Effects of lysophosphatidylcholines on phosphatidylcholine and phosphatidylcholine/cholesterol liposome systems as revealed by 31P-NMR, electron microscopy and permeability studies

Echteld, C.J.A. van; Kruijff, Ben de; Mandersloot, J.G.; Gier, J. De

doi:10.1016/0005-2736(81)90408-9

Cited by 147 publications

(61 citation statements)

References 29 publications

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“…The small value of Aa found in these systems is in good agreement with those previously reported [12,13] for lysoPC in a variety of different bilayers and indicate an increased motional freedom of the lipid head group due to increased rotational possibilities around the glycerol C2-C3 bond [32,33]. From the spectra of the various samples the relative amount of 'bilayer signal' was obtained (Fig.…”

Section: Interaction Of Gramicidin Analogs and Lysopc Systemssupporting

confidence: 90%

Importance of the tryptophans of gramicidin for its lipid structure modulating activity in lysophosphatidylcholine and phosphatidylethanolamine model membranes. A comparative study employing gramicidin analogs and a synthetic α-helical hydrophobic polypeptide

Aranda

Killian

Kruijff

1987

Biochimica et Biophysica Acta (BBA) - Biomembranes

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The importance of the tryptophan residues of gramicidin for the lipid structure modulating activity of this pentadecapeptide was investigated by studying the interaction of gramicidin analogs A, B, C (which have a tryptophan, phenylalanine and tyrosine in position 11, respectively) and tryptophan-N-formylated gramicidin (in which the four tryptophan residues have been formylated) with several phospholipid systems. In addition an a-helical model pentadecapeptide (P15) was studied to further test the specificity of the gramicidin-lipid interaction. DSC experiments showed that all the gramicidin analogs produced a significant decrease in the gel to liquid-crystalline transition enthalpy of dipalmitoylphosphatidylcholine. The P15 peptide was much less effective in this respect. In dielaidoyiphosphatidylethanolamine the gel ~ liquid-crystalline transition enthalpy was much less affected by the incorporation of these molecules. In this lipid system tryptophan-Nformylated gramicidin was found to be the most ineffective. 31p-NMR and small angle X-ray diffraction experiments showed that the ability of the peptides to induce bilayer structures in paimitoyilysophosphatidyicholine and H n phase promotion in dielaidoylphosphatidylethanolamine systems follows the order. gramicidin A' (natural mixture) -~ gramicidin A > gramicidin B = gramicidin C > tryptophan-N-formylated gramicidin > P15. These results support the hypothesis that the shape of gramicidin and its aggregational behaviour, in which the tryptophan residues play an essential role, are major determinants in the unique lipid structure modulating activity of gramicidin.

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Section: Interaction Of Gramicidin Analogs and Lysopc Systemssupporting

confidence: 90%

Importance of the tryptophans of gramicidin for its lipid structure modulating activity in lysophosphatidylcholine and phosphatidylethanolamine model membranes. A comparative study employing gramicidin analogs and a synthetic α-helical hydrophobic polypeptide

Aranda

Killian

Kruijff

1987

Biochimica et Biophysica Acta (BBA) - Biomembranes

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“…and W. J. Baumann, unpublished observations). It was shown earlier that C16-, C18-, and C20-lysoPC form interdigitated bilayer structures at temperatures below their bilayermicellar transition temperature (11,34). However, the results presented in Fig.…”

Section: Resultscontrasting

confidence: 53%

“…A similar explanation can be given for ternary systems in which Chol (Fig. 5, triangles) (11,26,32). For the lysoPC system containing equimolar amounts of PC and Chol (Fig.…”

Section: Resultsmentioning

confidence: 92%

“…2 (27) and x-ray diffraction (25) that lysoPC forms lamellar structures with 40-80 mol% Chol. The formation of lamellar structures by equimolar lysoPC and Chol was confirmed by differential scanning calorimetry (24), x-ray diffraction (25) and barrier property measurements (11,32), and NMR spectroscopy (9,10,28). Experimental data and theoretical predictions are in agreement with each other in regard to the amount of Chol necessary for bilayer formation by lysoPC.…”

Section: Resultsmentioning

confidence: 99%

“…It has also been shown experimentally that molecules having complementary molecular shapes can form bilayer structures. Inverted cone (wedge)-shaped lysoPC and cone-shaped Chol or unsaturated PE can interact stoichiometrically to form bilayer structures (9)(10)(11)(12).…”

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confidence: 99%

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Complementary molecular shapes and additivity of the packing parameter of lipids.

