Reconstructing the discontinuous and conformational β1/β3-loop binding site on hFSH/hCG by using highly constrained
Linde E J Smeenk1, Drohpatie Timmers-Parohi, Joris J Benschop
1Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands).
Chembiochem : a European Journal of Chemical Biology
|December 4, 2014
Summary
Researchers developed a new technology to create peptide molecules that mimic protein binding sites. This method successfully generated mimics for human follicle-stimulating hormone (hFSH) and human chorionic gonadotropin (hCG), showing enhanced binding capabilities.
Area of Science:
- Biomedical Sciences
- Chemical Biology
- Protein Engineering
Background:
- Mimicking protein functional sites with peptides is difficult.
- Constrained and discontinuous peptide structures are challenging to synthesize.
Purpose of the Study:
- To develop a robust technology for creating constrained, discontinuous peptide binding site mimics.
- To demonstrate the technology's application on complex protein targets like hFSH and hCG.
Main Methods:
- Covalent assembly using Ar(CH2Br)2-promoted peptide cyclizations.
- Incorporation of oxime ligation and disulfide bond formation.
- Application to unprotected side chain groups and various peptide lengths.
Main Results:
- A tetracyclic mimic for hFSH demonstrated over 600-fold improved binding compared to controls.
- A tricyclic mimic for hCG showed binding affinity to anti-hCG mAb 8G5 comparable to hCG itself.
- This hCG mimic exhibited specific binding to an hCG-neutralizing antibody (mAb 3468), unlike linear or monocyclic controls.
Conclusions:
- The developed technology enables the synthesis of highly constrained and discontinuous peptide mimics.
- This approach is effective for complex protein targets like Cys-knot proteins.
- The peptide mimics show potential for therapeutic and diagnostic applications in targeting hormones like FSH and hCG.
