INFLUENCE OF MULTIBODY INTERACTIONS ON LIPID MEMBRANE MODELS

PENA AUSAR JOAQUIN; LEDESMA ANA ; PINTO O. A

Rosario , Santa FE

Congreso; Reunión Anual de la Sociedad Argentina de Biofísica; 2022

The lateral interactions between components of lipid membranes have been the object of study in numerous works through theoretical studies, in which it was sought to explain, for example, theself-assembly of membranes, cholesterol solubility in them and thermal phase transitions. It is understood from these works the important role that these interactions play as elements of models that allow us to explain and reproduce experimental systems.In the present work we focus on the study of the gel-fluid thermal transition of lipid membranes, in which the acyl chains go from an ordered state, that is, with low degeneration, to a disorderedstate with a greater number of possible orientations of carbon-carbon bonds.Previous works on the gel-fluid transition considered interactions calculated in pairs in a linear way, that is, not taking into account the effect of the interactions of more than two bodies. In thiswork, the effect of considering many-body interactions is studied by modifying the previous model, where we assume that the interaction energy of each pair depends on the environment of eachlipid. This was able to reproduce the results of the additive model but, unlike this, it was able to find new configurations of minimum energy in addition to the gel and pure fluid phases. Thecalculations of the variables of interest were carried out using Monte Carlo simulation.