T4 Polynucleotide Kinase 500 units

This enzyme catalyzes the transfer of the terminal phosphate group of ATP to 5'-OH ends of DNA.

T4 polynucleotide Kinase catalyses the transfer of P from the gamma position of ATP to 5' hydroxyl termini of polynucleotides (DNA and RNA) as well as to nucleoside 3'-monophosphates. It is used for endlabeling of DNA and RNA and DNA sequencing, as well as for phosphorylation of 5'-hydroxyl DNA fragments to allow subsequent ligation. For complete nonradioactive phosphorylation of 5'-hydroxyl ends more than a twofold molar excess of ATP should be used with a minimum concentration of 100 µM. T4 polynucleotide kinase activity is very sensitive to the addition of salts: 150 mM NaCl will give rise to a 50% inhibition. Since 10 mM (NH4)2SO4 will inhibit the enzyme by more than 80% it is not recommended to precipitate DNA before phosphorylation.