2M5X | pdb_00002m5x

Novel method of protein purification for structural research. Example of ultra high resolution structure of SPI-2 inhibitor by X-ray and NMR spectroscopy.


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 17 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report

Validation slider image for 2M5X

This is version 1.3 of the entry. See complete history

Literature

Atomic resolution structure of a protein prepared by non-enzymatic His-tag removal. Crystallographic and NMR study of GmSPI-2 inhibitor.

Kopera, E.Bal, W.Lenarcic Zivkovic, M.Dvornyk, A.Kludkiewicz, B.Grzelak, K.Zhukov, I.Zagorski-Ostoja, W.Jaskolski, M.Krzywda, S.

(2014) PLoS One 9: e106936-e106936

  • DOI: https://doi.org/10.1371/journal.pone.0106936
  • Primary Citation Related Structures: 
    2M5X, 4HGU

  • PubMed Abstract: 

    Purification of suitable quantity of homogenous protein is very often the bottleneck in protein structural studies. Overexpression of a desired gene and attachment of enzymatically cleavable affinity tags to the protein of interest made a breakthrough in this field. Here we describe the structure of Galleria mellonella silk proteinase inhibitor 2 (GmSPI-2) determined both by X-ray diffraction and NMR spectroscopy methods. GmSPI-2 was purified using a new method consisting in non-enzymatic His-tag removal based on a highly specific peptide bond cleavage reaction assisted by Ni(II) ions. The X-ray crystal structure of GmSPI-2 was refined against diffraction data extending to 0.98 Å resolution measured at 100 K using synchrotron radiation. Anisotropic refinement with the removal of stereochemical restraints for the well-ordered parts of the structure converged with R factor of 10.57% and Rfree of 12.91%. The 3D structure of GmSPI-2 protein in solution was solved on the basis of 503 distance constraints, 10 hydrogen bonds and 26 torsion angle restraints. It exhibits good geometry and side-chain packing parameters. The models of the protein structure obtained by X-ray diffraction and NMR spectroscopy are very similar to each other and reveal the same β2αβ fold characteristic for Kazal-family serine proteinase inhibitors.


  • Organizational Affiliation
    • Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.

Macromolecule Content 

  • Total Structure Weight: 4.32 kDa 
  • Atom Count: 300 
  • Modeled Residue Count: 40 
  • Deposited Residue Count: 40 
  • Unique protein chains: 1

Macromolecules

Find similar proteins by:|  3D Structure
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
Silk protease inhibitor 240Galleria mellonellaMutation(s): 0 
UniProt
Find proteins for Q968S7 (Galleria mellonella)
Explore Q968S7 
Go to UniProtKB:  Q968S7
Entity Groups
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ968S7
Sequence Annotations
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Reference Sequence

Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 17 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-03-12
    Type: Initial release
  • Version 1.1: 2015-02-25
    Changes: Database references
  • Version 1.2: 2023-06-14
    Changes: Database references, Other
  • Version 1.3: 2024-10-30
    Changes: Data collection, Database references, Structure summary