TY - JOUR

T1 - Intrinsic molecules in lipid membranes change the lipid-domain interfacial area

T2 - cholesterol at domain interfaces

AU - Cruzeiro-Hansson, Leonor

AU - Ipsen, John Hjort

AU - Mouritsen, Ole G.

PY - 1989

Y1 - 1989

N2 - A theoretical analysis of the effects of intrinsic molecules on the lateral density fluctuations in lipid bilayer membranes is carried out by means of computer simulations on a microscopic interaction model of the gel-to-fluid chain-melting phase transition. The inhomogeneous equilibrium structures of gel and fluid domains, which in previous work (Cruzerio-Hansson, L. and Mouritsen, O.G. (1988) Biochim. Biophys. Acta 944, 63-72) were shown to characterize the transition region of pure lipid membranes, are here shown to be enhanced by intrinsic molecules such as cholesterol. Cholesterol is found to increase the interfacial area and to accumulate in the interfaces. The interfacial area, the average cluster size, the lateral compressibility, and the membrane area are calculated as functions of temperature and cholesterol concentration. It is shown that the enhancement by cholesterol of the lateral density fluctuations and the lipid-domain interfacial area is most pronounced away from the transition temperature. The implications of the results are discussed in relation to passive ion permeability and function of interfacially active enzymes such as phospholipase.

AB - A theoretical analysis of the effects of intrinsic molecules on the lateral density fluctuations in lipid bilayer membranes is carried out by means of computer simulations on a microscopic interaction model of the gel-to-fluid chain-melting phase transition. The inhomogeneous equilibrium structures of gel and fluid domains, which in previous work (Cruzerio-Hansson, L. and Mouritsen, O.G. (1988) Biochim. Biophys. Acta 944, 63-72) were shown to characterize the transition region of pure lipid membranes, are here shown to be enhanced by intrinsic molecules such as cholesterol. Cholesterol is found to increase the interfacial area and to accumulate in the interfaces. The interfacial area, the average cluster size, the lateral compressibility, and the membrane area are calculated as functions of temperature and cholesterol concentration. It is shown that the enhancement by cholesterol of the lateral density fluctuations and the lipid-domain interfacial area is most pronounced away from the transition temperature. The implications of the results are discussed in relation to passive ion permeability and function of interfacially active enzymes such as phospholipase.

KW - Cholesterol

KW - Density fluctuation

KW - Heterogeneity

KW - Interface active molecule

KW - Lateral compressibility

KW - Lipid bilayer

KW - Phase transition

U2 - 10.1016/0005-2736(89)90432-X

DO - 10.1016/0005-2736(89)90432-X

M3 - Journal article

C2 - 2647144

AN - SCOPUS:0024503870

VL - 979

SP - 166

EP - 176

JO - B B A - Biomembranes

JF - B B A - Biomembranes

SN - 0005-2736

IS - 2

ER -