Characterization of the 18-kDa apple allergen by two-dimensional immunoblotting and microsequencing.
A low-temperature extract taken from Golden Delicious apples was separated by two-dimensional polyacrylamide gel electrophoresis. By means of two-dimensional immunoblotting with patients' serum containing IgE specific to Bet v I, a rabbit polyclonal antiserum raised against Bet v I, and two Bet v I specific monoclonal antibodies, epitopes cross-reactive to Bet v I were identified on an apple allergen with a molecular mass of 18 kDa and pI 5.5. Furthermore, certain antibody reactivities with 4 isoproteins of a molecular mass of 16 kDa and pIs ranging from 4.9 to 5.5 were observed, which may indicate the presence of Bet v I related epitopes on these proteins. Based on 26 amino acid residues, N-terminal sequencing of the 18-kDa apple allergen revealed 62% sequence identity between Bet v I from birch pollen and the apple allergen. Our results therefore support the view that both proteins express common as well as non-related IgE-reactive epitopes.
Vieths
S
S
Institute of Food Chemistry, Technische Universität Berlin, Germany.
Schöning
B
B
Petersen
A
A
D000485:Allergens / Q000032:analysis* / Q000235:genetics; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D003429:Cross Reactions; D015180:Electrophoresis, Gel, Two-Dimensional; D000939:Epitopes / Q000032:analysis; D005638:Fruit / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000032:analysis; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000032:analysis; D011058:Pollen / Q000737:chemistry; D017386:Sequence Homology, Amino Acid
D000485:Allergens; D052179:Antigens, Plant; D000939:Epitopes; D010940:Plant Proteins; C061312:Bet v 1 allergen, Betula; D007073:Immunoglobulin E