3GBG | pdb_00003gbg

Crystal Structure of ToxT from Vibrio Cholerae O395

• PDB DOI: https://doi.org/10.2210/pdb3GBG/pdb

• Classification: transcription regulator
• Organism(s): Vibrio cholerae O395
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2009-02-19 Released: 2010-02-23 
• Deposition Author(s): Lowden, M.J., Kull, F.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 
  0.245 (Depositor), 0.245 (DCC) 
• R-Value Work: 
  0.214 (Depositor), 0.213 (DCC) 
• R-Value Observed: 
  0.214 (Depositor) 

Starting Model: experimental

Literature

Structure of Vibrio cholerae ToxT reveals a mechanism for fatty acid regulation of virulence genes.

Lowden, M.J., Skorupski, K., Pellegrini, M., Chiorazzo, M.G., Taylor, R.K., Kull, F.J.

(2010) Proc Natl Acad Sci U S A 107: 2860-2865

• PubMed: 20133655 
• DOI: https://doi.org/10.1073/pnas.0915021107
• Primary Citation Related Structures: 
  3GBG


• PubMed Abstract: 
  

  Cholera is an acute intestinal infection caused by the bacterium Vibrio cholerae. In order for V. cholerae to cause disease, it must produce two virulence factors, the toxin-coregulated pilus (TCP) and cholera toxin (CT), whose expression is controlled by a transcriptional cascade culminating with the expression of the AraC-family regulator, ToxT. We have solved the 1.9 A resolution crystal structure of ToxT, which reveals folds in the N- and C-terminal domains that share a number of features in common with AraC, MarA, and Rob as well as the unexpected presence of a buried 16-carbon fatty acid, cis-palmitoleate. The finding that cis-palmitoleic acid reduces TCP and CT expression in V. cholerae and prevents ToxT from binding to DNA in vitro provides a direct link between the host environment of V. cholerae and regulation of virulence gene expression.

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Organizational Affiliation: 
• Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, NH 03755, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content 

• Total Structure Weight: 32.35 kDa 
• Atom Count: 2,360 
• Modeled Residue Count: 260 
• Deposited Residue Count: 276 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
TCP pilus virulence regulatory protein	A	276	Vibrio cholerae O395	Mutation(s): 0  Gene Names: tcpN, toxT, VC0395_A0363
UniProt
Find proteins for A5F384 (Vibrio cholerae serotype O1 (strain ATCC 39541 / Classical Ogawa 395 / O395)) Explore A5F384  Go to UniProtKB:  A5F384

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PAM	B [auth A]	PALMITOLEIC ACID C16 H30 O2 SECPZKHBENQXJG-FPLPWBNLSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free:  0.245 (Depositor), 0.245 (DCC) 
• R-Value Work:  0.214 (Depositor), 0.213 (DCC) 
• R-Value Observed: 0.214 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 39.311	α = 90
b = 77.739	β = 90
c = 83.568	γ = 90

Software Package:

Software Name	Purpose
SOLVE	phasing
CNS	refinement
XDS	data reduction
XSCALE	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2010-02-23 
Deposition Author(s): Lowden, M.J., Kull, F.J.

Revision History  

• Version 1.0: 2010-02-23
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Source and taxonomy, Version format compliance
• Version 1.2: 2024-02-21
  Changes: Data collection, Database references, Derived calculations
• Version 1.3: 2024-04-03
  Changes: Refinement description