Difference between revisions of "Team:Potsdam/Protocols"

Line 69: Line 69:
 
- ALLin™ Red Taq Mastermix, 2X is premixed with red dye and density reagents for direct loading on the gels after the PCR. In a 2% agarose TAE gel the dye migrates with~350 bp  DNA, in 1% agarose TAE gel with ~ 600 bp DNA fragments  
 
- ALLin™ Red Taq Mastermix, 2X is premixed with red dye and density reagents for direct loading on the gels after the PCR. In a 2% agarose TAE gel the dye migrates with~350 bp  DNA, in 1% agarose TAE gel with ~ 600 bp DNA fragments  
 
<br> <br>
 
<br> <br>
<b>step by step for E.coli: <b> <br> <br>
+
<b>step by step for E.coli: </b> <br> <br>
 
<div style="text-indent:10px;">- resuspend colonies: <br>
 
<div style="text-indent:10px;">- resuspend colonies: <br>
 
- label PCR tubes or wells of a PCR plate <br>
 
- label PCR tubes or wells of a PCR plate <br>
Line 133: Line 133:
 
- If resuspended colonies are to be used: pipette 50 μl of a 0.02 M NaOH  solution into each of a set of appropriately labelled PCR tubes or wells of a PCR plate. Using sterile pipette tips or toothpicks, transfer transformants to individual tubes/wells. The amount of cells   
 
- If resuspended colonies are to be used: pipette 50 μl of a 0.02 M NaOH  solution into each of a set of appropriately labelled PCR tubes or wells of a PCR plate. Using sterile pipette tips or toothpicks, transfer transformants to individual tubes/wells. The amount of cells   
 
resuspended must just be visible. Resuspend cells by pipetting or vortexing and incubate for  
 
resuspended must just be visible. Resuspend cells by pipetting or vortexing and incubate for  
≥ 5 min at 37 °C.
+
≥ 5 min at 37 °C. <br>
If overnight cultures are to be used: pipette 40 μl of a 0.1 M NaOH solution into each of a  
+
If overnight cultures are to be used: pipette 40 μl of a 0.1 M NaOH solution into each of a set of appropriately labelled PCR tubes or wells of a PCR plate. Transfer 10 μl of each overnight culture to be tested to the appropriate tube/well and mix by pipetting up and down. Incubate for ≥ 5 min at 37 °C. <br>
set of appropriately labelled PCR tubes or wells of a PCR plate. Transfer 10 μl of each  
+
- Prepare a PCR master mix (always prepare at least 10% more, use the excel sheet to calculate)
overnight culture to be tested to the appropriate tube/well and mix by pipetting up and down.
+
- Aliquot 22.5 μl of PCR master mix into each PCR tube. <br>
Incubate for ≥ 5 min at 37 °C.
+
- Add 2.5 μl of the resuspended colony or overnight culture mixed with NaOH to the  appropriate PCR tube. <br>
2.
+
- Close the tubes <br>
Prepare a PCR master mix (always prepare at least 10% more, use the excel sheet to
+
- Perform the PCR using the following cycling profle: <br>
calculate)
+
<style type="text/css">
3.
+
.tg  {border-collapse:collapse;border-spacing:0;}
Aliquot 22.5 μl of PCR master mix into each PCR tube.
+
.tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;}
4.
+
.tg th{font-family:Arial, sans-serif;font-size:14px;font-weight:normal;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;}
Add 2.5 μl of the resuspended colony or overnight culture mixed with NaOH to the   
+
.tg .tg-yw4l{vertical-align:top}
appropriate PCR tube.
+
</style>
5.
+
<table class="tg">
  Close the tubes.
+
  <tr>
6.
+
    <th class="tg-031e">Initial denaturation<br></th>
Perform the PCR using the following cycling profle:
+
    <th class="tg-yw4l">1 cycle<br></th>
*
+
    <th class="tg-yw4l">95°C</th>
NaOH opens the cells.
+
    <th class="tg-yw4l">60s</th>
7.  
+
  </tr>
Load probes on the agarose gel.
+
  <tr>
8.
+
    <td class="tg-yw4l">Denaturation</td>
Store probes for short time on ice, for long at -20°C.
+
    <td class="tg-yw4l">30-40 cycles<br></td>
 +
    <td class="tg-yw4l">95°C</td>
 +
    <td class="tg-yw4l">15s</td>
 +
  </tr>
 +
  <tr>
 +
    <td class="tg-yw4l">Annealing</td>
 +
    <td class="tg-yw4l">30-40 cycles<br></td>
 +
    <td class="tg-yw4l">55-65°C</td>
 +
    <td class="tg-yw4l">15s</td>
 +
  </tr>
 +
  <tr>
 +
    <td class="tg-yw4l">Extension</td>
 +
    <td class="tg-yw4l">30-40 cycles<br></td>
 +
    <td class="tg-yw4l">72°C</td>
 +
    <td class="tg-yw4l">15-90s</td>
 +
  </tr>
 +
  <tr>
 +
    <td class="tg-yw4l">Final extension<br></td>
 +
    <td class="tg-yw4l">1 cycle<br></td>
 +
    <td class="tg-yw4l">72°C</td>
 +
    <td class="tg-yw4l">5 min<br></td>
 +
  </tr>
 +
</table>
 +
<br> <br>
 +
- Load probes on the agarose gel <br>
 +
- Store probes for short time on ice, for long at -20°C <br>
  
