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 pteronyssinu s, has been identified and characterized from a lambda gt11 cDNA libra ry of the mite. IgE antibodies from the sera of allergic patients that recognise the cloned polypeptide bind to an similar to 26 kDa polypep tide on a Western blot of reduced mite polypeptides. Nucleotide sequen cing of the clone revealed a 219 amino acid open reading frame-encodin g 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 sequenc e databanks revealed a strong homology with glutathione S-transferases . The nucleotide sequence of the clone displayed a strong homology wit h the active glutathione binding site of glutathione transferases and contained all but one of the 19 positionally conserved amino acid resi dues found in glutathione transferases. The cloned polypeptide was exp ressed in Escherichia coli and affinity-purified on glutathione agaros e.