Negatively cooperative binding of melittin to neutral phospholipid vesicles

Torrens, Francisco; Castellano, Gloria; Campos, Agustı́n; Abad, Concepción

doi:10.1016/j.molstruc.2006.11.052

Cited by 18 publications

(7 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We therefore interpret the Hill coefficients from our fits (0.5) to indicate not anti-cooperativity but instead structural heterogeneity at the interface (as observed in atomistic molecular dynamics simulations, see below), a common alternate reason for Hill coefficients smaller than unity. 87 , 89 …”

Section: Resultsmentioning

confidence: 99%

Counting charges on membrane-bound peptides

et al. 2018

View full text Add to dashboard Cite

Quantifying the number of charges on peptides bound to interfaces requires reliable estimates of (i) surface coverage and (ii) surface charge, both of which are notoriously difficult parameters to obtain, especially at solid/water interfaces. Here, we report the thermodynamics and electrostatics governing the interactions of l-lysine and l-arginine octamers (Lys8 and Arg8) with supported lipid bilayers prepared.

show abstract

Section: Resultsmentioning

confidence: 99%

Counting charges on membrane-bound peptides

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Generally, with neutral membranes, the water-membrane partition coefficient for melittin increases with increasing ionic strength of the medium and decreases with increasing temperature. 39 In terms of lipid composition, partition coefficients in the fluid phase (above T m ) decrease in the order DPPC > DMPC >> DOPC > POPC > DOPC/chol > POPC/chol, with values ranging from K p =10 5 M -1 for DPPC to K p =10 3 M -1 (at 50 °C) for POPC/chol. 32,39 It is clear by examination of the data in Figs 2-4 and Table 1 that there is no simple correlation between lipidation activity and membrane binding affinity.…”

Section: Discussionmentioning

confidence: 99%

“…For practical (chromatographic) reasons, a value for the total peptide to lipid ratio (P t :L) of 1:10 was used for all experiments. At the absolute peptide and lipid concentrations used and considering available water-membrane partition coefficient (K p ) data, 39 the highest experimental value for P b /L was predicted to be 0.08 for DMPC. At this P b /L a significant proportion of melittin bound to DMPC LUVs was expected to be in the I state.…”

Section: Discussionmentioning

confidence: 99%

The influence of cholesterol on melittin lipidation in neutral membranes

Britt

Mosely

Sanderson

2019

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…33 When n < 1, anti-cooperative behavior is observed, meaning the affinity for binding decreases with an increasing concentration of adsorbate. Alternatively, adsorption to structurally or chemically heterogeneous surfaces can also result in artificially low n values 34,35 while electrostatics and reductions in dimensionality can explain high values for n. 36 In the work discussed here, the combined Gouy-Chapman/Langmuir and the Gouy-Chapman/Hill models were used to extract the equilibrium binding constant, the free energy of adsorption, and the interfacial charge density and charge per adsorbed polycation or peptide.…”

Section: (1)mentioning

confidence: 99%

Electrostatics, Hydrogen Bonding, and Molecular Structure at Polycation and Peptide:Lipid Membrane Interfaces

Dalchand¹,

Cui²,

Geiger³

2019

Preprint

View full text Add to dashboard Cite

Polycation and peptide modified surfaces represent opportunities for developing potentially novel biocidal materials in a growing effort to combat bacterial resistance to traditional bactericides. It is well known that the positive charge of these compounds is crucial to their function in biofouling prevention and as antimicrobials, however, methods for quantifying the number of positive charges on surface-bound polycations and peptides are necessary in order to predict, control, and optimize the design and therefore, the utility of these compounds. This Spotlight on Applications reports on such an approach that combines second harmonic generation (SHG) spectroscopy, quartz crystal microbalance with dissipation monitoring (QCM-D), and atomistic simulations to obtain mechanistic insight into polycation-membrane interactions using supported lipid bilayers (SLBs) as our model system. We find that at high surface coverage, the large polycations we surveyed feature a considerably smaller percentage of ionization when compared to the smaller polycations and peptides. At these high charge densities, we suspect a pKa shift of the charged groups to lower charge-charge repulsion as well as the formation of a loop-like conformation such that less monomeric units form contact-ion pairs with the bilayer. Our sum frequency generation (SFG) spectroscopy results complement our understanding of the Dalchand et al.Page 2 polycation-membrane interaction. At a high density of the polycation poly (allylamine hydrochloride) (PAH), second-order spectral line shapes are consistent with the expulsion of interfacial water molecules possibly due to contact-ion pair formation between PAH and the lipid bilayer. This finding could be essential for understanding the underlying first steps of cell lysis and penetration by polycations and should be explored further.

show abstract

Negatively cooperative binding of melittin to neutral phospholipid vesicles

Cited by 18 publications

References 51 publications

Counting charges on membrane-bound peptides

Counting charges on membrane-bound peptides

The influence of cholesterol on melittin lipidation in neutral membranes

Electrostatics, Hydrogen Bonding, and Molecular Structure at Polycation and Peptide:Lipid Membrane Interfaces

Contact Info

Product

Resources

About