Christina Jurotich, Meghan Novotny, and Audrey Heathcote
I 121 C
ATT (Ile) → TGT (Cys)
ATT → TGT
T 1122 C
ACA (Thr) → TGT (Cys)
ACA → TGT
Mutagenesis Primers
3/1: Resuspended I121C Primers
3/1: Ran Mutagenesis PCR
Locate your primers in the package and ensure they are the primers you ordered. (Freezer C red box)
Compare the nucleotide sequences and GC% on each primer label to the order invoice. The melting temperature will likely differ between the label and the order (this is not important).
%GC content = Good
Spin down the tubes using the centrifuge machine. This is because dry pellet can often come dislodged during shipping and could be in the cap.
Create a 100uM master stock by adding MBG water into the tube. Take the amount of nanomoles (nmols) on the label and multiply it by 10. That number is how many microliters of MBG water you'll add to the tube.
I121C_FOR1 = 29.4 nmol = 294 uL MBG water
I121C_Rev1 = 30.6 nmol = 206 uL MBG water
Label the top of each primer tube with its name and concentration (100uM).
Labeled I121C FOR1 100 uM & I121C REV 1 100 uM
Wait 10 minutes to allow the master stock to rest at room temperature and then centrifuge before creating the working solutions.
Dilute the primer master stock in a sterile 0.6mL microcentrifuge tube. Add 2uL of master stock and 18uL of MBG Water into the micocentrifuge tube to make 20uL of 10uM solution. If it is a mutation or subcloning primer dilute to 10uM.
Labeled I121C FOR1 10 uM & I121C REV 1 10 uM
Label the aliquot tube with the primer name and concentration. Update the online corresponding Freezer C Box document.
All 4 tubes stored in Freezer C red box
I. Site-directed mutagenesis PCR and DpnI digestion (Video)
1. Determine which PCR mix to use: Q5 Master Mix. Find the PCR mix and the template DNA in the PCR box (Box 12, Freezer C).
2. In a PCR tube, mix the reagents in the order indicated on the table.
9 uL of MBG Water (fridge a)
1 uL of 25ng/uL of CFTR_pGHE (box 6, freezer c)
Dilute 100 ng/uL to 25 ng/uL
100x = 25
0.25 uL of 100 ng/uL + 0.75 uL mbg water
1.25 uL of 10uM of I121C_CFTR_mut_FOR1 primer (CFTR True-Open box, freezer c)
1.25 uL of 10uM of I121C_CFTR_mut_REV1 primer (CFTR True-Open box, freezer c)
12.5 uL of Q5 mastermix (box 12, freezer c)
Annealing temperature changed to 57*C
Extension time changed to 500 seconds(8 minutes) Started 9:33 am 3/1)
3. Before cycling, ensure the PCR tubes do not have any air bubbles. If there are air bubbles present, tap the tubes on the table, and/or centrifuge them in the mini centrifuge. You may also flick them with your finger followed by spinning.
Cycling Conditions
*Annealing temperatures may vary depending on the primers being used.
**Extension time may need to be adjusted depending on the size of the plasmid. Assume a rate of 1 kb/minute to calculate a new time.
57*C & extension time 500 s
4. At the end of the reaction, place the tubes in the PCR Rack (Freezer A) if you’re not doing the next steps right away. (1:30 pm 3/1 Lucas placed in Freezer A)
5. When continuing with the protocol, take 2uL out of every PCR tube to prepare samples for gel electrophoresis analysis (put in PCR tubes & labeled PCR 1 & PCR 2).
6. Added 1 µL of DpnI (Fridge Door, Freezer A) to the remaining PCR product and digest at 37°C overnight in Ingrid. Write DpnI on the side of the tube. [If in a rush, you may add 1 µL of FD DpnI and digest at 37°C for two hours.]
Incubated at 5:07 pm 3/1; removed from incubator and placed in Freezer A at 4:00 pm 3/2
NOTE: If Q5 Master Mix was used, the linear PCR product must be ligated into circular DNA before transformation. See below.
Agarose Gel Preparation (1% agarose gel)
NOTE: Ethidium bromide is a known mutagen and contact with it must be avoided. Wear gloves when handling it.
Weigh about 0.5 g of agarose (Chemical Shelves) and transfer into a 125 mL Erlenmeyer flask (Cabinet A).
Add 50 mL of 0.5X TBE (Cabinet A) to the Erlenmeyer flask containing the agarose. Gently swirl the flask to disperse the agarose evenly.
Heat for 30 seconds in the microwave, let cool down for 10 seconds, then heat for another 10 seconds.
