Effects of imidazolium-based ionic surfactants on the size and dynamics of phosphatidylcholine bilayers with saturated and unsaturated chains

Lee, Hwankyu

doi:10.1016/j.jmgm.2015.05.010

Cited by 7 publications

(6 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The N- and C-termini were respectively unprotonated and protonated to make them electrostatically neutral, matching the terminal charge state of the experimental peptides 16 . Potential parameters for dioleoylglycerophosphocholine (DOPC) and dioleoylglycerophosphoethanolamine (DOPE) lipids were taken from the Berger lipid FF 29 modified by Tieleman et al 30 , which can be compatibly used with the OPLS protein FF and has successfully predicted the experimentally observed areas per lipid and dynamics of DOPC and other phospholipid bilayers 31 32 33 . For cholesterol, we used potential parameters developed by Holtje et al 34 , which was converted to be used with the OPLS FF by Hub et al 35 …”

Section: Methodsmentioning

confidence: 99%

All-atom simulations and free-energy calculations of coiled-coil peptides with lipid bilayers: binding strength, structural transition, and effect on lipid dynamics

Woo

Lee

2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

Peptides E and K, which are synthetic coiled-coil peptides for membrane fusion, were simulated with lipid bilayers composed of lipids and cholesterols at different ratios using all-atom models. We first calculated free energies of binding from umbrella sampling simulations, showing that both E and K peptides tend to adsorb onto the bilayer surface, which occurs more strongly in the bilayer composed of smaller lipid headgroups. Then, unrestrained simulations show that K peptides more deeply insert into the bilayer with partially retaining the helical structure, while E peptides less insert and predominantly become random coils, indicating the structural transition from helices to random coils, in quantitative agreement with experiments. This is because K peptides electrostatically interact with lipid phosphates, as well as because hydrocarbons of lysines of K peptide are longer than those of glutamic acids of E peptide and thus form stronger hydrophobic interactions with lipid tails. This deeper insertion of K peptide increases the bilayer dynamics and a vacancy below the peptide, leading to the rearrangement of smaller lipids. These findings help explain the experimentally observed or proposed differences in the insertion depth, binding strength, and structural transition of E and K peptides, and support the snorkeling effect.

show abstract

Section: Methodsmentioning

confidence: 99%

All-atom simulations and free-energy calculations of coiled-coil peptides with lipid bilayers: binding strength, structural transition, and effect on lipid dynamics

Woo

Lee

2016

Sci Rep

Self Cite

View full text Add to dashboard Cite

show abstract

“…To model the charge states at higher pH, 50%-protonated and completely unprotonated PLLs were also generated (Table 1). For palmitoyloleoylglycerophosphocholine (POPC) lipids, potential parameters were taken from the Berger lipid FF, 59 which was modified to be compatible with the OPLS FF by Tieleman et al 60 With this modified lipid FF and TIP4P water, we previously equilibrated lipid bilayers, showing the area per lipid of 62.3 (AE1.5), 64.6 (AE0.2), and 67.7 (AE0.2) Å 2 , respectively, for DMPC, POPC, and DOPC bilayers, 61 which agree well with the experimental values of 59.9 (DMPC), 64.3 (POPC), and 67.4 Å 2 (DOPC) at 303 K. 62,63 Also, we calculated lateral diffusion coefficients of those bilayers, showing 0.81 (AE0.07), 0.69 (AE0.1), and 0.74 (AE0.1) Â 10 À7 cm 2 s À1 , respectively, for DMPC, POPC, and DOPC bilayers, 61,64 which favorably compare with the experimental values of 1.0, 0.78, and 0.82 Â 10 À7 cm 2 s À1 . 65,66 These indicate that simulations using this FF can successfully reproduce the experimentally observed areas per lipid and lateral diffusivities of lipids.…”

Section: Methodsmentioning

confidence: 99%

Effects of temperature, salt concentration, and the protonation state on the dynamics and hydrogen-bond interactions of polyelectrolyte multilayers on lipid membranes

Lee

2016

Phys. Chem. Chem. Phys.

Self Cite

View full text Add to dashboard Cite

Polyelectrolyte multilayers, which consist of poly-l-lysines (PLL) and hyaluronic acids (HA), are simulated on phospholipid membranes with explicit water at different temperatures, salt concentrations, and protonation states of PLL that correspond to pH 7 or higher. PLL and HA polymers, which are initially sequentially deposited as three HA/PLL bilayers above the membrane, partially intermix with each other within 300 ns, and with a significant amount of water at almost half of its bulk density. With reduced protonation of amine groups of PLL, the polymers diffuse faster, especially at higher temperatures, and for 0%-protonation, disperse into the water, due to the many fewer hydrogen bonds between PLL and HA polymers. When PLL is protonated, the addition of salt ions weakens electrostatic interactions between PLL and HA and, at 0.5 M NaCl, eventually reduces the number of hydrogen bonds, which in experiments leads to hole formation inside the PLL/HA film. Multilayers are stabilized by hydrogen bonds, primarily between charged groups and to a lesser extent between uncharged groups. PLL and HA also electrostatically interact with lipid head groups of membranes which reduces the lateral mobility of membrane lipids, to an extent dependent on the salt concentration. These findings help quantitate the effects of temperature, salt, and the protonation state (or pH) on the stability and dynamics of multilayers and membranes, and show trends that compare favorably with the experimental observations of the swelling of multilayers.

show abstract

“…Consequences of IL membrane disruption increase membrane fluidity (e.g., ionic surfactant) (23, 49) and impose lateral pressure on the membrane (50, 62) as evidenced by cavities, dents, and wrinkles in SEM images (Fig. 3C, 3E, 3G) and dramatic remodeling of lipids in Y. lipolytica (Fig.…”

Section: Discussionmentioning

confidence: 99%

Exceptional Solvent Tolerance inYarrowia lipolyticaIs Enhanced by Sterols

Walker

Ryu

Trinh

2018

Preprint

View full text Add to dashboard Cite

7Microbial biocatalysis in organic solvents such as ionic liquids (ILs) is attractive for making fuels and transcriptomics to elucidate this unique phenotype, we discovered that both wildtype Y. 19lipolytica and YlCW001 reconfigured membrane composition (e.g., glycerophospholipids and 20 sterols) and cell wall structure (e.g., chitin) under IL-stressful environments. By probing the steroid 21 pathway at transcriptomic, enzymatic, and metabolic levels, we validated that sterols (i.e.,

show abstract

Effects of imidazolium-based ionic surfactants on the size and dynamics of phosphatidylcholine bilayers with saturated and unsaturated chains

Cited by 7 publications

References 54 publications

All-atom simulations and free-energy calculations of coiled-coil peptides with lipid bilayers: binding strength, structural transition, and effect on lipid dynamics

All-atom simulations and free-energy calculations of coiled-coil peptides with lipid bilayers: binding strength, structural transition, and effect on lipid dynamics

Effects of temperature, salt concentration, and the protonation state on the dynamics and hydrogen-bond interactions of polyelectrolyte multilayers on lipid membranes

Exceptional Solvent Tolerance inYarrowia lipolyticaIs Enhanced by Sterols

Contact Info

Product

Resources

About