Team:UT Dallas/protocols

From 2013.igem.org

Protocols

Contents

Ligation Protocol

  • Determine insert to vector ratios</li>
  • Calculate the amount of insert needed if 50ng of vector is used (can use different amount of vector)</li>
  • In a PCR tube add the following:
  • 50ng of vector</li>
  • Amount of insert based on ratios (calculated in second step)</li>
  • 2uL of buffer</li>
  • 2uL of DNA ligase</li>
  • Amount of water to bring total volume to 20uL</li>
  • </li>
  • Incubate overnight at 14 degrees Celsius

    </li>

    Note: We used T4 DNA ligase and buffer from NEB

    Gel Purification Protocol (QIAquick Gel Extraction Kit)

  • Excise DNA fragment from the agarose gel with a clean, sharp scalpel</li>
  • Weigh the gel slice in a microcentrifuge tube.</li>
  • Add 3 volumes of Buffer QG to 1 volume of gel (100mg~100uL)</li>
  • Incubate at 50 degrees Celsius for 10 min (until the gel slice has completely dissolved)</li>
  • After the gel slice has dissolved completely, check that the color of the mixture is yellow</li>
  • Apply the sample to a QIAquick column, and centrifuge for 1 min</li>
  • Maximum volume of the column is 800uL. For samples larger than this, simply load and spin again.
    </li>
  • Discard flow-through and place QIAquick column back in the same collection tube</li>
  • To wash, add 750uL of Buffer PE to column and centrifuge for 1 min.</li>
  • Discard the flow-through and centrifuge for additional 1 min. at 13,000rpm</li>
  • Place QIAquick column into a clean 1.5 mL microcentrifuge tube</li>
  • To elute DNA, add 50uL of Buffer EB to the center of the QIAquick membrane, let the column stand for 1 min. and then centrifuge the column for 1 min.

    </li>

    Gel Electrophoresis Protocol

  • Making a 1% agarose gel
  • 100mL 1X TBE buffer</li>
  • 1g agarose</li>
  • microwave until agarose dissolves</li>
  • let mixture cool</li>
  • when cool add 8-10uL ethidium bromide</li>
  • stir gently, let cool</li>
  • pour into plate with comb already in place</li>
  • let harden</li>
  • </li>
  • Using the gel
  • Add loading buffer to DNA (for 100uL DNA, add 20uL loading buffer)</li>
  • Load 2uL of DNA ladder into the gel</li>
  • Load DNA into the gel</li>
  • Run at 130V for 30min-1hr

    </li>
  • Digestion Protocol

    </li>
  • Using a microcentrifuge tube add the following:
  • ~3000-5000 ng of DNA</li>
  • 10uL Buffer 4</li>
  • 10uL BSA</li>
  • 5uL of appropriate enzyme (if doing a double digest, use 5 uL of both enzymes)</li>
  • Amount of H2O needed to make final volume 100uL</li>
  • </li>
  • Incubate at 37 degrees Celsius for 1hr and 30min

    </li>

    Note: We used the following enzymes from NEB: EcoRI-HF, PstI-HF, SpeI, and XbaI. All of which can be double digested with each other using Buffer 4.

    Preparing LB+Appropriate Antibiotic Protocol

  • 200 mL LB broth</li>
  • Autoclave
  • Put control thermometer in H2O (from the sink)</li>
  • Select vented container mode (Do Not Change Program)</li>
  • </li>
  • Let cool to 50 degrees Celsius</li>
  • Add antibiotic (50-100 ug/mL) (10 mg total)
  • Weigh on paper</li>
  • Add to 0.5 mL DI H2O</li>
  • Add to LB mixture when cool enough</li>
  • </li>
  • Store at 4 degrees Celsius

    </li>

    Preparing Agar Plates Protocol (Makes 12 (15mm) Plates)

  • 300 mL DI H2O + 11 g LB agar</li>
  • Autoclave
  • Put control thermometer in H2O (from the sink)</li>
  • Select vented container mode (Do Not Change Program)</li>
  • </li>
  • Mix well after autoclaving; let cool to 50 degrees Celsius</li>
  • Add antibiotic (50 to 100 µg/mL) (15 mg total)
  • Weigh on paper</li>
  • Add to 0.5 mL DI H2O</li>
  • Add to LB mixture when cool enough</li>
  • </li>
  • Plate
  • Under flame open lids of all plates</li>
  • Slowly pour agar into plate, avoiding bubbles, when it touches all edges stop pouring</li>
  • Let sit under flames until gel solidifies</li>
  • Replace lids on plates</li>
  • </li>
  • Store upside down at 4 degrees Celsius

