Current projects

Oxidized phospholipid membranes

Oxidation of lipids in phospholipid membranes is connected with various pathological conditions including Alzheimer’s disease, atherosclerosis and inflammation. Therefore, we study how the oxidative stress conditions  influence biophysical properties of phospholipid membranes. We employ classical molecular dynamics simulations, and thus we are able to obtain a molecular-level picture of lipid membrane under oxidative stress.  To gain a wider understanding of the undergoing processes, we confront the computational results with experimental fluorescence spectroscopy measurement done by our co-workers. Our goal is to connect biophysical properties of oxidized membranes with their biochemical and physiological features.

We described membrane destruction and pore formation in massively oxidized bilayers (link). We also studied changes of membrane fluidity that result from the chain reversal of oxidized lipid molecules in moderately oxidized bilayers (link). We suggested that oxidation of lipids in cell membrane can solely be responsible for the loss of membrane asymmetry and thus be important for signalling cell apoptosis (link). We demonstrated and quantified how lipid oxidation enhances permeability of lipid bilayer for water (link). We showed that oxidation of lipids is crucial for lipid monolayers which, for instance, form a lung surfactant (link). We studied the behavior of small aldehydes which are generated during lipid oxidation and are known to interact with proteins in both cell membrane and extracellular space (link). Most of our findings are summarized in the recent review paper (link).

• L. Cwiklik, P. Jungwirth, Chemical Physics Letters 2010, 486, 99-103. (link)
• L. Beranova, L. Cwiklik, P. Jurkiewicz, M. Hof, P. Jungwirth, Langmuir 2010, 26, 6140-6144. (link)
• R. Volinsky, L. Cwiklik, P. Jurkiewicz, M. Hof, P. Jungwirth, P. Kinnunen, Biophysical Journal 2011, 101, 1376-1384. (link)
• M. Lis, A. Wizert, M. Przybylo, M. Langner, J. Swiatek, P. Jungwirth, L. Cwiklik,
  Physical Chemistry Chemical Physics 2011, 13, 17555-17563. (link)
• M. Khabiri, M. Roeselova, L. Cwiklik, Chemical Physics Letters 2012, 519-520, 93-99. (link)
• M. Vazdar, P. Jurkiewicz, M. Hof, P. Jungwirth, L. Cwiklik, Journal of Physical Chemistry B 2012, accepted (link)
• P. Jurkiewicz, A. Olzynska, L. Cwiklik, E. Conte, P. Jungwirth, F.M. Megli, M. Hof, BBA Biomembranes 2012, accepted (link)

Interactions of ions with phospholipid membrane-water interfaces

Ions are inherently present at interfaces between phospholipid membranes and the water phase in vivo. Some of ions strongly and specifically interact with lipid membranes. Other interact weakly and non-specifically. And some ions are repelled from the water-membrane interface. The presence of ions has to be concerned to properly describe membrane-water interfaces. In our studies we focus on differences between physiologically relevant ions, like sodium and potassium, in their interactions with lipid bilayers. In particular, we are trying to identify local interfacial effects responsible for the ions-membrane interactions.

We described interactions of several physiologically relevant molecular ions with membrane-water interfaces (link). We studied interactions of sodium, potassium, and cesium cations with anionic membranes (link) as well as interactions of anions with cataionic bilayers (link). We also looked at the influence of the presence of ions at interactions between toxin peptides and membrane channels (link).

• M. Petrov, L. Cwiklik, P. Jungwirth, Collection of Czechoslovak Chemical Communications 2011, 76, 695-711.  (link)
• P. Jurkiewicz, L. Cwiklik, A. Vojtiskova, P. Jungwirth, M. Hof, BBA Biomembranes 2012, 1818, 609-616. (link)
• S. Pokorna, P. Jurkiewicz, L. Cwiklik, M. Vazdar, M. Hof, Faraday Discussions 2012, accepted (link)
• M. Khabiri, A. Nikouee, L. Cwiklik, S. Grissmer, R. Ettrich, Journal of Physical Chemistry B 2011, 115, 11490-11500. (link)

Clathrate hydrates

Clathrate hydrates are practically relevant mainly as possible methane sources and as materials for storage of methane or carbon dioxide. We recently showed that H-bonding guest molecules exhibit particularly interesting behavior in clathrates – with possible practical consequences for migration of guests in clathrate structures. In these studies molecular dynamics simulations are combined with experimental FTIR spectrospic techniques.

I.A. Monreal, L. Cwiklik, B. Jagoda-Cwiklik, J.P. Devlin, J. Phys. Chem. Lett. (2010), 1, 290-294.

V. Buch, J. P. Devlin, I. A. Monreal, B. Jagoda-Cwiklik, N. Aytemiz-Uras, L. Cwiklik, Phys. Chem. Chem. Phys. (2009), 11, 10245-10265.