Klenow Fragment (3´→5´ exo-) NEB

DNA polymerases are indispensable tools in molecular biology and biotechnology. Among them, the Klenow Fragment (3’→5’ exo-) from NEB is one of the most widely used enzymes for DNA research. This exonuclease-deficient DNA polymerase is optimized for applications requiring precise DNA synthesis, labeling, and amplification. Researchers in genomics, molecular diagnostics, and biotechnology rely on this enzyme for its high fidelity, efficiency, and versatility in DNA manipulation.

What is the Klenow Fragment (3’→5’ exo-)?

The Klenow Fragment is a large proteolytic fragment of DNA Polymerase I from E. coli. The exo- version is engineered to lack the 3’→5’ exonuclease activity, meaning it cannot degrade DNA from the 3’ end. This modification makes it ideal for experiments requiring accurate DNA synthesis without unwanted degradation of DNA templates.

Key Features

• High-fidelity DNA polymerase with reduced error rates
• 3’→5’ exonuclease-deficient, preventing template degradation
• Efficient in DNA labeling and end-filling reactions
• Optimized for PCR, cDNA synthesis, and cloning workflows

Applications of Klenow Fragment (3’→5’ exo-)

1. Next-Generation Sequencing (NGS) Library Preparation

The Klenow Fragment (exo-) plays a critical role in NGS workflows, especially during end-repair and adapter ligation steps. Its ability to fill in DNA overhangs ensures precise and uniform library construction.

2. DNA Repair and End-Filling

In DNA repair studies, this enzyme is used to fill recessed 3’ ends, making it invaluable for repairing damaged DNA in both experimental and clinical research.

3. cDNA Synthesis

For researchers working with RNA-to-DNA conversion, Klenow Fragment supports second-strand cDNA synthesis, ensuring high-quality complementary DNA for downstream applications.

4. DNA Labeling and Probes

Its efficiency in incorporating labeled nucleotides makes it a reliable choice for radioactive or fluorescent probe preparation, widely used in hybridization assays and molecular diagnostics.

5. Cloning and Genome Editing

In cloning workflows, Klenow Fragment (exo-) provides accurate DNA replication and modification, supporting synthetic biology and CRISPR-based genome editing projects.

Advantages of Using NEB Klenow Fragment (3’→5’ exo-)

• Reliable performance across a wide range of DNA substrates
• High accuracy in DNA amplification and labeling
• Compatible with multiple protocols, including PCR and sequencing
• Trusted by researchers worldwide for molecular biology and genomics

Conclusion

The Klenow Fragment (3’→5’ exo-) NEB is an essential enzyme for laboratories focused on DNA research, genomics, and biotechnology applications. With its ability to perform precise DNA synthesis, labeling, and repair, this DNA polymerase remains a cornerstone in next-generation sequencing, cloning, and molecular diagnostics.

Whether for academic research or clinical development, the Klenow Fragment (exo-) provides the reliability and high performance scientists need to advance their DNA-based discoveries.