| Inositol polyphosphate kinase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 Structure of the Inositol 1,4,5-trisphosphate 3-kinase A protein. | |||||||||
| Identifiers | |||||||||
| Symbol | IPK | ||||||||
| Pfam | PF03770 | ||||||||
| InterPro | IPR005522 | ||||||||
| SCOP2 | 1tzd / SCOPe / SUPFAM | ||||||||
| |||||||||
Inositol polyphosphate kinase (IPK) is a family of enzymes [1] that have a similar 3-dimensional structure. All members of the family catalyze the transfer of phosphate groups from ATP to various inositol phosphates. Members of the family include inositol-polyphosphate multikinases, inositol-hexakisphosphate kinases, inositol-trisphosphate 3-kinases, and inositol-pentakisphosphate 2-kinase, which is more distantly related to the others [2] [3]
The discovery of the IPK family occurred in 1999, when a combination of biochemistry, sequence analysis, and genetics led to the classification of a family of inositol polyphosphate kinases. [4] [5] In 2005, the first crystal structures of an IPK family protein were published for ITPKA. [6] [7]
Subsequently, structures of the inositol polyphosphate multikinase and various IP6 kinases have expanded our structural understanding for how each enzyme catalyzes its specific reaction(s).