2NOS

MURINE INDUCIBLE NITRIC OXIDE SYNTHASE OXYGENASE DOMAIN (DELTA 114), AMINOGUANIDINE COMPLEX

• PDB DOI: https://doi.org/10.2210/pdb2NOS/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Mus musculus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1997-09-28 Released: 1998-10-14 
• Deposition Author(s): Crane, B.R., Arvai, A.S., Getzoff, E.D., Stuehr, D.J., Tainer, J.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.267 
• R-Value Work: 0.204 
• R-Value Observed: 0.204 

Literature

The structure of nitric oxide synthase oxygenase domain and inhibitor complexes.

Crane, B.R., Arvai, A.S., Gachhui, R., Wu, C., Ghosh, D.K., Getzoff, E.D., Stuehr, D.J., Tainer, J.A.

(1997) Science 278: 425-431

• PubMed: 9334294 
• DOI: https://doi.org/10.1126/science.278.5337.425
• Primary Citation of Related Structures:  
  1NOC, 1NOS, 2NOS


• PubMed Abstract: 
  

  The nitric oxide synthase oxygenase domain (NOSox) oxidizes arginine to synthesize the cellular signal and defensive cytotoxin nitric oxide (NO). Crystal structures determined for cytokine-inducible NOSox reveal an unusual fold and heme environment for stabilization of activated oxygen intermediates key for catalysis. A winged beta sheet engenders a curved alpha-beta domain resembling a baseball catcher's mitt with heme clasped in the palm. The location of exposed hydrophobic residues and the results of mutational analysis place the dimer interface adjacent to the heme-binding pocket. Juxtaposed hydrophobic O2- and polar L-arginine-binding sites occupied by imidazole and aminoguanidine, respectively, provide a template for designing dual-function inhibitors and imply substrate-assisted catalysis.

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Organizational Affiliation: 

Department of Molecular Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 45.9 kDa 
• Atom Count: 2,873 
• Modelled Residue Count: 322 
• Deposited Residue Count: 388 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
INDUCIBLE NITRIC OXIDE SYNTHASE	A	388	Mus musculus	Mutation(s): 0  EC: 1.14.13.39
UniProt & NIH Common Fund Data Resources
Find proteins for P29477 (Mus musculus) Explore P29477  Go to UniProtKB:  P29477
IMPC:  MGI:97361

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEM	B [auth A]	PROTOPORPHYRIN IX CONTAINING FE C34 H32 Fe N4 O4 KABFMIBPWCXCRK-RGGAHWMASA-L
AGU	D [auth A]	AMINOGUANIDINE C H6 N4 HAMNKKUPIHEESI-UHFFFAOYSA-N
IMD	C [auth A]	IMIDAZOLE C3 H5 N2 RAXXELZNTBOGNW-UHFFFAOYSA-O

Binding Affinity Annotations
ID	Source	Binding Affinity
AGU	BindingDB:  2NOS	IC50: min: 3900, max: 1.32e+5 (nM) from 8 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.267 
• R-Value Work: 0.204 
• R-Value Observed: 0.204 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 63	α = 90
b = 73.8	β = 90
c = 92.8	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1998-10-14 
Deposition Author(s): Crane, B.R., Arvai, A.S., Getzoff, E.D., Stuehr, D.J., Tainer, J.A.

Revision History  

• Version 1.0: 1998-10-14
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-21
  Changes: Data collection, Database references, Derived calculations, Other