کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7692110 | 1496264 | 2018 | 26 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Ether-linked lipids: Spin-label EPR and spin echoes
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی (عمومی)
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Ether-linked lipids: Spin-label EPR and spin echoes Ether-linked lipids: Spin-label EPR and spin echoes](/preview/png/7692110.png)
چکیده انگلیسی
Electron spin echo envelope modulation (ESEEM) and conventional electron paramagnetic resonance (EPR) of site-specifically spin-labelled phospholipids are used to investigate the effect of ether-linked chains on the water-penetration and polarity profiles, as well as the phase behaviour and chain flexibility profiles, of phospholipid membranes. D2O-ESEEM reveals that water exposure of the terminal methyl groups in the interdigitated phase of dihexadecyl phosphatidylcholine (DHPC) is comparable to that of the methylene groups at the polar head-group end of the chains. Similarly, an uniform transmembrane polarity profile is obtained from the dependence of the outer 14N-hyperfine splitting on the spin-label position along the chain in frozen interdigitated DHPC dispersions. Two-component conventional EPR spectra of spin labels at the terminal methyl end of the chain reveal that the intermediate gel phase above the pretransition of DHPC contains components in which the lipid chains are interdigitated. The polarity and chain-flexibility profiles in the fluid Lα-phase of DHPC with ether-linked chains are shifted outwards, towards the polar-apolar interface, as compared with that of dihexadecanoyl phosphatidylcholine (DPPC) with ester-linked chains. Also, the polarity profile of DHPC is shifted upwards, to higher polarities. These differences reflect those in hydrocarbon thickness and area/lipid molecule reported by x-ray diffraction for the Lα-phases of the two lipids.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemistry and Physics of Lipids - Volume 212, May 2018, Pages 130-137
Journal: Chemistry and Physics of Lipids - Volume 212, May 2018, Pages 130-137
نویسندگان
Maria Oranges, Rita Guzzi, Derek Marsh, Rosa Bartucci,