Hen egg white lysozyme fibrillation: a deep-UV resonance Raman spectroscopic study

Amyloid fibrils are associated with numerous degenerative diseases. The molecular mechanism of the structural transformation of native protein to the highly ordered cross-beta structure, the key feature of amyloid fibrils, is under active investigation. Conventional biophysical methods have limited application in addressing the problem because: of the heterogeneous nature of the system, In this study; we demonstrated that deep, UV resonance Raman (DUVRR) Spectroscopy in combination with circular dichroism (CD) and intrinsic tryptophan fluorescence allowed for quantitative characterization of protein structural evolution. at all stages of hen egg white lysozyme fibrillation in vitro. DUVRR spectroscopy was found to lie complimentary to the fur,UV CD because it is (i) more sensitive to beta-sheet than to alpha-helix, and (ii) capable of characterizing quantitatively inhomogeneous and highly light-scattering samples, In addition, phenylalanine, a natural DUVRR spectroscopic biomarker of protein structural rearrangements, exhibited substantial changes in the Raman cross section of the 1000-cm(-1) band at various stages of fibrillation. (C) 2008 by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim