Procedure
Design Primers:
These primers are like bridges between the two parts you want to assemble together.
You will order two primers which are complements of one another.
These primers will each have a 60°C Tm with one part and a 60°C Tm with the other part.
The "end primers" will not have any complements and will likely only have restriction sites.
"Extension PCR" PCR amplify the necessary fragments separately
Use a proofreading polymerase enzyme.
Use an annealing temp of 60°C.
Clean up the product using a DNA column.
"Overlap PCR" Use cleaned up fragments as template in a PCR reaction:
About 1/2 to 3/4 volume of the Overlap PCR reaction should be equimolar amounts of purified fragments.
Do not use Phusion polymerase. Try Pfu Turbo.
Do not add any primers; the templates will prime each-other.
Run 15 PCR cycles without primers.
Use an annealing temp of 60°C.
"Purification PCR" Add end primers to the Overlap PCR reaction:
Continue cycling for another 15-20 rounds.
Use an annealing temp of 72°C
Gel extract the correct size fragment.
Clone into the desired vector.
Digest
Ligate
Transform
Select
Sequence