2I5D: Crystal Structure Of Human Inosine Triphosphate Pyrophosphatase

The structure of human inosine triphosphate pyrophosphohydrolase (ITPA) has been determined using diffraction data to 1.6 A resolution. ITPA contributes to the accurate replication of DNA by cleansing cellular dNTP pools of mutagenic nucleotide purine analogs such as dITP or dXTP. A similar high-resolution unpublished structure has been deposited in the Protein Data Bank from a monoclinic and pseudo-merohedrally twinned crystal. Here, cocrystallization of ITPA with a molar ratio of XTP appears to have improved the crystals by eliminating twinning and resulted in an orthorhombic space group. However, there was no evidence for bound XTP in the structure. Comparison with substrate-bound NTPase from a thermophilic organism predicts the movement of residues within helix alpha1, the loop before alpha6 and helix alpha7 to cap off the active site when substrate is bound.
PDB ID: 2I5DDownload
MMDB ID: 41216
PDB Deposition Date: 2006/8/24
Updated in MMDB: 2006/12
Experimental Method:
x-ray diffraction
Resolution: 1.63  Å
Source Organism:
Similar Structures:
Biological Unit for 2I5D: dimeric; determined by author
Molecular Components in 2I5D
Label Count Molecule
Proteins (2 molecules)
Inosine Triphosphate Pyrophosphohydrolase(Gene symbol: ITPA)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB