5AGP

Structure of rat neuronal nitric oxide synthase heme domain in complex with (S)-2-Amino-5-(2-mercaptoacetimidamido)pentanoic acid


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Mechanism of Inactivation of Neuronal Nitric Oxide Synthase by (S)-2-Amino-5-(2-(Methylthio)Acetimidamido)Pentanoic Acid.

Tang, W.Li, H.Doud, E.H.Chen, Y.Choing, S.Plaza, C.Kelleher, N.L.Poulos, T.L.Silverman, R.B.

(2015) J.Am.Chem.Soc. 137: 5980

  • DOI: 10.1021/jacs.5b01202
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Nitric oxide synthase (NOS) catalyzes the conversion of l-arginine to l-citrulline and the second messenger nitric oxide. Three mechanistic pathways are proposed for the inactivation of neuronal NOS (nNOS) by (S)-2-amino-5-(2-(methylthio)acetimidamid ...

    Nitric oxide synthase (NOS) catalyzes the conversion of l-arginine to l-citrulline and the second messenger nitric oxide. Three mechanistic pathways are proposed for the inactivation of neuronal NOS (nNOS) by (S)-2-amino-5-(2-(methylthio)acetimidamido)pentanoic acid (1): sulfide oxidation, oxidative dethiolation, and oxidative demethylation. Four possible intermediates were synthesized. All compounds were assayed with nNOS, their IC50, KI, and kinact values were obtained, and their crystal structures were determined. The identification and characterization of the products formed during inactivation provide evidence for the details of the inactivation mechanism. On the basis of these studies, the most probable mechanism for the inactivation of nNOS involves oxidative demethylation with the resulting thiol coordinating to the cofactor heme iron. Although nNOS is a heme-containing enzyme, this is the first example of a NOS that catalyzes an S-demethylation reaction; the novel mechanism of inactivation described here could be applied to the design of inactivators of other heme-dependent enzymes.


    Organizational Affiliation

    †Department of Chemistry, Department of Molecular Biosciences, Chemistry of Life Processes Institute, and Center for Molecular Innovation and Drug Discovery, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
NITRIC OXIDE SYNTHASE, BRAIN
A, B
422Rattus norvegicusMutation(s): 0 
Gene Names: Nos1 (Bnos)
EC: 1.14.13.39
Find proteins for P29476 (Rattus norvegicus)
Go to UniProtKB:  P29476
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

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Download CCD File 
B
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

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Download CCD File 
A, B
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
HEM
Query on HEM

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Download CCD File 
A, B
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
VUR
Query on VUR

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Download CCD File 
A, B
(S)-2-AMINO-5-(2-MERCAPTOACETIMIDAMIDO)PENTANOIC ACID
C7 H15 N3 O2 S
ROQCTZSRBCTHGN-YFKPBYRVSA-N
 Ligand Interaction
H4B
Query on H4B

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Download CCD File 
A, B
5,6,7,8-TETRAHYDROBIOPTERIN
C9 H15 N5 O3
FNKQXYHWGSIFBK-RPDRRWSUSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.251 
  • R-Value Work: 0.196 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 51.867α = 90.00
b = 110.622β = 90.00
c = 164.205γ = 90.00
Software Package:
Software NamePurpose
REFMACphasing
XDSdata reduction
REFMACrefinement
Aimlessdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2015-02-02 
  • Released Date: 2015-04-29 
  • Deposition Author(s): Li, H., Poulos, T.L.

Revision History 

  • Version 1.0: 2015-04-29
    Type: Initial release
  • Version 1.1: 2015-05-27
    Type: Database references