DNA Polymerase I is a DNA polymerase with 5´-3´ and 3´-5´ exodeoxyribonuclease activities. DNA Polymerase I incorporates biotinylated nucleotides.

Applications:DNase I-dependent nick translation (1,2). Second-strand synthesis in cDNA cloning (3). Fill-in of 5´ overhang (4).

Source: Purified from E. coli expressing the DNA Polymerase I gene on a plasmid.

Performance and Quality Testing: Endodeoxyribonuclease assay; efficiency of DNase I-dependent nick translation determined.

Unit Definition: One unit incorporates 10 nmol of total deoxyribonucleotide into acid-precipitable material in 30 min. at 37°C using templateprimer.

Unit Reaction Conditions: 50 mM potassium phosphate (pH 7.0), 6.7 mM MgCl₂ , 1 mM 2-mercaptoethanol, 80 µg/ml templateprimer, 32 µM dTTP, 69 nM [³H]dTTP, and enzyme in 100 µl for 30 min. at 37°C.