title: Fip-vvo, a new fungal immunomodulatory protein isolated from Volvariella volvacea.
abstract: A new fungal immunomodulatory protein (Fip) has been purified from the edible mushroom, Volvariella volvacea, and designated Fip-vvo. Analysis of the purified protein by SDS/PAGE followed by Coomassie Blue staining demonstrated that Fip-vvo is a single polypeptide with an apparent molecular mass of 15 kDa. Periodic acid/Schiff staining showed that this single polypeptide lacks carbohydrates. Using an in vitro bioassay measuring blast-formation stimulatory activity, Fip-vvo was shown to stimulate the maximum proliferation of human peripheral blood lymphocytes at a concentration of 5 microg/ml. Fip-vvo was capable of agglutinating rat red blood cells. Neither haemagglutination nor mitogenic activities were inhibited by mono- or dimeric sugars. In vivo, repeat administration of Fip-vvo greatly reduced the production of BSA-induced Arthus reaction in mice, whereas little effect was observed on the prevention of systemic anaphylaxis reactions. The selectively enhanced transcriptional expression of interleukin (IL)-2, IL-4, interferon-gamma, tumour necrosis factor-alpha, lymphotoxin and IL-2 receptor by Fip-vvo was also demonstrated by reverse transcriptase-PCR. This finding suggests that Fip-vvo exerts its immunomodulatory effects via cytokine regulation. In addition, the complete amino acid sequence of Fip-vvo was obtained by direct protein sequencing. This protein consists of 112 amino acid residues with a blocked N-terminal end and has a calculated molecular mass of 12667 Da not including the N-terminal blocking group. By gel filtration analysis, Fip-vvo exhibited a molecular mass of 26 kDa for the native molecules in PBS. This result indicates that native Fip-vvo is most likely a non-covalently associated homodimeric molecule.
authors.affiliation: Institute of Biochemistry, College of Medicine, National Taiwan University, Taipei, Taiwan 100, Republic of China.
authors.forename: H C
authors.initials: HC
authors.lastname: Hsu
authors.forename: C I
authors.initials: CI
authors.lastname: Hsu
authors.forename: R H
authors.initials: RH
authors.lastname: Lin
authors.forename: C L
authors.initials: CL
authors.lastname: Kao
authors.forename: J Y
authors.initials: JY
authors.lastname: Lin
mesh_terms: D000276:Adjuvants, Immunologic / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001487:Basidiomycota / Q000737:chemistry*; D002455:Cell Division / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000737:chemistry; D006801:Humans; D007166:Immunosuppressive Agents / Q000737:chemistry; D007249:Inflammation / Q000188:drug therapy; D037102:Lectins; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D016415:Sequence Alignment
chemical_list: D000276:Adjuvants, Immunologic; D005656:Fungal Proteins; D007166:Immunosuppressive Agents; D037102:Lectins; C061148:LZ-8 protein, Ganoderma lucidum