Team:Hawaii/PCR Amplification of pRL1383a

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PCR Amplification of pRL1383a

• Several regions of pRL1383a will be amplified with BioBrick based primers. These components will be used later in the construction of a pRL1383a BioBrick based vector. These parts include the aadA region of the omega interposon, the origin of vegetative replication (oriV), the mobilization proteins, and the replication proteins.

Methods

Materials Per Reaction Added in order:

• 3.5uL nanopure water
• 1uL 10uM forward/reverse primers
• 1uL pRL1383a as template (1:10 dilution of large-scale plasmid prep).
• 5uL Taq polymerase: Accusure(hot start, 68°C) and Red Taq

Note: the taq and water can be combined and aliquoted together as long as reaction is kept at 4°C.

• cold blocks
• pcr reaction tubes, with tops
• pipette and tips

Materials for the gel

• 1% agarose gel
• 10ug/mL Ethidium Bromide
• running apparatus
• gel running conditions: 95V for ~1 hour

PCR Clean-up using Qiagen Minelute Kit

1. add 5 volumes of PB to 1 volume of PCR product
2. place sample in minelute spin column
3. centrifuge 1 minute at 13k rpm
4. discard flow-through
5. add 750uL PE buffer to wash; centrifuge 1 minute 13k rpm
6. discard flow-through; centrifuge 1 min 13k rpm
7. place column in clean 1.5 mL tube
8. add 10ul TE or water to center of column, wait 1 minute, centrifuge 1 min

Results

PCR Gel 1 (left) and PCR Gel 2 (right).

PCR Clean-up

MinElute PCR Purification Kit Protocol from Qiagen using a microcentrifuge

This protocol is designed to purify double-stranded DNA fragments from PCR reactions resulting in high end-concentrations of DNA (see page 12). Fragments ranging from 70 bp to 4 kb are purified from primers, nucleotides, polymerases, and salts using MinElute spin columns in a microcentrifuge.

1. Mix PB 5:1 PCR reaction.
2. Place a MinElute column in a provided 2 ml collection tube.
3. Apply ALL of sample to the MinElute column; centrifuge (13,000rpm)1 min.
4. Discard flow-through. Place the MinElute column back into the same tube.
5. Add 750 μl Buffer PE to the MinElute column; centrifuge (13,000rpm) 1 min.
6. Discard flow-through and place the MinElute column back in the same tube.

Centrifuge the column for an additional 1 min at maximum speed.

1. Place the MinElute column in a clean 1.5 ml microcentrifuge tube.
2. Add 10 μl 1x TE to the center of the membrane, let the column stand for 1 min; centrifuge 1 min.

Discussion

• The gels are very warped. I did not let them dry long enough before I poured the running buffer,so some products did not run correctly therefore this experiment will be repeated on Monday when the necessary reagents are delivered.
• I mixed up the temperature gradient!!! I need to be more careful about labeling my reactions.
• The rep protein did not come out at all and the mob region only came out at one temperature, so these must be PCRed again to determine the correct annealing temperature.

Follow-up Experiments

7/2/08

• 1. A second attempt was made to PCR the rep region. An annealing temperature of 53.4° was used for the first 5 cycles and annealing temperature 60.6 was used for the subsequent 30 cycles.
  2. Results: There are 2 faint bands in the low kb region. This is probably primers.

Lane 1 contains the ladder, lanes 3 through 6 contain the products of a plasmid prep, lane 7 contains the PCR of the rep region, while lanes 8 and 9 are the positive and negative control, respectively. Lane 10 contains one of NW's PCR reactions.

• 1. Discussion: The rep region did not amplify under these conditions. There were several suggestions made by the professors that I will try this weekend.

7/4/08

• Materials:

1. • 5uL Red Taq (per reaction)
   • 3.5uL nanopure water (per reaction)
   • 1uL 10uM f/r rep region primers (per reaction)
   • 1uL of either 1:100, 1:500, 1:1000 dilution pRL1383a as template (1:10 dilution of large-scale plasmid prep)
   • 5uL accusure (for one reaction to test the dilution with this enzyme)

PCR Gel of rep region amplified with red taq.

