Molecular-level insight into the binding of arginine to a zwitterionic Langmuir monolayer
Solutions of the cationic amino-acid arginine (Arg+) in contact with a phospholipid monolayer are investigated by molecular dynamics simulations. The results show that Arg+ binds strongly to the lipid/water interface, with adsorption free-energies ranging from -43.8 to -22.2 kJ mol-1, depending on t...
| Autores: | , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2017 |
| País: | Argentina |
| Institución: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/49420 |
| Acceso en línea: | http://hdl.handle.net/11336/49420 |
| Access Level: | acceso abierto |
| Palabra clave: | MOLECULAR DYNAMICS LANGMUIR MONOLAYER ARGININE FREE ENERGY https://purl.org/becyt/ford/1.6 https://purl.org/becyt/ford/1 |
| Sumario: | Solutions of the cationic amino-acid arginine (Arg+) in contact with a phospholipid monolayer are investigated by molecular dynamics simulations. The results show that Arg+ binds strongly to the lipid/water interface, with adsorption free-energies ranging from -43.8 to -22.2 kJ mol-1, depending on the amino-acids concentration. The large binding energies are attributed to hydrogen bonding between the charged moieties Arg+ and the phosphate and carbonyl groups of the phospholipids, that compensate for changes in the levels of hydration upon adsorption. We show that a concentrated layer of Arg+, tightly bound to the interface, has little effect on the compression isotherm and the lateral mechanical properties of the monolayer, while having a substantial impact on the interfacial electrostatic potential and the lateral mobility of the lipids. These effects are readily explained in terms of the arrangement that the amino-acids adopt when bound to the monolayer. |
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