Molecular insight into the line tension of bilayer membranes containing hybrid polyunsaturated lipids
| Autor: | Carla M. Rosetti, C. Pastorino, Guillermo G. Montich |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Work (thermodynamics) Lipid Bilayers Thermodynamics Molecular Dynamics Simulation 010402 general chemistry HYBRID LIPIDS 01 natural sciences 03 medical and health sciences Molecular dynamics Hydrophobic mismatch Membrane Microdomains Computational chemistry Materials Chemistry Physical and Theoretical Chemistry Chemistry Tension (physics) Bilayer Otras Ciencias Químicas Relaxation (NMR) Temperature Elastic energy Ciencias Químicas 0104 chemical sciences Surfaces Coatings and Films Cholesterol 030104 developmental biology Membrane LINE TENSION Phosphatidylcholines Hydrophobic and Hydrophilic Interactions CIENCIAS NATURALES Y EXACTAS |
| Popis: | Line tension (γ) is a key parameter for the structure and dynamics of membrane domains. It was proposed that hybrid lipids, with mixed saturated and unsaturated acyl chains, participate in the relaxation of γ through different mechanisms. In this work, we used molecular dynamics simulations of the coarse-grained MARTINI model to measure γ in liquid-ordered-liquid-disordered (Lo-Ld) membranes, with increasingly larger relative proportion of the hybrid polyunsaturated lipid PAPC (4:0-5:4PC) to DAPC (di5:4PC) (i.e., XH). We also calculated an elastic contribution to γ by the Lo-Ld thickness mismatch, tilt moduli, and bending moduli, as predicted by theory. We found that an increase in XH decreased the overall γ value and the elastic contribution to line tension. The effect on the elastic line tension is driven by a reduced hydrophobic mismatch. Changes in the elastic constants of the phases due to an increase in XH produced a slightly larger elastic γ term. In addition to this elastic energy, other major contributions to γ are found in these model membranes. Increasing XH decreases both elastic and nonelastic contributions to γ. Finally, PAPC also behaves as a linactant, relaxing γ through an interfacial effect, as predicted by theoretical results. This study gives insight into the actual contribution of distinct energy terms to γ in bilayers containing polyunsaturated hybrid lipids. Fil: Rosetti, Carla Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentina Fil: Montich, Guillermo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; Argentina Fil: Pastorino, Claudio. Comisión Nacional de Energía Atómica. Gerencia del Área Investigaciones y Aplicaciones no Nucleares; Argentina |
| Databáze: | OpenAIRE |
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