Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 38.74 kDa 
• Atom Count: 2789 
• Residue Count: 325 
• Unique protein chains: 1

4IFF

Structural organization of FtsB, a transmembrane protein of the bacterial divisome

• DOI: 10.2210/pdb4IFF/pdb

• Classification: CELL CYCLE
• Organism(s): Bacillus virus phi29, Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2012-12-14 Released: 2013-04-10 
• Deposition Author(s): LaPointe, L.M., Taylor, K.C., Subramaniam, S., Khadria, A., Rayment, I., Senes, A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.256 
• R-Value Work: 0.219 
• R-Value Observed: 0.221 

Literature

Structural Organization of FtsB, a Transmembrane Protein of the Bacterial Divisome.

Lapointe, L.M., Taylor, K.C., Subramaniam, S., Khadria, A., Rayment, I., Senes, A.

(2013) Biochemistry 52: 2574-2585

• PubMed: 23520975 
• DOI: 10.1021/bi400222r
• Primary Citation of Related Structures:  
  4IFF


• PubMed Abstract: 
  

We report the first structural analysis of an integral membrane protein of the bacterial divisome. FtsB is a single-pass membrane protein with a periplasmic coiled coil. Its heterologous association with its partner FtsL represents an essential event for the recruitment of the late components to the division site. Using a combination of mutagenesis, computational modeling, and X-ray crystallography, we determined that FtsB self-associates, and we investigated its structural organization. We found that the transmembrane domain of FtsB homo-oligomerizes through an evolutionarily conserved interaction interface where a polar residue (Gln 16) plays a critical role through the formation of an interhelical hydrogen bond. The crystal structure of the periplasmic domain, solved as a fusion with Gp7, shows that 30 juxta-membrane amino acids of FtsB form a canonical coiled coil. The presence of conserved Gly residue in the linker region suggests that flexibility between the transmembrane and coiled coil domains is functionally important. We hypothesize that the transmembrane helices of FtsB form a stable dimeric core for its association with FtsL into a higher-order oligomer and that FtsL is required to stabilize the periplasmic domain of FtsB, leading to the formation of a complex that is competent for binding to FtsQ, and to their consequent recruitment to the divisome. The study provides an experimentally validated structural model and identifies point mutations that disrupt association, thereby establishing important groundwork for the functional characterization of FtsB in vivo.

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Organizational Affiliation: 

Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison Wisconsin, 53706, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Fusion of phage phi29 Gp7 protein and Cell division protein FtsB	A, B, C, D	86	Bacillus virus phi29, Escherichia coli This entity is chimeric	Mutation(s): 0  Gene Names: 7
Find proteins for P0A6S5 (Escherichia coli (strain K12)) Explore P0A6S5  Go to UniProtKB:  P0A6S5
Find proteins for P13848 (Bacillus phage phi29) Explore P13848  Go to UniProtKB:  P13848

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	A, C	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.256 
• R-Value Work: 0.219 
• R-Value Observed: 0.221 
• Space Group: P 6₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 87.577	α = 90
b = 87.577	β = 90
c = 185.11	γ = 120

Software Package:

Software Name	Purpose
HKL-3000	data collection
PHASER	phasing
REFMAC	refinement
HKL-3000	data reduction
HKL-3000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-12-14 
• Released Date: 2013-04-10 
Deposition Author(s): LaPointe, L.M., Taylor, K.C., Subramaniam, S., Khadria, A., Rayment, I., Senes, A.

Revision History 

• Version 1.0: 2013-04-10
  Type: Initial release
  
• Version 1.1: 2013-05-22
  Changes: Database references
• Version 1.2: 2017-08-02
  Changes: Refinement description, Source and taxonomy