An 18-amino acid polypeptide systemin was synthesized by the solid-phase me
thod and its conformation was studied by circular dichroism spectroscopy. T
he peptide in solution is a mixture of random coil structure with beta-shee
t and beta-turn motifs as has been previously suggested with NMR spectra. F
ree zone capillary electrophoresis analysis proved purity and chemical stab
ility of systemin at different pH.