University of Illinois Urbana-Champaign

Structure, conformational dynamics and formation of large amyloids: the case of alpha-synuclein fibrils

Comellas Canal, Gemma

Content Files
ComellasCanal_Gemma.pdf

Permalink

https://hdl.handle.net/2142/31996

Description

Title
Structure, conformational dynamics and formation of large amyloids: the case of alpha-synuclein fibrils
Author(s)
Comellas Canal, Gemma
Issue Date
2012-06-27T21:23:42Z
Director of Research (if dissertation) or Advisor (if thesis)
Rienstra, Chad M.
Doctoral Committee Chair(s)
Rienstra, Chad M.
Committee Member(s)
  • George, Julia M.
  • Schulten, Klaus J.
  • Martin, Gruebele H.
Department of Study
School of Molecular & Cell Bio
Discipline
Biophysics & Computnl Biology
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Date of Ingest
2012-06-27T21:23:42Z
Keyword(s)
  • Nuclear magnetic resonance (NMR)
  • magic-angle spinning (MAS)
  • protein structure
  • alpha-synuclein (AS)
Abstract
In my thesis, I have focused on new methodology development combined with state-of-the-art solid-state nuclear magnetic resonance (NMR) experiments with scanning transmission electron microscopy (STEM) to obtain atomic level structural information of the alpha-synuclein (AS) fibrils and the mechanism of their formation; We first investigated the effect of protein deuteration and 1H decoupling optimization to maximize the resolution and sensitivity of biomolecular solid-state NMR; We then applied state-of-the-art solid-state NMR experiments to do a detailed structural characterization and conformational dynamics of AS fibrils using improved sample preparation and labeling schemes; These results show that the core of the fibrils extends for about 70 residues with a repeated secondary structure motif; Additionally, it demonstrates that the three mutation sites (A30P, E46K, A53T) are located in structured regions of the fibrils; Upon mutation, we have shown that the structure suffers major and minor perturbations by E46K and A53T, respectively; while the structure is unaltered by A30P; The fibril formation has also been investigated by capturing the transition from α-helical to β-sheet at the atomic level using solid-state NMR; Additionally, to investigate the AS fold, the mass-per-length (MPL) measurement of the fibrils has been obtained using STEM that together with solid-state NMR restraints have been used to propose possible models of how the fibrils arrange; Finally, initial results for solving 3D high-resolution structures of large proteins with new computational methods have been investigated.
Graduation Semester
2012-05
Permalink
http://hdl.handle.net/2142/31996
Copyright and License Information
Copyright 2012 Gemma Comellas Canal

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