title: Low concentrated hydroxyectoine solutions in presence of DPPC lipid bilayers: a computer simulation study.
abstract: The influence of hydroxyectoine on the properties of the aqueous solution in presence of DPPC lipid bilayers is studied via semi-isotropic constant pressure (NPT) Molecular Dynamics simulations. We investigate the solvent-co-solute behavior in terms of Kirkwood-Buff integrals as well as hydrogen bond life times for an increasing hydroxyectoine concentration up to 0.15mol/L. The observed preferential exclusion mechanism identifies hydroxyectoine as a kosmotropic osmolyte. Our findings with regard to the DPPC lipid bilayer indicate an increase of the surface pressure as well as the solvent accessible surface area in presence of higher hydroxyectoine concentrations. The results are in agreement to the outcome of recent experiments. With this study, we are able to validate the visibility of co-solute-solute-solvent effects for low and physiologically relevant osmolyte concentrations.
authors.affiliation: Institut für Physikalische Chemie, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany; Institut für Computerphysik, Universität Stuttgart, D-70569 Stuttgart, Germany. Electronic address: smiatek@icp.uni-stuttgart.de.
authors.forename: Jens
authors.initials: J
authors.lastname: Smiatek
authors.forename: Rakesh Kumar
authors.initials: RK
authors.lastname: Harishchandra
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Galla
authors.forename: Andreas
authors.initials: A
authors.lastname: Heuer
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D000599:Amino Acids, Diamino / Q000737:chemistry*; D006860:Hydrogen Bonding; D008051:Lipid Bilayers / Q000737:chemistry*; D008962:Models, Theoretical; D056004:Molecular Dynamics Simulation; D012996:Solutions / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D055672:Static Electricity; D014867:Water / Q000737:chemistry
chemical_list: D000599:Amino Acids, Diamino; D008051:Lipid Bilayers; D012996:Solutions; D012997:Solvents; C121557:hydroxyectoine; D014867:Water; D015060:1,2-Dipalmitoylphosphatidylcholine
keywords: Compatible solutes; DPPC lipid bilayers; Kosmotropes; Molecular Dynamics simulations; Osmolytes