1SX1

Solution NMR Structure and X-ray Absorption Analysis of the C-Terminal Zinc-Binding Domain of the SecA ATPase


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Solution NMR Structure and X-ray Absorption Analysis of the C-Terminal Zinc-Binding Domain of the SecA ATPase.

Dempsey, B.R.Wrona, M.Moulin, J.M.Gloor, G.B.Jalilehvand, F.Lajoie, G.Shaw, G.S.Shilton, B.H.

(2004) Biochemistry 43: 9361-9371

  • DOI: https://doi.org/10.1021/bi0493057
  • Primary Citation of Related Structures:  
    1SX0, 1SX1

  • PubMed Abstract: 

    The solution NMR structure of a 22-residue Zn(2+)-binding domain (ZBD) from Esherichia coli preprotein translocase subunit SecA is presented. In conjunction with X-ray absorption analysis, the NMR structure shows that three cysteines and a histidine in the sequence CXCXSGX(8)CH assume a tetrahedral arrangement around the Zn(2+) atom, with an average Zn(2+)-S bond distance of 2.30 A and a Zn(2+)-N bond distance of 2.03 A. The NMR structure shows that ND1 of His20 binds to the Zn(2+) atom. The ND1-Zn(2+) bond is somewhat strained: it makes an angle of approximately 17 degrees with the plane of the ring, and it also shows a significant "in-plane" distortion of 13 degrees. A comprehensive sequence alignment of the SecA-ZBD from many different organisms shows that, along with the four Zn(2+) ligands, there is a serine residue (Ser12) that is completely conserved. The NMR structure indicates that the side chain of this serine residue forms a strong hydrogen bond with the thiolate of the third cysteine residue (Cys19); therefore, the conserved serine appears to have a critical role in the structure. SecB, an export-specific chaperone, is the only known binding partner for the SecA-ZBD. A phylogenetic analysis using 86 microbial genomes shows that 59 of the organisms carry SecA with a ZBD, but only 31 of these organisms also possess a gene for SecB, indicating that there may be uncharacterized binding partners for the SecA-ZBD.


  • Organizational Affiliation

    Department of Biochemistry, University of Western Ontario, London ON N6A 5C1, Ontario, Canada.


Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
SecA22N/AMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download Ideal Coordinates CCD File 
B [auth A]ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-07-06
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-03-02
    Changes: Database references, Derived calculations
  • Version 1.4: 2024-05-22
    Changes: Data collection