Inositol-polyphosphate Multikinase

Inositol-polyphosphate multikinase (, ''IpK2'', ''IP3/IP4 6-/3-kinase'', ''IP3/IP4 dual-specificity 6-/3-kinase'', ''IpmK'', ''ArgRIII'', ''AtIpk2alpha'', ''AtIpk2beta'', ''inositol polyphosphate 6-/3-/5-kinase'') is an enzyme with systematic name ''ATP:1D-myo-inositol-1,4,5-trisphosphate 6-phosphotransferase''. This enzyme catalyses the following chemical reaction

: 2 ATP + 1D-myo-inositol 1,4,5-trisphosphate $\rightleftharpoons$ 2 ADP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate (overall reaction)
:(1a) ATP + 1D-myo-inositol 1,4,5-trisphosphate $\rightleftharpoons$ ADP + 1D-myo-inositol 1,4,5,6-tetrakisphosphate
:(1b) ATP + 1D-myo-inositol 1,4,5,6-tetrakisphosphate $\rightleftharpoons$ ADP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate

This enzyme also phosphorylates Ins(1,4,5)P3 to Ins(1,3,4,5)P4, Ins(1,3,4,5)P4 to Ins(1,3,4,5,6)P5, and Ins(1,3,4,5,6)P4 to Ins(PP)P4, isomer unknown.

References

{{Portal bar, Biology, border=no

EC 2.7.1