[Interaction of melittin with a model membrane in the presence of antibodies].

The method of fluorescence spectrofluorimetry has been applied to study the interaction of melittin at high and low ionic strength with the phosphatidylcholine model membrane in the presence of monospecific polyclonal and monoclonal antibodies against this peptide. The formation of antigen-antibody complex with the excess of the antigen is shown to decrease the leakage of calcein, a fluorescence dye. With the excess of antibodies the dye leakage is completely suppressed. This effect does not depend on the state of peptide aggregation before binding to the membrane. It is suggested that melittin antigenic determinants are located on the sites of peptide molecule which are necessary for its interaction with the membrane.