4MAG

Crystal structure of the Periplasmic Sialic Acid Binding Protein from Vibrio Cholerea


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site.

Gangi Setty, T.Cho, C.Govindappa, S.Apicella, M.A.Ramaswamy, S.

(2014) Acta Crystallogr.,Sect.D 70: 1801-1811

  • DOI: 10.1107/S139900471400830X
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the ho ...

    Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.


    Organizational Affiliation

    Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065, India.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Sialic Acid Binding Protein
A
307N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
CO
Query on CO

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Download CCD File 
A
COBALT (II) ION
Co
XLJKHNWPARRRJB-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.182 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 74.977α = 90.00
b = 82.315β = 90.00
c = 119.354γ = 90.00
Software Package:
Software NamePurpose
MAR345dtbdata collection
REFMACrefinement
PDB_EXTRACTdata extraction
d*TREKdata scaling
d*TREKdata reduction
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-07-02
    Type: Initial release
  • Version 1.1: 2014-09-24
    Type: Database references