I have a plasmid. This plasmid has 2 promoters, the first one is T7P to express araC protein. And the second promoter is pBAD to express lacZ protein. Both promoters are on the same plasmid and in the same direction. What I want is to do a PCR reaction to make them express the 2 proteins in the opposite direction. How to do that?
Why not have them in the same direction? If you have promoter, RBS and terminator, it should work fine. You have other expression units on your plasmid anyway (resistance gene, if nothing else).
If you want to switch one of the promoters anyway (but remember that you need to include the other parts - where you clone your GOI and terminator), you can amplify that piece and your plasmid and clone it back through one of many homology-based methods. Or, if you prefer digestion-ligation cloning, just design primers both for your plasmid and your "insert" with appropriate restriction sites, then digest and ligate.
Directionality is arbitrary, as in someone decided which strand was template vs coding when they designed the plasmid. Why do you think you want to change it?
If you put a promotor to express the reverse complement of a protein-coding gene, then you will get an entirely different sequence of amino acids (and most likely a premature stop codon).
What exactly is your project? No reputable journals will publish "I flipped over a known region of a known plasmid" unless it's proof-of-principle for something much more complicated & novel.
Have you talked with your advisor?
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