title: Ostreopexin: a hemopexin fold protein from the oyster mushroom, Pleurotus ostreatus.
abstract: Proteins with hemopexin repeats are widespread in viruses, prokaryotes and eukaryotes. We report here for the first time the existence of a protein in fungi with the four-bladed β-propeller fold that is typical for hemopexin-like proteins. This protein was isolated from the edible basidiomycetous fungus Pleurotus ostreatus and is named ostreopexin. It binds to Ni(2+)-NTA-agarose, and is structurally and functionally very similar to PA2 albumins isolated from legume seeds and the hemopexin fold protein from rice. Like these plant proteins, ostreopexin shows reversible binding to hemin with moderate affinity, but does not bind to polyamines. We suggest that ostreopexin participates in intracellular management of metal (II or III)-chelates.
authors.affiliation: Department of Biology, University of Ljubljana, Ljubljana, Slovenia. katja.ota@bf.uni-lj.si
authors.forename: Katja
authors.initials: K
authors.lastname: Ota
authors.forename: Miha
authors.initials: M
authors.lastname: Mikelj
authors.forename: Tadeja
authors.initials: T
authors.lastname: Papler
authors.forename: Adrijana
authors.initials: A
authors.lastname: Leonardi
authors.forename: Igor
authors.initials: I
authors.lastname: Križaj
authors.forename: Peter
authors.initials: P
authors.lastname: Maček
mesh_terms: D000418:Albumins / Q000378:metabolism; D002853:Chromatography, Liquid; D007887:Fabaceae / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D006427:Hemin / Q000378:metabolism*; D006466:Hemopexin / Q000737:chemistry* / Q000378:metabolism; D009571:Nitrilotriacetic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D009942:Organometallic Compounds / Q000378:metabolism*; D012275:Oryza / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D020076:Pleurotus / Q000254:growth & development / Q000378:metabolism*; D011073:Polyamines / Q000378:metabolism*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000378:metabolism*; D012639:Seeds / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D000418:Albumins; D005656:Fungal Proteins; D009942:Organometallic Compounds; D010940:Plant Proteins; D011073:Polyamines; D011994:Recombinant Proteins; C088321:nickel nitrilotriacetic acid; D006427:Hemin; D006466:Hemopexin; D009571:Nitrilotriacetic Acid