Molecular dynamics study on the stabilization of dehydrated lipid bilayers with glucose and trehalose

In this study, we use molecular dynamics simulations to investigate and compare the interactions of DPPC bilayers with and without saccharides (glucose or trehalose) under dehydrated conditions. Results from the simulations indicate that unilamellar bilayers lose their structural integrity under dehydrated conditions in the absence of saccharides; however, in the presence of either glucose or trehalose, the bilayers maintain their stability. Hydrogen bond analysis shows that the saccharide molecules displace a significant amount of water surrounding the lipid headgroups. At the same time, the additional hydrogen bonds formed between water and saccharide molecules help to maintain a hydration layer on the lipid bilayer interface. On the basis of the hydrogen bond distributions, trehalose forms more hydrogen bonds with the lipids than glucose, and it is less likely to interact with neighboring saccharide molecules. These results suggest that the interaction between the saccharide and lipid molecules through hydrogen bonds is an essential component of the mechanism for the stabilization of lipid bilayers.