DNA Polymerase I, Large (Klenow) Fragment

Type of Enzyme

DNA Polymerase

Applications

DNA Assembly

In the Public Domain since

June 7, 2023

Application Features

Retains 5′ → 3′ polymerase activity and the 3’ → 5’ exonuclease activity for removal of precoding nucleotides and proofreading, but loses its 5′ → 3′ exonuclease activity.
Applications:
Synthesis of double-stranded DNA from single-stranded templates
Filling in receded 3′ ends of DNA fragments to make 5′ overhang blunt
Digesting away protruding 3′ overhangs
Preparation of radioactive DNA probes

Original Paper

Klenow, H., & Henningsen, I. (1970). Selective elimination of the exonuclease activity of the deoxyribonucleic acid polymerase from Escherichia coli B by limited proteolysis. Proceedings of the National Academy of Sciences, 65(1), 168-175.

Joyce, C.M. and Grindley, N.D., 1983. Construction of a plasmid that overproduces the large proteolytic fragment (Klenow fragment) of DNA polymerase I of Escherichia coli. Proceedings of the National Academy of Sciences, 80(7), pp.1830-1834. https://doi.org/10.1073/pnas.80.7.1830

Ollis, D.L., Brick, P., Hamlin, R., Xuong, N.G. and Steitz, T.A., 1985. Structure of large fragment of Escherichia coli DNA polymerase I complexed with dTMP. nature, 313(6005), p.762.