Abstract: β-hairpins are popular secondary structural elements in native protein and play important roles either in protein folds or functionalization. Here we describe the design and preliminary structural studies of two peptide sequences LTVd-PGLTV (n7) and LTVGDDTV(n5) synthesized by solid phase peptide synthetic strategy. The circular dichroism (CD)spectra of n5 show a negative minimum near 198 nm, random coil characteristics. On the contrary, the CD spectra of n7 show a minimum at about 218 nm and a maximum at about 196 nm, a typical β-hairpin characteristics, which have been concluded as the common contribution of a β-turn mixed with β-sheets. The results show that β-turn, sequence context and β-sheet forming tendency are determinant of β-hairpin formation and stability.

Key words: de novo protein design, β-hairpin, β-turn, β-sheet