Choline kinase

choline kinase is an enzyme that catalyzes the chemical reaction between ATP and choline to make a phosphocholine.


 * ATP + choline $$\rightleftharpoons$$ ADP + O-phosphocholine

Thus, the two substrates of this enzyme are ATP and choline, whereas its two products are ADP and O-phosphocholine.

This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with an alcohol group as acceptor. The first detailed investigation of the enzyme was conducted by McCamen in 1962, where it was shown that the brain is the richest source of the enzyme in mammalian tissue. A related enzyme, ethanolamine kinase tends to co-purify with choline kinase leading to a suggestion that the two activities are mediated by two distinct active sites on a single protein. The systematic name of this enzyme class is ATP:choline phosphotransferase. These enzymes participate in glycine, serine and threonine metabolism and glycerophospholipid metabolism.

Structural studies
As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes, , , , , and.