Protein (19)F NMR in Escherichia coli.

Although overexpression and (15)N enrichment facilitate the observation of resonances from disordered proteins in Escherichia coli, (15)N enrichment alone is insufficient for detecting most globular proteins. Here, we explain this dichotomy and overcome the problem while extending the capability of in-cell NMR by using (19)F-labeled proteins. Resonances from small (approximately 10 kDa) globular proteins containing the amino acid analogue 3-fluoro-tyrosine can be observed in cells, but for larger proteins the (19)F resonances are broadened beyond detection.

19F NMR studies of alpha-synuclein conformation and fibrillation.

Fibrils of the intrinsically disordered protein alpha-synuclein are hallmarks of Parkinson's disease. The fluorescent dye thioflavin T is often used to characterize fibrillation, but this assay may not provide quantitative information about structure and mechanism. To gain such information, we incorporated the 19F-labeled amino acid, 3-fluorotyrosine, into recombinant human alpha-synuclein at its endogenous tyrosine residues.

Alpha-Synuclein conformation affects its tyrosine-dependent oxidative aggregation.

Oxidative stress and aggregation of the protein alpha-synuclein are thought to be key factors in Parkinson's disease. Previous work shows that cytochrome c with H(2)O(2) causes tyrosine-dependent in vitro peroxidative aggregation of proteins, including alpha-synuclein. Here, we examine the role of each of alpha-synuclein's four tyrosine residues and how the protein's conformation affects covalent oxidative aggregation.