Degree Type

Thesis

Date of Award

1-1-2003

Degree Name

Master of Science

Department

Materials Science and Engineering

Major

Materials Science and Engineering

Abstract

"The major goal of this research is to understand design principles of interfaces, suitable for the reconstitution the ion channel membrane proteins. In the present work, we focused on the immobilization of two channel proteins, α-Hemolysin from Staphylococcus aureus and Mechanosensitive Ion Channel of Large Conductance (MscL) from Salmonella typhimurium, onto single crystal silicon substrates (silicon wafers). High-resolution atomic force microscopy (AFM) was utilized as a tool for the monitoring of the molecular conformations of the ion channels after immobilization. As observed, α-Hemolysin was adsorbed onto bare silicon in collapsed state, while adsorption of MscL resulted in unraveling of the protein. LB deposition of proteins embedded in lipid monolayer reduced denaturation of the proteins on silicon surface, due to reduced surface energy. Octadecyltimethoxy silane (ODTMS) self-assembled monolayers (SAMs) were used as a ""buffer layer analog"" of a lipid membrane. MscL was successfully reconstituted in these organic SAMs. Analysis of dimensions of the MscL displayed that the gating state and the molecular conformation of SAM-supported MscL can be controlled by variation of the surface energy of the supporting surface layer. Closed, intermediate, and open states were observed on surfaces with different surface tensions. Obtained results demonstrated an agreement with known molecular modeling data for gating mechanisms of the MscL protein in lipid membrane."

DOI

https://doi.org/10.31274/rtd-20200716-99

Copyright Owner

Maryna Ornatska

Language

en

OCLC Number

52698582

File Format

application/pdf

File Size

82 pages

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