Kumar

1991

Proc. Natl. Acad. Sci. U.S.A.

168

132

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Physical dimensions of a membrane component influence its phase preference upon hydration. A dimensionless packing parameter, S, given by S = V/al, where V is the hydrocarbon volume, a is the area of the head group, and I is the critical length of the hydrocarbon chain, is useful in determining the phase preference of a lipid, and the value of S usually lies between 0.5 and 1 for bilayers. Here, the value of S is calculated for phosphatidylcholine (PC) and lysophosphatidylcholine (lysoPC) as a function of chain length, and it is shown that diacylPC having an S value of <0.74 does not form bilayers. For example, diacylPC, up to a chain length of eight carbon atoms, forms only micelles, whereas higher homologs with S > 0.74 form bilayers. It is also shown that when lipid molecules having complementary shapes associate, the value of S becomes additive. Using the additivity of S, a number of experimental results for lipid mixtures can be explained. For example, lysoPC and cholesterol form lamellar structures between 45 and "40 mol% cholesterol, and the additive value of S for this region is between 0.74 and 1. Similarly, the additivity of S shows that the maximum amount of cholesterol that can be incorporated into PC bilayers is 50 mol%, in agreement with experimental studies.Molecular shape is an important consideration in membrane modeling. Based on the physical dimensions of a membrane component, its phase presence upon hydration and its location in the membrane can often be predicted. Taking into account interaction free energies, molecular geometry, and entropy, theoreticians have developed a dimensionless packing parameter, S, that is useful in determining the size and shape of lipid aggregates. S is given by S = V/al, where V is the hydrocarbon volume, a is the area of head group, and 1 is the critical length of the hydrocarbon chain (1-3). a, V, and I are all estimable or measurable (4), and the value of S can be calculated. The value of S determines the aggregate formed by lipids or any amphiphiles upon hydration. It has been shown that lipids aggregate to form spherical micelles (S

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Effects of nonionic amphiphiles at sublytic concentrations on the erythrocyte membrane

Isomaa

Hägerstrand

1988

Cell Biochemistry & Function

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The interactions of octaethyleneglycol alkylethers (C10-C16), pentaethyleneglycol dodecylether, and dodecyl D-maltoside with the human erythrocyte membrane were studied. All the amphiphiles protected erythrocytes against hypotonic haemolysis. At concentrations where the amphiphiles protected erythrocytes against hypotonic haemolysis they reduced phosphate efflux. The potency of the amphiphiles, at equiprotecting concentrations, was correlated negatively to the length of the alkyl chain. Potassium fluxes were increased by all the amphiphiles at protective concentrations. The relative potency of the amphiphiles varied but it was not simply related to the length of the alkyl chain. The only amphiphile affecting active potassium influx was octaethyleneglycol decylether which induced a slight decrease. It is concluded that the increase in passive cation fluxes caused by the amphiphiles is due to an increased permeability of the lipid bilayer induced through a nonspecific interaction of the amphiphiles with the bilayer. The effect of the amphiphiles on ion transport mediated by membrane proteins is proposed to be due to an alteration of the state of the transporting protein.

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Effects of lysophosphatidylcholines on phosphatidylcholine and phosphatidylcholine/cholesterol liposome systems as revealed by 31P-NMR, electron microscopy and permeability studies

Cited by 147 publications

References 29 publications

Importance of the tryptophans of gramicidin for its lipid structure modulating activity in lysophosphatidylcholine and phosphatidylethanolamine model membranes. A comparative study employing gramicidin analogs and a synthetic α-helical hydrophobic polypeptide

Importance of the tryptophans of gramicidin for its lipid structure modulating activity in lysophosphatidylcholine and phosphatidylethanolamine model membranes. A comparative study employing gramicidin analogs and a synthetic α-helical hydrophobic polypeptide

Complementary molecular shapes and additivity of the packing parameter of lipids.

Effects of nonionic amphiphiles at sublytic concentrations on the erythrocyte membrane

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