Figure 5:

(a) 14 peptides were synthesized spanning Tpm sequence for either shrimp or pig proteins. Epitopes in red are prior to the initial pepsin cleavage site at residue 123 and defined as part of the N terminal half (NTH) of Tpm, conversely, epitopes downstream of the cleavage site are in the digestion-resistant (see Fig 2) C terminal half (CTH). (b – e) CD spectra of designed peptides from pig and shrimp Tpm sequences under neutral and acidic conditions. Spectra of peptides with overlap to epitopes within the NTH and CTH were colored red and blue respectively. Residue 123 in shrimp Tpm is suggested to be near the initial cleavage site for shrimp Tpm, peptide S7 overlaps it and is highlighted in yellow.