title: A novel elicitin necrotic site revealed by alpha-cinnamomin sequence and site-directed mutagenesis.
abstract: Elicitins are 10 kDa proteins secreted by Phytophthora fungi, that elicit resistance against certain plant pathogens. Various natural molecules, mutated recombinant elicitins and synthetic peptides were previously shown to differentially induce in tobacco leaf necrosis and defence genes, activities borne by several sites which were identified. We report a novel necrosis-determining residue at position 25, revealed by the comparison of the necrotic activity and sequence of alpha-cinnamomin with those of other known elicitins. Using a modified recombinant beta-cryptogein, expressed in Pichia pastoris, we show that the substitution of asparagine 25 by a serine leads to a significant enhancement of the necrotic activity.
authors.affiliation: INRA, Jouy-en-Josas, France.
authors.forename: V
authors.initials: V
authors.lastname: Perez
authors.forename: J C
authors.initials: JC
authors.lastname: Huet
authors.forename: M
authors.initials: M
authors.lastname: O'Donohue
authors.forename: C
authors.initials: C
authors.lastname: Nespoulous
authors.forename: J C
authors.initials: JC
authors.lastname: Pernollet
mesh_terms: D020418:Algal Proteins; D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009183:Mycotoxins / Q000737:chemistry / Q000235:genetics*; D010838:Phytophthora / Q000737:chemistry / Q000235:genetics* / Q000472:pathogenicity; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D018515:Plant Leaves; D010947:Plants, Toxic; D011506:Proteins / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D011994:Recombinant Proteins / Q000235:genetics; D054790:Ribosome Inactivating Proteins, Type 2; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana / Q000382:microbiology
chemical_list: D020418:Algal Proteins; D005656:Fungal Proteins; D009183:Mycotoxins; D011506:Proteins; D011994:Recombinant Proteins; D054790:Ribosome Inactivating Proteins, Type 2; C061930:cinnamomin, Phytophthora cinnamomi