3NOS | pdb_00003nos

HUMAN ENDOTHELIAL NITRIC OXIDE SYNTHASE WITH ARGININE SUBSTRATE

• PDB DOI: https://doi.org/10.2210/pdb3NOS/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1999-02-03 Released: 2000-02-04 
• Deposition Author(s): Fischmann, T.O., Weber, P.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free: 
  0.308 (Depositor) 
• R-Value Work: 
  0.193 (Depositor) 

Literature

Structural characterization of nitric oxide synthase isoforms reveals striking active-site conservation.

Fischmann, T.O., Hruza, A., Niu, X.D., Fossetta, J.D., Lunn, C.A., Dolphin, E., Prongay, A.J., Reichert, P., Lundell, D.J., Narula, S.K., Weber, P.C.

(1999) Nat Struct Biol 6: 233-242

• PubMed: 10074942 
• DOI: https://doi.org/10.1038/6675
• Primary Citation Related Structures: 
  3NOS, 4NOS


• PubMed Abstract: 
  

  Crystal structures of human endothelial nitric oxide synthase (eNOS) and human inducible NOS (iNOS) catalytic domains were solved in complex with the arginine substrate and an inhibitor S-ethylisothiourea (SEITU), respectively. The small molecules bind in a narrow cleft within the larger active-site cavity containing heme and tetrahydrobiopterin. Both are hydrogen-bonded to a conserved glutamate (eNOS E361, iNOS E377). The active-site residues of iNOS and eNOS are nearly identical. Nevertheless, structural comparisons provide a basis for design of isozyme-selective inhibitors. The high-resolution, refined structures of eNOS (2.4 A resolution) and iNOS (2.25 A resolution) reveal an unexpected structural zinc situated at the intermolecular interface and coordinated by four cysteines, two from each monomer.

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Organizational Affiliation: 
• Structural Chemistry Department, Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA. [e-mail]

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,PQS (software)

Macromolecule Content 

• Total Structure Weight: 98.2 kDa 
• Atom Count: 7,042 
• Modeled Residue Count: 800 
• Deposited Residue Count: 854 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ENDOTHELIAL NITRIC-OXIDE SYNTHASE	A, B	427	Homo sapiens	Mutation(s): 0  EC: 1.14.13.39
UniProt & NIH Common Fund Data Resources
Find proteins for P29474 (Homo sapiens) Explore P29474  Go to UniProtKB:  P29474
PHAROS:  P29474 GTEx:  ENSG00000164867

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEM	E [auth A], H [auth B]	PROTOPORPHYRIN IX CONTAINING FE C34 H32 Fe N4 O4 KABFMIBPWCXCRK-RGGAHWMASA-L
H4B	F [auth A], I [auth B]	5,6,7,8-TETRAHYDROBIOPTERIN C9 H15 N5 O3 FNKQXYHWGSIFBK-RPDRRWSUSA-N
HAR	D [auth A], G [auth B]	N-OMEGA-HYDROXY-L-ARGININE C6 H14 N4 O3 FQWRAVYMZULPNK-BYPYZUCNSA-N
ZN	C [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.40 Å
• R-Value Free:  0.308 (Depositor) 
• R-Value Work:  0.193 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 68.859	α = 90
b = 93.264	β = 90
c = 156.117	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
SHARP	phasing
SOLOMON	phasing
DM	model building
X-PLOR	refinement
DENZO	data reduction
CCP4	data scaling
DM	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-02-04 
Deposition Author(s): Fischmann, T.O., Weber, P.C.

Revision History  

• Version 1.0: 2000-02-04
  Type: Initial release
  
• Version 1.1: 2007-10-16
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2023-12-27
  Changes: Data collection, Database references, Derived calculations