T7 RNA Polymerase
T7 RNA Polymerase
T7 RNA Polymerase is a DNA-dependent RNA polymerase that exhibits a high specificity for bacteriophage T7 promoter sequences. The enzyme can incorporate labeled or unlabeled nucleotide triphosphates into an RNA transcript. Large quantities of RNA can be synthesized from a DNA sequence cloned downstream from a T7 promoter. T7 RNA Polymerase is supplied in 20 mM potassium phosphate (pH 7.9), 100 mM NaCl, 1 mM DTT, 0.1 mM EDTA and 50% glycerol.
Applications
- In vitro transcription
Source
Recombinant E. coli
Storage
–20°C
Unit definition
One unit is defined as the amount of enzyme required to convert 1 nmol of [3H] GMP into acid-insoluble product in 1 hour at 37°C and pH 8.0 using linear DNA as the substrate.
Buffer
Supplied with 10X Reaction Buffer [400 mM Tris-HCl (pH 8.0), 80 mM MgCl2, 20 mM spermidine, and 50 mM DTT].
Concentration
10–50 U/µl
Chamberlin, M., McGrath, J. & Waskell, L. New RNA polymerase from Escherichia coli infected with bacteriophage T7. Nature 228, 227–31 (1970).
Chamberlin, M. & Ring, J. Characterization of T7-specific ribonucleic acid polymerase. 1. General properties of the enzymatic reaction and the template specificity of the enzyme. J. Biol. Chem. 248, 2235–44 (1973).
Davanloo, P., Rosenberg, A. H., Dunn, J. J. & Studier, F. W. Cloning and expression of the gene for bacteriophage T7 RNA polymerase. Proc. Natl. Acad. Sci. U. S. A. 81, 2035–9 (1984).
Schenborn, E. T. & Mierendorf, R. C. A novel transcription property of SP6 and T7 RNA polymerases: dependence on template structure. Nucleic Acids Res. 13, 6223–36 (1985).