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 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 48.58 kDa 
• Atom Count: 3302 
• Modelled Residue Count: 398 
• Deposited Residue Count: 416 
• Unique protein chains: 1

4PUR

Crystal structure of MglA from Francisella tularensis

• PDB DOI: 10.2210/pdb4PUR/pdb

• Classification: TRANSCRIPTION
• Organism(s): Francisella tularensis subsp. tularensis SCHU S4
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2014-03-13 Released: 2015-06-24 
• Deposition Author(s): Cuthbert, B.J., Schumacher, M.A., Brennan, R.G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.95 Å
• R-Value Free: 0.228 
• R-Value Work: 0.172 
• R-Value Observed: 0.178 

Literature

Structural and Biochemical Characterization of the Francisella tularensis Pathogenicity Regulator, Macrophage Locus Protein A (MglA).

Cuthbert, B.J., Brennan, R.G., Schumacher, M.A.

(2015) PLoS One 10: e0128225-e0128225

• PubMed: 26121147 
• DOI: 10.1371/journal.pone.0128225
• Primary Citation of Related Structures:  
  4PUR


• PubMed Abstract: 
  

Francisella tularensis is one of the most infectious bacteria known and is the etiologic agent of tularemia. Francisella virulence arises from a 33 kilobase (Kb) pathogenicity island (FPI) that is regulated by the macrophage locus protein A (MglA) and the stringent starvation protein A (SspA). These proteins interact with both RNA polymerase (RNAP) and the pathogenicity island gene regulator (PigR) to activate FPI transcription. However, the molecular mechanisms involved are not well understood. Indeed, while most bacterial SspA proteins function as homodimers to activate transcription, F. tularensis SspA forms a heterodimer with the MglA protein, which is unique to F. tularensis. To gain insight into MglA function, we performed structural and biochemical studies. The MglA structure revealed that it contains a fold similar to the SspA protein family. Unexpectedly, MglA also formed a homodimer in the crystal. Chemical crosslinking and size exclusion chromatography (SEC) studies showed that MglA is able to self-associate in solution to form a dimer but that it preferentially heterodimerizes with SspA. Finally, the MglA structure revealed malate, which was used in crystallization, bound in an open pocket formed by the dimer, suggesting the possibility that this cleft could function in small molecule ligand binding. The location of this binding region relative to recently mapped PigR and RNAP interacting sites suggest possible roles for small molecule binding in MglA and SspA•MglA function.

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Organizational Affiliation: 

Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina, 27710, United States of America.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Macrophage growth locus, subunit A	A, B	208	Francisella tularensis subsp. tularensis SCHU S4	Mutation(s): 0  Gene Names: FTT_1275, mglA
UniProt
Find proteins for Q5NFG1 (Francisella tularensis subsp. tularensis (strain SCHU S4 / Schu 4)) Explore Q5NFG1  Go to UniProtKB:  Q5NFG1

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MLT	C [auth A], D [auth A]	D-MALATE C4 H6 O5 BJEPYKJPYRNKOW-UWTATZPHSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.95 Å
• R-Value Free: 0.228 
• R-Value Work: 0.172 
• R-Value Observed: 0.178 
• Space Group: P 6₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 104.684	α = 90
b = 104.684	β = 90
c = 100.045	γ = 120

Software Package:

Software Name	Purpose
SCALA	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
ADSC	data collection
MOSFLM	data reduction
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2014-03-13 
• Released Date: 2015-06-24 
Deposition Author(s): Cuthbert, B.J., Schumacher, M.A., Brennan, R.G.

Revision History  

• Version 1.0: 2015-06-24
  Type: Initial release
  
• Version 1.1: 2021-01-13
  Changes: Database references, Derived calculations