ISSN:
0947-6539
Keywords:
bilayers
;
cholesterol
;
membrane
;
probes
;
phospholipids
;
photolabelling
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
2H NMR, DSC and UV studies of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) vesicles have demonstrated the favourable physicochemical properties of the transmembrane phospholipid probes 1 a and 1 b for membrane topographical studies. In particular, in the presence of a physiological amount of cholesterol, only one transmembrane conformation is observed. The use of 1 a and cholesterol together for photolabelling experiments in DMPC vesicles led to a remarkable improvement in the regioselectivity of cross-linking between 1 a and DMPC, and between 1 a and cholesterol: the myristoyl chains functionalized at C11, C12 and C13 made up 95% of the total photolabelled myristates, and cholesterol was principally functionalized at the C25 position on the side-chain. This indicates the formation of a highly ordered bilayer structure and proves directly the orientation of cholesterol perpendicular to the membrane plane with its chain terminal buried in the middle of the bilayer.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/chem.19960020204
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