α-synuclein structures probed by 5-fluorotryptophan fluorescence and 19F NMR spectroscopy

被引：25

作者：

Winkler, GR ^{[1
]}

Harkins, SB ^{[1
]}

Lee, JC ^{[1
]}

Gray, HB ^{[1
]}

机构：

[1] CALTECH, Beckman Inst, Pasadena, CA 91125 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2006年 / 110卷 / 13期

关键词：

D O I：

10.1021/jp060043n

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

alpha-Synuclein, the main protein component of fibrillar deposits found in Parkinson's disease, is intrinsically disordered in vitro. Site-specific information on the protein conformation has been obtained by biosynthetic incorporation of an unnatural amino acid, 5-fluorotryptophan (5FW), into the recombinant protein. Using fluorescence and F-19 NMR spectroscopy, we have characterized three proteins with 5FW at positions 4, 39, and 94. Steady-state emission spectra (maxima at 353 nm; quantum yields approximate to 0.2) indicate that all three indole side chains are exposed to the aqueous medium. Virtually identical single-exponential excited-state decays (tau approximate to 3.4 ns) were observed in all three cases. Single F-19 NMR resonances were measured for W4, W39, and W94 at -49.0 +/- 0.1 ppm. Our analysis of the spectroscopic data suggests that the protein conformations are very similar in the regions near the three sites.

引用

页码：7058 / 7061

页数：4

共 46 条

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