THE AMINO-ACID-SEQUENCE OF OLE-E I, THE MAJOR ALLERGEN FROM OLIVE TREE (OLEA-EUROPAEA) POLLEN

The complete primary structure of the major allergen from Olea europae a (olive tree) pollen, Ole e I (IUIS nomenclature), has been determine d. The amino acid sequence was established by automated Edman degradat ion of the reduced and alkylated molecule as well as of selected fragm ents obtained by proteolytic digestions. Ole e I contains a single pol ypeptide chain of 145 amino acid residues with a calculated molecular mass of 16331 Da. No free sulfhydryl groups have been detected in the native protein. The molecule contains a putative glycosylation site. A high degree of microheterogeneity has been observed, mainly centered in the first 33% of the molecule. Comparison of Ole e I sequence with protein sequence databases showed no similarity with other known aller gens. However, it has a 36% and 38% sequence identity with the putativ e polypeptide structures, deduced, respectively, from nucleotide seque nces of genes isolated from tomato anthers and com pollen, which have been suggested to be involved in the growing of the pollen tube. There fore, the olive tree allergen may be a constitutive protein of the pol len involved in reproductive functions.