Solution structure of the PX domain, a target of the SH3 domain

Nat Struct Biol. 2001 Jun;8(6):526-30. doi: 10.1038/88591.


The phox homology (PX) domain is a novel protein module containing a conserved proline-rich motif. We have shown that the PX domain isolated from the human p47phox protein, a soluble subunit of phagocyte NADPH oxidase, binds specifically to the C-terminal SH3 domain derived from the same protein. The solution structure of p47 PX has an alpha + beta structure with a novel folding motif topology and reveals that the proline-rich motif is presented on the molecular surface for easy recognition by the SH3 domain. The proline-rich motif of p47 PX in the free state adopts a distorted left-handed polyproline type II helix conformation.

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Binding Sites
  • Conserved Sequence
  • Humans
  • Models, Molecular
  • Molecular Sequence Data
  • NADPH Oxidases / chemistry
  • Nuclear Magnetic Resonance, Biomolecular
  • Phosphoproteins / chemistry*
  • Phosphoproteins / metabolism*
  • Proline / metabolism
  • Protein Binding
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Protein Subunits
  • Proto-Oncogene Proteins pp60(c-src) / chemistry
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism
  • Sequence Alignment
  • src Homology Domains*


  • Phosphoproteins
  • Protein Subunits
  • Recombinant Fusion Proteins
  • Proline
  • NADPH Oxidases
  • neutrophil cytosolic factor 1
  • Proto-Oncogene Proteins pp60(c-src)

Associated data

  • PDB/1GD5