Popis: |
Amyloid proteins which can form cytotoxic structures are related to incurable illnesses. Despite a significant amount of continuous research, there is a lack of knowledge explaining the molecular mechanisms of neurodegenerative disorders. The polymorphic structure of the amyloid fibril, as well as the range of binding and supporting forces, challenge in situ examination of amyloid diseases. The ability to identify the secondary structures of amyloid proteins and observe their interactions with phospholipids on fluid interfaces is highly relevant for many scientific fields. In order to understand protein aggregation and the interaction of protein aggregates with cell membranes, it is beneficial, to begin with, a simplified biomimetic system, e.g., a monolayer formed from one kind of lipid and a protein. Vibrational sum-frequency generation spectroscopy (VSFG) combined with Langmuir technique fits perfectly in studying such systems. With the advancements in techniques of surface-specific spectroscopy, VSFG has distinctively large surface specificity and submonolayer sensitivity and is an ideal optical probe to identify the secondary structure of surface-adsorbed proteins. This dissertation focuses on the adsorption of hen egg white lysozyme (HEWL) and the secondary structures of its aggregates at various interfaces using the VSFG method. The widely used phospholipid deuteration method was applied in this study, furthermore, its impact on the biomimetic system was assessed. The dissertation includes a wide range of interdisciplinary methods, which revealed the main features of biomimetic systems and ensured the implementation of the main goal of this study. |