Study of the interaction of L-Cysteine and its esters with monolayers of DPPC

ARIAS, JUAN MARCELO; DUPUY, FERNANDO; TUTTOLOMONDO, MARÍA EUGENIA; DÍAZ, SONIA BEATRIZ; BEN ALTABEF, AÍDA

Santiago del Estero

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Biofísica; 2015

Sociedad Argentina de Biofísica

Cysteine is the aminoacid which has a thiol group and that takes part in a variety of biochemical reactions. In this work we studied a number of members of the cysteine family (L-cysteine, L-cysteine ethyl ester, L-cysteine methyl ester and N-acetyl cysteine) to understand their interaction with lipid membranes. The technique of Langmuir monolayers was used in order to study the surface behaviour of the different cysteine derivatives and their interaction with films made with the phospholipid DPPC. The change in the surface tension was measured whilst keeping molecular density and lateral packing controlled. The results indicate that, although the different derivatives of cysteine presented low surface activity, they were able to favourably interact with DPPC monolayers. Also, experiments in binary mixtures indicate that the more surface active compounds stabilized the gel phase of DPPC.