Antibodies raised against bovine beta-lactoglobulin react with beta 2-microglobulin. A possible antigenic region at beta-LG positions 124-140.
beta-Lactoglobulin is a major whey protein in bovine milk. Its presence has been demonstrated in all mammals examined except rodents and humans. However a positive cross reaction was observed for human milk proteins with antibodies raised against bovine beta-lactoglobulin. We isolated and characterized a protein fraction of ca. 12 kDa responsible for the positive cross reaction. N-terminal sequencing and amino-acid analysis indicated that this protein is identical with human beta 2-microglobulin. We observed structural homology between beta-lactoglobulin region 124-140 and beta 2-microglobulin 71-86, which suggested that positions 124-140 could be the antigenic region for beta-lactoglobulin. Six highly conserved amino-acid residues are suggested as candidates for the antigenic site.
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Centro Studi Alimentazione Animali, CNR, Torino.
Godovac-Zimmermann
J
J
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D003429:Cross Reactions; D000939:Epitopes / Q000032:analysis*; D006801:Humans; D007782:Lactoglobulins / Q000276:immunology*; D008969:Molecular Sequence Data; D013045:Species Specificity; D001613:beta 2-Microglobulin / Q000032:analysis / Q000276:immunology*
D000939:Epitopes; D007782:Lactoglobulins; D001613:beta 2-Microglobulin