In Vitro Selection of Macrocyclic d/l-Hybrid Peptides against Human EGFR

Abstract

d/l-Hybrid peptides are an attractive class of molecular modality because they are able to exhibit high proteolytic stability and unique structural diversity which cannot be accessed by those consisting of only proteinogenic l-amino acids. Despite such an expectation, it has not been possible to devise de novo d/l-hybrid peptides capable of disrupting the function of a protein target(s) due to the lack of an effective method that reliably constructs a highly diverse library and screens active species. Here we report for the first time construction of a library consisting of 1012 members of macrocyclic d/l-hybrid peptides containing five kinds of d-amino acids and performance of the RaPID selection against human EGFR as a showcase to uncover PPI (protein–protein interaction) inhibitors.

In Vitro Selection of Macrocyclic α/β3-Peptides against Human EGFR

“…We have also recently reported the RaPID selection against the same hEGFR target using a D/L-hybrid macrocyclic peptide library bearing five kinds of D-α-amino acids (DAA), yielding two potent peptides, 2D and 18D, containing 5 and 6 DAAS, respectively. 34 1). Such consecutive and alternate incorporation of β 3 AAs had been previously considered formidable, but the use of an engineered tRNA, tRNA Pro1E2 , paired with EF-P, has made it possible.…”

Peptide‐Based Inhibitors for SARS‐CoV‐2 and SARS‐CoV

“…Regions like the HR1 and HR2 components of Spike protein have also proven good targets due to their importance in the stabilizing the virus‐cell interaction, though this method requires robust peptide design to counteract the viral fusion mechanism. While holding significant progress, peptide therapeutics still suffer from key limitations associated with: stability (API and formulation [ 99 , 186 , 187 , 188 , 189 ] /in vitro and in vivo [ 190 , 191 , 192 , 193 , 194 ] ); susceptibility to proteases [ 190 , 195 , 196 , 197 , 198 , 199 , 200 ] potential immune (IgG) responses [ 120 , 201 , 202 , 203 ] cost at scale [ 204 , 205 , 206 , 207 ] pharmacokinetic bioavailability. [ 208 , 209 , 210 , 211 , 212 ] Notwithstanding, numerous strategies have been explored to overcome these challenges and others, including self‐assembling peptides from our group [ 213 , 214 , 215 , 216 , 217 , 218 , 219 , 220 ] and others.…”

Peptide/protein-based macrocycles: from biological synthesis to biomedical applications

“…Iterative rounds of affinity-based selection and gradual enrichment of the active species give rise to the desired peptide macrocycles for targeted proteins. Using this technology, they successfully identified a series of peptide macrocycle-based inhibitors to factor XIIa (an initiator of the contact system), [172][173][174] calcium and integrin-binding protein 1 (an intracellular protein implicated in the survival and proliferation of triple-negative breast cancer), 175 influenza viral envelope protein hemagglutinin, 176 and human epidermal growth factor receptor (EGFR), 177,178 which provide potent drug candidates in antithrombotics, pneumonia prevention, and cancer therapy. Through effective cyclization and incorporating noncanonical amino acids, such as b-amino acids, D-amino acids, and L-carboranylalanine, these peptide macrocycles showed not only high inhibitory activity but also protease resistance and/or good cell permeability.…”