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will the template of PCR be added A ? - (Mar/19/2012 )

When I use Taq polymerase for PCR, the end of product sequence will be added "A" by Taq ploymerase.

Now I have a question.

My template is about 800 bp. I will want to use PCR product to do TA cloning.

When I use Taq polymerase for PCR, will the template of PCR reaction be added A ?

Because my friend said it that would be added A to the end of template sequence of PCR reaction.

If my friend is right.

I maybe will construct template to TA cloning.

Colud anyone can tell me?


when you use Taq polymerase adenine will automatically be added to both 3' ends of your PCR product, no matter what template DNA you use. But the chance of getting A depends on having G and T on the 5' end of your PCR primers too. I can't give you any reference. look up by yourself on Google. However, I never had this problem, and I always ended up with overhang A.

Just don't use Pfu or Pfx polymerase.


Thanks Curtis