| DOI | Resolve DOI: https://doi.org/10.1016/j.bbamem.2009.02.013 |
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| Author | Search for: Pan, Jianjun; Search for: Tieleman, D. Peter; Search for: Nagle, John F.; Search for: Kučerka, Norbert; Search for: Tristram-Nagle, Stephanie1 |
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| Affiliation | - National Research Council of Canada. NRC Canadian Neutron Beam Centre
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| Format | Text, Article |
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| Subject | lipid bilayer; peptide; X-ray; structure; MD simulation; alamethicin |
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| Abstract | 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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| Publication date | 2009-02-25 |
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| Publisher | Elsevier |
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| In | |
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| Language | English |
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| Peer reviewed | Yes |
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| NPARC number | 23004478 |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | 3c92640e-01ce-4540-b162-fda75f521ff0 |
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| Record created | 2018-11-08 |
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| Record modified | 2020-04-16 |
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