Identification of novel peptide agonists from a random peptide library for a 5-oxo-ETE receptor, a receptor for bioactive lipids

J Pept Sci. 2008 Dec;14(12):1251-8. doi: 10.1002/psc.1064.


A combinatorial peptide library contains an enormous combination of amino acid sequences and drug candidates, but an effective screening strategy to identify a variety of bioactive peptides has yet to be established. In this article, a random hexapeptide library was screened to identify novel peptide ligands for a 5-oxo-ETE receptor (OXER), which is a G-protein-coupled receptor for bioactive lipids, by using an OXER-Gi1alpha fusion protein. We successfully identified 2 hexapeptides-Ac-HMQLYF-NH2 and Ac-HMWLYF-NH(2)-that exhibited agonistic activity. Although the corresponding affinities were relatively low (EC50 values of 146 and 6.7 microM, respectively), the activities were confirmed by other independent cell-based assay methods, namely, intracellular calcium mobilization and cell chemotaxis. This study demonstrates that a combinatorial peptide library may be screened using a [35S]GTPgammaS binding assay with G-protein-coupled receptor (GPCR)-Galpha fusion proteins, in general, and that of peptide ligands can be obtained even for nonpeptide receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ligands
  • Lipids / chemistry
  • Peptide Library*
  • Peptides / chemical synthesis
  • Peptides / chemistry
  • Peptides / pharmacology*
  • Receptors, Eicosanoid / agonists*
  • Receptors, Eicosanoid / chemistry
  • Receptors, Eicosanoid / metabolism
  • Receptors, G-Protein-Coupled / agonists
  • Receptors, G-Protein-Coupled / metabolism


  • Ligands
  • Lipids
  • Peptide Library
  • Peptides
  • Receptors, Eicosanoid
  • Receptors, G-Protein-Coupled