Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | 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)

Macromolecule Content

• Total Structure Weight: 35.61 kDa 
• Atom Count: 2218 
• Modelled Residue Count: 245 
• Deposited Residue Count: 292 
• Unique protein chains: 1

4NB1

Crystal Structure of FosB from Staphylococcus aureus at 1.80 Angstrom Resolution with L-Cysteine-Cys9 Disulfide

• PDB DOI: 10.2210/pdb4NB1/pdb

• Classification: TRANSFERASE
• Organism(s): Staphylococcus aureus subsp. aureus N315
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2013-10-22 Released: 2014-02-26 
• Deposition Author(s): Cook, P.D., Thompson, M.K., Goodman, M.C., Jagessar, K., Harp, J., Keithly, M.E., Armstrong, R.N.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.243 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 

Literature

Structure and Function of the Genomically Encoded Fosfomycin Resistance Enzyme, FosB, from Staphylococcus aureus.

Thompson, M.K., Keithly, M.E., Goodman, M.C., Hammer, N.D., Cook, P.D., Jagessar, K.L., Harp, J., Skaar, E.P., Armstrong, R.N.

(2014) Biochemistry 53: 755-765

• PubMed: 24447055 
• DOI: 10.1021/bi4015852
• Primary Citation of Related Structures:  
  4NAY, 4NAZ, 4NB0, 4NB1, 4NB2


• PubMed Abstract: 
  

The Gram-positive pathogen Staphylococcus aureus is a leading cause of global morbidity and mortality. Like many multi-drug-resistant organisms, S. aureus contains antibiotic-modifying enzymes that facilitate resistance to a multitude of antimicrobial compounds. FosB is a Mn(2+)-dependent fosfomycin-inactivating enzyme found in S. aureus that catalyzes nucleophilic addition of either l-cysteine (l-Cys) or bacillithiol (BSH) to the antibiotic, resulting in a modified compound with no bactericidal properties. The three-dimensional X-ray crystal structure of FosB from S. aureus (FosB(Sa)) has been determined to a resolution of 1.15 Å. Cocrystallization of FosB(Sa) with either l-Cys or BSH results in a disulfide bond between the exogenous thiol and the active site Cys9 of the enzyme. An analysis of the structures suggests that a highly conserved loop region of the FosB enzymes must change conformation to bind fosfomycin. While two crystals of FosB(Sa) contain Zn(2+) in the active site, kinetic analyses of FosB(Sa) indicated that the enzyme is inhibited by Zn(2+) for l-Cys transferase activity and only marginally active for BSH transferase activity. Fosfomycin-treated disk diffusion assays involving S. aureus Newman and the USA300 JE2 methicillin-resistant S. aureus demonstrate a marked increase in the sensitivity of the organism to the antibiotic in either the BSH or FosB null strains, indicating that both are required for survival of the organism in the presence of the antibiotic. This work identifies FosB as a primary fosfomycin-modifying pathway of S. aureus and establishes the enzyme as a potential therapeutic target for increased efficacy of fosfomycin against the pathogen.

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Organizational Affiliation: 

Department of Biochemistry, Vanderbilt University School of Medicine , Nashville, Tennessee 37232, United States.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Metallothiol transferase FosB	A, B	146	Staphylococcus aureus subsp. aureus N315	Mutation(s): 0  Gene Names: fosB, SA2124 EC: 2.5.1
UniProt
Find proteins for P60864 (Staphylococcus aureus (strain N315)) Explore P60864  Go to UniProtKB:  P60864

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CYS	C [auth B], E [auth B]	CYSTEINE C3 H7 N O2 S XUJNEKJLAYXESH-REOHCLBHSA-N
SO4	D [auth B]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.243 
• R-Value Work: 0.195 
• R-Value Observed: 0.197 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 40.879	α = 61.19
b = 44.924	β = 65.04
c = 46.348	γ = 82.5

Software Package:

Software Name	Purpose
XSCALE	data scaling
PHASER	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction
PROTEUM PLUS	data collection

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-10-22 
• Released Date: 2014-02-26 
Deposition Author(s): Cook, P.D., Thompson, M.K., Goodman, M.C., Jagessar, K., Harp, J., Keithly, M.E., Armstrong, R.N.

Revision History  

• Version 1.0: 2014-02-26
  Type: Initial release
  
• Version 1.1: 2014-04-16
  Changes: Structure summary