title: Influence of zinc ions on protein secretion in a heavy metal tolerant strain of the ericoid mycorrhizal fungus Oidiodendron maius.
abstract: A heavy metal tolerant strain of the ericoid mycorrhizal species Oidiodendron maius, isolated from soil heavily contaminated with zinc, was previously shown to tolerate high concentrations of zinc and cadmium ions in the growth medium. We have investigated some of the specific molecular responses of this fungal strain to the presence of increasing concentrations of zinc ions in the growth medium. In particular, we show that zinc ions induce a general change in the array of secreted proteins, with a shift towards the production of more basic, low molecular weight polypeptides. Some of these proteins were microsequenced and identified through homology search in databases. Among them are hydrolytic enzymes (nuclease, proteinase, lysozyme) and two superoxide dismutase isoforms. The latter are antioxidant enzymes known to play a role in heavy metal response in plants, animals and microorganisms.
authors.affiliation: Dipartimento di Biologia Vegetale dell'Università di Torino, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Martino
authors.forename: Barbara
authors.initials: B
authors.lastname: Franco
authors.forename: Giovanni
authors.initials: G
authors.lastname: Piccoli
authors.forename: Vilberto
authors.initials: V
authors.lastname: Stocchi
authors.forename: Silvia
authors.initials: S
authors.lastname: Perotto
mesh_terms: D000595:Amino Acid Sequence; D002413:Cations, Divalent / Q000494:pharmacology; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism*; D005658:Fungi / Q000187:drug effects* / Q000201:enzymology; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D007526:Isoelectric Point; D008969:Molecular Sequence Data; D008970:Molecular Weight; D020539:Sequence Analysis, Protein; D015032:Zinc / Q000494:pharmacology*
chemical_list: D002413:Cations, Divalent; D005656:Fungal Proteins; D015032:Zinc