Molecular dynamics studies of membranes and membrane proteins

Properties of phospholipid membrane bilayers and of proteins associating and functioning in the membrane bilayer or at the membrane-water interface are studied by combining molecular dynamics simulations, free energy perturbation theory and continuum electrostatics calculations. Three systems were investigated: (1) The proton pump cycle of the integral membrane protein bacteriorhodopsin: The photoisomerization and subsequent thermal reactions of the protein were studied by molecular dynamics simulations. Internal water molecules were placed in the protein. The studies attribute a key role to the Schiff base-counterion electrostatic interaction in controlling the initial photoreaction and revealed an important role of internal water molecules for the function of bacteriorhodopsin. (2) A dilaurylphosphatidylethanolamine membrane bilayer solvated in excess water: Structural properties of the membrane, electrostatic properties of the membrane-water interface and charge distributions on the membrane surface were characterized. (3) The activation of enzyme human synovial phospholipase A$\sb2$ at membrane surface was investigated. The activation was attributed to desolvation effects of lipid head groups in a tight enzyme-membrane complex. The electrostatic interactions between the enzyme and the membrane were studied and found to favor the binding of negatively charged lipid molecules to the enzyme-membrane interface.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biophysics and Computational Biology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Zhou, Feng

Contributors dc:contributor

• Schulten, Klaus J.

• Biology, Molecular
• Chemistry, Biochemistry
• Chemistry, Physical

Statement dc:rights

• Copyright 1996 Zhou, Feng

Language dc:language

eng

Identifier

AAI9625221
(UMI)AAI9625221

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22296