1BKJ

NADPH:FMN OXIDOREDUCTASE FROM VIBRIO HARVEYI


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.175 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Flavin reductase P: structure of a dimeric enzyme that reduces flavin.

Tanner, J.J.Lei, B.Tu, S.C.Krause, K.L.

(1996) Biochemistry 35: 13531-13539

  • DOI: 10.1021/bi961400v

  • PubMed Abstract: 
  • We report the structure of an NADPH:FMN oxidoreductase (flavin reductase P) that is involved in bioluminescence by providing reduced FMN to luciferase. The 1.8 A crystal structure of flavin reductase P from Vibrio harveyi was solved by multiple isomo ...

    We report the structure of an NADPH:FMN oxidoreductase (flavin reductase P) that is involved in bioluminescence by providing reduced FMN to luciferase. The 1.8 A crystal structure of flavin reductase P from Vibrio harveyi was solved by multiple isomorphous replacement and reveals that the enzyme is a unique dimer of interlocking subunits, with 9352 A2 of surface area buried in the dimer interface. Each subunit comprises two domains. The first domain consists of a four-stranded antiparallel beta-sheet flanked by helices on either side. The second domain reaches out from one subunit and embraces the other subunit and is responsible for interlocking the two subunits. Our structure explains why flavin reductase P is specific for FMN as cofactor. FMN is recognized and tightly bound by a network of 16 hydrogen bonds, while steric considerations prevent the binding of FAD. A flexible loop containing a Lys and an Arg could account for the NADPH specificity. The structure reveals information about several aspects of the catalytic mechanism. For example, we show that the first step in catalysis, which is hydride transfer from C4 of NADPH to cofactor FMN, involves addition to the re face of the FMN, probably at the N5 position. The limited accessibility of the FMN binding pocket and the extensive FMN-protein hydrogen bond network are consistent with the observed ping-pong bisubstrate--biproduct reaction kinetics. Finally, we propose a model for how flavin reductase P might shuttle electrons between NADPH and luciferase.


    Related Citations: 
    • Crystallization and Preliminary Crystallographic Analysis of Nadph:Fmn Oxidoreductase from Vibrio Harveyi
      Tanner, J.,Lei, B.,Liu, M.,TU, S.C.,Krause, K.L.
      (1994) J.Mol.Biol. 241: 283


    Organizational Affiliation

    Department of Biochemical and Biophysical Sciences, University of Houston, Texas 77204-5934, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
NADPH-FLAVIN OXIDOREDUCTASE
A, B
240Vibrio harveyiGene Names: frp
EC: 1.6.99.-
Find proteins for Q56691 (Vibrio harveyi)
Go to UniProtKB:  Q56691
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

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

Download SDF File 
Download CCD File 
A, B
FLAVIN MONONUCLEOTIDE
RIBOFLAVIN MONOPHOSPHATE
C17 H21 N4 O9 P
FVTCRASFADXXNN-SCRDCRAPSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
FMNKd: 170 nM BINDINGMOAD
FMNKd: 170 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.207 
  • R-Value Work: 0.175 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 51.200α = 90.00
b = 85.900β = 109.30
c = 58.100γ = 90.00
Software Package:
Software NamePurpose
X-PLORphasing
X-PLORrefinement
R-AXISdata scaling
X-PLORmodel building
R-AXISdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-01-13
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance