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<li>Cells were kept on ice for 2 minutes</li> | <li>Cells were kept on ice for 2 minutes</li> | ||
<li>200μl of broth was added and the cells incubated at 37⁰C for expression step (time varies dependent on antibiotic resistance gene in the plasmid that has just been transformed into the cells): | <li>200μl of broth was added and the cells incubated at 37⁰C for expression step (time varies dependent on antibiotic resistance gene in the plasmid that has just been transformed into the cells): | ||
− | < | + | <table> |
− | < | + | <tr> |
− | < | + | <th>Resistance</th> |
− | < | + | <th>Time</th> |
− | </ | + | </tr> |
+ | <tr> | ||
+ | <td>Chloramphenicol</td> | ||
+ | <td>90 minutes</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>Kanamycin</td> | ||
+ | <td>60 minutes</td> | ||
+ | </tr> | ||
+ | <tr> | ||
+ | <td>Ampicillin</td> | ||
+ | <td>30 minutes</td> | ||
+ | </tr> | ||
+ | </table> | ||
</li> | </li> | ||
<li>100-200μl of transformed cells was spread on dried L-agar plates with required antibiotic(s) to select for plasmid(s) </li> | <li>100-200μl of transformed cells was spread on dried L-agar plates with required antibiotic(s) to select for plasmid(s) </li> | ||
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<li>Incubate at 37⁰C, shaking at 250rpm until mid-log phase (OD600=0.5-0.7)</li> | <li>Incubate at 37⁰C, shaking at 250rpm until mid-log phase (OD600=0.5-0.7)</li> | ||
<li>Split culture into 2 x 200ml samples</li> | <li>Split culture into 2 x 200ml samples</li> | ||
− | <li>Chill on ice for | + | <li>Chill on ice for 20 minutes</li> |
− | <li>Spin 4000g for | + | <li>Spin 4000g for 15 minutes at 4⁰C</li> |
<li>Re-suspend each in 200ml ice cold 10% glycerol</li> | <li>Re-suspend each in 200ml ice cold 10% glycerol</li> | ||
− | <li>Spin 4000g for | + | <li>Spin 4000g for 15 minutes at 4⁰C</li> |
<li>Re-suspend each in 100ml ice cold 10% glycerol</li> | <li>Re-suspend each in 100ml ice cold 10% glycerol</li> | ||
− | <li>Spin 4000g for | + | <li>Spin 4000g for 15 minutes at 4⁰C</li> |
<li>Re-suspend each in 10ml ice cold 10% glycerol</li> | <li>Re-suspend each in 10ml ice cold 10% glycerol</li> | ||
− | <li>Spin 4000g for | + | <li>Spin 4000g for 15 minutes at 4⁰C</li> |
<li>Re-suspend each in 500μl ice cold 10% glycerol</li> | <li>Re-suspend each in 500μl ice cold 10% glycerol</li> | ||
<li>Aliquot 60μl into small eppendorf tubes and store at -70⁰C</li> | <li>Aliquot 60μl into small eppendorf tubes and store at -70⁰C</li> | ||
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<li>Bake in the oven for 15-20 minutes, or until pale golden-brown. Set aside to cool on a wire rack.</li> | <li>Bake in the oven for 15-20 minutes, or until pale golden-brown. Set aside to cool on a wire rack.</li> | ||
</ol> | </ol> | ||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
</div> | </div> | ||
</div> | </div> |
Revision as of 14:22, 1 August 2016
Protocols
Here's the techniques we used blah blah blah"
Preparation of CaCl2 Competent Cells
- Dilute 400μl of overnight liquid culture into 20ml of broth with any necessary antibiotics to select for any plasmids already transformed into the cells
- Incubate at 37⁰C, shaking at 225rpm for 90 minutes
- Spin down for 2 minutes at 7000rpm at 4⁰C
- Discard supernatant, resuspend pellet in 10ml of 50 mM CaCl2, keep on ice
- Repeat centrifugation for 2 minutes at 7000rpm at 4⁰C
- Discard supernatant and the resuspend pellet in 1ml of 50 mM CaCl2, keep on ice
- CaCl2 competent cells can be kept on ice in the fridge overnight
Transformation of CaCl2 Competent Cells
- 1μl of plasmid DNA was added to 100μl of competent cells
- Samples were incubated on ice for 20 minutes
- Heat shock was cried out at 37⁰C for 5 minutes
- Cells were kept on ice for 2 minutes
- 200μl of broth was added and the cells incubated at 37⁰C for expression step (time varies dependent on antibiotic resistance gene in the plasmid that has just been transformed into the cells):
Resistance Time Chloramphenicol 90 minutes Kanamycin 60 minutes Ampicillin 30 minutes - 100-200μl of transformed cells was spread on dried L-agar plates with required antibiotic(s) to select for plasmid(s)
- Plates were incubated at 37°C overnight
Preparation of Electrocompetent Cells
- Inoculate 400ml L-broth with 4ml culture
- Incubate at 37⁰C, shaking at 250rpm until mid-log phase (OD600=0.5-0.7)
- Split culture into 2 x 200ml samples
- Chill on ice for 20 minutes
- Spin 4000g for 15 minutes at 4⁰C
- Re-suspend each in 200ml ice cold 10% glycerol
- Spin 4000g for 15 minutes at 4⁰C
- Re-suspend each in 100ml ice cold 10% glycerol
- Spin 4000g for 15 minutes at 4⁰C
- Re-suspend each in 10ml ice cold 10% glycerol
- Spin 4000g for 15 minutes at 4⁰C
- Re-suspend each in 500μl ice cold 10% glycerol
- Aliquot 60μl into small eppendorf tubes and store at -70⁰C
Shortbread
A good supply of shortbread is essential to any productive lab environment.
- Heat the oven to 190C/375F/Gas 5
- Beat the butter and the sugar together until smooth.
- Stir in the flour to get a smooth paste. Turn on to a work surface and gently roll out until the paste is 1cm/½in thick.
- Cut into rounds or fingers and place onto a baking tray. Sprinkle with caster sugar and chill in the fridge for 20 minutes.
- Bake in the oven for 15-20 minutes, or until pale golden-brown. Set aside to cool on a wire rack.