Cross-Validation of Simulation and EPR Oximetry Approaches: Membrane Cholesterol Reduces Oxygen Flux
| Autor: | Sally C. Pias, Gary Angles, Kristina Bueche, Casey R. Smith |
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| Rok vydání: | 2016 |
| Předmět: |
0303 health sciences
Materials science Bilayer Phospholipid Analytical chemistry Oxygen transport Biophysics chemistry.chemical_element Permeation Oxygen law.invention 03 medical and health sciences chemistry.chemical_compound Molecular dynamics 0302 clinical medicine Membrane chemistry law lipids (amino acids peptides and proteins) Electron paramagnetic resonance 030217 neurology & neurosurgery 030304 developmental biology |
| Zdroj: | Biophysical Journal. 110(3) |
| ISSN: | 0006-3495 |
| DOI: | 10.1016/j.bpj.2015.11.2219 |
| Popis: | Prior EPR oximetry work by Subczynski and colleagues has shown that cholesterol increases membrane resistance to oxygen permeation by 3- to 5-fold when present in a 1:1 ratio with phospholipid. In the current study, we use molecular dynamics simulations to investigate the biophysics of oxygen transport in membranes incorporating cholesterol. The simulations enable cross-validation of the EPR oximetry measurements and the simulations. Further, we have been able to observe oxygen transport near the bilayer surface, which has not been accessible to EPR spin-label probes. We find excellent agreement between the simulation and EPR observations. Our simulations affirm that cholesterol reduces oxygen flux when present at a 1:1 ratio with phospholipid. They further indicate that the bilayer surface in the presence or absence of cholesterol presents greater resistance to permeation than previously observed by EPR. |
| Databáze: | OpenAIRE |
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