title: Identification and expression of Pen c 2, a novel allergen from Penicillium citrinum.
abstract: The mould genus, Penicillium, is known to be a significant source of environmental aero-allergens. One important allergen from Penicillium citrinum, Pen c 2, has been identified by means of two-dimensional immunoblotting using IgE-containing patients' sera. This novel allergen was cloned, sequenced and expressed in Escherichia coli. The cloned cDNA encodes a large 457-amino acid protein precursor containing a 16-amino acid signal peptide, a 120-amino acid propeptide and the 321-amino acid mature protein. Comparison of the Pen c 2 sequence with known protein sequences revealed shared high sequence similarities with two vacuolar serine proteases from Aspergillus niger and Saccharomyces cerevisiae. Asp-46, His-78 and Ser-244 were found to constitute the catalytic triad of the 39-kDa Pen c 2. The DNA coding for Pen c 2 was cloned into vector PQE-30 and expressed in E. coli as a His-tag fusion protein that bound serum IgE from Penicillium-allergic patients on immunoblots. Recombinant Pen c 2 could therefore be used effectively for diagnosis and also potentially for the treatment of mould-derived allergic disorders.
authors.affiliation: Institute of Biochemistry, College of Medicine, National Taiwan University, No. 1, Jen-Ai Road, Taipei, Taiwan 100. lupin@ha.mc.ntu. edu.tw
authors.forename: L P
authors.initials: LP
authors.lastname: Chow
authors.forename: N Y
authors.initials: NY
authors.lastname: Su
authors.forename: C J
authors.initials: CJ
authors.lastname: Yu
authors.forename: B L
authors.initials: BL
authors.lastname: Chiang
authors.forename: H D
authors.initials: HD
authors.lastname: Shen
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000595:Amino Acid Sequence; D000946:Antigens, Fungal / Q000276:immunology*; D001483:Base Sequence; D003001:Cloning, Molecular; D000939:Epitopes; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology; D007073:Immunoglobulin E / Q000276:immunology; D008969:Molecular Sequence Data; D010407:Penicillium / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics; D014617:Vacuoles / Q000201:enzymology
chemical_list: D000485:Allergens; D000946:Antigens, Fungal; D000939:Epitopes; D011994:Recombinant Proteins; C120860:pen c 2; D007073:Immunoglobulin E; D012697:Serine Endopeptidases