biostudies-literatureUnknown19(2)Worch RCleavage of hemagglutinin precursor (HA0) by cellular proteases results in the formation of two subunits, HA1 and HA2. The N-terminal fragment of HA2, named a fusion peptide (HAfp), possess a charged, amine N-terminus. It has been shown that the N-terminus of HAfp stabilizes the structure of a helical hairpin observed for a 23-amino acid long peptide (HAfp1-23), whose larger activity than HAfp1-20 has been demonstrated recently. In this paper, we analyze the effect of N-terminal charge on peptide-mediated fusion efficiency and conformation changes at the membrane interface by comparison with the corresponding N-acetylated peptides of 20- and 23-amino acid lengths. We found that higher fusogenic activities of peptides with unmodified amino termini correlates with their ability to form helicInternational journal of molecular sciencesE578https://www.ebi.ac.uk/biostudies/studies/S-EPMC5855800biostudies-literatureCharged N-terminus of Influenza Fusion Peptide Facilitates Membrane Fusion.PMC5855800Dudek ASzymaniec ASetny PKrupa JWorch RfalseCharged N-terminus of Influenza Fusion Peptide Facilitates Membrane Fusion.Cleavage of hemagglutinin precursor (HA0) by cellular proteases results in the formation of two subunits, HA1 and HA2. The N-terminal fragment of HA2, named a fusion peptide (HAfp), possess a charged, amine N-terminus. It has been shown that the N-terminus of HAfp stabilizes the structure of a helical hairpin observed for a 23-amino acid long peptide (HAfp1-23), whose larger activity than HAfp1-20 has been demonstrated recently. In this paper, we analyze the effect of N-terminal charge on peptide-mediated fusion efficiency and conformation changes at the membrane interface by comparison with the corresponding N-acetylated peptides of 20- and 23-amino acid lengths. We found that higher fusogenic activities of peptides with unmodified amino termini correlates with their ability to form helic2018-01-01T00:00:00Z2018 Feb2025-04-26T22:12:59.537Z2019-03-26T23:23:11ZS-EPMC58558002944394510.3390/ijms19020578