We have performed Molecular Dynamics simulations of ectoine, hydroxyectoine and urea in explicit solvent. Special attention has been spent on the characteristics of the local ordering of water molecules around these compatible solutes . Our results indicate that ectoine and hydroxyectoine are able to bind more water molecules than urea on short scales. Furthermore we investigated the number and appearance of hydrogen bonds between the molecules and the solvent. The simulations show that some specific groups in the compatible solutes are able to form a pronounced ordering of the local water structure. Additionally, we have validated that the charging of the molecules is of main importance . Furthermore we show the impact of a locally varying salt concentration . Experimental results are shown which indicate a direct influence of compatible solutes on the liquid expanded-liquid condensed phase transition in DPPC monolayers. We are able to identify a variation of the local water pressure around the comaptible solutes by numerical calculations as a possible reason for an experimentally observed broadening of the phase transition .
We have performed Molecular Dynamics simulations of ectoine, hydroxyectoine and urea in explicit solvent. Special attention has been spent on the local surrounding structure of water molecules . Our results indicate that ectoine and hydroxyectoine are able to accumulate more water molecules than urea by a pronounced ordering due to hydrogen bonds. We have validated that the charging of the molecules is of main importance resulting in a well defined hydration sphere. The influence of a varying salt concentration is also investigated. Finally we present experimental results of a DPPC monolayer phase transition that validate our numerical findings .
R
characteristics of the local ordering
local surrounding structure
D
around these compatible solutes
R
bind
accumulate
R
on short scales. Furthermore we investigated the number and appearance of hydrogen bonds between the molecules and the solvent. The simulations show that some specific groups in the compatible solutes are able to form
by
R
of the local water structure. Additionally, we
due to hydrogen bonds. We
R
. Furthermore we show the impact of a locally
resulting in a well defined hydration sphere. The influence of a
R
. Experimental results are shown which indicate a direct influence of compatible solutes on the liquid expanded-liquid condensed phase transition in DPPC monolayers. We are able to identify a variation of the local water pressure around the comaptible solutes by numerical calculations as a possible reason for an experimentally observed broadening of the phase transition
is also investigated. Finally we present experimental results of a DPPC monolayer phase transition that validate our numerical findings