7B5I | pdb_00007b5i

Cryo-EM structure of the contractile injection system cap complex from Anabaena PCC7120


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 2.80 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report

Validation slider image for 7B5I

This is version 1.3 of the entry. See complete history

Literature

Structure of a thylakoid-anchored contractile injection system in multicellular cyanobacteria.

Weiss, G.L.Eisenstein, F.Kieninger, A.K.Xu, J.Minas, H.A.Gerber, M.Feldmuller, M.Maldener, I.Forchhammer, K.Pilhofer, M.

(2022) Nat Microbiol 7: 386-396

  • DOI: https://doi.org/10.1038/s41564-021-01055-y
  • Primary Citation Related Structures: 
    7B5H, 7B5I

  • PubMed Abstract: 

    Contractile injection systems (CISs) mediate cell-cell interactions by phage tail-like structures, using two distinct modes of action: extracellular CISs are released into the medium, while type 6 secretion systems (T6SSs) are attached to the cytoplasmic membrane and function upon cell-cell contact. Here, we characterized a CIS in the multicellular cyanobacterium Anabaena, with features distinct from extracellular CISs and T6SSs. Cryo-electron tomography of focused ion beam-milled cells revealed that CISs were anchored in thylakoid membrane stacks, facing the cell periphery. Single particle cryo-electron microscopy showed that this unique in situ localization was mediated by extensions of tail fibre and baseplate components. On stress, cyanobacteria induced the formation of ghost cells, presenting thylakoid-anchored CISs to the environment. Functional assays suggest that these CISs may mediate ghost cell formation and/or interactions of ghost cells with other organisms. Collectively, these data provide a framework for understanding the evolutionary re-engineering of CISs and potential roles of these CISs in cyanobacterial programmed cell death.


  • Organizational Affiliation
    • Department of Biology, Institute of Molecular Biology & Biophysics, Eidgenössische Technische Hochschule Zürich, Zurich, Switzerland.

Macromolecule Content 

  • Total Structure Weight: 920.63 kDa 
  • Atom Count: 64,458 
  • Modeled Residue Count: 8,100 
  • Deposited Residue Count: 8,166 
  • Unique protein chains: 4

Macromolecules

Find similar proteins by:|  3D Structure
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
All3327 protein192Nostoc sp. PCC 7120 = FACHB-418Mutation(s): 0 
Find similar proteins by:|  3D Structure
Entity ID: 2
MoleculeChains  Sequence LengthOrganismDetailsImage
All3326 protein399Nostoc sp. PCC 7120 = FACHB-418Mutation(s): 0 
Find similar proteins by:|  3D Structure
Entity ID: 3
MoleculeChains  Sequence LengthOrganismDetailsImage
All3325 protein484Nostoc sp. PCC 7120 = FACHB-418Mutation(s): 0 
Find similar proteins by:|  3D Structure

Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 2.80 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONRELION3.0

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2022-02-23
    Type: Initial release
  • Version 1.1: 2022-03-02
    Changes: Database references
  • Version 1.2: 2022-03-16
    Changes: Database references
  • Version 1.3: 2024-11-20
    Changes: Data collection, Structure summary