;" valign="undefined">11.39</td>
     <td style="text-align: left;" valign="undefined">/</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">Zif268</td>
     <td style="text-align: left;" valign="undefined">87</td>
     <td style="text-align: left;" valign="undefined">10.3</td>
     <td style="text-align: left;" valign="undefined">9.81</td>
     <td style="text-align: left;" valign="undefined">2.0

nM (Papworth, 2003)</td>

   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">PBSII</td>
     <td style="text-align: left;" valign="undefined">86</td>
     <td style="text-align: left;" valign="undefined">9.8</td>
     <td style="text-align: left;" valign="undefined">9.48</td>
     <td style="text-align: left;" valign="undefined">/</td>
   </tr>
 </tbody>

</table> <span style="font-family: Arial;"><br> <br style="font-family: Arial;"> <span style="font-family: Arial;"><span

style="font-weight: bold;">

Six finger ZFPs</span> <br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"> <table style="text-align: left; width: 100%;" border="1"

cellpadding="2" cellspacing="0">
 <tbody>
   <tr>
     <td style="text-align: left; font-weight: bold;">ZFP

name </td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Number of amino acids</td>
     <td style="text-align: left; font-weight: bold;">Size

[kDa]</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Isoelectric point (pI)</td>
     <td style="text-align: left; font-weight: bold;"
valign="undefined">Estimated Kd</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">2C7</td>
     <td style="text-align: left;" valign="undefined">180</td>
     <td style="text-align: left;" valign="undefined">21.4</td>
     <td style="text-align: left;" valign="undefined">9.98</td>
     <td style="text-align: left;" valign="undefined">0.46

nM (Liu, 1997)</td>

   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">6F6</td>
     <td style="text-align: left;" valign="undefined">177</td>
     <td style="text-align: left;" valign="undefined">20.8</td>
     <td style="text-align: left;" valign="undefined">10.18</td>
     <td style="text-align: left;" valign="undefined">10-20

pM (Papworth, 2003) </td>

   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">AZPA4</td>
     <td style="text-align: left;" valign="undefined">168</td>
     <td style="text-align: left;" valign="undefined">19.3</td>
     <td style="text-align: left;" valign="undefined">9.24</td>
     <td style="text-align: left;" valign="undefined">&lt;

3pM (Sera, 2002)</td>

   </tr>
 </tbody>

</table> </span><br> <br> </span></span><span style="font-family: Arial;"><span

style="font-weight: bold;">Soluble ZFPs</span>

<br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"></span></span> <table style="text-align: left; width: 70%;" border="1"

cellpadding="2" cellspacing="0">
 <tbody>
   <tr>
     <td style="text-align: left; font-weight: bold;">Protein

name</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Number

of amino acids</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Size

[kDa]</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Isoelectric

point (pI)</td>

   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-Zif268</td>
     <td style="text-align: left;" valign="undefined">324</td>
     <td style="text-align: left;" valign="undefined">37.8</td>
     <td style="text-align: left;" valign="undefined">8.41</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-sZif268</td>
     <td style="text-align: left;" valign="undefined">324</td>
     <td style="text-align: left;" valign="undefined">38.4</td>
     <td style="text-align: left;" valign="undefined">9.31</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-PBSII</td>
     <td style="text-align: left;" valign="undefined">323</td>
     <td style="text-align: left;" valign="undefined">37.3</td>
     <td style="text-align: left;" valign="undefined">8.22</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-2C7</td>
     <td style="text-align: left;" valign="undefined">417</td>
     <td style="text-align: left;" valign="undefined">48.9</td>
     <td style="text-align: left;" valign="undefined">9.03</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-6F6</td>
     <td style="text-align: left;" valign="undefined">414</td>
     <td style="text-align: left;" valign="undefined">48.3</td>
     <td style="text-align: left;" valign="undefined">9.13</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">GST-AZPA4</td>
     <td style="text-align: left;" valign="undefined">405</td>
     <td style="text-align: left;" valign="undefined">46.8</td>
     <td style="text-align: left;" valign="undefined">8.54</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">MBP-6F6</td>
     <td style="text-align: left;" valign="undefined">571</td>
     <td style="text-align: left;" valign="undefined">64.2</td>
     <td style="text-align: left;" valign="undefined">8.83</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">MBP-2C7</td>
     <td style="text-align: left;" valign="undefined">574</td>
     <td style="text-align: left;" valign="undefined">64.8</td>
     <td style="text-align: left;" valign="undefined">8.69</td>
   </tr>
 </tbody>

