3S6Y

Structure of reovirus attachment protein sigma1 in complex with alpha-2,6-sialyllactose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.79 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.158 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of reovirus attachment protein sigma1 in complex with sialylated oligosaccharides

Reiter, D.M.Frierson, J.M.Halvorson, E.E.Kobayashi, T.Dermody, T.S.Stehle, T.

(2011) Plos Pathog. 7: e1002166-e1002166

  • DOI: 10.1371/journal.ppat.1002166
  • Primary Citation of Related Structures:  3S6X, 3S6Z

  • PubMed Abstract: 
  • Many viruses attach to target cells by binding to cell-surface glycans. To gain a better understanding of strategies used by viruses to engage carbohydrate receptors, we determined the crystal structures of reovirus attachment protein σ1 in complex w ...

    Many viruses attach to target cells by binding to cell-surface glycans. To gain a better understanding of strategies used by viruses to engage carbohydrate receptors, we determined the crystal structures of reovirus attachment protein σ1 in complex with α-2,3-sialyllactose, α-2,6-sialyllactose, and α-2,8-di-siallylactose. All three oligosaccharides terminate in sialic acid, which serves as a receptor for the reovirus serotype studied here. The overall structure of σ1 resembles an elongated, filamentous trimer. It contains a globular head featuring a compact β-barrel, and a fibrous extension formed by seven repeating units of a triple β-spiral that is interrupted near its midpoint by a short α-helical coiled coil. The carbohydrate-binding site is located between β-spiral repeats two and three, distal from the head. In all three complexes, the terminal sialic acid forms almost all of the contacts with σ1 in an identical manner, while the remaining components of the oligosaccharides make little or no contacts. We used this structural information to guide mutagenesis studies to identify residues in σ1 that functionally engage sialic acid by assessing hemagglutination capacity and growth in murine erythroleukemia cells, which require sialic acid binding for productive infection. Our studies using σ1 mutant viruses reveal that residues 198, 202, 203, 204, and 205 are required for functional binding to sialic acid by reovirus. These findings provide insight into mechanisms of reovirus attachment to cell-surface glycans and contribute to an understanding of carbohydrate binding by viruses. They also establish a filamentous, trimeric carbohydrate-binding module that could potentially be used to endow other trimeric proteins with carbohydrate-binding properties.


    Organizational Affiliation

    Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Outer capsid protein sigma-1
A, B, C
325Reovirus type 3 (strain Dearing)Gene Names: S1
Find proteins for P03528 (Reovirus type 3 (strain Dearing))
Go to UniProtKB:  P03528
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BGC
Query on BGC

Download SDF File 
Download CCD File 
A, C
BETA-D-GLUCOSE
C6 H12 O6
WQZGKKKJIJFFOK-VFUOTHLCSA-N
 Ligand Interaction
GAL
Query on GAL

Download SDF File 
Download CCD File 
A, C
BETA-D-GALACTOSE
C6 H12 O6
WQZGKKKJIJFFOK-FPRJBGLDSA-N
 Ligand Interaction
SIA
Query on SIA

Download SDF File 
Download CCD File 
A, B, C
O-SIALIC ACID
C11 H19 N O9
SQVRNKJHWKZAKO-YRMXFSIDSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.79 Å
  • R-Value Free: 0.208 
  • R-Value Work: 0.158 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 87.150α = 90.00
b = 333.180β = 90.00
c = 58.490γ = 90.00
Software Package:
Software NamePurpose
XSCALEdata scaling
AMoREphasing
PHENIXrefinement
XDSdata reduction
PDB_EXTRACTdata extraction
XDSdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-11-23
    Type: Initial release
  • Version 1.1: 2017-10-11
    Type: Data collection
  • Version 1.2: 2018-01-24
    Type: Structure summary