Figure 1: Sequence comparison. (a) The primary sequence of wild-type recombinant HCV core antigen presented in single letter code. It consists of three components: pelB leader (from aa 1 to aa 31 in border-box), HCV core fragment containing domain I (from aa 32 to aa 154, total 123 aa), and His tag (from aa 155 to aa 162, underlined). (b) Five mutants with higher antigenicities are aligned with wild-type antigen covering residues 68 to 137. Four high-frequency mutation points at W84, P95, P110, and V129 are in boldface. The mutations are marked with a shaded box. The characters H, E, and C stand for alpha helices, beta strands, and random coil, respectively.