2STEP Cycle (Tm value > 63°C)

3STEP Cycle (Tm value < 63°C)

STEP DOWN

1. Put gel into electrophoresis tank.
2. Pour 2x TBE buffer into the tank to soak gel.
3. Add 5 µL of EtBr into cathode.
4. Pre-migration for 30 min at 100 V.
5. Apply DNA solutions with 6x loading dye and ladder.
6. Start electrophoresis at 100 V.
7. Stop at appropriate time.

1. Add 1/10 volume of NaOAc, and 5/2 of 100% ethanol.
2. Leave it at room temperature for 5 min.
3. Centrifuge at 15,000 rpm for 15 min at 25°C.
4. Remove supernatant and add 600 µL of 70% ethanol.
5. Centrifuge at 15,000 rpm for 5 min at 25°C.
6. Remove supernatant and dry up at room temperature with light sheilding.
7. Suspend with 10 µL of TE.

Ethanol precipitation

1. Centrifuge at 15,000 rpm for 15 min at room temprature.
2. Remove supernatant, add 100 µL of 70% EtOH and tap tubes by finger.
3. Centrifuge at 15,000 rpm for 10 min at room temprature.
4. Remove supernatant and dry up at room temperature.
5. Resuspend the pellet to HiDi formamide and remove to 96-well plate.
6. Set the plate and start electrophoresis.

1. Thaw original competent cells on ice.
2. Add 5 µL of original competent cells to 2 mL of LB.
3. Incubate the cells for 16 hrs at 37°C.
4. Add 5 µL, 50 µL, and 500 µL of original cells to 100 mL of LB.
5. Incubate the cells at 130 rpm at 20°C, until OD₆₀₀ reach 0.5.
6. Take 50 mL of incubated cells to two different culture tubes and centrifuge them at 3,000 rpm for 20 min at 4°C.
7. Remove supernatant and add 75 mL of TB to each tube.
8. Bring them to a one tube and centrifuge at 3,000 rpm for 20 min at 4°C.
9. Remove supernatant and add 32 mL of TB.
10. Add 32 µL of DMSO 10 times.
11. Take 50 µL and freeze with liquid nitrogen.

1. Add plasmid to thawed competent cells on ice.
2. Incubate on ice for 30 min.
3. Add to LB.
4. Incubate the cells for 2 hrs at 37°C.
5. Spread 300 µL of the culture onto plate with LB and appropriate antibiotics.
6. Incubate the plate(s) at 37°C for 16~20 hrs.

1. Pick the colony with an inoculating loop from the agar plate．
2. Drag the loop across on a new agar plate.
3. Resterilize the loop and drag it across again.
4. Repeat method 3.

1. Add 13 µL of PEG to 20 µL of product(s).
2. Leave it at room temperature for 1 hr.
3. Centrifuge at 15,000 rpm for 20 min at 4°C.
4. Remove supernatant and add 100 µL of 70% ethanol.
5. Centrifuge at 15,000 rpm for 2 min at 4°C.
6. Remove supernatant and dry up at room temperature with light sheilding.
7. Suspend with 10 µL of TE.

Preparation of biotinylated DNA fragments

2STEP Cycle (Tm value > 63°C)

Preparation of magnetic beads

1. Mix 2 µL of magnetic beads (SiMAG-Streptavidin) and 48 µL of TE by vibration using sonic-toothbrush.
2. Collect the beads by attracting them to one side in 0.2 mL polypropylene tube using neodymium magnet.
3. Remove supernatant.

Fixation to magnetic beads

1. Add 3 µL of PCR product (0.48 pmol) and 7 µL of TE to beads.
2. Mix by vibration using sonic-toothbrush.
3. Collect the beads using magnet.
4. Remove supernatant containing excess amount of free DNA fragment.

Double restriction digestion

1. Add Digestion Premix containing 1 µL of 10x RE solution, 8 µL of DW and each 0.5 µL of restriction endonuclease, XbaI and SpeI, to the beads.
2. Mix by pumping using pipette.
3. Incubate at 37 °C for 30 min.
4. Collect the beads using magnet.
5. Obtain supernatant containing digested DNA fragment.
6. Purify the supernatant by ethanol precipitation.