T7 DNA Polymerase (3500 U)

A highly processive, mesophilic replicative DNA polymerase from bacteriophage T7, offered by QIAGEN, that is responsible for the rapid and accurate replication of the virus' genome. The enzyme is a two-subunit protein consisting of a polymerase domain (gene 5 from bacteriophage T7) and a processivity factor (E. coli trxA gene thioredoxin). It possesses a powerful (3′→5′) exonuclease activity that acts on both single- and double-stranded DNA, contributing to its high fidelity and preventing strand-displacement synthesis.

Quality control specifications include purity >99%, specific activity 13,333 U/mg, functional single-stranded and double-stranded exonuclease activities, no conversion in double-stranded endonuclease assays at 100 U, and <10 copies of E. coli DNA contamination at 100 U. The recombinant protein is produced in E. coli strains carrying the bacteriophage T7 gene 5 and E. coli trxA gene, with a molecular weight of 92.1 kDa. One unit is defined as the amount of polymerase required to convert 10 nmol of total dNTPs into acid-insoluble material in 30 minutes at 37°C. The enzyme is supplied at a concentration of 10,000 U/mL in 50 mM KPO4, 1 mM DTT, 0.1 mM EDTA and 50% glycerol (pH 7.0 at 25°C), and ships with a 10X T7 DNA Polymerase Buffer containing 400 mM Tris-HCl, 200 mM MgCl2 and 500 mM NaCl (pH 7.5 at 25°C). Storage temperature is -25°C to -15°C.

The product is intended for in vitro use only and is suitable for applications such as second-strand synthesis following first-strand synthesis off an RNA template, or site-directed mutagenesis where a mutagenic primer is extended to copy the entire template strand. Standard reaction conditions include a 60-minute incubation at 37°C followed by 10 minutes at 70°C to stop the reaction. Note: this enzyme is not suitable for DNA sequencing.