Team:Acton-BoxboroughRHS/Labs

ABRHS iGEM Site

For the active mock Wiki, go here.

3A Assembly Kit(igem)

This lab explores the process of plasmid transformation to E. Coli.

Step 1: Growing the E. coli

Streaking the Agar Stabs

(About 15 active minutes and 16-24 hours of incubation are needed.)

• 70% ethanol
• Paper towels
• Lab marker/Sharpie
• Agar Stab: Part A - BBa_J04500 (kit)
• Agar Stab: Part B - BBa_J04650 (kit)
• Inoculating loops (kit)
• LB agar plates - Amp/Kan (kit)

1. Clean the lab bench by wiping down with 70% ethanol and paper towels.
2. Part A (BBa_J04500) and Part B (BBa_J04650) are both maintained on pSB1AK3 plasmid backbones, which means they are ampicillin- and kanamycin-resistant. Label the agar plates with the names of Part A and Part B.
3. Notice how each zig-zag overlaps with the previous one just a little, and only at the end.
4. Use an inoculating loop to transfer some cells from the Part A agar stab to the appropriately labeled Amp/Kan agar plate. There is a hole in each agar stab from where it was inoculated. Dip an inoculating loop into the stab at the same location, and streak the bacteria onto the agar plate in a zig-zag pattern. Using a fresh inoculating loop, streak onto the agar plate again creating a new zig-zag pattern that overlaps the first. This will help ensure that you will have single colonies to pick from. Streak gently, and try not to puncture the agar.
5. Repeat step 4 for Part B..
6. This prevents other bacteria from settling, and growing, on your agar plate.
7. Place the agar plates into the incubator with the agar side facing up, lid facing down (see insert). Incubate the agar plates at 37 degrees C for 14-16 hours. Alternately, incubate at room temperature for 24-30 hours.
8. Once your agar plates have grown up you can store them in your fridge (4 degrees C) until you're ready to grow up your cell culture.
9. Plates can be stored at 4 degrees C for up to 3 weeks.

Growing up Cell Cultures

(About 30 active minutes and 16 hours of incubation are needed.)

• 70% ethanol
• paper towels
• Lab marker/Sharpie
• 14ml culture tubes (kit)
• 10ml of LB broth - Amp/Kan (kit)
• Inoculating loops (kit)
• Agar plate: Part A - BBa_J04500 (see previous step)
• Agar plate: Part B - BBa_J04650 (see previous step)
• Rotator/Shaker

1. Clean the lab bench by wiping down with 70% ethanol and paper towels.
2. Remove the agar plates for Part A and Part B from the incubator or 4 degrees C fridge.
3. Label one 14ml culture tube for each Part. Add 5ml of LB broth (with ampicillin and kanamycin) to each culture tube.
4. Use an inoculating loop to pick a single colony from each agar plate and inoculate the LB broth, in the appropriately labeled culture tube. Do not use the same inoculating loop more than once! Press lightly on the snap caps of the 14ml tubes, the caps should be a bit loose to allow for air flow.
5. Incubate for 16 hours at 37 degrees C, in a rotator or shaker. Rotation helps the cells grow faster, and prevents them from settling at the bottom.
6. After incubation, the cell culture should be cloudy. You can now firmly press down on the snap caps to seal the tubes and store the cell culture at 4 degreesC until you're ready to move onto the next step.

Step 2: Miniature Preparations

(About 1 active hour is needed.)

