Surface behavior of ceramides with N-acyl chain of different length.

DUPUY, FERNANDO; FANANI, MARÍA LAURA; MAGGIO, BRUNO

Salta

Congreso; XXXIX Annual Meeting of Argentinean Biophysical Society SAB 2010, workshop CeBEM, structural biology in Latin America, 3rd Latin American Protein Society Meeting; 2010

Sociedad Argentina de Biofísica

Ceramides are sphingolipids contaning an amine-diol backbone, ussualy C18:1 sphingosine, N-acylated with fatty acids of different chain length and degree of unsaturation. When mixed with phospholipids or more complex sphingolipids, long chain ceramides form laterally segregated condensed domains. Short chain ceramides are widely used in cell biology studies and were found to mix with phospholipids. In this work, Langmuir monolayer studies of a series of ceramides N-acylated with fatty acids of different chain length were carried out, by measuring surface pressure, surface potential and reflectivity of p-polarized light of the lipids spread at the air-water interface. Liquid-expanded phases and condensed domains formation could be observed at 21ºC. The independent parameters measured indicate that both the morphology of the segregated condensed domains and their relative thickness are strongly dependent of the N-acyl chain.