3OZU

The Crystal Structure of flavohemoglobin from R. eutrophus in complex with miconazole


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of Ralstonia eutropha Flavohemoglobin in Complex with Three Antibiotic Azole Compounds.

El Hammi, E.Warkentin, E.Demmer, U.Limam, F.Marzouki, N.M.Ermler, U.Baciou, L.

(2011) Biochemistry 50: 1255-1264

  • DOI: 10.1021/bi101650q
  • Primary Citation of Related Structures:  3OZV, 3OZW

  • PubMed Abstract: 
  • Flavohemoglobins (flavoHbs) are enzymes that operate primarily as nitric oxide dioxygenases and shuttle thereby electrons among NAD(P)H, FAD, heme, and a ligated redox-active substrate such as O(2). They function in the bacterial defense against nitr ...

    Flavohemoglobins (flavoHbs) are enzymes that operate primarily as nitric oxide dioxygenases and shuttle thereby electrons among NAD(P)H, FAD, heme, and a ligated redox-active substrate such as O(2). They function in the bacterial defense against nitrosative stress and are therefore considered as targets for new antibiotic drugs. Recently, azole derivatives were proven to be attractive nitric oxide dioxygenase inhibitors, and to explore their binding characteristics, we determined the X-ray structure of the flavoHb from Ralstonia eutropha in a complex with miconazole (FHP(M)), econazole (FHP(E)), and ketoconazole (FHP(K)). In agreement with UV-vis spectroscopic data, one azole compound binds inside the distal heme pocket and ligates to the heme iron by its imidazole substituent. The two additional substituents, mostly chlorinated phenyl groups, form a series of van der Waals contacts with the protein matrix. Both interactions explain their high affinity for flavoHbs, the binding constants being 2.6, 1.2, and 11.6 μM for miconazole, econazole, and ketoconazole, respectively. The FHP(M) and FHP(Lip) (flavoHbs originally loaded with a phospholipid) structures share an "open" state and the FHP(E) and FHP(K) structures a "closed" state. Although the azole compounds were able to push the lipid out of its binding site, a fatty acid fragment is still bound inside the heme pocket of FHP(E) and FHP(K) and dictates the state of the protein. The ligand-induced open-to-closed transition involves a reorientation of the NADH domain accompanied by conformational changes in the C-terminal arm, helix E, and the CE loop resulting in an encapsulation of the heme-binding pocket. Implications of the observed open-to-closed process on the catalytic cycle are discussed.


    Organizational Affiliation

    Laboratoire de Chimie Physique, CNRS-Université Paris-Sud 11, UMR8000, F-91405 Orsay, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Flavohemoprotein
A
403Cupriavidus necator (strain ATCC 17699 / H16 / DSM 428 / Stanier 337)Gene Names: hmp (fhp)
EC: 1.14.12.17
Find proteins for P39662 (Cupriavidus necator (strain ATCC 17699 / H16 / DSM 428 / Stanier 337))
Go to UniProtKB:  P39662
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
X89
Query on X89

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Download CCD File 
A
1-[(2R)-2-[(2,4-dichlorobenzyl)oxy]-2-(2,4-dichlorophenyl)ethyl]-1H-imidazole
C18 H14 Cl4 N2 O
BYBLEWFAAKGYCD-SFHVURJKSA-N
 Ligand Interaction
FAD
Query on FAD

Download SDF File 
Download CCD File 
A
FLAVIN-ADENINE DINUCLEOTIDE
C27 H33 N9 O15 P2
VWWQXMAJTJZDQX-UYBVJOGSSA-N
 Ligand Interaction
HEM
Query on HEM

Download SDF File 
Download CCD File 
A
PROTOPORPHYRIN IX CONTAINING FE
HEME
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
X89Kd: 2600 nM BINDINGMOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.185 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 121.339α = 90.00
b = 105.278β = 101.90
c = 46.445γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
EPMRphasing
XDSdata scaling
MAR345dtbdata collection
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-03-16
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance