Stefl Martin, Sachl Radek, Olżyńska Agnieszka, Amaro Mariana, Savchenko Dariya, Deyneka Alexander, Hermetter Albin, Cwiklik Lukasz, Humpolíčková Jana, Hof Martin
J. Heyrovský Institute of Physical Chemistry of the Academy of Sciences of the Czech Republic, v. v. i., Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
Institute of Physics, Academy of Sciences of the Czech Republic, v. v. i., Na Slovance 1999/2, 182 21 Prague 8, Czech Republic.
Biochim Biophys Acta. 2014 Jul;1838(7):1769-76. doi: 10.1016/j.bbamem.2014.02.006. Epub 2014 Feb 22.
Biological membranes are under significant oxidative stress caused by reactive oxygen species mostly originating during cellular respiration. Double bonds of the unsaturated lipids are most prone to oxidation, which might lead to shortening of the oxidized chain and inserting of terminal either aldehyde or carboxylic group. Structural rearrangement of oxidized lipids, addressed already, is mainly associated with looping back of the hydrophilic terminal group. This contribution utilizing dual-focus fluorescence correlation spectroscopy and electron paramagnetic resonance as well as atomistic molecular dynamics simulations focuses on the overall changes of the membrane structural and dynamical properties once it becomes oxidized. Particularly, attention is paid to cholesterol rearrangement in the oxidized membrane revealing its preferable interaction with carbonyls of the oxidized chains. In this view cholesterol seems to have a tendency to repair, rather than condense, the bilayer.
生物膜承受着由主要源自细胞呼吸过程中的活性氧物种所引起的显著氧化应激。不饱和脂质的双键最容易被氧化，这可能导致氧化链缩短，并在末端插入醛基或羧基。如前所述，氧化脂质的结构重排主要与亲水性末端基团的回折有关。本研究利用双焦点荧光相关光谱、电子顺磁共振以及原子分子动力学模拟，聚焦于膜被氧化后其结构和动力学性质的整体变化。特别地，关注了氧化膜中胆固醇的重排，揭示了其与氧化链羰基的优先相互作用。从这个角度来看，胆固醇似乎倾向于修复而非凝聚双层膜。
