Chemical synthesis, expression and mutagenesis of a gene encoding beta-cryptogein, an elicitin produced by Phytophthora cryptogea

• Published in: Plant molecular biology 1995-02, Vol.27 (3), p.577-586
• Main Authors: O'Donohue, M.J, Gousseau, H, Huet, J.C, Tepfer, D, Pernollet, J.C
• Format: Article
• Language: English
• Subjects: Algal Proteins; Amino Acid Sequence; amino acid sequences; Base Sequence; bioassays; elicitors; Fungal Proteins - biosynthesis; Fungal Proteins - chemistry; Fungal Proteins - genetics; Fungal Proteins - isolation & purification; Fungal Proteins - pharmacology; genbank/x83001; Gene Expression; Genes, Plant - genetics; Genes, Synthetic - genetics; Molecular Sequence Data; Molecular Weight; Mutagenesis, Site-Directed; necrosis; Nicotiana - drug effects; Nicotiana tabacum; nucleotide sequences; Phytophthora - genetics; Phytophthora cryptogea; Plants, Toxic; proteins; Recombinant Fusion Proteins - biosynthesis; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - isolation & purification; Recombinant Fusion Proteins - pharmacology; Sequence Analysis, DNA; site-directed mutagenesis; synthesis; synthetic genes
• ISSN: 0167-4412; 1573-5028
• DOI: 10.1007/BF00019323

Elicitins are 10 kDa holoproteins secreted by Phytophthora fungi, that elicit an incompatible hypersensitive reaction, leading to resistance against fungal and bacterial plant pathogens. Comparison of primary sequences of alpha-elicitins and beta-elicitins indicated several potential necrotic activity-determining residues. All of the highly necrotic beta-elicitins have a hydrophilic residue (usually lysine) at position 13, whereas in the less necrotic alpha-elicitins this residue is replaced by a valine. Here, we report the synthesis and expression of a gene encoding a highly necrotic elicitin, beta-cryptogein, and we show that the substitution of Lys-13 of this recombinant protein by a valine leads to a drastic alteration to the necrotic activity of the recombinant protein.