A combined attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR)-atomic force microscopy (AFM) platform was used to visualize and characterize membranolytic protein- and peptide-membrane interactions, allowing spectroscopic details to be correlated with structural features. Modifications to a previous combined platform permitted IR results for physiologically-relevant protein or peptide concentrations as well as provided nanometer-resolution height data for AFM. This combination provides greater insight than individual techniques alone. The interactions of hemolytic sticholysin proteins on a model red blood cell membrane showed evidence of conformational changes associated with a membrane-induced organization. In addition, the examination of a de novo cationic antimicrobial peptide on a model bacterial membrane showed that the peptide adopted a helical structure upon interaction with the membrane, and also provided evidence of membrane disruption and peptide aggregation. These results demonstrate that ATR-FTIR-AFM can be a powerful tool for understanding protein- and peptide-membrane interactions.
| Identifer | oai:union.ndltd.org:TORONTO/oai:tspace.library.utoronto.ca:1807/30585 |
| Date | 07 December 2011 |
| Creators | Edwards, Michelle |
| Contributors | Yip, Christopher M. |
| Source Sets | University of Toronto |
| Language | en_ca |
| Detected Language | English |
| Type | Thesis |
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