5LDF

Maltose binding protein genetically fused to dodecameric glutamine synthetase


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 6.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 2.1 of the entry. See complete history


Literature

Fusion to a homo-oligomeric scaffold allows cryo-EM analysis of a small protein.

Coscia, F.Estrozi, L.F.Hans, F.Malet, H.Noirclerc-Savoye, M.Schoehn, G.Petosa, C.

(2016) Sci Rep 6: 30909-30909

  • DOI: https://doi.org/10.1038/srep30909
  • Primary Citation of Related Structures:  
    5LDF

  • PubMed Abstract: 

    Recent technical advances have revolutionized the field of cryo-electron microscopy (cryo-EM). However, most monomeric proteins remain too small (<100 kDa) for cryo-EM analysis. To overcome this limitation, we explored a strategy whereby a monomeric target protein is genetically fused to a homo-oligomeric scaffold protein and the junction optimized to allow the target to adopt the scaffold symmetry, thereby generating a chimeric particle suitable for cryo-EM. To demonstrate the concept, we fused maltose-binding protein (MBP), a 40 kDa monomer, to glutamine synthetase, a dodecamer formed by two hexameric rings. Chimeric constructs with different junction lengths were screened by biophysical analysis and negative-stain EM. The optimal construct yielded a cryo-EM reconstruction that revealed the MBP structure at sub-nanometre resolution. These findings illustrate the feasibility of using homo-oligomeric scaffolds to enable cryo-EM analysis of monomeric proteins, paving the way for applying this strategy to challenging structures resistant to crystallographic and NMR analysis.


  • Organizational Affiliation

    Institut de Biologie Structurale (IBS), Univ. Grenoble Alpes, CEA, CNRS, 38044 Grenoble, France.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Glutamine synthetase
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J, K, L
466Salmonella enterica subsp. enterica serovar TyphiMutation(s): 0 
Gene Names: glnASTY3874t3614
EC: 6.3.1.2
UniProt
Find proteins for P0A1P7 (Salmonella typhi)
Explore P0A1P7 
Go to UniProtKB:  P0A1P7
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0A1P7
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Maltose-binding periplasmic protein
M, N, O, P, Q
M, N, O, P, Q, R, S, T, U, V, W, X
370Escherichia coli O157:H7Mutation(s): 0 
Gene Names: malEZ5632ECs5017
UniProt
Find proteins for P0AEY0 (Escherichia coli O157:H7)
Explore P0AEY0 
Go to UniProtKB:  P0AEY0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0AEY0
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 6.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONRELION

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Nanosciences FoundationFrance--

Revision History  (Full details and data files)

  • Version 1.0: 2016-08-10
    Type: Initial release
  • Version 1.1: 2017-08-02
    Changes: Data collection, Derived calculations
  • Version 1.2: 2018-11-21
    Changes: Advisory, Data collection, Derived calculations
  • Version 1.3: 2019-10-02
    Changes: Data collection, Other
  • Version 1.4: 2019-10-23
    Changes: Data collection, Other
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Non-polymer description, Source and taxonomy, Structure summary
  • Version 2.1: 2024-05-15
    Changes: Data collection, Database references, Structure summary