Adenylate kinases in man: evidence for a third locus

Abstract
The tissue distribution of the adenylate kinase isozymes in man has been examined using various substrates. The isozymes attributable to the AK1 and AK2 loci were identified, and an additional set of isozymes probably attributable to a third locus was also found. This locus has been provisionally designated AK3. The AK3 isozymes show activity with either GTP + AMP or ITP + AMP but do not show activity with ATP + AMP. They also differ from the AK1 end AK2 isozymes in electrophoretic mobility and from the AK1 isozymes in being resistant to silver inhibition. They are similar in molecular size to the AK1 isozymes whereas the AK2 isozymes are apparently larger. The AK3 isozymes evidently correspond to the enzyme nucleosidetriphosphate-adenylate kinase (2.7.4.10).