Monte carlo study on the system of aqueous amino acid solution

Abstract

Monte Carlo computer simulation on the system of aqueous solution with several amino acids such as $Ala^\pm$, $Ser^\pm$ and $Asp^\pm$ are carried out. Each system is composed of a cluster of 125 waters and an amino acid zwitter ion at 298 K. Detailed simulation conditions make good use of a standard metropolis algorithm under canonical ensemble(N.V.T). We try to put an amino acid in a previously equilibrated ensemble of water molecules and then analyze the energy distribution, radial distribution functions and four, five six and seven membered ring structures connected by hydrogen bond of water surrounding each amino acid. The six-membered ring is predominant in polar amino acid solution, whereas the five-membered ring in apolar amino acid solution.