</table> <span style="font-family: Arial;"><br> <br style="font-family: Arial;"> <span style="font-family: Arial;"><span

style="font-weight: bold;">Twin ZFP protein tethers</span>

<br style="font-family: Arial;"> <br style="font-family: Arial;"> <span style="font-family: Arial;"></span> </span></span> <table style="text-align: left; width: 70%;" border="1"

cellpadding="2" cellspacing="0">
 <tbody>
   <tr>
     <td style="text-align: left; font-weight: bold;">Protein

name</td>

     <td style="text-align: left; font-weight: bold;"
valign="undefined">Number of amino acids</td>
     <td style="text-align: left; font-weight: bold;"
valign="undefined">Size [kDa]</td>
     <td style="text-align: left; font-weight: bold;"
valign="undefined">Isoelectric point (pI)</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">2C7-MBP-6F6</td>
     <td style="text-align: left;" valign="undefined">756</td>
     <td style="text-align: left;" valign="undefined">86.03</td>
     <td style="text-align: left;" valign="undefined">9.23</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">AZPA4-MBP-6F6</td>
     <td style="text-align: left;" valign="undefined">744</td>
     <td style="text-align: left;" valign="undefined">83.93</td>
     <td style="text-align: left;" valign="undefined">8.99</td>
   </tr>
 </tbody>

</table> <br> <span style="font-family: Arial;"><span

style="font-family: Arial;"><br>

</span></span><span style="font-family: Arial;"><span

style="font-family: Arial;"><span
style="font-weight: bold;">BRET proteins</span> <br
style="font-family: Arial;">

<br style="font-family: Arial;"> <span style="font-family: Arial;"></span></span></span> <table style="text-align: left; width: 70%;" border="1"

cellpadding="2" cellspacing="0">
 <tbody>
   <tr>
     <td style="font-weight: bold; text-align: left;">Protein

name</td>

     <td style="font-weight: bold; text-align: left;"
valign="undefined">Number of amino acids</td>
     <td style="font-weight: bold; text-align: left;"
valign="undefined">Size [kDa]</td>
     <td style="font-weight: bold; text-align: left;"
valign="undefined">Isoelectric point (pI)</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">YFP-AZPA4</td>
     <td style="text-align: left;" valign="undefined">429</td>
     <td style="text-align: left;" valign="undefined">48.43</td>
     <td style="text-align: left;" valign="undefined">8.11</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">rLuc-2C7</td>
     <td style="text-align: left;" valign="undefined">513</td>
     <td style="text-align: left;" valign="undefined">59.52</td>
     <td style="text-align: left;" valign="undefined">7.37</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">MBP-YFP-AZPA4</td>
     <td style="text-align: left;" valign="undefined">813</td>
     <td style="text-align: left;" valign="undefined">90.43</td>
     <td style="text-align: left;" valign="undefined">6.58</td>
   </tr>
   <tr>
     <td style="text-align: left;" valign="undefined">MBP-rLuc-2C7</td>
     <td style="text-align: left;" valign="undefined">897</td>
     <td style="text-align: left;" valign="undefined">101.53</td>
     <td style="text-align: left;" valign="undefined">7.62</td>
   </tr>
 </tbody>

</table> <span style="font-family: Arial;"><span

style="font-family: Arial;"><span
style="font-family: Arial;"></span><br>

<br> </span></span><span style="font-family: Arial;"><span

style="font-weight: bold;"></span></span>

<hr style="width: 100%; height: 2px;"><br> <span style="font-family: Arial;"><span

style="font-family: Arial;">Liu Q et al (1997) <span
style="font-style: italic;">Proc. Natl. Acad. Sci. USA</span>

94: 5525-5530<br> Papworth M et al (2003) <span style="font-style: italic;">Proc. Natl. Acad. Sci. USA</span> 100: 1621-1626<br> Sera T &amp; Uranga C (2002) <span style="font-style: italic;">Biochemistry</span> 41: 7074-7081 <br> <!-- TU SE KONEA GLAVNO BESEDILO NA STRANI --> </span></span></div> </div> </div> <!-- end #content --> <div style="clear: both;">&nbsp;</div> </div> <!-- end #page --></div> <div id="footer-content" class="container"> <div id="footer-bg"> <table

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