In the laboratory setting, Pfu is used to amplify DNA in the polymerase chain reaction (PCR), where the enzyme serves the central function of copying a new strand of DNA during each extension step.
Unlike Taq DNA polymerase, Pfu DNA polymerase possesses 3' to 5' exonuclease proofreading activity, meaning that as the DNA is assembled from the 5' end to 3' end, the exonuclease activity immediately removes nucleotides misincorporated at the 3' end of the growing DNA strand.
Commercially available Pfu typically results in an error rate of 1 in 1.3 million base pairs and can yield 2.6% mutated products when amplifying 1 kb fragments using PCR.
However, Pfu is slower and typically requires 1–2 minutes per cycle to amplify 1kb of DNA at 72 °C.
[3] Scientists led by Eric Mathur at the biotech company Stratagene, based in La Jolla, California, discovered Pfu DNA polymerase which exhibits significantly higher fidelity of replication than Taq DNA polymerase in 1991.