Abstract: A simplified systematic search method for peptide conformational analysis was established, which changes subsequent main chain dihedral angles two by two by an increment of 10 degrees and selects low energy conformations according to energy contour maps. The characteristics of the method is the computational speed. It was applied to the conformational analysis of two linear pentapeptides which can cyclize to give a same product. The lowest energy conformations of both peptides show a turn-like structure. The distance between N_1 atom and C_5 atom correlates well with the cyclization reaction yield.

Key words: Peptide conformational analysis, Systematic search, Peptide cyclization yield