Team:Calgary/Notebook/Protocols/Process7
From 2011.igem.org
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<li>Sodium-EDTA</li> | <li>Sodium-EDTA</li> | ||
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<h4>Isolation Buffer (500mL)</h4> | <h4>Isolation Buffer (500mL)</h4> | ||
<li>27.4g of 300mM sorbitol</li> | <li>27.4g of 300mM sorbitol</li> | ||
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<li>Hemocytometer (cell counter)</li> | <li>Hemocytometer (cell counter)</li> | ||
<li>Fine (artist style) paint brush</li> | <li>Fine (artist style) paint brush</li> | ||
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<p><h4>Protocol</h4></p> | <p><h4>Protocol</h4></p> | ||
<ol> | <ol> |
Revision as of 02:10, 28 September 2011
Plasmid Extraction
This protocol will purify plasmids from bacteria, though identification of plasmids will need to be confirmed by PCR.
Reagents
Isolation Buffer (500mL)
Equipment
Protocol
- Inoculate algal cells at a density of 4*10^4 cells/mL in 1L of minimal media. Grow cells under white light for 5 days.
- Harvest the cells (0.6-1.0 * 10^7 cells/mL) by centrifuging at 3000g for 10 min at 4°C.
- Wash the pellet with 100mL of 50mM HEPES-KOH (pH 7.5) by mixing and centrifuging at 3000g for 5 min at 4°C.
- Resuspend the pellet in 2mL of 50mM HEPES-KOH (pH 7.5) and hold at 4°C.
- Measure the chlorophyll concentration of the cells by a spectrophotometer.
- Dilute aliquots of cells with 3-0.3mg chlorophyll/mL using isolation buffer with 1% (w/v) BSA.
- Quickly draw the diluted cells into the syringe, attach a 27-gauge needle, and pass through the needle at 0.1mL/s flow rate (~80psi).
- Collect whole cells and crude chloroplasts by centrifugation at 750g for 2 min at 4°C.
- Resuspend the pellet in 2mL isolation buffer using a paintbrush to prevent disruption of chloroplasts (smooth out any clumps).
- Overlay the suspenion on top of the gradients and centrifuge at 4200g for 15min at 4°C, the chloroplasts are at 45-65% interface.
- Collect the chloroplast band using a disposable glass pipet, dilute with 10mL isolation buffer with 0.1% (w/v) BSA.
- Centriduge at 670g for 1 min at 4°C to collect the organelles to remove Percoll.
- Resuspend the pellet gently using the paintbrush in 250 µL of 50mM HEPES-KOH pH 8.0 with 0.3M sorbitol.