Molecular Dynamics of Di-phamitoyl-phosphatidyl-choline Biomembranes in Ionic Solution: Adsorption of the Precursor Neurotransmitter Tryptophane

Microscopic structure of a fully hydrated di-palmytoil-phosphatidyl-choline lipid bilayer membrane in the liquid-crystalline phase has been analyzed with all-atom molecular dynamics simulations based on the recently parameterized CHARMM36 force field. Within the membrane, a single molecule of the a-...

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Bibliographic Details
Authors: Lu, Huixia|||0000-0003-2731-5283, Martí Rabassa, Jordi|||0000-0002-3721-9634
Format: article
Publication Date:2017
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/191990
Online Access:https://hdl.handle.net/2117/191990
https://dx.doi.org/10.1016/j.procs.2017.05.141
Access Level:Open access
Keyword:Membranes (Biology)
Ionization
Biomembranes
DPPC
Tryptophan
Neurotransmitter
Ionic aqueous solution
Membranes (Biologia)
Ionització
Àrees temàtiques de la UPC::Física
Description
Summary:Microscopic structure of a fully hydrated di-palmytoil-phosphatidyl-choline lipid bilayer membrane in the liquid-crystalline phase has been analyzed with all-atom molecular dynamics simulations based on the recently parameterized CHARMM36 force field. Within the membrane, a single molecule of the a-aminoacid tryptophan (precursor of important neurotransmitters such as serotonin and melatonin) has been embedded and its structure and binding sites to water and lipids have been explored. In addition, properties such as radial distribution functions, hydrogen-bonding, energy and pressure profiles and the potentials of mean force of water-tryptophan and lipid-tryptophan have been evaluated. It has been observed that tryptophan usually has a tendency to place itself close to the lipid headgroups but that it can be fully hydrated during short time intervals of the order of a few nanoseconds. This would indicate that, for tryptophan, both hydrophobic forces as well as the attraction to polar sites of the lipids play a significant role in the definition of its structure and binding states.