Reaction: (1) ATP + 1D-myo-inositol hexakisphosphate = ADP + 1D-myo-inositol 5-diphosphate 1,2,3,4,6-pentakisphosphate
(2) ATP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate = ADP + 1D-myo-inositol diphosphate tetrakisphosphate (isomeric configuration unknown)
Other name(s): ATP:1D-myo-inositol-hexakisphosphate phosphotransferase
Systematic name: ATP:1D-myo-inositol-hexakisphosphate 5-phosphotransferase
Comments: Three mammalian isoforms are known to exist.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 176898-37-6
References:
1. Saiardi, A., Erdjument-Bromage, H., Snowman, A.M., Tempst, P. and Snyder, S.H. Synthesis of diphosphoinositol pentakisphosphate by a newly identified family of higher inositol polyphosphate kinases. Curr. Biol. 9 (1999) 1323-1326. [PMID: 10574768]
2. Schell, M.J., Letcher, A.J., Brearley, C.A., Biber, J., Murer, H. and Irvine, R.F. PiUS (Pi uptake stimulator) is an inositol hexakisphosphate kinase. FEBS Lett. 461 (1999) 169-172. [PMID: 10567691]
3. Albert, C., Safrany, S.T., Bembenek, M.E., Reddy, K.M., Reddy, K.K., Falck, J.-R., Bröcker, M., Shears, S.B. and Mayr, G.W. Biological variability in the structures of diphosphoinositol polyphosphates in Dictyostelium discoideum and mammalian cells. Biochem. J. 327 (1997) 553-560. [PMID: 9359429]