Molecular Dynamics Simulation of Structures of Two Homologous Surfactin Micelles

摘要

Micelles of n-C15 and iso-C16 surfactins in water at 298 K were studied by molecular dynamics simulation. The overall size and shape, the solvent accessible surface area and the radial density distribution of the micelles were investigated. The results indicate that micelle n-C15 is similar with micelle iso-C16 in the shape and solvent accessible surface except in the radial density distribution of the inside structure. Both of the micelles are mostly prolate ellipsoids in shape according to the principal moments of inertia, and the radii of surfactin micelles are found to be around 2.5 nm. The solvent accessible areas per surfactin molecule of micelle H-C15 and micelle iso-C16 were 3.87±0.07 and 3.85±0.05, respectively, and the peptide rings occupied most of the surface of both micelles. A few water molecules were found in the region between the hydrophobic core part and the peptide rings in micelles.