| DOI | Trouver le DOI : https://doi.org/10.1016/j.bbamem.2009.02.013 |
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| Auteur | Rechercher : Pan, Jianjun; Rechercher : Tieleman, D. Peter; Rechercher : Nagle, John F.; Rechercher : Kučerka, Norbert; Rechercher : Tristram-Nagle, Stephanie1 |
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| Affiliation | - Conseil national de recherches du Canada. Centre canadien de faisceaux de neutrons du CNRC
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| Format | Texte, Article |
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| Sujet | lipid bilayer; peptide; X-ray; structure; MD simulation; alamethicin |
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| Résumé | We study fully hydrated bilayers of two di-monounsaturated phospholipids diC18:1PC (DOPC) and diC22:1PC with varying amounts of alamethicin (Alm). We combine the use of X-ray diffuse scattering and molecular dynamics simulations to determine the orientation of alamethicin in model lipids. Comparison of the experimental and simulated form factors shows that Alm helices are inserted transmembrane at high humidity and high concentrations, in agreement with earlier results. The X-ray scattering data and the MD simulations agree that membrane thickness changes very little up to 1/10 Alm/DOPC. In contrast, the X-ray data indicate that the thicker diC22:1PC membrane thins with added Alm, a total decrease in thickness of 4 Å at 1/10 Alm/diC22:1PC. The different effect of Alm on the thickness changes of the two bilayers is consistent with Alm having a hydrophobic thickness close to the hydrophobic thickness of 27 Å for DOPC; Alm is then mismatched with the 7 Å thicker diC22:1PC bilayer. The X-ray data indicate that Alm decreases the bending modulus (KC) by a factor of ∼ 2 in DOPC and a factor of ∼ 10 in diC22:1PC membranes (P/L ∼ 1/10). The van der Waals and fluctuational interactions between bilayers are also evaluated through determination of the anisotropic B compressibility modulus. |
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| Date de publication | 2009-02-25 |
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| Maison d’édition | Elsevier |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 23004478 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | 3c92640e-01ce-4540-b162-fda75f521ff0 |
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| Enregistrement créé | 2018-11-08 |
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| Enregistrement modifié | 2020-04-16 |
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