1K2U

Structure of rat brain nNOS heme domain complexed with S-ethyl-N-[4-(trifluoromethyl)phenyl] isothiourea

• PDB DOI: https://doi.org/10.2210/pdb1K2U/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Rattus norvegicus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-09-28 Released: 2003-03-04 
• Deposition Author(s): Li, H., Martasek, P., Masters, B.S.S., Poulos, T.L., Raman, C.S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.261 
• R-Value Work: 0.227 
• R-Value Observed: 0.227 

Literature

Structure of rat brain nNOS heme domain

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

To be published.

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: 99.51 kDa 
• Atom Count: 7,169 
• Modelled Residue Count: 817 
• Deposited Residue Count: 838 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
nitric-oxide synthase	A, B	419	Rattus norvegicus	Mutation(s): 0  Gene Names: brain EC: 1.14.13.39
UniProt
Find proteins for P29476 (Rattus norvegicus) Explore P29476  Go to UniProtKB:  P29476

Small Molecules

Ligands 5 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEM	E [auth A], I [auth B]	PROTOPORPHYRIN IX CONTAINING FE C34 H32 Fe N4 O4 KABFMIBPWCXCRK-RGGAHWMASA-L
TFM	G [auth A], K [auth B]	S-ETHYL-N-[4-(TRIFLUOROMETHYL)PHENYL]ISOTHIOUREA C10 H11 F3 N2 S LCMOXIFARISMOH-UHFFFAOYSA-N
H4B	F [auth A], J [auth B]	5,6,7,8-TETRAHYDROBIOPTERIN C9 H15 N5 O3 FNKQXYHWGSIFBK-RPDRRWSUSA-N
ZN	D [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
ACT	C [auth A], H [auth B]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M

Binding Affinity Annotations
ID	Source	Binding Affinity
TFM	BindingDB:  1K2U	Ki: 320 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.261 
• R-Value Work: 0.227 
• R-Value Observed: 0.227 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 51.72	α = 90
b = 110.66	β = 90
c = 164.91	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
CNS	refinement
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2003-03-04 
Deposition Author(s): Li, H., Martasek, P., Masters, B.S.S., Poulos, T.L., Raman, C.S.

Revision History  

• Version 1.0: 2003-03-04
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references, Derived calculations