RCSB PDB - 4GLY: Human urokinase-type plasminogen activator uPA in complex with the two-disulfide bridge peptide UK504 (original) (raw)
Bicyclic Peptide Ligands Pulled out of Cysteine-Rich Peptide Libraries.
[Chen, S.](/search?q=citation.rcsb%5Fauthors:Chen, S.), [Rentero Rebollo, I.](/search?q=citation.rcsb%5Fauthors:Rentero Rebollo, I.), [Buth, S.A.](/search?q=citation.rcsb%5Fauthors:Buth, S.A.), [Morales-Sanfrutos, J.](/search?q=citation.rcsb%5Fauthors:Morales-Sanfrutos, J.), [Touati, J.](/search?q=citation.rcsb%5Fauthors:Touati, J.), [Leiman, P.G.](/search?q=citation.rcsb%5Fauthors:Leiman, P.G.), [Heinis, C.](/search?q=citation.rcsb%5Fauthors:Heinis, C.)
(2013) J Am Chem Soc 135: 6562-6569
PubMed: 23560397 Search on PubMed
PubMed Abstract:
Bicyclic peptide ligands were found to have good binding affinity and target specificity. However, the method applied to generate bicyclic ligands based on phage-peptide alkylation is technically complex and limits its application to specialized laboratories. Herein, we report a method that involves a simpler and more robust procedure that additionally allows screening of structurally more diverse bicyclic peptide libraries. In brief, phage-encoded combinatorial peptide libraries of the format X(m)CX(n)CX(o)CX(p) are oxidized to connect two pairs of cysteines (C). This allows the generation of 3 × (m + n + o + p) different peptide topologies because the fourth cysteine can appear in any of the (m + n + o + p) randomized amino acid positions (X). Panning of such libraries enriched strongly peptides with four cysteines and yielded tight binders to protein targets. X-ray structure analysis revealed an important structural role of the disulfide bridges. In summary, the presented approach offers facile access to bicyclic peptide ligands with good binding affinities.
Organizational Affiliation:
Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.