Influence of protein and lipid domains on the structure, fluidity and phase behavior of lipid bilayer membranes

The lipid bilayer forms the basic structure of the cell membrane, which is a heterogeneous matrix of proteins and lipids that provides a barrier between the interior of a cell and its outside environment. Protein and lipid domains in cell membranes can facilitate receptor localization, stabilize membranes, and influence membrane fluidity. In this thesis, we study how ordered protein and lipid domains influence the physical properties of lipid bilayers to better understand the roles of membrane domains in biological mechanisms. Model cellular membranes that mimic the behavior of biological membranes offer a controllable environment for systematically studying the isolated effects of protein and lipid ordering on membrane organization. Using fluid and solid-supported lipid bilayers, we study ordered peripheral membrane proteins and lateral lipid phase separation with fluorescence microscopy and X-ray reflectivity. To model cellular protein coatings and peripheral proteins, we prepare biotin-functionalized membranes that bind the proteins streptavidin and avidin. Fluorescence microscopy studies demonstrate that proteins crystallized in a single layer on lipid bilayer surfaces can change the lipid curvature and stabilize lipid vesicles against osmotic collapse.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Horton, Margaret R. (Margaret Ruth)

Advisor dc:contributor.advisor

• Alice P. Gast.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/38982

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38982