The peptide Mono-M2e is composed of a pentameric coiled coil (green) and a trimeric coiled coil (blue). Tetra-M2e uses the same trimer but has a tetrameric coiled coil (turquoise). In both sequences, the M2e epitope is shown in red. Other amino acid residues, such as linkers and his-tags, are shown in black. M2eN-GCN4 consists of M2e attached to the tetrameric GCN4 coiled coil, shown in brown. Monomeric M2e, used for ELISA, coating is shown in red.