4AS4

Structure of human inositol monophosphatase 1

• PDB DOI: https://doi.org/10.2210/pdb4AS4/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2012-04-27 Released: 2012-10-10 
• Deposition Author(s): Singh, N., Knight, M., Halliday, A.C., Lack, N.A., Lowe, E.D., Churchill, G.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free: 0.186 
• R-Value Work: 0.152 
• R-Value Observed: 0.154 

Starting Model: experimental

Literature

Cloning, Expression, Purification, Crystallization and X-Ray Analysis of Inositol Monophosphatase from Mus Musculus and Homo Sapiens.

Singh, N., Halliday, A.C., Knight, M., Lack, N.A., Lowe, E.D., Churchill, G.C.

(2012) Acta Crystallogr Sect F Struct Biol Cryst Commun 68: 1149

• PubMed: 23027737 
• DOI: https://doi.org/10.1107/S1744309112035191
• Primary Citation of Related Structures:  
  4AS4, 4AS5


• PubMed Abstract: 
  

  Inositol monophosphatase (IMPase) catalyses the hydrolysis of inositol monophosphate to inositol and is crucial in the phosphatidylinositol (PI) signalling pathway. Lithium, which is the drug of choice for bipolar disorder, inhibits IMPase at therapeutically relevant plasma concentrations. Both mouse IMPase 1 (MmIMPase 1) and human IMPase 1 (HsIMPase 1) were cloned into pRSET5a, expressed in Escherichia coli, purified and crystallized using the sitting-drop method. The structures were solved at resolutions of 2.4 and 1.7 Å, respectively. Comparison of MmIMPase 1 and HsIMPase 1 revealed a core r.m.s. deviation of 0.516 Å.

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Organizational Affiliation: 

Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 61.42 kDa 
• Atom Count: 4,963 
• Modelled Residue Count: 548 
• Deposited Residue Count: 554 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INOSITOL MONOPHOSPHATASE 1	A, B	277	Homo sapiens	Mutation(s): 0  EC: 3.1.3.25 (PDB Primary Data), 3.1.3.94 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P29218 (Homo sapiens) Explore P29218  Go to UniProtKB:  P29218
PHAROS:  P29218 GTEx:  ENSG00000133731

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PO4	C [auth A], K [auth B]	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K
GOL	G [auth A], H [auth A], I [auth A], J [auth A], O [auth B], P [auth B], Q [auth B]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
MG	D [auth A], E [auth A], F [auth A], L [auth B], M [auth B], N [auth B]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.70 Å
• R-Value Free: 0.186 
• R-Value Work: 0.152 
• R-Value Observed: 0.154 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 60.613	α = 90
b = 76.199	β = 90
c = 117.648	γ = 90

Software Package:

Software Name	Purpose
BUSTER	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-10-10 
Deposition Author(s): Singh, N., Knight, M., Halliday, A.C., Lack, N.A., Lowe, E.D., Churchill, G.C.

Revision History  

• Version 1.0: 2012-10-10
  Type: Initial release
  
• Version 1.1: 2012-10-17
  Changes: Database references
• Version 1.2: 2023-12-20
  Changes: Data collection, Database references, Derived calculations, Other, Refinement description
• Version 1.3: 2024-11-13
  Changes: Structure summary