Team:Macquarie Australia/Notebook

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Contents

Notebook

12/8/2011

Team PCR

Today, we started the PCR process in order to amplify our T7 promoter, HO1, At, Dr.

  • Step 1) We diluted the primer stock down to a concentration of 100uM. We did this by taking the weight of the primers and multiplying them by 100 and then adding this amount of water to the stock.
So, for example, if our amount of Oligo = 38.3nM, we add 383ul of water (which gives us a concentration of 100uM)
  • Step 2) We performed a second dilution (1:10) to produce a concentration of 10uM for each primer.
So, 100uM --> 10uM
  • Step 3) A master-mix was made containing:
Master Mix
Reactants Volume
Water 41.4ul
5x buffer 16ul
10mM DNTP 1.6ul
Taq poly 1ul
  • Step 4) Mix was spun for a couple of seconds. This master mix as divided up into 4 15ul aliquots [you can take out 3 lots of 15ul and keep the final 15ul in the mastermix tube and use that as a housing].
  • Step 5) To these 15ul aliquots, we add into each:
DNA
Primers/Template (steps 1-2) Volume
Forward 2ul
Reverse 2ul
Template [Ho, Dr etc] 1ul


What we end up with is 4 reaction tubes with our plasmid template with the primers in the correct dilution.
  • Step 6) We set up the PCR machine with the following protocol:
Initial denaturation – 94oC for 2 minutes
Denaturation – 94oC for 30 sec
Annealing – 60oC for 30 seconds ] 10 cycles in total
Extension – 72oC for 2min 30sec
THEN
Denaturation – 94oC for 30 sec
Annealing – 52oC for 30 seconds ] 15 cycles in total.
Extension – 72oC for 2min 30sec


Final extension – 72oC for 10 min
Hold period – 4oC for 2 minutes
We’ve labelled the protocol ‘330’ and it’s the same as last years’ protocol with a few additions. Note that we made a mistake during our 15 cycle stage - it should be at 72oC. Our bad. We have fixed this - the protocol has been corrected.
  • Step 7) We conducted our PCR! It took 2 hours and 13 minutes to complete.
  • Step 8) With our PCR complete, we then set about preparing the Chloramphenicol vector [which is the one we need to submit for any medal] as well as the clean up protocol.
Ch vector prep'
Rectants Volume
DPN1 1ul
Xba1 + Spe1 1ul + 1ul
100x BSA 1ul
Template DNA - Ch vector 20ul
10x NEBuffer 4 5ul
Water 21.5ul
Total 50.5ul
Clean up prep:
Sigma GENELUTE PCR clean up kit has the protocol
  • Step 9) We set up the nanodrop to determine the quality of our PCR results:
Nanodrop'
PCR product Concentration
T7 1.1ug [23ng/ul]
HO 870ng [17.4ng/ul]
Agro 500ng [10.4ng/ul]
Dino 1.8ug [36.1ng/ul]
  • Step 10) Cleaned PCR products were diluted with water [20ul PCR product + 30ul water] and were then double digested using X + S [1ul each] in 5ul of 10x buffer and 1ul of BSA.

Media Prep

-LB media Method- Dissolve 10g tryptone, 5g yeast extract and 10g NaCl in 800 mL MilliQ water, making use of a magnetic stirrer. Once dissolved, bring volume up to 1 litre using the MilliQ water. Autoclave 500 mL of the solution (121oC, 15 min, standard liquid cycle).

-LB agar Method- Add 7.5 g Bacto agar to the remaining 500 mL of LB media and autoclave [121oC, 15 min, standard liquid cycle]. Add 250 µL of Chloroamphenicol and mix well before plating out and setting agar.

After cooling and antibiotic addition, the LB agar was plated out using aseptic technique. 14 LB agar plates were prepared and allowed to cool next to the bunsen. After this all plates were aseptically sealed using parafilm and stored in the refridegerator.

BUFFER PREP


TB buffer (for competent cells)- 2 grams of CaCl2-2H2O, 18.6 grams of KCl and 3 grams of PIPES where mixed and dissolved in ca 500ml of water with the pH adjusted to 6.7 with KOH. Then, 10.9 grams of MnCl2-4H2O, isdissolved in 300 ml of water, mixed and the solution adjusted to 1L. This is then sterilized by filtration through a pre-rinsed 0.45 µm filter unit and stored at 4 C. The solution is stable at 4 C indefinitely. All salts are added as solids. Resulting solution was colourless and unautoclaved.


1. Hanahan, D. (1983) J Mol Biol 166, 557-580

2. Sambrook, J. (1989) Molecular Cloning: A Laboratory Manual, 2nd Ed ed., Plainview, NY