CLONING AND CHARACTERIZATION OF A MAJOR ALLERGEN OF THE HOUSE-DUST MITE, DERMATOPHAGOIDES-PTERONYSSINUS, HOMOLOGOUS WITH GLUTATHIONE-S-TRANSFERASE

A major allergen of the house dust mite, Dermatophagoides pteronyssinus, has been identified and characterized from a lambda gt11 cDNA library of the mite. IgE antibodies from the sera of allergic patients that recognise the cloned polypeptide bind to an similar to 26 kDa polypeptide on a Western blot of reduced mite polypeptides. Nucleotide sequencing of the clone revealed a 219 amino acid open reading frame-encoding a protein with a derived molecular mass of 25589 Da and a pi of 6.3. Comparison of the deduced amino acid sequence with amino acid sequence databanks revealed a strong homology with glutathione S-transferases. The nucleotide sequence of the clone displayed a strong homology with the active glutathione binding site of glutathione transferases and contained all but one of the 19 positionally conserved amino acid residues found in glutathione transferases. The cloned polypeptide was expressed in Escherichia coli and affinity-purified on glutathione agarose.