Ole e 3, an olive-tree allergen, belongs to a widespread family of pollen proteins.
An allergen has been isolated from a saline extract of olive tree (Olea europaea) pollen. The protein consists of a single polypeptide chain of 9.2-kDa, as determined by mass spectrometry. It contains neither tryptophan nor tyrosine residues, and displays an acidic isoelectric point. The secondary structure of the protein, estimated from the analysis of the circular-dichroism spectrum in the peptide-bond region, is composed of 52% alpha-helix, 10% beta-strand, 29% beta-turn and 9% non-regular conformation. The N-terminal end of the protein is blocked. Amino-acid-sequence data have been obtained from peptides produced by CNBr treatment of the native allergen. A partial sequence of 36 amino acids has thus been elucidated. The protein exhibits sequence similarity with pollen allergens from Brassica species and contains a Ca(2+)-binding motif. The isolated protein displays IgE-binding activity against sera of patients allergic to olive-tree pollen. It has been named Ole e 3, according to the recommendations of the IUIS Nomenclature Committee. IgG ELISA inhibition assays with polyclonal antibodies specific for Ole e 3 reveal the presence of proteins similar to Ole e 3 in the pollen from non-related plant species, which may explain allergic cross-reactivity processes.
Batanero
E
E
Departamento de Bioquímica y Biología Molecular, Facultad de Química, Universidad Complutense, Madrid, Spain.
Villalba
M
M
Ledesma
A
A
Puente
X S
XS
Rodríguez
R
R
D000485:Allergens; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000941:Antigens; D052179:Antigens, Plant; D002135:Calcium-Binding Proteins; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D005638:Fruit / Q000737:chemistry / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity; D007525:Isoelectric Focusing; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000737:chemistry* / Q000276:immunology; D011058:Pollen / Q000737:chemistry* / Q000276:immunology; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014197:Trees / Q000737:chemistry / Q000276:immunology
D000485:Allergens; D000596:Amino Acids; D000941:Antigens; D052179:Antigens, Plant; D002135:Calcium-Binding Proteins; C102722:OLE3 protein, Olea europaea; D010940:Plant Proteins