Thermostable DNA polymerase, suitable for applications requiring high temperature synthesis of DNA. The enzyme replicates DNA at 74°C and exhibits a half-life of 40 min at 95°C. Catalyzes the polymerization of nucleotides into duplex DNA in the 5´→3´ direction in the presence of magnesium ions. Maintains the 5´->3´ exonuclease activity. Lacks the 3´→5´ exonuclease activity. Adds extra A at the 3′ ends. Taq DNA Polymerase is recommended for use in PCR and primer extension reactions at elevated temperatures to obtain a wide range of DNA products up to 10 kb.