Tsg DNA Polymerase is a thermostable DNA Polymerase isolated from a strain of Thermus sp. Tsg has a half life of 3 hours at 95 oC, it is therefore more stable than Taq DNA Polymerase. Tsg has high fidelity with an error frequency 10 / 106 ( or 0.01 / 103 ) during DNA synthesis. Taq is designed for use in primer extension reaction. Tsg can also be used for sequencing. DNA sequencing at high temperature may decrease the second structure of some DNA templates and permit polymerization through base-paired region. DNA sequencing with Tsg DNA Polymerase produces uniform bands intensities and low background.

Tsg DNA Polymerase is highly purified free of contaminating endonucleases, exonucleases and nicking activity. For endonuclease assay, 1 ug of Lambda / Hind III DNA is incubated with 20 units of the enzyme in assay buffer at 750 C for 16 hrs and no visible contaminating activity is observed; For exonucleases assay, 1 ug of pBR322 plasmid DNA is incubated with 10 units of enzyme for 16 hrs at 75oC in assay buffer and no detectable exonuclease is observed. The purity of the enzyme is also evaluated by adding 10 units of Tsg DNA Polymerase in 100 ul of a reaction mixture for making first strand cDNA at beginning and no impaired effect on the first strand is observed.