Dissertation
Studies of the molecular effects of a solid support upon lipid membranes and membrane bound proteins
Washington State University
Doctor of Philosophy (PhD), Washington State University
12/2009
DOI:
https://doi.org/10.7273/000005919
Abstract
Often, membrane / protein systems are studied and / or utilized on solid supports. The underlying substrate in solid supported lipid bilayer assemblies causes large perturbations to the membrane, but the nature of these effects are not well understood. To gain an understanding, these effects were studied on two fronts: the effect upon the membrane by itself, and then the effects upon a membrane / protein system. First, all-atom molecular dynamics (MD) simulations of DLPC, DMPC, POPC, and DEPC on a hydroxylated nanocrystalline [alpha]-quartz (011) slab revealed a pronounced thinning effect in the lipid bilayers. It was shown that this thinning effect proceeded by one of two mechanisms: the first through a curling of the terminal methyl groups at the interface of the opposing leaflets, and the second through increased interdigitation of the alkyl chains. Also, with the introduction of the solid support, marked asymmetries in a number of structural properties were reported. These asymmetries included (a) the surface area per lipid, (b) the electron densities of the polar head groups, (c) the radial distributions of the choline groups, and (d) the average orientation of water surrounding the membranes. Next, the free energy perturbation method was used to begin calculating the change in free energy ([delta]Gbinding) from a Gramicidin monomer to its dimeric state, which were simulated via MD of supported DLPC, DMPC, and DEPC bilayers. The most notable effect was an asymmetry of the calculated free energies relative to the bilayer side closest to the solid support. In all three systems, there was a large difference in free energy between the Gramicidin monomers that were close to the support and the monomers further from the support.
Metrics
4 File views/ downloads
15 Record Views
Details
- Title
- Studies of the molecular effects of a solid support upon lipid membranes and membrane bound proteins
- Creators
- Christopher M. Hartshorn
- Contributors
- James A. Brozik (Chair)Kerry W Hipps (Committee Member) - Washington State University, Department of ChemistryUrsula M Mazur (Committee Member) - Washington State University, Department of ChemistryKirk Arnold Peterson (Committee Member) - Washington State University, Department of ChemistryJames O. Schenck (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Department of Chemistry
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Publisher
- Washington State University
- Number of pages
- 284
- Identifiers
- 99901055130701842
- Language
- English
- Resource Type
- Dissertation