Isolation and molecular cloning of a major wheat allergen, Tri a Bd 27K

Biosci Biotechnol Biochem. 2009 Jan;73(1):85-92. doi: 10.1271/bbb.80485. Epub 2009 Jan 7.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allergens / chemistry*
  • Allergens / genetics
  • Allergens / isolation & purification
  • Amino Acid Sequence
  • Antigens, Plant / chemistry*
  • Antigens, Plant / genetics
  • Antigens, Plant / isolation & purification
  • Cloning, Molecular*
  • Fucose
  • Glycoproteins
  • Glycosylation
  • Humans
  • Molecular Weight
  • Triticum / immunology*


  • Allergens
  • Antigens, Plant
  • Glycoproteins
  • Tri a Bd 27K allergen, Triticum aestivum
  • Fucose