Adenylate kinases (ADK) are phosphotransferases that catalyse the reversible reaction
AMP + MgATP = ADP + MgADP
an essential reaction for many processes in living cells. Two ADK isozymes
have been identified in mammalian cells. These specifically bind AMP and favour binding to ATP over
other nucleotide triphosphates (AK1 is cytosolic and AK2 is located in the mitochondria). A third ADK
has been identified in bovine heart and human cells [PMID: 6088234], this is a mitochondrial GTP:AMP
phosphotransferase, also specific for the phosphorylation of AMP, but can only use GTP or ITP as a
substrate [PMID: 218813]. ADK has also been identified in different bacterial species and in yeast
[PMID: 1587477]. Two further enzymes are known to be related to the ADK family, i.e. yeast uridine
monophosphokinase and slime mold UMP-CMP kinase. Within the ADK family there are several conserved
regions, including the ATP-binding domains. One of the most conserved areas includes an Arg residue,
whose modification inactivates the enzyme, together with an Asp that resides in the catalytic cleft
of the enzyme and participates in a salt bridge.
In humans, nine different AK isoenzymes have been identified (AK1-9) [PMID: 23416111].
GO:0006139 nucleobase-containing compound metabolic process
GO:0005524 ATP binding
GO:0019205 nucleobase-containing compound kinase activity
No terms assigned in this category.