title: Comparative structural and functional characterization of putative protein effectors belonging to the PcF toxin family from Phytophthora spp.
abstract: The PcF Toxin Family (Pfam 09461) includes the characterized phytotoxic protein PcF from Phytophthora cactorum, as well as several predicted protein effectors from other Phytophthora species recently identified by comparative genomics. Here we provide first evidence that such 'putatives', recombinantly expressed in bacteria and purified to homogeneity, similarly to PcF, can trigger defense-related responses on tomato, that is leaf withering and phenylalanine ammonia lyase induction, although with various degrees of effectiveness. In addition, structural prediction by computer-aided homology modeling and subsequent structural/functional comparison after rational engineering of the disulfide-structured protein fold by site-directed mutagenesis, highlighted the surface-exposed conserved amino acid stretch SK(E/C)C as a possible structural determinant responsible for the differential phytotoxicity within this family of cognate protein effectors.
authors.affiliation: Dipartimento Patologia Molecolare e Terapie Innovative, Sezione Biochimica, Università Politecnica delle Marche, Ancona, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Orsomando
authors.forename: Lucia
authors.initials: L
authors.lastname: Brunetti
authors.forename: Kathleen
authors.initials: K
authors.lastname: Pucci
authors.forename: Barbara
authors.initials: B
authors.lastname: Ruggeri
authors.forename: Silverio
authors.initials: S
authors.lastname: Ruggieri
mesh_terms: D000595:Amino Acid Sequence; D018551:Solanum lycopersicum / Q000469:parasitology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010838:Phytophthora / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D040681:Structural Homology, Protein; D014118:Toxins, Biological / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D011506:Proteins; D014118:Toxins, Biological