Interaction of Phenylalanine with DPPC membranes by FTIR-ATR: influence of hydration

ROSA, A.S; DISALVO, E.A.; FRÍAS, M.A.

Buenos Aires

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

Sociedad Argentina de Biofísica

Amino acids are ubiquitously found in all living cells.Therefore, although they are usually only present in low concentrations in cells, amino acids represent interesting model substances to examining the interaction between amino acids and bilayer lipid membranes. Aromatic amino acids such as phenylalanine (Phe), has an aromatic ring of different characteristic sizes and hydrophilicity, which is expected to influence molecular arrangements, therefore, the polycondensation monolayers.According to results obtained with DPPC monolayers, Phe produces an association with the PC molecules which suggests a molecular interaction of the head groups with Phe residues at different hydration states .FTIR results indicate that the symmetric stretching of the phosphate group, which is quite sensible to hydration, is affected in a great extent by Phe. Also, the water bands of the phospholipids are significantly modified. Topological changes may modify the exposure to water of different residues of the lipid molecules such as CH2 and carbonyl groups, to water affecting the Phe-PC interaction.