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Protein amyloids develop an intrinsic fluorescence signature during aggregation.

ABSTRACT: We report observations of an intrinsic fluorescence in the visible range, which develops during the aggregation of a range of polypeptides, including the disease-related human peptides amyloid-?(1-40) and (1-42), lysozyme and tau. Characteristic fluorescence properties such as the emission lifetime and spectra were determined experimentally. This intrinsic fluorescence is independent of the presence of aromatic side-chain residues within the polypeptide structure. Rather, it appears to result from electronic levels that become available when the polypeptide chain folds into a cross-? sheet scaffold similar to what has been reported to take place in crystals. We use these findings to quantify protein aggregation in vitro by fluorescence imaging in a label-free manner.

SUBMITTER: Chan FT

PROVIDER: S-EPMC5360231 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Protein amyloids develop an intrinsic fluorescence signature during aggregation.

Chan Fiona T S FT Kaminski Schierle Gabriele S GS Kumita Janet R JR Bertoncini Carlos W CW Dobson Christopher M CM Kaminski Clemens F CF

The Analyst 20130218 7

We report observations of an intrinsic fluorescence in the visible range, which develops during the aggregation of a range of polypeptides, including the disease-related human peptides amyloid-β(1-40) and (1-42), lysozyme and tau. Characteristic fluorescence properties such as the emission lifetime and spectra were determined experimentally. This intrinsic fluorescence is independent of the presence of aromatic side-chain residues within the polypeptide structure. Rather, it appears to result fr ...[more]

PMID: 23420088

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