Polynucleotide kinase from a T4 mutant which lacks the 3' phosphatase activity.
Polynucleotide kinase from E. coli infected with the PseT 1 mutant of bacteriophage T4 has been isolated. The PseT 1 enzyme purifies similarly to normal polynucleotide kinase and effectively transfers the gamma phosphate of ATP to the 5' terminal hydroxyl of DNA and RNA. The PseT 1 and normal enzymes require similar magnesium ion concentrations, have the same pH optima and are both inhibited by inorganic phosphate. However, the PseT 1 enzyme is totally lacking the 3' phosphatase activity associated with normal  polynucleotide kinase. The PseT 1 enzyme is a useful tool for the preparation of oligonucleotides with 3' and 5' terminal phosphates for use as susbstrates for RNA ligase.
D003090:Coliphages / Q000201:enzymology* / Q000235:genetics; D009154:Mutation; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism*; D011116:Polynucleotide 5'-Hydroxyl-Kinase / Q000235:genetics / Q000378:metabolism*
D010770:Phosphotransferases; D011116:Polynucleotide 5'-Hydroxyl-Kinase; D010744:Phosphoric Monoester Hydrolases