Double Strain-Promoted Macrocyclization for the Rapid Selection of Cell-Active Stapled Peptides.

ABSTRACT: Peptide stapling is a method for designing macrocyclic alpha-helical inhibitors of protein-protein interactions. However, obtaining a cell-active inhibitor can require significant optimization. We report a novel stapling technique based on a double strain-promoted azide-alkyne reaction, and exploit its biocompatibility to accelerate the discovery of cell-active stapled peptides. As a proof of concept, MDM2-binding peptides were stapled in parallel, directly in cell culture medium in 96-well plates, and simultaneously evaluated in a p53 reporter assay. This in?situ stapling/screening process gave an optimal candidate that showed improved proteolytic stability and nanomolar binding to MDM2 in subsequent biophysical assays. ?-Helicity was confirmed by a crystal structure of the MDM2-peptide complex. This work introduces in?situ stapling as a versatile biocompatible technique with many other potential high-throughput biological applications.

SUBMITTER: Lau YH 

PROVIDER: S-EPMC5868729 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature