Indeed, circular dichroism (CD) studies of selected peptides associated with biological activities (Tables 1 and 2) indicate that they predominantly assume an a-helical conformation in water. Peptides 14, 27 and 45 ( Figure S1A ) exhibit a CD pattern characteristic of a high a-helical content, whereas the remaining peptides show CD profiles similar to that shown for peptide 12 ( Figure S1B ) or intermediate between those shown in Figures S1A and S1B characteristic of a partial a-helical organization. When analyzed by size exclusion chromatography on FPLC columns, peptides presented elution profiles between those exhibited by chymotrypsin and ribonuclease (MW 24 and 13kDa, respectively). The CD and size exclusion chromatography results suggest that peptides adopt an a-helical coiled-coil structure, which need to be unambiguously ascertained by NMR and ultra-centrifugation studies.