Insert a thermometer (Drawer A) into the solution (don’t let it touch the bottom), wrap a KimWipe around the top to cover it, and let the agarose solution cool down to 70°C.
Periodically swirl the flask to ensure the temperature is even throughout the solution! (every two minutes or so)
While waiting, obtain an electrophoresis tank and gel tray (both in Drawer A) wipe with Kimwipe and gently insert the gel tray in the tank in the casting position with the rubber gaskets touching the tank walls.
Verify that the gaskets are not twisted out of the gel tray and they make a perfect seal with the tank on both sides.
When the agarose temperature nears 70°C, obtain a 10 µL pipette, and ethidium bromide (EtBr, Fridge A).
When the temperature is 70°C, add 2 µL of EtBr into the agarose solution.
After pipetting the EtBr into the solution, set your pipette to 4 µL and flush the solution up and down to wash residual EtBr into the solution. Dispose of the pipette tip in the trash.
Pour the agarose solution into the gel tray and poke any air bubbles into a corner of the gel tray with a toothpick (Drawer A)
Insert the appropriate well comb (Drawer A) into the gel, then let it cool and solidify (it will turn opaque)
Gel Electrophoresis
Gather desired DNA samples. Write and number the names of the DNA according to their planned order in the gel.
Obtain as many 0.6 mL tubes as you have samples and label them. To each tube, add:
3 µL of MBG water (Fridge A)
2 µL of the DNA sample (PCR Product)
1 µL of DNA dye (Fridge A)
Fill the electrophoresis tank with recycled 0.5X TBE (Cabinet A) until the liquid level is the same on both sides of the tank and the gel is covered
Add 5 uL of DNA Ladder to first well (box in Freezer A)
Set the pipette to ~6.5 µL to make a complete transfer of the sample. Load samples according to the written order in the notebook. Do not pierce the gel.
Slide the tank cover on with the negative prod (black) on the same side as the DNA.
Run the gel for 50 minutes at 140 V
1 uL of FD Dpn1 in I121C.1 and I121C.2
Placed in 37*C for 2 hours
Phosphorylation
1. Obtain a 0.6 mL tube and label it. Write CIRC below the DNA name add the reagents in the following order:
5 µL of MBG Water
2 µL of Linear PCR Product (PCR Rack, Freezer A)
1 µL DNA Ligase Buffer (Enzyme Rack, Freezer A)
1 µL 10 mM ATP (Enzyme Rack, Freezer A)
1 µL T4 PNK (Enzyme Rack, Freezer A)
2. Incubate at 37ÂşC For 20 minutes. Write PHOS on the side of the tube.
Ligation
In the same tube, add the reagents in the following order:
6 µL MBG Water (Fridge A)
2 µL 50% PEG 4000 (Enzyme Rack, Freezer A)
1 µL T4 DNA Ligase Buffer (Enzyme Rack, Freezer A)
1 µL T4 DNA Ligase (Enzyme Rack, Freezer A)
Incubate at RT for one hour. Write LIG on the side of the tube.
When done, place the tube in the freezer. 06/16/2022 at 3PM
Determine how many LB Agar plates you need to make the correct amount of LB Agar. 20mL of LB Agar go on each petri dish. (Ex: 3.5g of LB Broth with Agar + 100mL of DI Water to make about 5 plates)
5 plates = 3.5 g LB Broth + Agar + 100 mL DI water
Measure out the determined amount of LB Broth with Agar (Chemical Shelves) using the analytical balance in the main lab.
Add the amount of DI water you need and then add the measured out LB Broth with Agar to a bottle.
Add a stir bar to the solution and stir/heat the agar on the magnetic stirring hot plate in the main lab. Set the stirring setting as high as it can go where the stir bar is spinning in the middle without clanking the sides. Heat to boiling (about medium heat) and allow the powder to dissolve.
Remove the stir bar (using the magnetic rod). Move the bottle to the small autoclave in the shared equipment room (use the insulated gloves!).
Autoclave for 30 minutes at 121°C.
Retrieve from autoclave and allow the bottle to cool to 65°C. Check with a thermometer usually found in the gel electrophoresis drawer.
Grab the desired amount of petri dishes from the main lab (in the back section) and bring them to the Tissue Culture Hood. Spray the hood with ethanol and wipe with a paper towel. Then open the culture plate bag and without touching the inside of the bag gently remove however many petri dishes you need. When done close the bag and return to the drawer in the main lab.
Use a sharpie to label the plates with "LB + Amp" initials and date on the edge of the plate.
Retrieve the antibiotic corresponding to what bacterial DNA you are transforming (Ampicillin Box 5 in Freezer C).
Allow it to defrost and then add 100 uL of Amp to the cooled solution.
