Cloning of cDNA encoding a soybean allergen, Gly m Bd 28K.
A cDNA clone encoding a soybean allergen, Gly m Bd 28K, has been isolated. The clone has a 1567-bp cDNA insert with a 1419-bp open reading frame and a 148-bp 3'-untranslated region, followed by a polyadenylation tail. The open reading frame was shown to encode a polypeptide composed of 473 amino acids. The chemically determined amino acid sequences of the peptides obtained from the allergen, including its N-terminal peptide, were shown to be contained in the N-terminal region of the amino acid sequence deduced from the cDNA, showing that the first half of the cDNA encodes the allergen with a preceding segment of 21 amino acids. The peptide fragment including the allergen was expressed as a fusion protein with glutathione S-transferase in Escherichia coli and immunoblotted with the sera of soybean-sensitive patients and the monoclonal antibody against the allergen. Furthermore, homology analyses demonstrate that the polypeptide for the cDNA exhibits high homology with the MP27/MP32 proteins in pumpkin seeds and the carrot globulin-like protein. This finding suggests that the polypeptide may consist of a 21-amino acid segment as a part of the signal peptide and the proprotein, which may be converted to two mature proteins, Gly m Bd 28K and a 23-kDa protein, during the development of soybean cotyledons.
Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University, Juboki 111, Soja 719-1197, Japan. htsuji@fhw.oka-pu.ac.jp
H
H
Tsuji
M
M
Hiemori
M
M
Kimoto
H
H
Yamashita
R
R
Kobatake
M
M
Adachi
T
T
Fukuda
N
N
Bando
M
M
Okita
S
S
Utsumi
D000485:Allergens / Q000235:genetics*; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006023:Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010940:Plant Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D030262:Soybean Proteins; D013025:Glycine max
D000485:Allergens; D052179:Antigens, Plant; D018076:DNA, Complementary; C107967:Gly m Bd 28K allergen, Glycine max; D006023:Glycoproteins; D010940:Plant Proteins; D030262:Soybean Proteins