Klenow Fragment, exo– (5 U/μL)
Inquire about OEM or Commercial Supply version of this product here.
Klenow Fragment, exo– (5 U/μL)
Thermo Scientific™

Klenow Fragment, exo– (5 U/μL)

Thermo Scientific Klenow Fragment, exo-, is the large fragment of DNA polymerase I . It exhibits 5'→3' polymerase activity, butRead more
Have Questions?
Change viewbuttonViewtableView
Catalog NumberQuantity
EP0421300 U
EP04221500 U
Catalog number EP0421
Price (USD)
153.00
Each
Add to cart
Quantity:
300 U
Request bulk or custom format
Price (USD)
153.00
Each
Add to cart
Thermo Scientific Klenow Fragment, exo-, is the large fragment of DNA polymerase I . It exhibits 5'→3' polymerase activity, but lacks the 3'→5' and 5'→3' exonuclease activities of DNA Polymerase I. The 3'→5' exonuclease activity of the enzyme is eliminated by mutations in the 3'→5'-exonuclease active site.

Highlights

• Lacks 3'→5' exonuclease activity
• Incorporates modified nucleotides (e.g., Cy3-, Cy5-, fluorescein-, rhodamine-, aminoallyl-, biotin-labeled nucleotides)
• Active in restriction enzyme, PCR, and RT buffers

Applications
• Random-primed DNA labeling
• Labeling by fill-in 5'-overhangs of dsDNA
• Strand displacement amplification (SDA)
• DNA sequencing by the Sanger method

Note

Klenow Fragment, exo- is not recommended for DNA blunting reactions prior to DNA ligation since it frequently adds one or more extra nucleotides to the 3'-terminus of blunt-end DNA substrates in a non-template directed fashion.
For Research Use Only. Not for use in diagnostic procedures.
Specifications
Concentration5 U/μL
PolymeraseDNA Polymerase I
Compatible BufferRestriction Enzyme, PCR, RT Buffer
Quantity300 U
Product TypeKlenow Fragment
Unit SizeEach

Frequently asked questions (FAQs)

What are the differences between Thermo Scientific DNA Polymerase I, Klenow Fragment, and Klenow Fragment (exo-)?

Thermo Scientific DNA Polymerase I possesses 5′?3′ DNA synthesis activity, 3′?5′ exonuclease (proofreading) activity, and 5′?3′ exonuclease activity. Klenow Fragment is the large fragment of DNA polymerase I. It exhibits 5′?3′ polymerase activity and 3′?5′ exonuclease (proofreading) activity, but lacks 5′?3′ exonuclease activity. Klenow Fragment, exo-, is also the large fragment of DNA polymerase I. It exhibits 5′?3′ polymerase activity, but lacks the 3′?5′ and 5′?3′ exonuclease activities.

What conditions are optimal for fill-in reactions using Klenow (Large fragment of DNA Polymerase)?

Klenow can be used to "fill in" 5' overhangs of double-stranded DNA fragments using common restriction endonuclease buffers. We recommend REact 2 buffer (1X concentration is 50 mM Tris-HCl pH 8, 50 mM NaCl, 10 mM MgCl2) , but other buffers will also work.

Fill-in Reaction Conditions:

1. Dilute Large Fragment of DNA Polymerase I to 0.5 U/µL with Klenow Dilution Buffer.
2. To a 1.5-mL microcentrifuge tube on ice, add: 10X REact 2 Buffer - 3 µL, 0.5 mM dATP - 1 µL, 0.5 mM dCTP - 1 µL, 0.5 mM dGTP - 1 µL, 0.5 mM dTTP - 1 µL, DNA 0.5-1 µg, Large fragment of DNA Polymerase I - 1 µL, Autoclaved distilled water to 30 µL.
3. Mix gently and centrifuge briefly to bring the contents to the bottom of the tube.
4. Incubate at room temperature for 10-15 minutes or 20 minutes on ice.
5. Terminate fill-in reaction by phenol extraction.

To label the DNA fragment, use 1-2 µL of [alpha-32P]dNTP (400 Ci/mmol, 10 mCi/mL) (24-48 pmoles) instead of the corresponding cold dNTP.

Note: Thermo Fisher Scientific also offers an Exo minus Klenow, which is provided with its own buffers.