Polypeptides against plant pathogenic fungi
The present invention discloses polypeptides comprising an amino acid sequence being identical with at least 12 contiguous amino acid residues of SEQ ID No 2. The polypeptides according to the invention are effective against fungi, especially against fungi causing plant diseases, and against fungi colonizing agricultural products. The invention further discloses processes for preparing such polypeptides, and nucleic acids coding for such polypeptides. In addition, the invention relates to processes and preparations for treating plants using the polypeptides according to the invention, and to the use of the nucleic acids according to the invention for producing crops that are protected against damage from fungi.
1. A polypeptide comprising an amino acid sequence identical with SEQ ID NO: 1 or SEQ ID NO: 2, wherein (i) the N-terminal end is derivatized by partial alkylation, complete alkylation, or acylation, (ii) the C-terminal end is derivatized by amidation or esterification, (iii) the peptide chain is derivatized by PEGylation or HESylation, or (iv) a combination thereof.
2. The polypeptide according to claim 1 , which leads to a half-maximum inhibition of the spore germination of Fusarium graminearum at a concentration of 1 to 1000 μM.
3. The polypeptide according to claim 1 , which is effective against the growth of organisms of the genera Fusarium and/or Phytophthora.
4. The polypeptide according to claim 1 , having the following sequence
(SEQ ID NO: 2)
Z 1 -QHGYGAGGHGQQGYGSQHSSHAPQGGHVVREQGFSGHVHE
QQAGHHHEAGHHEQAGHHEQSGQQVHGQGHGYK-Z 2 ,
where
Z 1 is the N-terminal end of the polypeptide, the derivatized N-terminal amino group of the polypeptide, or a chain of up to ten arbitrary amino acids; and
Z 2 is the C-terminal end of the polypeptide, the derivatized C-terminal carboxy group of the polypeptide, or a chain of up to ten arbitrary amino acids;
wherein at least one of Z 1 or Z 2 is derivatized or a chain of up to ten arbitrary amino acids.
5. The polypeptide according to claim 4 , wherein Z 2 has an amino acid sequence of SHGY-Z 3 , wherein Z 3 the C-terminal end of the polypeptide, the derivatized C-terminal carboxy group of the polypeptide, or a chain of up to six arbitrary amino acids, and wherein Z 1 is derivatized or has a chain of up to ten arbitrary amino acids or Z 3 is derivatized or has a chain of up to six amino acids.
6. The polypeptide according to claim 1 , wherein the polypeptide has D-amino acids in part, D-amino acids completely, or a D-retro-inverso peptide structure.
7. A polynucleotide coding for the polypeptide according to claim 1 .
8. A method of using the polypeptide according to claim 1 the method comprising applying the polypeptide to a plant for controlling fungi or oomycetes.
9. A cell, except for wild type cells of Lucilia sericata , wherein said cell contains a nucleic acid for the expression of a polypeptide according to claim 1 .
10. A transgenic crop containing a cell according to claim 9 .
11. The polypeptide according to claim 1 , which leads to a half-maximum inhibition of the spore germination of Fusarium graminearum at a concentration of 2 μM.
12. The method according to claim 8 , wherein the fungi cause plant diseases.
13. The method according to claim 8 , wherein the fungi are selected from the group consisting of the genus Fusarium and the genera Phytophthora , and the oomycetes are from the class Peronosporomycetes.