Experimental Data Snapshot

  • Resolution: 2.70 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.207 

wwPDB Validation   3D Report Full Report

Ligand Structure Quality Assessment 

This is version 1.4 of the entry. See complete history


Crystal structure of a NifS-like protein from Thermotoga maritima: implications for iron sulphur cluster assembly.

Kaiser, J.T.Clausen, T.Bourenkow, G.P.Bartunik, H.D.Steinbacher, S.Huber, R.

(2000) J Mol Biol 297: 451-464

  • DOI: https://doi.org/10.1006/jmbi.2000.3581
  • Primary Citation of Related Structures:  
    1ECX, 1EG5

  • PubMed Abstract: 

    NifS-like proteins are ubiquitous, homodimeric, proteins which belong to the alpha-family of pyridoxal-5'-phoshate dependent enzymes. They are proposed to donate elementary sulphur, generated from cysteine, via a cysteinepersulphide intermediate during iron sulphur cluster biosynthesis, an important albeit not well understood process. Here, we report on the crystal structure of a NifS-like protein from the hyperthermophilic bacterium Thermotoga maritima (tmNifS) at 2.0 A resolution. The tmNifS is structured into two domains, the larger bearing the pyridoxal-5'-phosphate-binding active site, the smaller hosting the active site cysteine in the middle of a highly flexible loop, 12 amino acid residues in length. Once charged with sulphur the loop could possibly deliver S(0) directly to regions far remote from the protein. Based on the three-dimensional structures of the native as well as the substrate complexed form and on spectrophotometric results, a mechanism of sulphur activation is proposed. The His99, which stacks on top of the pyridoxal-5'-phosphate co-factor, is assigned a crucial role during the catalytic cycle by acting as an acid-base catalyst and is believed to have a pK(a) value depending on the co-factor redox state.

  • Organizational Affiliation

    Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Am Klopferspitz 18a, Martinsried, D-82152, Germany.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B
384Thermotoga maritimaMutation(s): 0 
Find proteins for Q9X218 (Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8))
Explore Q9X218 
Go to UniProtKB:  Q9X218
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9X218
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.70 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.207 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 115.41α = 90
b = 115.41β = 90
c = 156.95γ = 120
Software Package:
Software NamePurpose
MOSFLMdata reduction
CCP4data scaling

Structure Validation

View Full Validation Report

Ligand Structure Quality Assessment 

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-03-20
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance
  • Version 1.3: 2018-01-31
    Changes: Advisory, Experimental preparation
  • Version 1.4: 2024-02-07
    Changes: Advisory, Data collection, Database references, Derived calculations