Results

7/7/08

1. rep and mob regions did not amplify with accusure, so they were amplified using red/green taq. Same conditions from 7/4 were used.

results

1. mob and rep regions were amplified by both red and green taq. Use green in the future, it is cheaper.

PCR amplification of mob and rep regions.

Discussion

rep region appears to be amplified by red taq efficiently. Need to use much less DNA. Find out what dilution to use. Accusure + some reaction stabilizing reagent might be used to get this reaction going, but as of right now, this region is not being amplified by this enzyme. This temperature seems to have worked well also.

7/18/08

PCR amplification of the mob/rep region, the omega interposon, the aada gene, oriV, a (-) control, and (+)control. All products that amplified are too bright to use the ladder scale.

• PCR amplification of oriV, omega interposon, aadA gene, & rep/mob all using green taq.
• PCR conditions: 2min@94°C, 30sec@95°C, 30sec@50.4°C, 5min30sec@72°C(1 minute per kilobase), infinity@4°C

7/19/08

• PCR amplification of omega interposon and rep/mob regions using 3 different types of taq: File:Velocity taq.pdf, green taq and accuzyme with the hopes that one will amplify these products. I also changed the annealing temperature to 48°C in order to accomodate the primer with the lowest annealing temperature.

Methods For all reactions, I heated up the PCR block to 94C before adding my sample. I did this by running another method which only involves 94C for infinity.

• Accuzyme:

• Reaction conditions: 3.5ul H₂, 1ul Primers, 0.5ul template, 5ul taq
• Running conditions: 95C 10min, 95C 30sec, 48C 30sec, 68C 10 min, 68C 10min, 4C infinity.

• Green Taq:

• Reaction conditions: 3.5ul H₂, 1ul Primers, 0.5ul template, 5ul taq
• Running conditions: 95C 10min, 95C 30sec, 48C 30sec, 68C 10 min, 68C 10min, 4C infinity.

• Velocity DNA Polymerase:

• Reaction conditions: 2ul 5X Buffer, 0.1ul dNTPs, 5.65ul H₂O, 1ul Primers, 0.5ul template, 0.25ul taq(0.5U)
• Running conditions: 98C 2min, 98C 30sec, 48C 30sec, 72C 2min34sec, 72C 10min, 4C infinity.

Results

• As seen in the very small picture, the only amplification product of this reaction is of the positive control amplified by green taq.
• The omega interposon template (pSMC121) was run on a gel alongside the products of the colony PCR from 7_21. There was no band meaning that there was no template for this PCR reaction.

Discussion

• Need to get in touch with Dr. Callahan and get more template. Also, just try again with green taq only... problem solve.

7/23

• PCR amplification of the omega interposon region of pSMC121 and the mob/rep region of pRL1383a using green taq.
• Reaction conditions: same as above
• Running conditions: same as above for green taq.

Results

PCR amplification of mob/rep region and omega interposon. Lane 1: 2-log tridye ladder, lane 2:omega interposon, lane 3: mob/rep region, lane 4: negative control, lane 5: positive contol.

• The omega interposon amplification yielded only primer dimers. The mob/rep region is a smear, there is a lot of mis-priming. The positive and negative controls yield a bright band and no band respectively.

Discussion

• the omega interposon primers are likely to form dimers because there are 4 overlapping nucleotides at the 5' and 3' ends with a Gibbs free energy of -6.61 kcal/mole. I can alleviate this problem by finding a higher annealing temperature than 48°C. The annealing temperature is 49.5°, so I can use a gradient to find a good temperature. I will try from 48deg&;C to 55°C.

• The above stated method for solving the primer dimer problem can also be a possible solution for the mis-priming of the mob/rep region.

PCR Products

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