Novel beta-barrel fold in the nuclear magnetic resonance structure of the replicase nonstructural protein 1 from the severe acute respiratory syndrome coronavirus

J Virol. 2007 Apr;81(7):3151-61. doi: 10.1128/JVI.01939-06. Epub 2007 Jan 3.

Abstract

The nonstructural protein 1 (nsp1) of the severe acute respiratory syndrome coronavirus has 179 residues and is the N-terminal cleavage product of the viral replicase polyprotein that mediates RNA replication and processing. The specific function of nsp1 is not known. Here we report the nuclear magnetic resonance structure of the nsp1 segment from residue 13 to 128, which represents a novel alpha/beta-fold formed by a mixed parallel/antiparallel six-stranded beta-barrel, an alpha-helix covering one opening of the barrel, and a 3(10)-helix alongside the barrel. We further characterized the full-length 179-residue protein and show that the polypeptide segments of residues 1 to 12 and 129 to 179 are flexibly disordered. The structure is analyzed in a search for possible correlations with the recently reported activity of nsp1 in the degradation of mRNA.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Models, Molecular
  • Molecular Sequence Data
  • Nuclear Magnetic Resonance, Biomolecular
  • Peptide Fragments / chemistry
  • Peptide Fragments / genetics
  • Peptide Fragments / metabolism
  • Protein Folding*
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • RNA Replicase / chemistry*
  • RNA Replicase / genetics
  • RNA Replicase / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • SARS Virus / enzymology*
  • SARS Virus / genetics
  • Viral Nonstructural Proteins / chemistry*
  • Viral Nonstructural Proteins / genetics
  • Viral Nonstructural Proteins / metabolism*

Substances

  • Peptide Fragments
  • Recombinant Proteins
  • Viral Nonstructural Proteins
  • RNA Replicase

Associated data

  • PDB/2GDT
  • PDB/2HSX