Tags: Enzyme.
In enzymology a [RNA-polymerase]-subunit kinase (EC 2.7.11.23) is an enzyme that catalyzes the chemical reactionATP + [DNA-directed RNA polymerase] ADP + phospho-[DNA-directed RNA polymerase]Thus the two substrates of this enzyme are ATP and DNA-directed RNA polymerase whereas its two products are ADP and [[phospho-[DNA-directed RNA polymerase]]].This enzyme belongs to the family of transferases specifically those transferring a phosphate group to the sidechain oxygen atom of serine or threonine residues in proteins (protein-serine/threonine kinases).