Thioester Bond Liability: Study on Natural Influenza and Model Acylpeptides

Introduction Influenza A hemagglutinin ( ) is a major envelope glycoprotein having attachment and fusion functions to deliver viral nucleoprotein into the host cell. It is a spike homotrimer; each monomer consists of two disulfide-linked chains (HA1 and HA2) and is anchored in the membrane by the light HA2 chain C-terminal segment. Three conservative cysteine residues of the segment were shown to be palmitoylated via thioester bond [1] (Fig.1). Probably, fatty acids may serve to orient the TMD in the lipid bilayer and influence membrane fusion processes.