Crystal structure of hemoglobin protease, a heme binding autotransporter protein from pathogenic Escherichia coli

J Biol Chem. 2005 Apr 29;280(17):17339-45. doi: 10.1074/jbc.M412885200. Epub 2005 Feb 22.


The acquisition of iron is essential for the survival of pathogenic bacteria, which have consequently evolved a wide variety of uptake systems to extract iron and heme from host proteins such as hemoglobin. Hemoglobin protease (Hbp) was discovered as a factor involved in the symbiosis of pathogenic Escherichia coli and Bacteroides fragilis, which cause intra-abdominal abscesses. Released from E. coli, this serine protease autotransporter degrades hemoglobin and delivers heme to both bacterial species. The crystal structure of the complete passenger domain of Hbp (110 kDa) is presented, which is the first structure from this class of serine proteases and the largest parallel beta-helical structure yet solved.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bacterial Proteins / chemistry
  • Biological Transport
  • Catalytic Domain
  • Cattle
  • Cloning, Molecular
  • Crystallography, X-Ray
  • Electrons
  • Endopeptidases / chemistry*
  • Endopeptidases / metabolism
  • Escherichia coli / metabolism
  • Heme / chemistry*
  • Hemoglobins / chemistry
  • Models, Molecular
  • Molecular Sequence Data
  • Plasmids / metabolism
  • Polymerase Chain Reaction
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid
  • Serine Endopeptidases / chemistry


  • Bacterial Proteins
  • Hemoglobins
  • Heme
  • Endopeptidases
  • Serine Endopeptidases
  • hemoglobin protease Hbp

Associated data

  • PDB/1WXR