Structure of α-Synuclein Bound to Polystyrene Surfaces Probed by Experimental and Theoretical Sum Frequency...

Area of Science:

• Biophysics
• Neuroscience
• Materials Science

Background:

• Hydrophobic interfaces are common and influence protein interactions.
• Alpha-synuclein (α-Syn) misfolding into amyloid aggregates is central to neurodegenerative diseases.
• Hydrophobic surfaces can accelerate α-Syn aggregation.

Purpose of the Study:

• To investigate the interfacial structure of α-Syn on a polystyrene (PS) film.
• To understand how plastic surfaces may induce α-Syn conformational changes.
• To compare α-Syn's structure on PS with its structure at air-water interfaces.

Main Methods:

• Vibrational sum frequency generation (VSFS) spectroscopy.
• Theoretical spectral calculations.
• Comparative analysis of interfacial structures.

Main Results:

• The entire NAC region and most N-terminal residues of α-Syn contact the PS surface.
• C-terminal residues of α-Syn extend away from the PS interface into solution.
• Distinct interfacial structural motifs of α-Syn on PS were identified.

Conclusions:

• Polymeric surfaces like PS play a critical role in promoting α-Syn misfolding.
• Elucidating α-Syn's structure at hydrophobic interfaces offers insights into disease mechanisms.
• Findings aid in developing strategies to mitigate α-Syn-related neurodegeneration.