• 70% ethanol
• Paper towels
• Marker/Sharpie
• Centrifuge/microcentrifuge
• 2 Beakers/waste collection containers
• Bleach
• Buffers: P1, RNAse A, P2, N3, PB, PE (kit)
• 1.7ml Microcentrifuge tubes (kit)
• Qiagen spin columns (kit)
• Distilled water (kit)
• Cell culture: Part A - BBa_J04500 (see previous step)
• Cell culture: Part B - BBa_J04650 (see previous step)
• Nanodrop machine (optional)

1. Note: If you haven't already, add the RNAse A to both Buffer P1 aliquots. Once you add RNAse A, you must store Buffer P1 at 4 degrees C until use.
2. Clean the lab bench by wiping down with 70% ethanol and paper towels.
3. Make sure the cap of the culture tubes creates a firm seal. Spin down the two culture tubes in a centrifuge. Spin for 3 minutes at 8000 rpm.
4. You should see a pellet of collected cells at the bottom of the tube. Slowly pour the supernatant (media at the top of the tube) into the beaker. Be sure not to do it too quickly or the cell pellet might dislodge. Pour some bleach into the beaker to sterilize the solution.
5. Pipet 250ul of Buffer P1 to each 14ml culture tube. Pipet up and down gently to re-suspend the cell pellets.
6. Label one 1.7ml microcentrifuge tube each with the part name. Transfer the resuspended cells to the appropriate microcentrifuge tube.
7. Pipet 250ul of Buffer P2 to each microcentrifuge tube. Close the tubes, and flip them upside down gently 5x.
8. Carefully open the tubes, and pipet 350ul of Buffer N3 into each one. Close the tubes, and flip them upside down gently 5x to mix. The solution will turn clear and slightly “chunky”.
9. Spin down the samples in a microcentrifuge for 10 minutes at 13,000 rpm. This spin will separate cellular debris onto the side of the tubes.
10. Label one Qiagen spin column for each part. Carefully pipet the supernatant (the clear liquid) to the appropriate spin column. Try not to transfer the white debris pelleted onto the side of the tubes.
11. Spin down the spin column tubes. In a microcentrifuge, spin for 1 minute at 13,000 rpm.
12. Remove the filter tube (top) from the collection tube (bottom). Be sure not to confuse the two samples! Pour the flow-through in the collection tubes into the other beaker. Place the filter tube back into its original collection tube.
13. Pipet 500ul Buffer PB to each spin column. Spin down the samples. In a microcentrifuge, spin for 1 minute at 13,000 rpm.
14. Remove the filter tube from the collection tube. Be sure not to confuse the two samples! Pour the flow-through into the other beaker. Place the filter tube back into its original collection tube.
15. Pipet 750ul Buffer PE to each spin column. Spin down the samples. In a microcentrifuge, spin for 1 minute at 13,000 rpm.
16. Remove the filter tube from the collection tube. Be sure not to confuse the two samples! Pour the flow-through into the other beaker. Place the filter tube back into its original collection tube.
17. The spin columns should appear empty, but spin down the samples for 1 minute at 13,000 rpm again. This will remove any remaining buffer from the filter tubes.
18. Label one clean 1.7ml microcentrifuge tube each with a part name. Transfer the appropriate filter tube to the clean 1.7ml tube.
19. Pipet 50ul of distilled water to the center of each filter tube. Let the samples sit for 1 minute, then spin down the samples. In a microcentrifuge, spin for 1 minute at 13,000 rpm.
20. If you can, calculate the concentration of the DNA, and mark this on the microcentrifuge tubes. They can be stored at -20 degrees C for long-term storage, or at 4 degrees C for short-term storage.
1. To determine the concentration of DNA using a Nanodrop, open the Nanodrop program on the attached computer.
2. Select the "Nucleic Acid" option. Pipet 2ul of distilled water onto the bottom sensor. Gently close the top arm, and click "OK" to activate the machine. After the machine has finished activating, click on "Blank".
3. Lift the arm. Wet a Kimwipe with distilled water, and use this to gently wipe the top and bottom sensor clean.
4. Pipet 2ul of your miniprepped Part A DNA sample onto the bottom sensor, then click on "Measure". Write down the concentration on the side of the tube.
5. Repeat steps 3-4 for your miniprepped Part B DNA sample.
6. Lift the arm. Wipe the top and bottom sensor with the damp Kimwipe.

Message