 
</div></div>
 
</div></div>
Line 175: Line 200:
 
<div class="inner" style="display:none;">  
 
<div class="inner" style="display:none;">  
  
Gel Electrophoresis
+
<b> What is it ? </b>
What is it ?
+
– standard lab procedure for separating DNA by size (e.g., length in base pairs) for visualization and purification <br>
+
– uses an electrical field to move the negatively charged DNA through an agarose gel matrix toward a positive electrode <br>
standard lab procedure for separating DNA by size (e.g., length in base pairs) for  
+
- Shorter DNA fragments migrate through the gel more quickly than longer ones <br>
visualization and purification
+
<br>  
+
<b>Why are we doing it ? </b> <br>
uses an electrical field to move the negatively charged DNA through an agarose gel matrix  
+
– to determine the approximate length of a DNA fragment by running it on an agarose gel alongside a DNA ladder (a collection of DNA fragments of known lengths) <br>
toward a positive electrode.
+
<br>
Shorter DNA fragments migrate through the gel more quickly than longer ones.  
+
<b>Protocol : </b> <br>
Why are we doing it ?
+
- Pouring a Standard 1% Agarose Gel: <br>
+
<div style="text-indent:10px;"> - Measure 1g agarose and and mix it with 100ml of TBE in a microwaveable flask. <br>
to determine the approximate length of a DNA fragment by running it on an agarose gel  
+
<div font-color="green"> Note:  Agarose gels are commonly used in concentrations of 0.7% to 2% depending on the size of bands needed to be separated -  Simply adjust the mass of agarose in a given volume to make gels of other agarose concentrations (e.g., 2 g of agarose in 100 mL of TAE will make a 2% gel). <br> </div> </div>
alongside a DNA ladder (a collection of DNA fragments of known lengths).
+
<br> <br>
Protocol : Agarose Gel Electrophoresis
+
- Microwave for 1-3 min until the agarose is completely dissolved (but do not overboil the solution, as some of the buffer will evaporate and thus alter the final percentage of agarose in the gel. Many people prefer to microwave in pulses, swirling the flask occasionally as the solution heats up.). <br>
Pouring a Standard 1% Agarose Gel:
+
<div font-color="green"> Note: gloves and glasses ! Caution HOT! Be careful stirring, eruptive boiling can occur.<br>
1.
+
It is a good idea to microwave for 30-45 sec, stop and swirl, and then continue towards a boil. Keep an eye on it as the initial boil has a tendency to boil over. Placing saran wrap over the top of the flask can help with this, but is not necessary if you pay close attention. </div>
M
+
<br> <br>
easure 1g agarose and and mix it with 100ml of TBE in a microwaveable flask.
+
<b> Pouring of the gel </b> <br>
Note:
+
- Let agarose solution cool down to about 50°C (about when you can comfortably keep your hand on the flask), about 5 mins. <br>
  Agarose gels are commonly used in concentrations of 0.7% to 2% depending on the  
+
<div font-color="green"> Note: or cool down in water bath about 30 min </div> <br>
size of bands needed to be separated -  Simply adjust the mass of agarose in a given volume  
+
- Add ethidium bromide (EtBr) to a final concentration of approximately 0.2-0.5 μg/mL (usually about 2-3 μl of lab stock solution per 100 mL gel). EtBr binds to the DNA and allows you to visualize the DNA under ultraviolet (UV) light. <br>
to make gels of other agarose concentrations (e.g., 2 g of agarose in 100 mL of TAE will  
+
<div font-color="green"> Note:  Caution EtBr is a known mutagen. Wear a lab coat, eye protection and gloves when working  
make a 2% gel).
+
