The effects of solvent and temperature on the structural integrity of monomeric melittin by molecular dynamics simulations

In this study, the secondary structural integrity of monomeric melittin was shown to depend strongly on the solvent by 200 ps molecular dynamics simulations with temperature jump technique. The α-helix content of melittin increased with increasing the aliphatic chain length of alcohol and decreased with increasing simulation temperature. In addition, the melting temperature of melittin, at which the averaged helicity decreased to 50%, was linearly correlated to the aliphatic chain length of alcohol. The weaker dielectric constant of longer aliphatic chain length of alcohol possibly reduces the hydrogen bonding between amide protons and surrounding solvent molecules and simultaneously promotes the intramolecular hydrogen bonding in melittin and therefore stabilizes the secondary structure of melittin.