TY - JOUR
T1 - Lactoferrin-derived antimicrobial peptide induces a micellar cubic phase in a model membrane system
AU - Bastos, M.
AU - Silva, T.
AU - Teixeira, V.
AU - Nazmi, K.
AU - Bolscher, J.G.M.
AU - Funari, S.S.
AU - Uhríková, D.
PY - 2011
Y1 - 2011
N2 - The observation of a micellar cubic phase is reported for a mixture of an antimicrobial peptide from the Lactoferrin family, LFampin 265-284, and a model membrane system of dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol (3:1), as derived from small-angle x-ray diffraction (SAXD) measurements. The system shows remarkable thermotropic polymorphism: the peptide disrupts the lipid bilayer, forming a cubic phase of the space group Pm3n (t < 28°C), and as the temperature increases it shows a complex phase behavior (not fully clarified by SAXD). The onset, volume fraction of each phase, and phase parameters are seen to vary with peptide/lipid ratio and temperature. The obtained SAXD data represent the first experimental evidence, to our knowledge, of a micellar cubic phase in the context of antimicrobial peptide/membrane interaction. We propose that the micellization of the membrane according to the carpet model, for long proposed as a possible mechanism of action, can go through the formation of a cubic micellar phase.
AB - The observation of a micellar cubic phase is reported for a mixture of an antimicrobial peptide from the Lactoferrin family, LFampin 265-284, and a model membrane system of dimyristoylphosphatidylcholine/dimyristoylphosphatidylglycerol (3:1), as derived from small-angle x-ray diffraction (SAXD) measurements. The system shows remarkable thermotropic polymorphism: the peptide disrupts the lipid bilayer, forming a cubic phase of the space group Pm3n (t < 28°C), and as the temperature increases it shows a complex phase behavior (not fully clarified by SAXD). The onset, volume fraction of each phase, and phase parameters are seen to vary with peptide/lipid ratio and temperature. The obtained SAXD data represent the first experimental evidence, to our knowledge, of a micellar cubic phase in the context of antimicrobial peptide/membrane interaction. We propose that the micellization of the membrane according to the carpet model, for long proposed as a possible mechanism of action, can go through the formation of a cubic micellar phase.
U2 - 10.1016/j.bpj.2011.06.038
DO - 10.1016/j.bpj.2011.06.038
M3 - Article
SN - 0006-3495
VL - 101
SP - L20-L22
JO - Biophysical Journal
JF - Biophysical Journal
IS - 3
ER -