Isolation and characterization of two antigenically active peptides from bovine β-lactoglobulin-A

摘要

Bovine β-lactoglobulin-A was hydrolysed with trypsin to yield a mixture of peptides which would not precipitate with rabbit antibody against the native protein, but would still inhibit the antigen—antibody reaction. The hydrolysate was fractionated by ion exchange chromatography and found to contain seven antigenically active fractions. Two of these fractions were found to be homogeneous peptides. Each inhibited the reaction of antigen with antibody against the intact protein in haemagglutination, flocculation and passive cutaneous anaphylaxis reaction in guinea-pigs. One of the peptides had a molecular weight of 950 and the other had a molecular weight of 575. Both contained about equal numbers of polar and apolar amino acids.