title: Molecular cloning and characterization of the major allergen Myr p II from the venom of the jumper ant Myrmecia pilosula: Myr p I and Myr p II share a common protein leader sequence.
abstract: A major allergen Myr p II of the Australian jumper ant Myrmecia pilosula has been cloned, immunocharacterized and nucleotide sequenced. An open reading frame of 225 bases was identified and found to encode a deduced amino acid sequence of 75 residues which contained a typical hydrophobic peptide leader sequence. Expressed fusion proteins of Myr p II in both phage and plasmid vectors bind high levels of ant venom-specific IgE and the expressed clones are recognised by 35% of ant venom-allergic individuals. IgE antibodies that recognise the expressed clone have been shown to recognise IgE-binding bands in blots of native venom after separation by SDS-PAGE. The amino acid sequence of Myr p II shares close structural homology with the other major jumper ant allergen Myr p I, differing by only three amino acids in the first 47 residues of both sequences. However, N-terminal analysis of IgE-binding bands derived from Tricine-SDS-PAGE gel blots indicates that both Myr p I and Myr p II undergo extensive post-translational proteolytic processing to unique peptides of 45 and 27 residues, respectively.
authors.affiliation: Molecular Immunology Unit, Kolling Institute of Medical Research, Royal North Shore Hospital of Sydney, St. Leoonards, NSW, Australia.
authors.forename: M D
authors.initials: MD
authors.lastname: Street
authors.forename: G R
authors.initials: GR
authors.lastname: Donovan
authors.forename: B A
authors.initials: BA
authors.lastname: Baldo
mesh_terms: D000485:Allergens / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D000862:Ant Venoms / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D001000:Ants / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D001483:Base Sequence; D005075:Biological Evolution; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005796:Genes; D007073:Immunoglobulin E / Q000378:metabolism; D019476:Insect Proteins; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D000485:Allergens; D000862:Ant Venoms; D018076:DNA, Complementary; D019476:Insect Proteins; C079435:Myr p I; C096132:Myr p II protein, Myrmecia pilosula; D021382:Protein Sorting Signals; D007073:Immunoglobulin E