Central ions and lateral asparagine/glutamine zippers stabilize the post-fusion hairpin conformation of the SARS coronavirus spike glycoprotein

Virology. 2005 May 10;335(2):276-85. doi: 10.1016/j.virol.2005.02.022.

Abstract

The coronavirus spike glycoprotein is a class I membrane fusion protein with two characteristic heptad repeat regions (HR1 and HR2) in its ectodomain. Here, we report the X-ray structure of a previously characterized HR1/HR2 complex of the severe acute respiratory syndrome coronavirus spike protein. As expected, the HR1 and HR2 segments are organized in antiparallel orientations within a rod-like molecule. The HR1 helices form an exceptionally long (120 A) internal coiled coil stabilized by hydrophobic and polar interactions. A striking arrangement of conserved asparagine and glutamine residues of HR1 propagates from two central chloride ions, providing hydrogen-bonding "zippers" that strongly constrain the path of the HR2 main chain, forcing it to adopt an extended conformation at either end of a short HR2 alpha-helix.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Asparagine / metabolism*
  • Glutamine / metabolism*
  • Ions / chemistry
  • Ions / metabolism
  • Membrane Fusion / physiology*
  • Membrane Glycoproteins / chemistry*
  • Membrane Glycoproteins / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Binding
  • Protein Conformation
  • Salts / chemistry
  • Salts / metabolism
  • Severe acute respiratory syndrome-related coronavirus / chemistry*
  • Severe acute respiratory syndrome-related coronavirus / metabolism*
  • Spike Glycoprotein, Coronavirus
  • Static Electricity
  • Thermodynamics
  • Viral Envelope Proteins / chemistry*
  • Viral Envelope Proteins / metabolism*

Substances

  • Ions
  • Membrane Glycoproteins
  • Salts
  • Spike Glycoprotein, Coronavirus
  • Viral Envelope Proteins
  • spike glycoprotein, SARS-CoV
  • Glutamine
  • Asparagine

Associated data

  • PDB/1WYY