TY - JOUR

T1 - Membrane-Sugar Interactions Probed by Pulsed Electron Paramagnetic Resonance of Spin Labels

AU - Konov, Konstantin B.

AU - Leonov, Dmitry V.

AU - Isaev, Nikolay P.

AU - Fedotov, Kirill Yu

AU - Voronkova, Violeta K.

AU - Dzuba, Sergei A.

PY - 2015/8/13

Y1 - 2015/8/13

N2 - Sugars can stabilize biological systems under extreme desiccation and freezing conditions. Hypothetical molecular mechanisms suggest that the stabilization effect may be determined either by specific interactions of sugars with biological molecules or by the influence of sugars on the solvating shell of the biomolecule. To explore membrane-sugar interactions, we applied electron spin echo envelope modulation (ESEEM) spectroscopy, a pulsed version of electron paramagnetic resonance (EPR), to phospholipid bilayers with spin-labeled lipids added and solvated by aqueous deuterated sucrose and trehalose solutions. The phospholipids were 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). The spin-labeled lipids were 1,2-dipalmitoyl-sn-glycero-3-phospho(TEMPO)choline (T-PCSL), with spin-label TEMPO at the lipid polar headgroup. The deuterium ESEEM amplitude was calibrated using known concentrations of glassy deuterated sugar solvents. The data obtained indicated that the sugar concentration near the membrane surface obeyed a simple Langmuir model of monolayer adsorption, which assumes direct sugar-molecule bonding to the bilayer surface.

AB - Sugars can stabilize biological systems under extreme desiccation and freezing conditions. Hypothetical molecular mechanisms suggest that the stabilization effect may be determined either by specific interactions of sugars with biological molecules or by the influence of sugars on the solvating shell of the biomolecule. To explore membrane-sugar interactions, we applied electron spin echo envelope modulation (ESEEM) spectroscopy, a pulsed version of electron paramagnetic resonance (EPR), to phospholipid bilayers with spin-labeled lipids added and solvated by aqueous deuterated sucrose and trehalose solutions. The phospholipids were 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). The spin-labeled lipids were 1,2-dipalmitoyl-sn-glycero-3-phospho(TEMPO)choline (T-PCSL), with spin-label TEMPO at the lipid polar headgroup. The deuterium ESEEM amplitude was calibrated using known concentrations of glassy deuterated sugar solvents. The data obtained indicated that the sugar concentration near the membrane surface obeyed a simple Langmuir model of monolayer adsorption, which assumes direct sugar-molecule bonding to the bilayer surface.

UR - http://www.scopus.com/inward/record.url?scp=84939245868&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcb.5b06864

DO - 10.1021/acs.jpcb.5b06864

M3 - Article

AN - SCOPUS:84939245868

VL - 119

SP - 10261

EP - 10266

JO - Journal of Physical Chemistry B

JF - Journal of Physical Chemistry B

SN - 1520-6106

IS - 32

ER -