T4 DNA POLYMERASE 250 UN，18005025，Invitrogen

T4 DNA Polymerase is a DNA polymerase that has a 3´-exodeoxyribonuclease activity, but lacks 5´a3´ exodeoxyribonuclease activity. A T4 DNA Polymerase Technical Bulletin is available.

Applications: Labeling double-stranded linear DNA by replacement synthesis (1). Oligonucleotide-directed, site-specific mutagenesis (2). 3´ end-labeling of double-stranded DNA (3). Polishing both 5´ or 3 overhangs to make blunt ends (4).

Source: Purified from E. coli expressing the T4 DNA Polymerase gene on a plasmid.

Performance and Quality Testing: Single- and double-stranded endodeoxyribonuclease and phosphatase assays; exodeoxyribonuclease and polymerase activities tested.

Unit Definition: One unit incorporates 10 nmol of total deoxyribonucleotide into acid-precipitable material in 30 min. at 37°C using DNase I-nicked DNA as template•primer.

Unit Reaction Conditions: 50 mM glycine-NaOH (pH 8.8), 16.6 mM (NH₄)₂SO₄ , 6 mM MgCl₂ , 6.5 µM EDTA, 10 mM 2-mercaptoethanol, 0.165 mg/ml BSA, 1.6 mg/ml DNase I-nicked salmon testes DNA, 0.33 mM dCTP, 0.33 mM dATP, 0.33 mM dGTP, 0.33 mM dTTP, 76 nM [³H]dTTP, and enzyme in 0.1 ml for 30 min. at 37°C.