Adenylate kinase

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Adenylate kinase 1
Identifiers
Symbol	AK1
Entrez	203
HUGO	361
OMIM	103000
RefSeq	NM_000476
UniProt	P00568
Other data
EC number	2.7.4.3
Locus	Chr. 9 q34.1

Adenylate kinase (also known as ADK or myokinase) is a phosphotransferase enzyme that catalyzes the interconversion of adenine nucleotides, and plays an important role in cellular energy homeostasis (see the "Biological homeostasis" section of "Homeostasis"). The reaction catalyzed is:

2 ADP ⇔ ATP + AMP

The equilibrium constant in the direction written is 0.44. Thus, the ΔG^o for this reaction is close to zero. In muscle of a variety of species of vertebrates and invertebrates, the concentration of ATP is typically 7-10 times that of ADP, and usually greater than 100 times that of AMP ^[1]. The rate of oxidative phosphorylation is controlled by the availability of ADP. Thus, the mitochondrion attempts to keep ATP levels high due to the combined action of adenylate kinase and the controls on oxidative phosphorylation.

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• MeSH Adenylate+kinase

v • d • e Transferases: Phosphotransferases/kinases (EC 2.7) 2.7.1 - OH acceptor Hexo- - Gluco- - Fructo- (Hepatic fructo-) - Galacto- - Phosphofructo- (1, 2) - Riboflavin - Shikimate - Thymidine - NAD+ - Glycerol - Pantothenate - Mevalonate - Pyruvate - Deoxycytidine - PFP - Diacylglycerol - Bruton's tyrosine - Phosphoinositide 3 (Class I PI 3, Class II PI 3) - Sphingosine 2.7.2 - COOH acceptor Phosphoglycerate - Aspartate 2.7.3 - N acceptor Creatine 2.7.4 - PO4 acceptor Phosphomevalonate - Adenylate - Nucleoside-diphosphate 2.7.6 - P2O7 Ribose-phosphate diphosphokinase - Thiamine pyrophosphokinase 2.7.7 - nucleotidyl- Integrase - PNPase - Polymerase - RNase PH - UDP-glucose pyrophosphorylase - Galactose-1-phosphate uridylyltransferase -Terminal deoxynucleotidyl transferase - RNA replicase - Reverse transcriptase (Telomerase) - Transposase 2.7.8 - other phos. N-acetylglucosamine-1-phosphate transferase 2.7.10-11 - protein Tyrosine - Serine/threonine-specific

v • d • e Mitochondrial enzymes and transporters Outer membrane fatty acid degradation (Carnitine palmitoyltransferase I, Long fatty acyl CoA synthetase) tryptophan metabolism (Kynureninase) monoamine neurotransmitter metabolism (Monoamine oxidase) Intermembrane space Adenylate kinase - Creatine kinase Inner membrane oxidative phosphorylation (Coenzyme Q - cytochrome c reductase, Cytochrome c, NADH dehydrogenase, Succinate dehydrogenase) pyrimidine metabolism (Dihydroorotate dehydrogenase) mitochondrial shuttle (Malate-aspartate shuttle, Glycerol phosphate shuttle) other (Glutamate aspartate transporter, Glycerol-3-phosphate dehydrogenase, ATP synthase, Carnitine palmitoyltransferase II) Matrix citric acid cycle (Citrate synthase, Aconitase, Isocitrate dehydrogenase, Oxoglutarate dehydrogenase, Succinyl coenzyme A synthetase, Fumarase, Malate dehydrogenase) anaplerotic reactions (Aspartate transaminase, Glutamate dehydrogenase, Pyruvate dehydrogenase complex) urea cycle (Carbamoyl phosphate synthetase I, Ornithine transcarbamylase, N-Acetylglutamate synthase) alcohol metabolism (ALDH2) Other/to be sorted Cholesterol side-chain cleavage enzyme Mitochondrial DNA Complex I (7 units) - Complex III (1 unit) - Complex IV (3 units) - ATP synthase (2 units)