SARS-CoV-2-derived fusion inhibitor lipopeptides exhibit highly potent and broad-spectrum activity against divergent human coronaviruses

摘要

Design and characterization of potent and broad-spectrum fusion inhibitors against divergent human coronaviruses. a Schematic diagram of functional domains of the S protein. SP signal peptide, FP fusion peptide, HR1 heptad repeat 1, HR2 heptad repeat 2, TM transmembrane domain, CT cytoplasmic tail. The S1/S2 and S2’ cleavage sites are marked with arrows. The HR1 and HR2 core sequences of representative HCoVs are listed, and the potential residues mediating the HR1–HR2 interactions within the 6-HB core structure are colored in red. b HCoV HR2-derived fusion inhibitor peptides and lipopeptides. The residues marked in blue indicate the amino acid changes relative to the template sequence in IPB02. The residues in green indicate the amino acid changes relative to the template sequence in OC43-LP. Chol cholesterol, PEG8 8-unit polyethylene glycol, PEG4 4-unit polyethylene glycol, GSGSG a flexible amino acid linker. c–f Secondary structure and binding stability of IPB02-based fusion inhibitor lipopeptides. The α-helicity and thermostability of lipopeptides alone (c, d) or in complexes with the SARS-CoV-2 HR1 target mimic peptide HR1P (e, f) were determined by CD spectroscopy, with the final concentration of each lipopeptide being 10 μM. The experiments were performed two times, and representative data are shown. g The inhibitory activity of various fusion inhibitors against SARS-CoV-2 and other human CoVs. Both dual-split-protein (DSP)-based cell–cell fusion assay and pseudovirus (PV)-based single infection assay were repeated three times, and data are expressed as the means ± standard deviations (SD). D614G represents the SARS-CoV-2 S protein-bearing D614G mutation