    </li>

    Preparing Competent Cells Protocol

  • Place 1 colony in 5 mL of LB (with antibiotics if appropriate) Grow overnight at 37 degrees Celsius and 200-300 rpm</li>
  • Inoculate 0.25 mL of the overnight strain into 25 mL of LB</li>
  • Shake at 37oC until the OD650 is 0.6-0.7</li>
  • Harvest cells and resuspend in 12.5 mL ice cold 0.1M MgCl2</li>
  • Harvest immediately and resuspend in 7.5 mL cold 0.1M CaCl2</li>
  • Leave on ice for 30 minutes. Harvest and resuspend in 2.5 mL cold 0.1M CaCl2</li>
  • Leave on ice for 30 minutes</li>
  • For long term storage, use 0.1M CaCl2 in 15% glycerol at step 6 and store cells at -800 degrees Celsius

    </li>

    Note: Harvest cells at 5000 rpm for 10 minutes at 4 degrees Celsius

    Miniprep Protocol (from QIAprep Spin Miniprep Kit)

  • Harvest cells at 5400g 10 minutes 40 degrees Celsius (possibly program 1)</li>
  • Resuspend pelleted bacterial cells in 250 µL Buffer P1 and transfer to a microcentrifuge tube</li>
  • Add 250 µL Buffer P2 and mix thoroughly by inverting the tube 4-6 times</li>
  • Add 350 µL Buffer N3 and mix immediately and thoroughly by inverting the tube 4-6 times</li>
  • Centrifuge for 10 minutes at 13000 rpm (~17900g) in a table-top microcentrifuge</li>
  • Apply the supernatant (from step 4) to the QIA prep spin column by decanting or pipetting</li>
  • Centrifuge for 30-60 seconds. Discard the flow-through</li>
  • Wash QIA prep spin column by adding 0.75 mL Buffer PE and centrifuging for 30-60 seconds</li>
  • Discard the flow-through, and centrifuge for 1 minute to remove residual wash buffer</li>
  • To elute DNA, place the QIA prep column in a clean 1.5 mL microcentrifuge tube. Add 50 µL Buffer EB or water to the center of each QIA prep spin column, let stand for 1 minute and centrifuge for 1 minute.

    </li>

    Preparing Glycerol Stock Protocol

  • Add 150 µL of 50% glycerol to 350 µL of cells</li>
  • Place in -80oC freezer

    </li>

    Transformation Protocol

  • With a pipette tip, punch a hole through the foil cover of the DNA plate</li>
  • Add 10 µL of DI water</li>
  • Thaw competent cells on ice</li>
  • Add 1-2 µL of resuspend DNA and 50 µL of thawed competent cells to labeled tubes</li>
  • Incubate the cells on ice for 30 minutes</li>
  • Heat shock the cells at 42 degrees Celsius for 45 sec</li>
  • Incubate the cells on ice for 2 minutes</li>
  • Under flame, add 450 µL SOC broth</li>
  • Incubate at 37 degrees Celsius for 1 hour while rotating or shaking at 300rpm</li>
  • Spread cells on appropriate antibiotic LB plates (usually 100 µL)</li>
  • Incubate at 37 degrees Celsius for 18-24 hours</li>
  • Take a colony, put in 3 mL of LB + appropriate antibiotic</li>
  • Use resulting culture to miniprep DNA and make your own glycerol stock

    </li>

    Point mutation Protocol

             1) Create reaction mixture
    


            5 ul 10x buffer
            10-100 ng DNA
            1 ul of foward primer
            1 ul of reverse primer
            1 ul of dNTP'S
            1.5 ul of Quik Solution reagent
            Bring to 50 ul with NF-H20
            *Then add 1ul Quik Change Lightning Enzyme
    2)Run thermo-cycler (program--mutate)
            1 cycle: @ 95C 2 minutes
            18 cycles:
                    a) 95C x 20 seconds
                    b) 60C x 10 seconds
                    c) 68C x 30 seconds/kb per plasmid length
            1 cycle: 68C 5 minutes
    3) Then add 2 ul of DpnI enzyme directly to each amplification reaction
    4) Pipette up & down several times
    5) Incubate @ 37C x 5 minutes to digest the parent DNA (cuts methylated dna)

             
    6)Then transform.