3ZIH

Bacillus subtilis SepF, C-terminal domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.188 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural and Genetic Analyses Reveal the Protein Sepf as a New Membrane Anchor for the Z Ring.

Duman, R.Ishikawa, S.Celik, I.Strahl, H.Ogasawara, N.Troc, P.Lowe, J.Hamoen, L.W.

(2013) Proc Natl Acad Sci U S A 110: E4601

  • DOI: 10.1073/pnas.1313978110
  • Primary Citation of Related Structures:  
    3ZIE, 3ZIG, 3ZIH, 3ZII

  • PubMed Abstract: 
  • A key step in bacterial cell division is the polymerization of the tubulin homolog FtsZ at midcell. FtsZ polymers are anchored to the cell membrane by FtsA and are required for the assembly of all other cell division proteins. In Gram-positive and cyanobacteria, FtsZ filaments are aligned by the protein SepF, which in vitro polymerizes into large rings that bundle FtsZ filaments ...

    A key step in bacterial cell division is the polymerization of the tubulin homolog FtsZ at midcell. FtsZ polymers are anchored to the cell membrane by FtsA and are required for the assembly of all other cell division proteins. In Gram-positive and cyanobacteria, FtsZ filaments are aligned by the protein SepF, which in vitro polymerizes into large rings that bundle FtsZ filaments. Here we describe the crystal structure of the only globular domain of SepF, located within the C-terminal region. Two-hybrid data revealed that this domain comprises the FtsZ binding site, and EM analyses showed that it is sufficient for ring formation, which is explained by the filaments in the crystals of SepF. Site-directed mutagenesis, gel filtration, and analytical ultracentrifugation indicated that dimers form the basic units of SepF filaments. High-resolution structured illumination microscopy suggested that SepF is membrane associated, and it turned out that purified SepF not only binds to lipid membranes, but also recruits FtsZ. Further genetic and biochemical analyses showed that an amphipathic helix at the N terminus functions as the membrane-binding domain, making SepF a unique membrane anchor for the FtsZ ring. This clarifies why Bacillus subtilis grows without FtsA or the putative membrane anchor EzrA and why bacteria lacking FtsA contain SepF homologs. Both FtsA and SepF use an amphipathic helix for membrane binding. These helices prefer positively curved membranes due to relaxed lipid density; therefore this type of membrane anchor may assist in keeping the Z ring positioned at the strongly curved leading edge of the developing septum.


    Organizational Affiliation

    Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CELL DIVISION PROTEIN SEPFA, B95Bacillus subtilisMutation(s): 0 
UniProt
Find proteins for O31728 (Bacillus subtilis (strain 168))
Explore O31728 
Go to UniProtKB:  O31728
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO31728
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.188 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 40.456α = 90
b = 40.456β = 90
c = 170.331γ = 120
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-11-27
    Type: Initial release
  • Version 1.1: 2013-12-11
    Changes: Database references
  • Version 1.2: 2018-01-24
    Changes: Source and taxonomy