Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 10-mer - A10 

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

Macromolecule Content

• Total Structure Weight: 142.04 kDa 
• Atom Count: 11181 
• Residue Count: 1269 
• Unique protein chains: 2

4BHU

Crystal structure of BslA - A bacterial hydrophobin

• DOI: 10.2210/pdb4BHU/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Bacillus subtilis subsp. subtilis NCIB 3610 = ATCC 6051
• Expression System: Escherichia coli B
• Mutation(s): Yes 


• Deposited: 2013-04-08 Released: 2013-08-14 
• Deposition Author(s): Rao, F.V., Hobley, L., Ostrowski, A., Bromley, K.M., Porter, M., Prescott, A.R., Swedlow, J.R., MacPhee, C.E., van Aalten, D.M.F., Stanley-Wall, N.R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.91 Å
• R-Value Free: 0.199 
• R-Value Work: 0.165 
• R-Value Observed: 0.167 

Literature

Bsla is a Self-Assembling Bacterial Hydrophobin that Coats the Bacillus Subtilis Biofilm.

Hobley, L., Ostrowski, A., Rao, F.V., Bromley, K.M., Porter, M., Prescott, A.R., Macphee, C.E., Van Aalten, D.M.F., Stanley-Wall, N.R.

(2013) Proc Natl Acad Sci U S A 110: 13600

• PubMed: 23904481 
• DOI: 10.1073/pnas.1306390110
• Structures With Same Primary Citation


• PubMed Abstract: 
  

Biofilms represent the predominant mode of microbial growth in the natural environment. Bacillus subtilis is a ubiquitous Gram-positive soil bacterium that functions as an effective plant growth-promoting agent. The biofilm matrix is composed of an exopolysaccharide and an amyloid fiber-forming protein, TasA, and assembles with the aid of a small secreted protein, BslA. Here we show that natively synthesized and secreted BslA forms surface layers around the biofilm. Biophysical analysis demonstrates that BslA can self-assemble at interfaces, forming an elastic film. Molecular function is revealed from analysis of the crystal structure of BslA, which consists of an Ig-type fold with the addition of an unusual, extremely hydrophobic "cap" region. A combination of in vivo biofilm formation and in vitro biophysical analysis demonstrates that the central hydrophobic residues of the cap are essential to allow a hydrophobic, nonwetting biofilm to form as they control the surface activity of the BslA protein. The hydrophobic cap exhibits physiochemical properties remarkably similar to the hydrophobic surface found in fungal hydrophobins; thus, BslA is a structurally defined bacterial hydrophobin. We suggest that biofilms formed by other species of bacteria may have evolved similar mechanisms to provide protection to the resident bacterial community.

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Organizational Affiliation: 

Division of Molecular Microbiology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
UNCHARACTERIZED PROTEIN YUAB	A, B, C, D, E, F, G, H, J	130	Bacillus subtilis subsp. subtilis NCIB 3610 = ATCC 6051	Mutation(s): 1
Find proteins for P71014 (Bacillus subtilis (strain 168)) Go to UniProtKB:  P71014

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
UNCHARACTERIZED PROTEIN YUAB	I	130	Bacillus subtilis subsp. subtilis NCIB 3610 = ATCC 6051	Mutation(s): 1
Find proteins for P71014 (Bacillus subtilis (strain 168)) Go to UniProtKB:  P71014

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	A, B, E, F, J	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
CL	A, B, C, E, F, H, I	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Modified Residues  2 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MLY	A,B,C,D,E,F,G,H,J, I	L-PEPTIDE LINKING	C8 H18 N2 O2		LYS
MSE	A,B,C,D,E,F,G,H,J, I	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.91 Å
• R-Value Free: 0.199 
• R-Value Work: 0.165 
• R-Value Observed: 0.167 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 69.7	α = 90
b = 95.98	β = 90
c = 259.81	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
XDS	data reduction
SCALA	data scaling
PHENIX	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-04-08 
• Released Date: 2013-08-14 
Deposition Author(s): Rao, F.V., Hobley, L., Ostrowski, A., Bromley, K.M., Porter, M., Prescott, A.R., Swedlow, J.R., MacPhee, C.E., van Aalten, D.M.F., Stanley-Wall, N.R.

Revision History 

• Version 1.0: 2013-08-14
  Type: Initial release
  
• Version 1.1: 2013-08-28
  Changes: Database references