Interacción de Proteína Básica que une ácidos grasos con membranas lipídicas

MARÍA VERÓNICA NOLAN, MASSIMILIANO PERDUCA, HUGO MÓNACO, BRUNO MAGGIO Y GUILLERMO MONTICH

Campinhas

Congreso; IV Congreso de Biofísica del Cono Sur,; 2000

Sociedades argentina y brasilera de Biofísica

We have studied the interaction of ChL-FABP with POPC and POPG. At low ionic strength, a filtration assay indicates that  ChL-FABP binds to POPG LUVs but not to POPC. According to the shift in the absorption spectra of the single trp, ChL-FABP pure or in the presence of POPC unfolds at 60°C. Oppostite spectral shift are observed in the presence of POPG, probably because the protein is already partly unfolded in the POPG membrane. When bound to POPG at 25°C, FT-IR spectroscopy indicates a loss of b-structure; rthis change occurs without changes in the Trp environment according to the fluorescence emision spectra. In the presence of 0.1 M NaCl we have not detected binding to POPC or to POPG LUVs. These  results suggest that both hidrophobic and electrostatic interactions are involved in the binding of ChL-FABP to membranes.