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

JUAN MARCELO ARIAS; FERNANDO G. DUPUY; ME. E. TUTTOLOMONDO; SONIA B. DÍAZ; AIDA BEN ALTABEF

Santiago del Estero

Congreso; SAB2015; 2015

SAB

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