title: Pichia anomala DBVPG 3003 secretes a ubiquitin-like protein that has antimicrobial activity.
abstract: The yeast strain Pichia anomala DBVPG 3003 secretes a killer toxin (Pikt) that has antifungal activity against Brettanomyces/Dekkera sp. yeasts. Pikt interacts with beta-1,6-glucan, consistent with binding to the cell wall of sensitive targets. In contrast to that of toxin K1, secreted by Saccharomyces cerevisiae, Pikt killer activity is not mediated by an increase in membrane permeability. Purification of the toxin yielded a homogeneous protein of about 8 kDa, which showed a marked similarity to ubiquitin in terms of molecular mass and N-terminal sequences. Pikt is also specifically recognized by anti-bovine ubiquitin antibodies and, similar to ubiquitin-like peptides, is not absorbed by DEAE-cellulose. However, Pikt differs from ubiquitin in its sensitivity to proteolytic enzymes. Therefore, Pikt appears to be a novel ubiquitin-like peptide that has killer activity.
authors.affiliation: Istituto di Biotecnologie Biochimiche, Università Politecnica delle Marche, Via Ranieri, 60131 Ancona, Italy.
authors.forename: Jessica
authors.initials: J
authors.lastname: De Ingeniis
authors.forename: Nadia
authors.initials: N
authors.lastname: Raffaelli
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ciani
authors.forename: Ilaria
authors.initials: I
authors.lastname: Mannazzu
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D055168:Brettanomyces / Q000187:drug effects; D055167:Dekkera / Q000187:drug effects; D005656:Fungal Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010843:Pichia / Q000378:metabolism*; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D014452:Ubiquitins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*
chemical_list: D000935:Antifungal Agents; D005656:Fungal Proteins; D014452:Ubiquitins