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Phusion U Hot Start DNA Polymerase

Catalog number: F555S

Thermo Scientific™  Related applications: PCR

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Thermo Scientific Phusion U DNA polymerase is a novel engineered high fidelity enzyme developed using fusion technology. Due to a proprietary mutation in the so called dUTP binding pocket of Phusion, Phusion U overcomes an important limitation of proofreading enzymes - it is able to incorporate dUTP and read through uracil present in DNA templates.

In addition to uracil usage possibility, Phusion U features all the superior properties of other Phusion DNA Polymerases - great accuracy, speed, ability to amplify long amplicons up to 20 kb and a high specificity with Affibody based hot start. These features make Phusion U Hot Start DNA Polymerase an excellent choice for such important applications as amplification of bisulphite-converted or damaged DNA as well as use of carryover contamination control.

Phusion U Hot Start DNA Polymerase is also available in the Master Mix and Green formats. Phusion U Hot Start PCR Master Mix (F-533S and F-533L) is convenient 2X mix designed to minimize the number of pipetting steps. Only template and primers need to be added by the user. Phusion U Green format (F-556S and F-556L) is a combination of Phusion U Hot Start DNA Polymerase and 5X Phusion Green Buffers. The buffers include a density reagent and two tracking dyes for direct loading of PCR products on a gel. The colored buffer does not interfere with Phusion U performance and is compatible with downstream applications such as DNA sequencing, ligation and restriction digestion.


Accuracy—high fidelity DNA polymerase (25x Taq)
Uracil-tolerance —engineered to incorporate dUTP and amplify uracil containing templates
Specificity—hot start for reduced nonspecific amplification and primer degradation
Speed —short extension times (15-30 s/kb)


• Amplification of bisulphite-converted DNA
• Amplification of damaged or aged DNA
• Carry-over contamination control
• Uracil-excision based (USER) cloning methods
For Research Use Only. Not for use in diagnostic procedures.


Polymerase: Phusion U Hot Start DNA Polymerase
Hot Start: Built-In Hot Start
Fidelity (vs. Taq): 25 X
GC-Rich PCR Performance: High
Reaction Format: Standalone
Product Overhang: Blunt
Reaction Speed: Fast
Product Line: Phusion
Product Size: 100 units

Contents & storage

• Phusion U Hot Start DNA Polymerase, 2 U/µL
• 5X Phusion HF Buffer
• 5X Phusion GC Buffer
Both Phusion HF Buffer and Phusion GC Buffer provide 1.5 mM MgCl2 in the final 1X concentration.

Store at -20°C.


Manuals & protocols

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