We investigated the effect of phosphatidylethanol (PEt) on fluidity and membrane tolerance to the fluidization induced by ethanol as well as on the activity of two membrane-bound enzymes, Na+/K+ ATPase and 5'-nucleotidase. PEt was synthesized from 1,2-dimyristoylphosphatidylcholine and phosphatidylcholine from bovine brain and studies were performed to determine the optimal experimental conditions for the insertion of PEt in natural bilayers. The effects of PEt, evaluated by differential scanning calorimetry or fluorescence polarization techniques, were studied in model membranes made of synthetic phospholipids or made of total lipids extracted from rat brain crude mitochondrial fraction (P2 fraction) and from natural membranes (P2 fraction). The presence of PEt increased the fluidity of artificial as well of natural membranes, but tolerance to the addition of ethanol, displayed by dimyristoylphosphatidylcholine vesicles and by natural membranes containing PEt, was lacking in vesicles made of dimyristoylphosphatidylethanolamine and in artificial bilayers reconstituted from total P2 lipid extracts, suggesting an involvement of PC on PEt-induced ethanol resistance. Na+/K+ ATPase activity was enhanced by the addition of small amounts of ethanol (up to 50 mM) and progressively inhibited at higher concentrations, while 5'-nucleotidase was not affected up to 400 mM ethanol. The presence of PEt in the bilayer exerted the opposite effects on the two enzymes, reducing the Na+/K+ ATPase activation induced by ethanol and enhancing 5'-nucleotidase activity. The mechanisms of the PEt-induced modifications are discussed.

Omodeo Salé, F., Lindi, C., Palestini, P., & Masserini, M. (1991). Role of phosphatidylethanol in membranes. Effects on membrane fluidity, tolerance to ethanol, and activity of membrane-bound enzymes. BIOCHEMISTRY, 30(9), 2477-2482.

Role of phosphatidylethanol in membranes. Effects on membrane fluidity, tolerance to ethanol, and activity of membrane-bound enzymes

PALESTINI, PAOLA NOVERINA ADA;MASSERINI, MASSIMO ERNESTO
1991

Abstract

We investigated the effect of phosphatidylethanol (PEt) on fluidity and membrane tolerance to the fluidization induced by ethanol as well as on the activity of two membrane-bound enzymes, Na+/K+ ATPase and 5'-nucleotidase. PEt was synthesized from 1,2-dimyristoylphosphatidylcholine and phosphatidylcholine from bovine brain and studies were performed to determine the optimal experimental conditions for the insertion of PEt in natural bilayers. The effects of PEt, evaluated by differential scanning calorimetry or fluorescence polarization techniques, were studied in model membranes made of synthetic phospholipids or made of total lipids extracted from rat brain crude mitochondrial fraction (P2 fraction) and from natural membranes (P2 fraction). The presence of PEt increased the fluidity of artificial as well of natural membranes, but tolerance to the addition of ethanol, displayed by dimyristoylphosphatidylcholine vesicles and by natural membranes containing PEt, was lacking in vesicles made of dimyristoylphosphatidylethanolamine and in artificial bilayers reconstituted from total P2 lipid extracts, suggesting an involvement of PC on PEt-induced ethanol resistance. Na+/K+ ATPase activity was enhanced by the addition of small amounts of ethanol (up to 50 mM) and progressively inhibited at higher concentrations, while 5'-nucleotidase was not affected up to 400 mM ethanol. The presence of PEt in the bilayer exerted the opposite effects on the two enzymes, reducing the Na+/K+ ATPase activation induced by ethanol and enhancing 5'-nucleotidase activity. The mechanisms of the PEt-induced modifications are discussed.
Articolo in rivista - Articolo scientifico
Calorimetry, Differential Scanning; Male; Submitochondrial Particles; Rats; Dimyristoylphosphatidylcholine; Liposomes; Animals; Ethanol; Intracellular Membranes; Kinetics; 5'-Nucleotidase; Membrane Fluidity; Sodium-Potassium-Exchanging ATPase; Rats, Inbred Strains; Spectrometry, Fluorescence; Membrane Lipids; Phosphatidylethanolamines; Brain
English
2477
2482
Omodeo Salé, F., Lindi, C., Palestini, P., & Masserini, M. (1991). Role of phosphatidylethanol in membranes. Effects on membrane fluidity, tolerance to ethanol, and activity of membrane-bound enzymes. BIOCHEMISTRY, 30(9), 2477-2482.
Omodeo Salé, F; Lindi, C; Palestini, P; Masserini, M
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/21454
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