1Z2N

Inositol 1,3,4-trisphosphate 5/6-kinase complexed Mg2+/ADP

Summary for 1Z2N

• Entry DOI: 10.2210/pdb1z2n/pdb
• Related: 1Z2O 1Z2P
• Descriptor: inositol 1,3,4-trisphosphate 5/6-kinase, MAGNESIUM ION, ADENOSINE-5'-DIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: inositol phosphate kinase, atp-grasp, transferase
• Biological source: Entamoeba histolytica
• Total number of polymer chains: 1
• Total formula weight: 37387.95

Authors

Miller, G.J.,Wilson, M.P.,Majerus, P.W.,Hurley, J.H. (deposition date: 2005-03-08, release date: 2005-04-19, Last modification date: 2024-02-14)

Primary citation

Miller, G.J.,Wilson, M.P.,Majerus, P.W.,Hurley, J.H.
Specificity determinants in inositol polyphosphate synthesis: crystal structure of inositol 1,3,4-trisphosphate 5/6-kinase.
Mol.Cell, 18:201-212, 2005

PubMed Abstract: Inositol hexakisphosphate and other inositol high polyphosphates have diverse and critical roles in eukaryotic regulatory pathways. Inositol 1,3,4-trisphosphate 5/6-kinase catalyzes the rate-limiting step in inositol high polyphosphate synthesis in animals. This multifunctional enzyme also has inositol 3,4,5,6-tetrakisphosphate 1-kinase and other activities. The structure of an archetypal family member, from Entamoeba histolytica, has been determined to 1.2 A resolution in binary and ternary complexes with nucleotide, substrate, and product. The structure reveals an ATP-grasp fold. The inositol ring faces ATP edge-on such that the 5- and 6-hydroxyl groups are nearly equidistant from the ATP gamma-phosphate in catalytically productive phosphoacceptor positions and explains the unusual dual site specificity of this kinase. Inositol tris- and tetrakisphosphates interact via three phosphate binding subsites and one solvent-exposed site that could in principle be occupied by 18 different substrates, explaining the mechanisms for the multiple specificities and catalytic activities of this enzyme.

PubMed: 15837423
DOI: 10.1016/j.molcel.2005.03.016

Experimental method

X-RAY DIFFRACTION (1.2 Å)