DNA Polymerase I

DNA Polymerase I, also known as Pol I, was initially isolated from E. coli and was the first polymerase to be extensively studied. Encoded by the gene polA, the 928-amino acid enzyme has several activities: A 5’-3’ polymerase activity, 5’-3’ exonuclease activity, and a 3’-5’ exonuclease activity. A recombinant truncated version of DNA polymerase I that does not contain the 5’-3’ exonuclease activity is also called the Klenow fragment. DNA Pol I has found use in DNA modification applications such as in nick translation with DNase and second-strand synthesis of cDNA. Visit the DNA polymerase I supplier page for more information on this useful molecular tool.