Collect. Czech. Chem. Commun. 2011, 76, 695-711
Published online 2011-05-04 06:17:29

Interactions of molecular ions with model phospholipid membranes

Michal Petrova, Lukasz Cwiklika,b and Pavel Jungwirtha,*

a Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., and Center for Complex Molecular Systems and Biomolecules, 16610 Prague 6, Czech Republic
b J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i., 182 23 Prague 8, Czech Republic


The affinities of a series of biologically relevant ions for a hydrated phospholipid membrane were investigated using molecular dynamics simulation. Interactions of molecular ions, such as guanidinium, tetramethylammonium, and thiocyanate with the bilayer were computationally characterized for the first time. Simulations reveal strong ion specificity. On one hand, ions like guanidinium and thiocyanate adsorb relatively strongly to the headgroup region of the membrane. On the other hand, potassium or chloride interact very weakly with the phospholipids and merely act as neutralizing counterions. Calculations also show that these ions affect differently biophysical properties of the membrane, such as lipid diffusion, headgroup hydration and tilt angle.

Keywords: Biophysics; Molecular dynamics; Phospholipids.

References: 28 live references.