Biomaterial Database

A new paramagnetic analogue of cholesterol as a tool for studying molecular interactions of genuine cholesterol. 1987

L Maurin, and P Morin, and A Bienvenue

The synthesis of a new paramagnetic (nitroxide) analogue of cholesterol is described. This compound (called CNO) contains a doxyl group in the lateral chain at position 25. Our results show that CNO retains three molecular interactions which characterize authentic cholesterol: It assumes an orientation perpendicular to the phospholipid bilayer with the doxyl group buried in the membrane core, as seen by ESR spectroscopy. It widens the transition temperature of dimyristoylphosphatidylcholine, to the same extent as cholesterol, as measured by Raman and ESR spectroscopies. It interacts with polyene antibiotics, such as amphotericin B and filipin, in the same manner as its model. This was proved on the one hand by the change in fluorescence of self quenched vesicle-entrapped calcein, after dilution in the external medium, provoked by filipin, and on the other hand by fluorescence quenching provoked by cobalt ions entering the vesicles under the influence of amphotericin B. We concluded that CNO, although it has a side chain different from genuine cholesterol, can help to solve many physiologically meaningful questions related to the distribution and movement rate of cholesterol itself.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D008968	Molecular Conformation	The characteristic three-dimensional shape of a molecule.	Molecular Configuration,3D Molecular Structure,Configuration, Molecular,Molecular Structure, Three Dimensional,Three Dimensional Molecular Structure,3D Molecular Structures,Configurations, Molecular,Conformation, Molecular,Conformations, Molecular,Molecular Configurations,Molecular Conformations,Molecular Structure, 3D,Molecular Structures, 3D,Structure, 3D Molecular,Structures, 3D Molecular
D010713	Phosphatidylcholines	Derivatives of PHOSPHATIDIC ACIDS in which the phosphoric acid is bound in ester linkage to a CHOLINE moiety.	Choline Phosphoglycerides,Choline Glycerophospholipids,Phosphatidyl Choline,Phosphatidyl Cholines,Phosphatidylcholine,Choline, Phosphatidyl,Cholines, Phosphatidyl,Glycerophospholipids, Choline,Phosphoglycerides, Choline
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D004578	Electron Spin Resonance Spectroscopy	A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.	ENDOR,Electron Nuclear Double Resonance,Electron Paramagnetic Resonance,Paramagnetic Resonance,Electron Spin Resonance,Paramagnetic Resonance, Electron,Resonance, Electron Paramagnetic,Resonance, Electron Spin,Resonance, Paramagnetic
D005372	Filipin	A complex of polyene antibiotics obtained from Streptomyces filipinensis. Filipin III alters membrane function by interfering with membrane sterols, inhibits mitochondrial respiration, and is proposed as an antifungal agent. Filipins I, II, and IV are less important.	Filipin III,Desoxylagosin,Filimarisin,Filipin I,Filipin II,Filipin IV,NSC-3364,U-5956,NSC 3364,NSC3364,U 5956,U5956
D000666	Amphotericin B	Macrolide antifungal antibiotic produced by Streptomyces nodosus obtained from soil of the Orinoco river region of Venezuela.	Amphocil,Amphotericin,Amphotericin B Cholesterol Dispersion,Amphotericin B Colloidal Dispersion,Fungizone
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence