Pfu DNA Polymerase is a thermostable protein isolated and purified from recombinant E.coli strains containing Pyrococcus furiosus DNA Polymerase gene, with a molecular weight of about 90KD. With 5'→3' polymerase activity and 3'→5' exonuclease activity, it can remove mismatched bases inserted during extension.Pfu DNA Polymerase is the one with the highest fidelity among the heat-resistant DNA polymerases found so far. The PCR product is blunt-ended and can be directly linked to the blunt-ended cloning vector, or the end is treated with A and then connected to the TA vector.