What are the limitations of Taq polymerase?

Posted June 22, 2020

DNA and RNA Quantitation

Polymerase Chain Reaction (PCR)

Real-Time PCR (qPCR)

Answer

Despite the extensive application of Taq polymerase in PCR reaction, this enzyme still has some limitations.

Low specificity: Taq DNA polymerase has a lower specificity than the normal ones. Mismatches nucleotides could be added to the sequence by Taq polymerase.
Low fidelity: Taq polymerase does not have 3’ to 5’ exonuclease proofreading activity, therefore mismatches nucleotides could not be corrected.
Bivalent cation requirement: Taq polymerase requires cofactors, such as Mg2+ ion, to work properly.

Additional resources

6-ROX glycine *25 uM fluorescence reference solution for PCR reactions*

Chen, S. C., Halliday, C. L., & Meyer, W. (2002). A review of nucleic acid-based diagnostic tests for systemic mycoses with an emphasis on polymerase chain reaction-based assays. Medical mycology, 40(4), 333-357.

Chuang, L. Y., Cheng, Y. H., & Yang, C. H. (2013). Specific primer design for the polymerase chain reaction. Biotechnology letters, 35(10), 1541-1549.

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