Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 102.38 kDa 
• Atom Count: 7192 
• Modelled Residue Count: 830 
• Deposited Residue Count: 888 
• Unique protein chains: 1

1D0O

BOVINE ENDOTHELIAL NITRIC OXIDE SYNTHASE HEME DOMAIN COMPLEXED WITH 3-BROMO-7-NITROINDAZOLE (H4B PRESENT)

• DOI: 10.2210/pdb1D0O/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Bos taurus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-09-13 Released: 2001-11-21 
• Deposition Author(s): Raman, C.S., Li, H., Martasek, P., Southan, G.J., Masters, B.S.S., Poulos, T.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.95 Å
• R-Value Free: 0.247 
• R-Value Work: 0.200 

Literature

Crystal structure of nitric oxide synthase bound to nitro indazole reveals a novel inactivation mechanism.

Raman, C.S., Li, H., Martasek, P., Southan, G., Masters, B.S., Poulos, T.L.

(2001) Biochemistry 40: 13448-13455

• PubMed: 11695891 
• DOI: 10.1021/bi010957u
• Primary Citation of Related Structures:  
  1ED5, 1DM6, 1D0O, 1D0C, 8NSE, 1FOJ


• PubMed Abstract: 
  

Nitric oxide is generated under normal and pathophysiological conditions by three distinct isoforms of nitric oxide synthase (NOS). A small-molecule inhibitor of NOS (3-Br-7-nitroindazole, 7-NIBr) is profoundly neuroprotective in mouse models of stroke and Parkinson's disease. We report the crystal structure of the catalytic heme domain of endothelial NOS complexed with 7-NIBr at 1.65 A resolution. Critical to the binding of 7-NIBr at the substrate site is the adoption by eNOS of an altered conformation, in which a key glutamate residue swings out toward one of the heme propionate groups. Perturbation of the heme propionate ensues and eliminates the cofactor tetrahydrobiopterin-heme interaction. We also present three crystal structures that reveal how alterations at the substrate site facilitate 7-NIBr and structurally dissimilar ligands to occupy the cofactor site.

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Related Citations: 

• Crystal Structure of Constitutive Endothelial Nitric Oxide Synthase: a Paradigm for Pterin Function Involving a Novel Metal Center
  Raman, C.S., Li, H., Martasek, P., Kral, V., Masters, B.S., Poulos, T.L.
  (1998) Cell 95: 939

• Structure of Nitric Oxide Synthase Oxygenase Dimer with Pterin and Substrate
  Crane, B.R., Arvai, A.S., Ghosh, D.K., Wu, C., Getzoff, E.D., Stuehr, D.J., Tainer, J.A.
  (1998) Science 279: 2121

• 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

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Organizational Affiliation: 

Department of Molecular Biology & Biochemistry, University of California, Irvine, California 92697, USA. [e-mail]

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
BOVINE ENDOTHELIAL NITRIC OXIDE SYNTHASE HEME	A, B	444	Bos taurus	Mutation(s): 0  Gene Names: NOS3 EC: 1.14.13.39
UniProt
Find proteins for P29473 (Bos taurus) Explore P29473  Go to UniProtKB:  P29473

Small Molecules

Ligands 6 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEM	F [auth A], N [auth B]	PROTOPORPHYRIN IX CONTAINING FE C34 H32 Fe N4 O4 KABFMIBPWCXCRK-RGGAHWMASA-L
INE	G [auth A], I [auth A], M [auth B], O [auth B]	3-BROMO-7-NITROINDAZOLE C7 H4 Br N3 O2 NFSTZPMYAZRZPC-UHFFFAOYSA-N
CAD	H [auth A], P [auth B]	CACODYLIC ACID C2 H7 As O2 OGGXGZAMXPVRFZ-UHFFFAOYSA-N
GOL	J [auth A], Q [auth B]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
ZN	E [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
ACT	C [auth A], D [auth A], K [auth B], L [auth B]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
INE	IC50:  2000   nM  BindingDB

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.95 Å
• R-Value Free: 0.247 
• R-Value Work: 0.200 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 57.59	α = 90
b = 106.06	β = 90
c = 155.78	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

• Deposited Date: 1999-09-13 
• Released Date: 2001-11-21 
Deposition Author(s): Raman, C.S., Li, H., Martasek, P., Southan, G.J., Masters, B.S.S., Poulos, T.L.

Revision History  

• Version 1.0: 2001-11-21
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Non-polymer description, Version format compliance