with this chemical. If you add EtBr to your gel, you will also want to add it to the running buffer when you run  
  1L 10x stock TBE: in the lab
+
the gel. </div> <br>
Note: 10x stock of TBE has to be diluted to a 1x  puffer!
+
- Pour the agarose into a gel tray with the well comb in place. <br>
2. Microwave for 1-3 min until the agarose is completely dissolved (but do not overboil the  
+
<div font-color="green"> Note: Think about witch gel tray size you need. (a small one or a big one.)<br>
solution, as some of the buffer will evaporate and thus alter the final percentage of agarose in the  
+
  Pour slowly to avoid bubbles which will disrupt the gel. Any bubbles can be pushed away from the well comb or towards the sides/edges of the gel with a pipette trip. <br> </div>
gel. Many people prefer to microwave in pulses, swirling the flask occasionally as the solution heats
+
- Let the newly poured gel sit at room temperature for 20-30 mins, until it has completely solidified. <br>
up.).
+
<div font-color="green"> if  you are in a hurry the gel can also be set more quickly if you place the gel tray at 4°C  
Note:
+
earlier so that it is already cold when the gel is poured into it. </div> <br> <br>
  gloves and glasses ! Caution HOT! Be careful stirring, eruptive boiling can occur.
+
<b> Loading Samples and Running an Agarose Gel: </b>
Note:
+
<br> <br>
It is a good idea to microwave for 30-45 sec, stop and swirl, and then continue towards a boil.
+
- Add loading buffer to each of your digest samples. <br>
Keep an eye on it as the initial boil has a tendency to boil over. Placing saran wrap over the top of  
+
the flask can help with this, but is not necessary if you pay close attention.
+
Pouring of the gel
+
4. Let agarose solution cool down to about 50°C (about when you can comfortably keep your hand  
+
on the flask), about 5 mins.
+
Note:  
+
or
+
cool down in water bath about 30 min
+
5.
+
(Optional)
+
Add ethidium bromide (EtBr) to a final concentration of approximately 0.2-0.5 μg/mL
+
(usually about 2-3 μl of lab stock solution per 100 mL gel). EtBr binds to the DNA and allows you  
+
to visualize the DNA under ultraviolet (UV) light.
+
Note: Get a Safety Briefing from Fabian or Lena before working with EtBr !!!
+
Note:
+
  Caution EtBr is a known mutagen. Wear a lab coat, eye protection and gloves when working  
+
with this chemical.  
+
Note:
+
If you add EtBr to your gel, you will also want to add it to the running buffer when you run  
+
the gel.  
+
6.
+
Pour the agarose into a gel tray with the well comb in place.
+
Note:  
+
Think about witch
+
gel tray size you need. (a small one or a big one.)
+
Note:
+
  Pour slowly to avoid bubbles which will disrupt the gel. Any bubbles can be pushed away  
+
from the well comb or towards the sides/edges of the gel with a pipette trip.
+
7. Let the newly poured gel sit at room temperature for 20-30 mins, until it has completely  
+
solidified.
+
Note:
+
if  you are in a hurry the gel can also be set more quickly if you place the gel tray at 4°C  
+
earlier so that it is already cold when the gel is poured into it.
+
Loading Samples and Running an Agarose Gel:
+
1.
+
Add loading buffer to each of your digest samples.
+
 
Note:
 
Note:
 
Loading buffer serves two purposes: 1) it provides a visible dye that helps with gel  
 
Loading buffer serves two purposes: 1) it provides a visible dye that helps with gel  

Revision as of 19:36, 25 October 2017

No Sidebar - Escape Velocity by HTML5 UP

Our research work

We are describing our research work. Below you can find the protocols we used.

Protocols