Native chemical ligation is a widely used technique for peptide fragment condensation in aqueous solutions, which has broken through the length limitation of traditional solid-phase peptide synthesis. It can achieve high-efficient chemical synthesis of proteins containing more than 300 amino acid residues. Peptide hydrazide, as a valuable reagent equivalent to a thioester peptide, can be easily and efficiently prepared by the Fmoc-based SPPS method and has been widely used in native chemical ligation. Here we take the chemical synthesis of a SARS-CoV-2 miniprotein inhibitor LCB1 as an example to describe the detailed procedure of hydrazide-based native chemical ligation.
COVID-19 , SARS-CoV-2 , Humans , Hydrazines , Peptides/chemistry , Solid-Phase Synthesis Techniques
We present the finding of a dimeric ACE2 peptide mimetic designed through side chain cross-linking and covalent dimerization. It has a binding affinity of 16 nM for the SARS-CoV-2 spike RBD, and effectively inhibits the SARS-CoV-2 pseudovirus in Huh7-hACE2 cells with an IC50 of 190 nM and neutralizes the authentic SARS-CoV-2 in Caco2 cells with an IC50 of 2.4 µM. Our study should provide a new insight for the optimization of peptide-based anti-SARS-CoV-2 inhibitors.
Antiviral Agents/pharmacology , Peptide Fragments/pharmacology , Peptidomimetics/pharmacology , SARS-CoV-2/drug effects , Amino Acid Sequence , Angiotensin-Converting Enzyme 2/chemistry , Antiviral Agents/chemical synthesis , Antiviral Agents/metabolism , Cell Line, Tumor , Humans , Microbial Sensitivity Tests , Peptide Fragments/chemical synthesis , Peptide Fragments/metabolism , Peptidomimetics/chemical synthesis , Peptidomimetics/metabolism , Protein Binding , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
We report a new pattern of a bicyclic helical peptide constructed through head-to-tail cross-linking. The described bicyclic helical peptide has a head-to-tail cross-linking arm and a C-terminal i, i + 4 cross-linking arm. This scaffold will provide a promising scaffold for designing a proteolytically resistant helix-constrained peptide.
Peptides