β-sheet formation in BPTI(16–36) by Monte Carlo simulated annealing

Performing Monte Carlo simulated annealing simulations of a peptide fragment BPTI(16–36) from randomly chosen initial conformations, we have obtained a β-sheet structure as the lowest-energy conformation. The solvent effects were included by the term that is proportional to the solvent-accessible surface area. This lowest-energy structure has a type II′ β-turn and three characteristic intrachain hydrogen bonds that connect the two β-strands. It turns out that the positions of the reverse turn and hydrogen bonds are in remarkable agreement with the implications of an NMR experiment of the same fragment.