Swirl the bottle to mix and then pipette ~20mL of solution to each plate. Use the 25mL pipettes in the main lab.
Allow the plates to cool without the lids on for about 20 minutes in the tissue culture hood. Check that it is solid to ensure they are finished cooling.
Move to the Fridge B to store. Place the agar side up, so condensation does not affect the LB Agar.
1. Add 5 µL of I121C DNA to a previously labeled 0.6 mL tube. Incubate on ice for 10 minutes.
2. Take the cooler with ice and go to the -80°C freezer. Obtain a tube of JM109 competent cells from the JM109 box (red tape). Place the tube on ice and let the cells defrost. While waiting, turn on the water bath and set at 42°C. Periodically check the water bath temperature and adjust the temperature dial accordingly.
3. Add 10 µL of cells to the tubes containing circularized DNA and incubate on ice for 30 minutes. Record the total volume of cells removed from the tube. Subtract that volume from the volume written on the label. Replace the old label with a new one and write the new volume of cells in the tube. Replace the cells in the -80°C freezer.
4. Add 450 µL SOC media (Fridge B) to a previously labeled 2 mL tube and place it in the incubator. Turn on the small incubator/shaker in the equipment room down the hall.
5. Heat shock the cells in the 42°C water bath for 40 seconds and then let them rest on ice for 2 minutes.
Temperature was closer to 50ÂşC first time
Temperature at 43ÂşC the second time
6. Transfer the cells to their corresponding tube with SOC media. Shake in the incubator at 170 rpm, 37°C for 1 hour. Place the culture plates (Fridge B) in the large incubator to dry.
Forgot to transfer cells to SOC media first time; shook for an hour then transferred to SOC media and shook for another hour. The results will be seen after the incubation period and if it failed, transformation will be repeated.
7. After the incubation period, retrieve the cells and culture plates. Label the plates with the name of the DNA, your initials, and the date. Obtain a 100 mL beaker fill it about halfway with 95% ethanol (Fridge A) and ignite the Bunsen burner.
8. Place the culture plate on the rotating stand. Pipette all of the bacterial culture into the plate. Dip the metal spreader in the ethanol. Pass the spreader through the flame. Allow the flame to die and let the spreader cool for about 10 seconds. Spread the bacteria evenly on the plate. Replace the lid and remove the plate from the stand ensuring the agar side is down.
9. Place the plates in the large incubator at 37°C and incubate overnight.
Left to incubate at 5 PM
Transformation failed, redone on 06/20/2022
Left to incubate at 3:30 PM
Retrieved at 9 AM 06/21/2022
No colonies indicated a sterile procedure.
No colonies, we inoculated without SOC media
No colonies, we inoculated without SOC media
Transformation Results
Transformation Results
IV. Single Colony Inoculation (for Maxiprep) (Video)
1. Go to the equipment room down the hall and lift the screen on the biological safety cabinet (a.k.a. the tissue culture hood). Find the control switches at the top. Flip the BLOWER switch to the ON position. Flip the STERILIZING switch to FLUORESCENT.
2. Spray the work area with ethanol and wipe with a paper towel.
3. Put gloves on and obtain a bottle of LB Broth+Amp (100 µg/mL, Fridge A) (add 1uL of Amp (Box 5, Freezer C) for every mL LB Broth), the bacterial culture plates, a box of small pipet tips, and as many 250 mL Erlenmeyer flasks (Cabinet A) as needed. Label the Erlenmeyer flasks with the names of the DNA. Take all the materials to the biological safety cabinet.
4. Rub ethanol on your gloves and allow it to dry. Pour 75 mL of broth into each Erlenmeyer flask. Obtain a pipet tip, remove the lid on one of the plates and visually inspect for an acceptable colony. Good colonies will be medium size and separate from other colonies.
5. Once a colony is found, drag the pipet tip across the colony without touching other colonies. Ensure you have gotten as much of the colony as possible without getting another colony or scarring the agar. Drop the pipet tip straight down into its corresponding Erlenmeyer flask. Replace the lid on the plate and the foil on the flask.
6. After all flasks are inoculated, place them in the small incubator and shake at 37°C at 170 RPM for about 15-16 hours (until cloudy). Take all the materials back, clean the work area with ethanol, and lower the screen on the cabinet. Turn off the biological safety cabinet.
Finished at 7 PM
15 hours = 10 AM
16 hours = 11 AM
Retrieved at __ AM
1. Head to the large centrifuge room on the second floor with cart and bacterial cultures. Transfer 40 mL of the bacterial culture into a Falcon tube. Spin at 5,000 g for 3 minutes. Discard supernatant into waste jar. Repeat with the rest of the bacterial culture in the same tube.
