Polynucleotide 5'-hydroxyl-kinase

In enzymology, a polynucleotide 5'-hydroxyl-kinase is an enzyme that catalyzes the chemical reaction


 * ATP + 5'-dephospho-DNA $$\rightleftharpoons$$ ADP + 5'-phospho-DNA

Thus, the two substrates of this enzyme are ATP and 5'-dephospho-DNA, whereas its two products are ADP and 5'-phospho-DNA.

This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The systematic name of this enzyme class is ATP:5'-dephosphopolynucleotide 5'-phosphotransferase. Other names in common use include ATP:5'-dephosphopolynucleotide 5'-phosphatase, PNK, polynucleotide 5'-hydroxyl kinase (phosphorylating), 5'-hydroxyl polynucleotide kinase, 5'-hydroxyl polyribonucleotide kinase, 5'-hydroxyl RNA kinase, DNA 5'-hydroxyl kinase, DNA kinase, polynucleotide kinase, and polynucleotide 5'-hydroxy-kinase.

Structural studies
As of late 2007, 10 structures have been solved for this class of enzymes, with PDB accession codes, , , , , , , , , and.