3MMC

Structure of the dissimilatory sulfite reductase from Archaeoglobus fulgidus


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.04 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure of the dissimilatory sulfite reductase from the hyperthermophilic archaeon Archaeoglobus fulgidus.

Schiffer, A.Parey, K.Warkentin, E.Diederichs, K.Huber, H.Stetter, K.O.Kroneck, P.M.Ermler, U.

(2008) J.Mol.Biol. 379: 1063-1074

  • DOI: 10.1016/j.jmb.2008.04.027
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Conservation of energy based on the reduction of sulfate is of fundamental importance for the biogeochemical sulfur cycle. A key enzyme of this ancient anaerobic process is the dissimilatory sulfite reductase (dSir), which catalyzes the six-electron ...

    Conservation of energy based on the reduction of sulfate is of fundamental importance for the biogeochemical sulfur cycle. A key enzyme of this ancient anaerobic process is the dissimilatory sulfite reductase (dSir), which catalyzes the six-electron reduction of sulfite to hydrogen sulfide under participation of a unique magnetically coupled siroheme-[4Fe-4S] center. We determined the crystal structure of the enzyme from the sulfate-reducing archaeon Archaeoglobus fulgidus at 2-A resolution and compared it with that of the phylogenetically related assimilatory Sir (aSir). dSir is organized as a heterotetrameric (alphabeta)(2) complex composed of two catalytically independent alphabeta heterodimers. In contrast, aSir is a monomeric protein built of two fused modules that are structurally related to subunits alpha and beta except for a ferredoxin domain inserted only into the subunits of dSir. The [4Fe-4S] cluster of this ferredoxin domain is considered as the terminal redox site of the electron transfer pathway to the siroheme-[4Fe-4S] center in dSir. While aSir binds one siroheme-[4Fe-4S] center, dSir harbors two of them within each alphabeta heterodimer. Surprisingly, only one siroheme-[4Fe-4S] center in each alphabeta heterodimer is catalytically active, whereas access to the second one is blocked by a tryptophan residue. The spatial proximity of the functional and structural siroheme-[4Fe-4S] centers suggests that the catalytic activity at one active site was optimized during evolution at the expense of the enzymatic competence of the other. The sulfite binding mode and presumably the mechanism of sulfite reduction appear to be largely conserved between dSir and aSir. In addition, a scenario for the evolution of Sirs is proposed.


    Organizational Affiliation

    Fachbereich Biologie, Mathematisch-Naturwissenschaftliche Sektion, Universit├Ąt Konstanz, D-78457 Konstanz, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Sulfite reductase, dissimilatory-type subunit alpha
A, D
418Archaeoglobus fulgidus (strain ATCC 49558 / VC-16 / DSM 4304 / JCM 9628 / NBRC 100126)Mutation(s): 0 
Gene Names: dsrA
EC: 1.8.99.5
Find proteins for Q59109 (Archaeoglobus fulgidus (strain ATCC 49558 / VC-16 / DSM 4304 / JCM 9628 / NBRC 100126))
Go to UniProtKB:  Q59109
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Sulfite reductase, dissimilatory-type subunit beta
B, E
366Archaeoglobus fulgidus (strain ATCC 49558 / VC-16 / DSM 4304 / JCM 9628 / NBRC 100126)Mutation(s): 0 
Gene Names: dsrB
EC: 1.8.99.5
Find proteins for Q59110 (Archaeoglobus fulgidus (strain ATCC 49558 / VC-16 / DSM 4304 / JCM 9628 / NBRC 100126))
Go to UniProtKB:  Q59110
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SF4
Query on SF4

Download SDF File 
Download CCD File 
A, B, D, E
IRON/SULFUR CLUSTER
Fe4 S4
LJBDFODJNLIPKO-VKOJMFJBAC
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
SRM
Query on SRM

Download SDF File 
Download CCD File 
A, B, D, E
SIROHEME
C42 H42 Fe N4 O16
PGYXHNRRBJLFEV-NBUGCWMUSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.04 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.186 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 94.910α = 90.00
b = 69.260β = 107.00
c = 147.210γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
HKL-2000data reduction
XDSdata scaling
HKL-2000data collection
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-05-12
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Refinement description, Version format compliance