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Segmental 13 C-Labeling and Raman Microspectroscopy of ?-Synuclein Amyloid Formation.

ABSTRACT: Mapping conformational changes of ?-synuclein (?-syn) from soluble, unstructured monomers to ?-sheet- rich aggregates is crucial towards understanding amyloid formation. Raman microspectroscopy is now used to spatially resolve conformational heterogeneity of amyloid aggregates and monitor amyloid formation of segmentally 13 C-labeled ?-syn in real-time. As the 13 C-isotope shifts the amide-I stretching frequency to lower energy, the ligated construct, 13 C1-86 12 CS87C-140 -?-syn, exhibits two distinct bands allowing for simultaneous detection of secondary structural changes in N-terminal 1-86 and C-terminal 87-140 residues. The disordered-to-?-sheet conformational change is first observed for the N-terminal followed by the C-terminal region. Finally, Raman spectroscopic changes occurred prior to Thioflavin T fluorescence enhancement, indicating that the amide-I band is a superior probe of amyloid formation.

SUBMITTER: Flynn JD

PROVIDER: S-EPMC6688611 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Segmental 13 C-Labeling and Raman Microspectroscopy of α-Synuclein Amyloid Formation.

Flynn Jessica D JD Jiang Zhiping Z Lee Jennifer C JC

Angewandte Chemie (International ed. in English) 20181127 52

Mapping conformational changes of α-synuclein (α-syn) from soluble, unstructured monomers to β-sheet- rich aggregates is crucial towards understanding amyloid formation. Raman microspectroscopy is now used to spatially resolve conformational heterogeneity of amyloid aggregates and monitor amyloid formation of segmentally 13 C-labeled α-syn in real-time. As the 13 C-isotope shifts the amide-I stretching frequency to lower energy, the ligated construct, 13 C1- ...[more]

PMID: 30371967

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