Vesicles of charged (Phosphatidic Acid) and neutral (Phosphatidylcholine) lipids were used as membranes model to examine the lateral phase separation induced by a globular protein, namely lysozyme. The ability of the positively charged protein, adsorbed onto vesicles surfaces, to induce the formation of micro-domains richer in the charged lipid component has been investigated by calorimetric measurements, using a DSC instrument. The protein adsorption, rate of denaturation and lipid micro-domains formation were affected by pH and salt concentration variations showing the deep influence of the electric charges in modulating this phenomena. Some of the present results have been rationalized on the basis of a theoretical model recently developed by the authors.
INTERACTION OF GLOBULAR-PROTEINS WITH MIXED LIPID VESICLES - A THERMODYNAMIC STUDY OF THE LIPID LATERAL PHASE-SEPARATION
RAUDINO, Antonio;CASTELLI, Francesco
1991-01-01
Abstract
Vesicles of charged (Phosphatidic Acid) and neutral (Phosphatidylcholine) lipids were used as membranes model to examine the lateral phase separation induced by a globular protein, namely lysozyme. The ability of the positively charged protein, adsorbed onto vesicles surfaces, to induce the formation of micro-domains richer in the charged lipid component has been investigated by calorimetric measurements, using a DSC instrument. The protein adsorption, rate of denaturation and lipid micro-domains formation were affected by pH and salt concentration variations showing the deep influence of the electric charges in modulating this phenomena. Some of the present results have been rationalized on the basis of a theoretical model recently developed by the authors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
