7PIK

Cryo-EM structure of E. coli TnsB in complex with right end fragment of Tn7 transposon


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 2.68 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural basis of transposon end recognition explains central features of Tn7 transposition systems.

Kaczmarska, Z.Czarnocki-Cieciura, M.Gorecka-Minakowska, K.M.Wingo, R.J.Jackiewicz, J.Zajko, W.Poznanski, J.T.Rawski, M.Grant, T.Peters, J.E.Nowotny, M.

(2022) Mol Cell 82: 2618

  • DOI: https://doi.org/10.1016/j.molcel.2022.05.005
  • Primary Citation of Related Structures:  
    7PIK

  • PubMed Abstract: 

    Tn7 is a bacterial transposon with relatives containing element-encoded CRISPR-Cas systems mediating RNA-guided transposon insertion. Here, we present the 2.7 Å cryoelectron microscopy structure of prototypic Tn7 transposase TnsB interacting with the transposon end DNA. When TnsB interacts across repeating binding sites, it adopts a beads-on-a-string architecture, where the DNA-binding and catalytic domains are arranged in a tiled and intertwined fashion. The DNA-binding domains form few base-specific contacts leading to a binding preference that requires multiple weakly conserved sites at the appropriate spacing to achieve DNA sequence specificity. TnsB binding imparts differences in the global structure of the protein-bound DNA ends dictated by the spacing or overlap of binding sites explaining functional differences in the left and right ends of the element. We propose a model of the strand-transfer complex in which the terminal TnsB molecule is rearranged so that its catalytic domain is in a position conducive to transposition.


  • Organizational Affiliation

    Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland.


Macromolecules

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Transposon Tn7 transposition protein TnsBA,
B,
C,
D,
G [auth E]
703Escherichia coliMutation(s): 0 
Gene Names: tnsB
UniProt
Find proteins for P13989 (Escherichia coli)
Explore P13989 
Go to UniProtKB:  P13989
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP13989
Sequence Annotations
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  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains LengthOrganismImage
Right end fragment of Tn7 transposonE [auth K]70Escherichia coli
Sequence Annotations
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  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains LengthOrganismImage
Right end fragment of Tn7 transposonF [auth L]70Escherichia coli
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 2.68 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONcryoSPARC3.2
MODEL REFINEMENTPHENIX1.18

Structure Validation

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Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Foundation for Polish SciencePolandPOIR.04.04.00-00-20E7/16-00
European Union (EU)European UnionPOIG.02.02.00-14-024/08-00

Revision History  (Full details and data files)

  • Version 1.0: 2022-06-15
    Type: Initial release
  • Version 1.1: 2022-08-03
    Changes: Database references
  • Version 1.2: 2024-07-17
    Changes: Data collection