alpha-Hemolysin, gamma-hemolysin, and leukocidin from Staphylococcus aureus: distant in sequence but similar in structure

Protein Sci. 1997 Dec;6(12):2631-5. doi: 10.1002/pro.5560061216.


alpha-Hemolysin from Staphylococcus aureus assembles from a water-soluble, monomeric species to a membrane-bound heptamer on the surface of target cells, creating water-filled channels that lead to cell death and lysis. Staphylococcus aureus also produces the gamma-hemolysin and leukocidin toxins, which function as two component toxins in the disruption and lysis of erythrocytes and leukocytes. Analysis of the aligned sequences of alpha-hemolysin, gamma-hemolysin, and leukocidin in the context of the alpha-hemolysin heptamer structure supports the conclusion that even though the level of sequence identity between alpha-hemolysin and the gamma-hemolysin and leukocidin toxins is in the so-called twilight zone, the three-dimensional structures of the protomers are probably conserved. By analogy with alpha-hemolysin, gamma-hemolysin and leukocidin may also form oligomeric, transmembrane channels in which an antiparallel beta-barrel constitutes the primary membrane-embedded domain.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Conserved Sequence
  • Hemolysin Proteins / chemistry*
  • Leukocidins / chemistry*
  • Macromolecular Substances
  • Models, Molecular
  • Molecular Sequence Data
  • Molecular Structure
  • Sequence Alignment
  • Staphylococcus aureus / chemistry*


  • Hemolysin Proteins
  • Leukocidins
  • Macromolecular Substances