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A Single Amino Acid Change to Taq DNA Polymerase Enables Faster PCR, Reverse Transcription and Strand-Displacement.

ABSTRACT: A change of an aspartic acid to asparagine of Taq (Thermus aquaticus) DNA polymerase is a gain of function mutation that supports faster PCR: the extension times for PCR amplification can be 2-3 times shorter. Surprising results from negative controls led to the discovery of strand-displacement ability and reverse transcriptase activity of Taq D732N DNA polymerase. We demonstrate that the mutant enzyme can, by itself, catalyze RT-PCR, and RT-LAMP assays. Residue 732 is on the surface of the enzyme, not near the active site.

SUBMITTER: Barnes WM

PROVIDER: S-EPMC7841393 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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A Single Amino Acid Change to Taq DNA Polymerase Enables Faster PCR, Reverse Transcription and Strand-Displacement.

Barnes Wayne M WM Zhang Zhian Z Kermekchiev Milko B MB

Frontiers in bioengineering and biotechnology 20210114

A change of an aspartic acid to asparagine of Taq (<i>Thermus aquaticus</i>) DNA polymerase is a gain of function mutation that supports faster PCR: the extension times for PCR amplification can be 2-3 times shorter. Surprising results from negative controls led to the discovery of strand-displacement ability and reverse transcriptase activity of Taq D732N DNA polymerase. We demonstrate that the mutant enzyme can, by itself, catalyze RT-PCR, and RT-LAMP assays. Residue 732 is on the surface of t ...[more]

PMID: 33520948

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