Structure-function studies in a series of carboxyl-terminal octapeptide analogues of anaphylatoxin C5a

J Med Chem. 1992 Jan 24;35(2):220-3. doi: 10.1021/jm00080a004.


The synthesis and structure-activity relationships of C-terminal octapeptide analogues of anaphylatoxin C5a have been studied. The introduction of hydrophobic amino acids into the N-acetylated native octapeptide (N-Ac-His-Lys-Asp-Met-Gln-Leu-Gly-Arg-OH) (1) has led to an analogue with 100 times more activity than the native octapeptide in inhibiting the binding of 125I-labeled anaphylatoxin C5a to human neutrophil membrane receptors. The observed apparent binding Ki's for the compounds (8-10) are in the range of 1-3 microM, and they possess nearly full agonist activity, despite the fact that these analogues are one-eighth or -ninth the size of the natural ligand anaphylatoxin C5a.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding, Competitive
  • Chemotaxis, Leukocyte / drug effects
  • Complement C5a / metabolism*
  • Humans
  • In Vitro Techniques
  • Molecular Sequence Data
  • Neutrophils / drug effects
  • Neutrophils / immunology*
  • Oligopeptides / metabolism
  • Oligopeptides / pharmacology
  • Receptor, Anaphylatoxin C5a
  • Receptors, Complement / metabolism*
  • Sequence Homology, Nucleic Acid
  • Structure-Activity Relationship


  • Oligopeptides
  • Receptor, Anaphylatoxin C5a
  • Receptors, Complement
  • Complement C5a