Phenyalanine lipid membrane interaction assessed by surface pressure studies

MATURANA, P.; CEJAS, J.P.; FRIAS, M DE LOS ANGELES; CUTRO, ANDREA C.; HOLLMANN, AXEL; DISALVO, E ANIBAL

Sierra de la Ventana

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Biofísica; 2014

Sociedad Argentina de Biofísica

Small amphyphilic molecules may partition in lipid membranes, among them, aromatic amino acids such as Tyr, Trp and Phe have an amphiphilic character due to the hydrophobicity of the indol and phenyl rings (1). In particular, Phe has been shown to damage thylakoid membranes at very low concentrations during freezing. Also, in liposomes, it also induces leakage and membrane fusion (2). Apparently, at relatively low concentrations the damage is produced on membranes under stress conditions, i.e. partial dehydration. Many amphiphilic compounds may protect membranes from oxidative stress under conditions of low water availability. Therefore, the influence of aminoacids such as Phe on the stability of membranes can be regulated by the water stress. It is well known that water/lipid ratio can be modified in lipid monolayers by changing the surface pressure.