2. Add about 15 mL of TENS buffer. Vortex for 10 seconds or until the pellet is dissolved.
3. Add about 7.5 mL of 3 M sodium acetate pH 5.2. Vortex for 10 seconds.
4. Centrifuge for 5 minutes at 10,000 g and transfer supernatant to a new, previously labeled Falcon tube.
5. Add 10 µL of RNase (Enzyme Rack, Freezer A) and wait for 20 minutes.
6. Add about 5 mL of PCl (Fridge A) from the bottom layer. Vortex for 10 seconds and centrifuge at 10,000 g for 5 minutes.
7. Transfer the top layer to a new, previously labeled Falcon tube. Add about 5 mL of chloroform (Fridge A). Vortex for 10 seconds and centrifuge at 10,000 g for 5 minutes.
8. Transfer the top layer to a new, previously labeled Falcon tube. Add an equal volume of 100% ethanol (Fridge A) and centrifuge at 10,000 g for 5 minutes.
9. Carefully decant supernatant into the ethanol waste bottle. Add 40 mL of 70% ethanol (Fridge A) and centrifuge at 10,000 g for 2 minutes.
10. Carefully decant supernatant in the ethanol waste bottle and let DNA dry. Draw a circle on the outside of the tube where the DNA pellet is. Leave the tubes uncapped and place a Kimwipe over the top.
11. Transfer phenol and chloroform wastes from all tubes into the appropriate waste bottle (bottle in Fridge B).
*Waste jar and bacterial culture flasks from step 1 will need to be autoclaved.
*Falcon tubes that contained TENS buffer and sodium acetate from steps 3-4 can be discarded in the trash.
*Falcon tubes that contained phenol and chloroform need to remain in the fume hood until dry. Once dry they can be discarded in the trash. Steps 6-7
*Pipette tips from phenol and chloroform steps need to be placed in tip waste beaker inside of fume hood. Tips need to be disposed of when dry.
12. Re-suspend the dry DNA in 1 mL of MBG water (Fridge B), vortex, and transfer to a previously labeled 1.5 mL tube.
I121C 1 on left
I121C 2 on right
Pellets are mostly white, I121C 1 may have some impurities
2 µL of MBG water (Fridge A)
3 µL of the DNA sample
1 µL of DNA dye (Fridge A)
The DNA was found to be somewhat impure. I121C 1 had RNA remnants in solution (will add more RNase and do PCI cleanup). Also could have run gel at a higher voltage (was run at 140V for 50 minutes).
I121C 1
1: 1684.2 ng/uL
2: 1814.2 ng/uL
3: 1548.8 ng/uL
Average: 1682.4 ng/uL
I121C 2
1: 243.8 ng/uL
2: 269.2 ng/uL
3: 263.2 ng/uL
Average: 259.4 ng/uL
Results: I121C was successfully mutated from ATT --> TGT
Template DNA was maxiprep product
I121C 1 1682.4 ng/uL Diluted to 25ng/uL
I121C 2 259.4 ng/uL
Gel Analysis PCR was successful, did Dpn1 digestion and will be proceeding with transformation
Gel Analysis PCR was successful, did Dpn1 digestion and will be proceeding with transformation
Nanodrop concentration:
I121C/T1122C - 1 : 619.73 ng/uL Diluted to 40ng/uL for transcription
I121C/T1122C - 2 : 661.73 ng/uL
Several scattered usable colonies indicating that transformation was successful.
Overconcentrated bacterial growth, no usable colonies. Transformation failed and will be retried at a different time.
No bacterial growth, indicating a sterile procedure
Placed in the incubator at 6:51 pm, will remove between 9:51 and 10:51 am
Cloudy broth, indicating bacterial growth and a successful single colony inoculation
Cloudy broth, indicating bacterial growth and a successful single colony inoculation.
Clear broth, indicating no bacterial growth and a sterile procedure
Removed from the incubator at 10:29 am.
The pellets were too small for my taste, so I added 1/10 total volume of sodium acetate buffer and let it sit overnight.
Resuspended in 1mL MBG H2O on
First Pellet
Final pellet
First Pellet
Final Pellet
I121C/T1122C - 1 : 2891.7ng/uL
I121C/T1122C - 2 : 1262.3ng/uL
Gel Analysis Lanes 7, 8
RNA contamination, I will add some more RNAse, and maybe do a PCI cleanup on I121C/T1122C-1
I121C from 1 and 2 were successfully sequenced.
See document on why T1122C was not sequenced.
Did not run a gel first, nanodrop showed the presence of dsDNA.