Abstract
Cell membranes, which consist of a lipid bilayer, play a critical role in cellular bioactivities. The lipid bilayer interacts dynamically with water as well as ions. Membrane fluidity is lesser in ionic solutions than in pure water, although how ions reduce membrane fluidity has not yet been clarified. Here, we performed 4×100-ns molecular dynamics simulations of a POPE (1-palmitoyl-2-oleoyl-phosphatidyl-ethanolamine [18:1]) lipid bilayer in the presence or absence of ions (NaCl, KCl, or CaCl2) and compared the systems to evaluate the influence of ions on the structural dynamics of membranes. Our simulation revealed that membrane fluidity (no ion-system>Ca-system>K-system>Na-system) did not correspond to the distribution or the direct binding of cations to lipids (Ca2+>Na+>K+). Interestingly, we found that the presence of cations induces dehydration of lipids. The number of cations in the interface region corresponded to the degree of lipid dehydration and the reduction in membrane fluidity (Na+>K+>Ca2+). We therefore propose that membrane fluidity is not affected by direct interactions between cations and lipids, but by the dehydration of lipid molecules in the presence of cations located adjacent to the membrane.
| Original language | English |
|---|---|
| Pages (from-to) | 130-136 |
| Number of pages | 7 |
| Journal | Journal of Membrane Science |
| Volume | 435 |
| DOIs | |
| Publication status | Published - 2013 May 5 |
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Keywords
- Dynamic interactions of cations
- Lipid molecule
- Molecular dynamics simulation
- Water and lipids
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Materials Science(all)
- Biochemistry
- Filtration and Separation
Cite this
Dynamic interactions of cations, water and lipids and influence on membrane fluidity. / Kagawa, Rina; Hirano, Yoshinori; Taiji, Makoto; Yasuoka, Kenji; Yasui, Masato.
In: Journal of Membrane Science, Vol. 435, 05.05.2013, p. 130-136.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Dynamic interactions of cations, water and lipids and influence on membrane fluidity
AU - Kagawa, Rina
AU - Hirano, Yoshinori
AU - Taiji, Makoto
AU - Yasuoka, Kenji
AU - Yasui, Masato
PY - 2013/5/5
Y1 - 2013/5/5
N2 - Cell membranes, which consist of a lipid bilayer, play a critical role in cellular bioactivities. The lipid bilayer interacts dynamically with water as well as ions. Membrane fluidity is lesser in ionic solutions than in pure water, although how ions reduce membrane fluidity has not yet been clarified. Here, we performed 4×100-ns molecular dynamics simulations of a POPE (1-palmitoyl-2-oleoyl-phosphatidyl-ethanolamine [18:1]) lipid bilayer in the presence or absence of ions (NaCl, KCl, or CaCl2) and compared the systems to evaluate the influence of ions on the structural dynamics of membranes. Our simulation revealed that membrane fluidity (no ion-system>Ca-system>K-system>Na-system) did not correspond to the distribution or the direct binding of cations to lipids (Ca2+>Na+>K+). Interestingly, we found that the presence of cations induces dehydration of lipids. The number of cations in the interface region corresponded to the degree of lipid dehydration and the reduction in membrane fluidity (Na+>K+>Ca2+). We therefore propose that membrane fluidity is not affected by direct interactions between cations and lipids, but by the dehydration of lipid molecules in the presence of cations located adjacent to the membrane.
AB - Cell membranes, which consist of a lipid bilayer, play a critical role in cellular bioactivities. The lipid bilayer interacts dynamically with water as well as ions. Membrane fluidity is lesser in ionic solutions than in pure water, although how ions reduce membrane fluidity has not yet been clarified. Here, we performed 4×100-ns molecular dynamics simulations of a POPE (1-palmitoyl-2-oleoyl-phosphatidyl-ethanolamine [18:1]) lipid bilayer in the presence or absence of ions (NaCl, KCl, or CaCl2) and compared the systems to evaluate the influence of ions on the structural dynamics of membranes. Our simulation revealed that membrane fluidity (no ion-system>Ca-system>K-system>Na-system) did not correspond to the distribution or the direct binding of cations to lipids (Ca2+>Na+>K+). Interestingly, we found that the presence of cations induces dehydration of lipids. The number of cations in the interface region corresponded to the degree of lipid dehydration and the reduction in membrane fluidity (Na+>K+>Ca2+). We therefore propose that membrane fluidity is not affected by direct interactions between cations and lipids, but by the dehydration of lipid molecules in the presence of cations located adjacent to the membrane.
KW - Dynamic interactions of cations
KW - Lipid molecule
KW - Molecular dynamics simulation
KW - Water and lipids
UR - http://www.scopus.com/inward/record.url?scp=84875268724&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875268724&partnerID=8YFLogxK
U2 - 10.1016/j.memsci.2013.02.006
DO - 10.1016/j.memsci.2013.02.006
M3 - Article
AN - SCOPUS:84875268724
VL - 435
SP - 130
EP - 136
JO - Jornal of Membrane Science
JF - Jornal of Membrane Science
SN - 0376-7388
ER -