What is Taq DNA Polymerase?

Taq DNA Polymerase is a thermostable DNA Polymerase that catalyzes 5’→3′ DNA synthesis. Taq DNA Polymerase has 5’→3′ exonuclease activity and is deficient in 3’→5′ exonuclease activity. Taq DNA polymerase amplifies uracil-containing templates, can incorporate modified bases, and performs A-tailing on DNA products. This enzyme is provided in a non-hot start format.

What is the unit definition of Taq DNA Polymerase?

One unit of Taq DNA polymerase is the amount of enzyme that will incorporate 10 nmol of dNTP into activated calf thymus DNA in 30 minutes at 75°C.

What are the applications for Taq DNA Polymerase?
  • Probe and intercalating dye-based qPCR
  • RT-qPCR
  • dA tailing of DNA substrates pre-ligation
  • PCR amplification of DNA fragments (≤ 5 kb)
  • Homebrew NGS library prep
What is the storage buffer for Taq DNA Polymerase?
  • 20 mM Tris-HCl, pH 7.4
  • 100 mM NaCl
  • 1 mM DTT
  • 0.1 mM EDTA
  • 50% Glycerol
  • 0.5% Tween 20
What buffer is the recommended reaction buffer for Taq DNA Polymerase?

Taq DNA Polymerase performs well in a range of buffers. The recommended 10X buffer composition is a standard PCR buffer. This buffer can be optimized for specific applications.

Standard 10X reaction buffer (not supplied with kit): 200 mM Tris-HCl, pH 8.3, 400 mM KCl

What are the recommended reaction setup conditions?

Please reference our technical guide for instructions for use.

On ice, combine components as specified:

Component Final Concentration Volume
(25 µL reaction)
Buffer (10X) 1X 2.5 µL
MgCl₂ (25 mM) Variable* Variable*
Each primer 10 µM (Fwd/Rev) 0.2 µM 0.5 µL
Taq DNA Polymerase
(5 U/µL)
Variable** Variable**
dNTPs (10 mM each) 0.2 mM 0.5 µL
Template DNA Variable Variable
PCR grade water Up to 25 µL

* 2mM is the suggested final MgCl₂ concentration. Mg2+ concentrations can alter reaction performance and may need to be optimized. A scouting range between 1 – 6 mM MgCl₂ is recommended. Probe based applications will benefit from increased MgCl₂ concentration.

** Optimizing the enzyme concentration is recommended. A good general purpose starting point is 0.071 U/µL. Use higher concentrations of polymerase, up to 1.44 U/µL, in reactions with high concentrations of inhibitors, for fast PCR, or when no amplification is observed. Use lower concentrations of polymerase if non-specific amplification is observed.

Can Taq DNA polymerase be used for 1-step qRT-PCR?

Yes, but reverse-transcriptases are usually inhibitory to PCR enzymes and 1-step qRT-PCR assays may benefit from adding higher concentrations of polymerase.

Are protected primers required for Taq-based PCR amplification?

No, Taq 5’→3′ endonuclease activity targets double stranded DNA and as such will not degrade primers.

Can Taq DNA polymerase be used for nick translation?

Yes they are compatible, but DNA Polymerase I is preferred.

Is there a recommended size limit for primer extension using Taq DNA polymerase?

Yes, it is generally not recommended to use Taq DNA polymerase for primer extensions longer than 5 kb, or templates with extensive secondary structure.

Does Taq create dA overhang from PCR?

Yes, this overhang can be used to ligate adapters with a T-overhang.

How can I maximize the yield from Taq DNA polymerase?
  • Use templates shorter than 5 kb
  • Optimize annealing temperature of the primers
  • Use at least 0.2 μM final concentration of each primer
  • Add fresh nucleotides
  • For GC-rich templates, add DMSO to lower the temperature. Alternatively, Equinox Polymerase Master Mix can be used for more challenging targets
What is the extinction coefficient for Taq DNA Polymerase?

The extinction coefficient for Taq DNA Polymerase is 1.201 (mL/(mg*cm). If measuring protein concentration (A280), we recommend you use the protein’s extinction coefficient to ensure an accurate reading.

Do you offer custom formats?

Yes! Watchmaker offers customer fills, packaging, concentrations, and labeling – including private label – designed to meet your unique needs. We offer flexible terms to serve organizations of any size, and our right-sized processes enable rapid turnaround time on customization. Please contact sales@watchmakergenomics.com to learn more about our capabilities.

Are you ISO 13485-certified?

Yes! Our Quality Management System has achieved ISO 13485:2016 Certification. Our certificate has been awarded for the design, development, manufacture, contract manufacture, and support of high performing reagents for genomics applications in medical research. Download the certificate here.