کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5407252 | 1506050 | 2008 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Polarity dependence of EPR parameters for TOAC and MTSSL spin labels: Correlation with DOXYL spin labels for membrane studies
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
TOAC (2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid) is a nitroxyl amino acid that can be incorporated in the backbone of peptides. DOXYL (4,4-dimethyl-oxazolidine-1-oxyl) is a nitroxyl ring that can be attached rigidly at specific C-atom positions in the acyl chains of phospholipids. Spin-labelled phosphatidylcholines of the DOXYL type have been used previously to establish the transmembrane polarity profile in biological lipid bilayers [D. Marsh, Polarity and permeation profiles in lipid membranes, Proc. Natl. Acad. Sci. USA 87 (2001) 7777-7782]. Here, we determine the polarity dependence of the isotropic 14N-hyperfine couplings, aoN, and g-values, go, in a wide range of protic and aprotic media, for a TOAC-containing dipeptide (Fmoc-TOAC-Aib-OMe) and for a DOXYL-containing fatty acid (12-DOXYL-stearic acid). The correlation between datasets for TOAC and DOXYL nitroxides in the various solvents is used to establish the polarity profile for isotropic hyperfine couplings of TOAC in a transmembrane peptide. This calibration can be used to determine the location of TOAC at selected residue positions in a transmembrane or surface-active peptide. A similar calibration procedure is also applied to aoN and go for the pyrroline methanethiosulphonate nitroxide (MTSSL) that is used in site-directed spin-labelling studies of membrane proteins.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetic Resonance - Volume 190, Issue 2, February 2008, Pages 211-221
Journal: Journal of Magnetic Resonance - Volume 190, Issue 2, February 2008, Pages 211-221
نویسندگان
Derek Marsh, Claudio Toniolo,