Mapping the binding surface of interleukin-8 complexed with an N-terminal fragment of the type 1 human interleukin-8 receptor

FEBS Lett. 1994 Jan 24;338(1):93-7. doi: 10.1016/0014-5793(94)80123-1.

Abstract

Interleukin-8 and its receptors are key mediators of immune and inflammatory responses. Heteronuclear NMR spectroscopy has been utilized to map the binding surface on interleukin-8 (IL-8) for an N-terminal fragment of the human Type-1 IL-8 receptor. A peptide corresponding to residues 1-40 of the IL-8 type 1 receptor (IL8-r1) was titrated into a sample of uniformly 15N-labeled IL-8. IL8-r1 binds to IL-8 with a dissociation constant of 170 +/- 50 microM assuming the peptide binds with a stoichiometry of one peptide per IL-8 monomer, exchanges rapidly (> 900 s-1) between free and bound states, and selectively perturbs the chemical environment of several IL-8 residues. The binding surface on IL-8 suggested by our results is comprised of residues in strand beta 3 of the beta-sheet (Glu48 to Cys50), the turn preceding beta 3 (Ser44), the C-terminal alpha-helix (Val61) and the irregular N-terminal loop region (Thr12, Lys15, Phe17, His18, Lys20 and Phe21). The IL-8 dimer appears to present two symmetrical binding surfaces for the IL8-r1 peptide, suggesting two receptor peptides may bind per dimer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Humans
  • Interleukin-8 / chemistry
  • Interleukin-8 / metabolism*
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Sequence Data
  • Receptors, Interleukin / chemistry
  • Receptors, Interleukin / metabolism*
  • Receptors, Interleukin-8A
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism

Substances

  • Interleukin-8
  • Receptors, Interleukin
  • Receptors, Interleukin-8A
  • Recombinant Proteins