T4 Polynucleotide Kinase (T4 PNK)

Versatile End-Modification Enzyme for NGS, Probe Labeling & Molecular Cloning

3 activities

5′ kinase, phosphatase / exchange, 3′ phosphatase

End repair

FFPE and cfDNA fragment ends

T4 Polynucleotide Kinase (T4 PNK), BR3P303 product image

Product overview

T4 Polynucleotide Kinase (T4 PNK) is a versatile polynucleotide 5′-hydroxyl kinase that catalyzes precise end modifications of DNA, RNA, and nucleotide substrates. It is an essential reagent for workflows requiring controlled nucleic acid terminal functionalization, including NGS library preparation, probe labeling, and ligation-dependent molecular biology applications.

Features and applications

Features

Triple End-Modification Activity: Delivers three functionally distinct, workflow-relevant activities:
- Forward 5′-hydroxyl kinase activity: Transfers the γ-phosphate group from ATP to the 5′-OH terminus of double-stranded DNA (dsDNA), single-stranded DNA (ssDNA), RNA, and nucleoside 3′-monophosphates.
- 5′-Phosphatase/exchange activity: In the presence of ADP, removes 5′-terminal phosphates and catalyzes phosphate exchange between 5′-phosphorylated oligo-/polynucleotides and ATP.
- 3′-Phosphatase activity: Hydrolytically removes 3′-phosphate groups from DNA, RNA, and deoxynucleoside 3′-monophosphate termini, repairing damaged nucleic acid ends that are incompatible with ligation.
Broad Substrate Compatibility: Functions efficiently with dsDNA, ssDNA, RNA, and nucleotide monophosphates, supporting diverse experimental designs.
High Reaction Efficiency: Achieves rapid, complete end modification under standard reaction conditions, minimizing protocol optimization time.
Ultra-High Purity: Rigorously batch-tested to confirm the absence of detectable DNase, RNase, and non-specific nuclease contamination, ensuring reproducible results for sensitive applications.

Applications

NGS Library Preparation: 5′-phosphorylation of DNA fragments and adapters to enable efficient ligation; 3′-phosphate removal to repair damaged ends from FFPE, cfDNA, or chemically treated samples, reducing ligation failures and improving library yield.
Nucleic Acid Probe Labeling: 5′-end labeling with radioactive, fluorescent, or biotin tags via forward kinase activity; site-specific probe modification via phosphate exchange reactions.
Molecular Cloning: Preparation of phosphorylated linkers, vector arms, and RNA termini for ligation-dependent workflows.
Diagnostic R&D: Development of hybridization-based or ligation-dependent molecular detection assays requiring precise nucleic acid end modification.

Components

Component	Specification/Notes
T4 Polynucleotide Kinase	10 U/μL
10×T4 PNK Buffer	10×

Performance data

Equivalent 3′ Dephosphorylation Activity to Supplier N

BR3P303 T4 Polynucleotide Kinase (T4 PNK): 3′ dephosphorylation activity, reaction scheme — **Figure 1. Equivalent 3′ dephosphorylation activity to Supplier N.** BR3P303 (T4 PNK) and Supplier N’s single-enzyme T4 PNK product were evaluated at equal enzyme concentrations. Lower Ct values indicate more complete 3′ dephosphorylation of damaged nucleic acid termini. BR3P303 showed matching Ct values to Supplier N, confirming comparable enzymatic activity and reliable performance for NGS library preparation, particularly for FFPE, cfDNA, and other damaged sample types where 3′ end repair is critical for ligation efficiency.

Note: BR3P303 is the catalog number for this product. 3′ end repair is a prerequisite for library construction from damaged samples, as it restores ligation compatibility of termini compromised by nucleic acid degradation, preventing low library yields.