Isolation and molecular cloning of a major wheat allergen, Tri a Bd 27K.
Tri a Bd 27K is the predominant allergen in wheat. In the present study, this allergen was purified to homogeneity from wheat flour. The N-terminal amino acid sequences of the purified allergen and the peptides obtained by its digestion, with trypsin were determined, and the allergen was shown to be a glycoprotein with an Asn-linked sugar moiety containing fucose residues. A cDNA encoding the allergen was obtained by polymerase chain reaction (PCR). The cDNA codes for a protein of 203 amino acid residues, with a molecular mass of 22,803 Da, that has two tentative sites glycosylated at Asn residues. Homology analysis suggested that the allergen might belong to a family of gamma-interferon-inducible thiol reductases. The cDNA was expressed as a fusion protein with glutathione S-transferase in Escherichia coli. However, unlike the allergen purified from wheat, recombinant Tri a Bd 27K was not immunoblotted with IgE antibodies in the serum of a wheat-sensitive patient.
Kimoto
Masumi
M
Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University. kimoto@fhw.oka-pu.ac.jp
Suzuki
Makiko
M
Komiyama
Nobuko
N
Kunimoto
Ayumi
A
Yamashita
Hiromi
H
Hiemori
Miki
M
Takahashi
Kyoko
K
Tsuji
Hideaki
H
D000485:Allergens / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D000595:Amino Acid Sequence; D052179:Antigens, Plant / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular; D005643:Fucose; D006023:Glycoproteins; D006031:Glycosylation; D006801:Humans; D008970:Molecular Weight; D014908:Triticum / Q000276:immunology*
D000485:Allergens; D052179:Antigens, Plant; D006023:Glycoproteins; C539494:Tri a Bd 27K allergen, Triticum aestivum; D005643:Fucose