Nano-scale structure in membranes in relation to enzyme action—computer simulation vs. Experiment

TY - JOUR

T1 - Nano-scale structure in membranes in relation to enzyme action—computer simulation vs. Experiment

AU - Høyrup, Pernille

AU - Jørgensen, Kent

AU - Mouritsen, Ole G.

PY - 2002/8/1

Y1 - 2002/8/1

N2 - There is increasing theoretical and experimental evidence indicating that small-scale domain structure and dynamical heterogeneity develop in lipid membranes as a consequence of the the underlying phase transitions and the associated density and composition fluctuations. The relevant coherence lengths are in the nano-meter range. The nano-scale structure is believed to be important for controlling the activity of enzymes, specifically phospholipases, which act at bilayer membranes. We propose here a lattice-gas statistical mechanical model with appropriate dynamics to account for the non-equilibrium action of the enzyme phospholipase A2 which hydrolyses lipid-bilayer substrates. The resulting product molecules are assumed to induce local variations in the membrane interfacial pressure. Monte Carlo simulations of the non-equilibrium properties of the model for one-component as well as binary lipid mixtures show that the enzyme activity is modulated by nano-scale lipid-domain formation in the lipid bilayer and lead to a characteristic lag-burst behavior. The simulations are found to be in semi-quantitative agreement with experimental data.

AB - There is increasing theoretical and experimental evidence indicating that small-scale domain structure and dynamical heterogeneity develop in lipid membranes as a consequence of the the underlying phase transitions and the associated density and composition fluctuations. The relevant coherence lengths are in the nano-meter range. The nano-scale structure is believed to be important for controlling the activity of enzymes, specifically phospholipases, which act at bilayer membranes. We propose here a lattice-gas statistical mechanical model with appropriate dynamics to account for the non-equilibrium action of the enzyme phospholipase A2 which hydrolyses lipid-bilayer substrates. The resulting product molecules are assumed to induce local variations in the membrane interfacial pressure. Monte Carlo simulations of the non-equilibrium properties of the model for one-component as well as binary lipid mixtures show that the enzyme activity is modulated by nano-scale lipid-domain formation in the lipid bilayer and lead to a characteristic lag-burst behavior. The simulations are found to be in semi-quantitative agreement with experimental data.

KW - Computer simulation

KW - Domain formation

KW - Fluctuations

KW - Lipid bilayer

KW - Monte Carlo

KW - Non-equilibrium

KW - Phospholipase A

UR - http://www.scopus.com/inward/record.url?scp=0036681582&partnerID=8YFLogxK

U2 - 10.1016/S0010-4655(02)00294-1

DO - 10.1016/S0010-4655(02)00294-1

M3 - Journal article

AN - SCOPUS:0036681582

SN - 0010-4655

VL - 147

SP - 313

EP - 320

JO - Computer Physics Communications

JF - Computer Physics Communications

IS - 1-2

ER -